WILL universe ever end?
WILL universe ever end?
| gaurav.baral1 wrote: |
| WILL universe ever end? |
The measure of the universe is shown to be infinite, but well behaved, in this* model. ed.
* http://arxiv.org/PS_cache/hep-th/pdf/0609/0609095.pdf
Yes, the universe will eventually end. However, this is going to take billions and billions of years.
Scientifically
Eventually the effect of the expanding galaxies etc. created by the big bang will cease and all of the galaxies will be pulled back by gravity into the point from which the universe began. This in turn could create a new Big Bang and the cycle will contiune indefinately.
Religously
Wait for apocalypse. During this period all of life will end. Therefore for us at least the universe will end.
Scientifically
Eventually the effect of the expanding galaxies etc. created by the big bang will cease and all of the galaxies will be pulled back by gravity into the point from which the universe began. This in turn could create a new Big Bang and the cycle will contiune indefinately.
Religously
Wait for apocalypse. During this period all of life will end. Therefore for us at least the universe will end.
Unless you mean does the universe end (are there boundries to it) in which case I don't know. It is possible that the universe could have a 4th dimension so flying off one edge brings you back onto the other side. But we don't really know yet.
| llobo1 wrote: |
| Yes, the universe will eventually end. However, this is going to take billions and billions of years.
Scientifically Eventually the effect of the expanding galaxies etc. created by the big bang will cease and all of the galaxies will be pulled back by gravity into the point from which the universe began. This in turn could create a new Big Bang and the cycle will contiune indefinately. |
Actually, i believe that current evidence indicates that the universe will not collapse back in on itself (no "Big Crunch"). Instead it will go on expanding forever ("Heat Death", or something similar).
The universe is not only expanding, the expansion is accelerating. So its going to continue to expand forever until all stars die out.
well if expansion is acceleration, wouldn't it reach the point that it goes so fast that it begins to go back in time and retract
| llobo1 wrote: |
| Unless you mean does the universe end (are there boundries to it) in which case I don't know. It is possible that the universe could have a 4th dimension so flying off one edge brings you back onto the other side. But we don't really know yet. |
Yes i agree with llobo1, and i have read some articles that the universe could infact just be a giant space warp. For instance if you took off from earth and went "north", you would eventually go so far "north" that you would end up back at earth from the "south". I believe that this is what the universe does but I am not completely sure. I will be waitng for the scientists of our "new" age to find the answer to that question.
| ZealousZ wrote: |
| well if expansion is acceleration, wouldn't it reach the point that it goes so fast that it begins to go back in time and retract |
That would require the universe to expand faster than the speed of light but that would require and infinite amount of energy to exasperate to faster than the speed of light. So no, the universe's expansion could exhilarate to 99.999% the speed of light.
| ZealousZ wrote: |
| well if expansion is acceleration, |
expansion is not acceleration.
Also, even if the universe compacted back into one big chunk of mass and energy, as it supposedly was before the big bang, would that really be the end of the universe? It would still be there, just different.
| ocalhoun wrote: | ||
expansion is not acceleration. |
i think he meant "if the expansion is accelerating", which it apparently is.
| ocalhoun wrote: |
| Also, even if the universe compacted back into one big chunk of mass and energy, as it supposedly was before the big bang, would that really be the end of the universe? It would still be there, just different. |
That's really splitting hairs if nothing - no time, space, matter or energy - exists anymore. Whether the universe crunches or fizzles, there will nothing coherent left. To argue that the universe would still exist after either eventuality is equivalent to suggesting that a building that had a nuclear bomb explode on it and was vapourized still exists because the (sub)atomic matter that made it up was not destroyed.
So the universe is continuing to expand. But what is it expanding into?? If it is expanding there must be something for it to expand into? But the universe is supposed to include everything there is. So maybe it's not that the universe is expanding but that the galaxies are just flying into space which before was empty.
Of course everything has to end at some point. The universe willl probably end when the Sun blows up or dies. That will take some billion years but it will eventually happen.
| Nerdlings wrote: |
| Of course everything has to end at some point. The universe willl probably end when the Sun blows up or dies. That will take some billion years but it will eventually happen. |
The universe is a lot more than just our sun!
Where does the energy come from to accelerate the expansion of the universe?
| Indi wrote: |
| if nothing - no time, space, matter or energy - exists anymore |
How could that happen? Isn't it impossible to "lose" energy - you can only convert it to a different kind?
This is one of the most widely debated topics in science. On one extreme, you have creationists, who believe in the apocalypse, rapture, or other things of the sort. The other end (where I am located) believes mainly in one of two theories. There is the oscillating theory and the heat death theory (that's not the real name, but meh).
In the oscillating theory, the universe explodes (if you can say that). It expands until it reaches a critical point. At this critical point, the expansion in stopped by mass in the universe. It then begins to contract, until it reaches a nearly dimensionless clump of matter. It then "Bangs" outward and causes the cycle to start again.
The heat death theory is the same in the beginning, except the universe doesn't stop expanding. It continues expanding. Eventually, all matter in the universe is lead (too heavy to fuse). The temperature quickly drops to absolute zero. Black holes "dissolve", and there is no variation of energy in the universe. There may be energy, but it cannot be used for work.
That's a basic breakdown of all current theories. There is also the archaic steady-state theory, which matter is created at the center of the universe proportionate to the rate of expansion. This was disproved (strange things were found large distances away, stars redshifting & blueshifting away and towards us). As for what the universe is expanding into, no one really knows. One theory is that our universe is expanding into a multiverse. I can't explain it, so you might want to check wikipedia on that one. If you want information on the apocalypse or the rapture, go to church.
In the oscillating theory, the universe explodes (if you can say that). It expands until it reaches a critical point. At this critical point, the expansion in stopped by mass in the universe. It then begins to contract, until it reaches a nearly dimensionless clump of matter. It then "Bangs" outward and causes the cycle to start again.
The heat death theory is the same in the beginning, except the universe doesn't stop expanding. It continues expanding. Eventually, all matter in the universe is lead (too heavy to fuse). The temperature quickly drops to absolute zero. Black holes "dissolve", and there is no variation of energy in the universe. There may be energy, but it cannot be used for work.
That's a basic breakdown of all current theories. There is also the archaic steady-state theory, which matter is created at the center of the universe proportionate to the rate of expansion. This was disproved (strange things were found large distances away, stars redshifting & blueshifting away and towards us). As for what the universe is expanding into, no one really knows. One theory is that our universe is expanding into a multiverse. I can't explain it, so you might want to check wikipedia on that one. If you want information on the apocalypse or the rapture, go to church.
| Indi wrote: |
|
i think he meant "if the expansion is accelerating", which it apparently is. |
Oh, Well, that just shows the importance of proper grammar.
| Indi wrote: | ||
That's really splitting hairs if nothing - no time, space, matter or energy - exists anymore. Whether the universe crunches or fizzles, there will nothing coherent left. To argue that the universe would still exist after either eventuality is equivalent to suggesting that a building that had a nuclear bomb explode on it and was vapourized still exists because the (sub)atomic matter that made it up was not destroyed. |
So, an incoherent universe doesn't count as a universe?
I suppose this depends on how you define the word 'universe'.
| Google: Define: Universe wrote: |
|
*everything that exists anywhere; "they study the evolution of the universe"; "the biggest tree in existence" *The totality of space and time, along with all the matter and energy in it. (And others less pertinent) |
If you took the first definition there, it might be construed to support your position, in that everything that exists everywhere would be destroyed.
However, if you took the second definition, it would be difficult to explain how you could destroy both matter and energy without turning one into the other, much less how you could do that to all the matter and energy in the entire universe.
| ocalhoun wrote: | ||
Oh, Well, that just shows the importance of proper grammar. |
True.
| ocalhoun wrote: | ||||||
So, an incoherent universe doesn't count as a universe? I suppose this depends on how you define the word 'universe'.
If you took the first definition there, it might be construed to support your position, in that everything that exists everywhere would be destroyed. However, if you took the second definition, it would be difficult to explain how you could destroy both matter and energy without turning one into the other, much less how you could do that to all the matter and energy in the entire universe. |
Not a problem, really.
As a matter of fact, if the universe dies a heat death (only one of the possible ends, but the one most likely with our current scientific knowledge), there will be no matter left. It will all have been converted to energy. However! Don't assume that all energy is equal. It is true that energy can only be converted from one form to another... but that doesn't mean that energy can always be converted from one form to another. There are forms of energy that, once converted to, cannot be converted back from. The concept is referred to as "usable energy", and is related to entropy. When the universe dies, the energy will still be "there", but it will no longer be in a form that can be used. It will be "dead" energy, energy in an incoherent form, at maximum entropy. There will be no way that anything can happen, because the energy to "fuel" events will be gone. There will be - in the truest sense of the word - nothing. No form, no thought, no action, no motion, no matter, no time, no nothing. Yes, the energy will still "be there", but absolutely useless. If you want to call that a universe, go nuts, but then i would ask whether or not you would call a glowing radioactive puddle that used to be a person but has just been melted by a death ray a human being. i mean, after all, all the stuff that made up the person is still right there in that puddle. Seems a little silly to me, though, because it certainly doesn't have any of the characteristics or capabilities that a person does. Likewise for the dead energy at the end of the universe - it won't have any of the capabilities or characteristics of what i would consider a universe, it just happens to be made of the same stuff. The universe would be, forever, gone. Just the stuff it was made of would remain.
The same is true if the universe collapses in a "Big Crunch". Yeah, sure, all the energy is still there, but not in any useful form. It's just a big (or little) ball of dimensionless, featureless potential. When it explodes (if it explodes again), it will form a universe... but not the universe that existed before. That universe is, forever, gone. Just the stuff it was made of remains.
So if you define universe as just the stuff the universe is made up of, then yes, the universe may exist "forever" (although, since time will die, "forever" doesn't mean much). But i think the universe is more than the sum of the stuff that makes it up - i think the patterns and forms in the universe are as much a part of what defines a universe as the building materials. i wouldn't say a pane of glass and a pile of sand are the same thing just because they are made up of the same components, would you? Form and structure are important, and it is that which will be lost forever when the universe dies, even if the raw materials remain (albeit in a form that is unusable and can never again create any form or structure).
It probably will. everything that starts has an end, and if the big bang happened once, it could have happened hundreds of other times.
I think a better question is: WILL time ever end? because to us that's the main thing.
If time keeps going, then the universe, as we know it, is continuing. As Indi said, When (if) the Universe collapses in the big crunch, all the energy is still there, but the universe isn't really.
Yeah, and I agree with that. I'd say the Universe basically "started" when the Big Bang occurred. so it would "end" when the Big Crunch happens.
I guess that's one of life's unanswered questions. like how a photon can be a particle and a wave at the same time.
Man, those physists need to hurry up and answer them asap.
All the energy wouldn't disappear, I think, It would all be in the Black hole.
Well, I wouldn't call it an extreme...I for one, am on the creationist side, except that I know that God created the world through science. How the end will come out I don't know.
One interesting Idea that hasn't been mentioned yet, and I find fascinating, is this:
What if the Universe is circular? When the Universe keeps expanding, it eventually expands back into itself, and we have the big crunch, except without the universe actually changing direction.
It's also possible that It's just something I read somewhere and actually doesn't work. Our minds can't really comprehend it though....weird. huh?
If time keeps going, then the universe, as we know it, is continuing. As Indi said, When (if) the Universe collapses in the big crunch, all the energy is still there, but the universe isn't really.
| Indi wrote: |
|
That's really splitting hairs if nothing - no time, space, matter or energy - exists anymore. Whether the universe crunches or fizzles, there will nothing coherent left. To argue that the universe would still exist after either eventuality is equivalent to suggesting that a building that had a nuclear bomb explode on it and was vapourized still exists because the (sub)atomic matter that made it up was not destroyed. |
Yeah, and I agree with that. I'd say the Universe basically "started" when the Big Bang occurred. so it would "end" when the Big Crunch happens.
| Cibes wrote: |
| Where does the energy come from to accelerate the expansion of the universe? |
I guess that's one of life's unanswered questions. like how a photon can be a particle and a wave at the same time.
Man, those physists need to hurry up and answer them asap.
| Cibes wrote: |
| How could that happen? Isn't it impossible to "lose" energy - you can only convert it to a different kind? |
All the energy wouldn't disappear, I think, It would all be in the Black hole.
| Badabinski wrote: |
| On one extreme, you have creationists, who believe in the apocalypse, rapture, or other things of the sort. The other end (where I am located) believes mainly in one of two theories. There is the oscillating theory and the heat death theory (that's not the real name, but meh). |
Well, I wouldn't call it an extreme...I for one, am on the creationist side, except that I know that God created the world through science. How the end will come out I don't know.
One interesting Idea that hasn't been mentioned yet, and I find fascinating, is this:
What if the Universe is circular? When the Universe keeps expanding, it eventually expands back into itself, and we have the big crunch, except without the universe actually changing direction.
It's also possible that It's just something I read somewhere and actually doesn't work. Our minds can't really comprehend it though....weird. huh?
On one part, the universe is expanding. Also, energy tends to dispatch itself in order to be in the same amount everywhere.
Consider the nuclear reactions going on a bit everywhere in the universe. Big atoms split into smaller atoms, which will then split themselves. Then, the smallest atoms (hydrogen) fuses to create slighty bigger atoms. What if it all ended with a few atoms types?
But that was an old and weird theory, utmostly utopic. I'd tend to believe more in the Heat Death, as some pointed out here.
Consider the nuclear reactions going on a bit everywhere in the universe. Big atoms split into smaller atoms, which will then split themselves. Then, the smallest atoms (hydrogen) fuses to create slighty bigger atoms. What if it all ended with a few atoms types?
But that was an old and weird theory, utmostly utopic. I'd tend to believe more in the Heat Death, as some pointed out here.
| Indi wrote: |
| i wouldn't say a pane of glass and a pile of sand are the same thing just because they are made up of the same components, would you? Form and structure are important, and it is that which will be lost forever when the universe dies, even if the raw materials remain (albeit in a form that is unusable and can never again create any form or structure). |
No, but I would say that a particular atom in that sand would still be the same thing even after the sand it was a part of has been made into glass. That single atom is as much a part of the universe as the entire pane of glass is.
Important, yes, but not all. Take your example of cold death; everything would still be there, but with no activity whatsoever, due to the absence of usable energy, therefore making it 'absolutely useless' because it has 'run out of fuel' (to use your own words). Now consider your car has run out of fuel (and for some reason you can't possible acquire more fuel). That does mean the car is useless (at least as for use as a mode of transportation), but it doesn't mean that the car has been destroyed.
| ocalhoun wrote: | ||
No, but I would say that a particular atom in that sand would still be the same thing even after the sand it was a part of has been made into glass. That single atom is as much a part of the universe as the entire pane of glass is. |
But when the universe ends that atom would be gone. The constituent components - electrons, protons and neutrons - would be gone. The subatomic quarks - gone. Everything gone. There would be nothing left to identify as a component of the glass. There would be nothing left to do any identifying either. You can never recover any part of what was once that pane of glass. It's all gone.
There's nothing left. Even the energy itself that it has collapsed into is functionally non-existent, because it can never be measured, used or observed.
| ocalhoun wrote: |
| Important, yes, but not all. Take your example of cold death; everything would still be there, but with no activity whatsoever, due to the absence of usable energy, therefore making it 'absolutely useless' because it has 'run out of fuel' (to use your own words). Now consider your car has run out of fuel (and for some reason you can't possible acquire more fuel). That does mean the car is useless (at least as for use as a mode of transportation), but it doesn't mean that the car has been destroyed. |
In this case, a more appropriate analogy would be that your car ran out of gas then melted to a puddle of slag. It's not just that the universe has no more usable energy - time and matter have ceased to exist. Even if you were to provide an infusion of usable energy from somewhere (ie, refilling the car with gas), there's nothing left to run. It's gone, dead, finito. Pour gas on it all you want, it ain't goin' nowhere.
So yes, i would say that the car is destroyed.
| Indi wrote: |
| It's not just that the universe has no more usable energy - time and matter have ceased to exist. Even if you were to provide an infusion of usable energy from somewhere (ie, refilling the car with gas), there's nothing left to run. It's gone, dead, finito. Pour gas on it all you want, it ain't goin' nowhere.
So yes, i would say that the car is destroyed. |
So, ignoring the fact that it wouldn't technically be possible, adding energy to the universe would not revitalize it after the cause of it's end was lack of usable energy? Doesn't seem to make sense to me. What then would happen to the added energy? Also, why do you think time would stop? Just because it could not be measured?
As a side note, 'functionally non-existent' would not qualify as non-existent.
If the universe only exists if it stays in the same form it is in now, how can it exist at all except for a brief moment? All the parts of it, from the largest to the most tiny are constantly rearranging themselves, so what would be the difference if all of those parts rearranged themselves into one mass, then exploded again? It would still be just yet another rearrangement.
eventually the universe will be quadrillion time larger then it is now and be completely empty. then it will fall in on itself. That is my theory.
| ocalhoun wrote: |
| So, ignoring the fact that it wouldn't technically be possible, adding energy to the universe would not revitalize it after the cause of it's end was lack of usable energy? Doesn't seem to make sense to me. What then would happen to the added energy? Also, why do you think time would stop? Just because it could not be measured? |
It's not that it wouldn't be possible to add usable energy to the universe after it was dead - you'd just have to assume that that usable energy came from somewhere "outside" the universe. Of course, then the question becomes can there be anything "outside" the universe? While that's an important question in reality, it doesn't matter to a thought experiment. You want to hypothesize adding energy to a dead universe from somewhere else, go for it.
The universe is not a rechargable battery. Once it's energy is "used up" - that is, converted to it's lowest form - it can never be recovered. Ever. By anything. It's gone, used up, dead. If God could recover that energy, then he can also make a square circle. That's because that energy is dead. Gone. Useless. There is no way - no way - to get it back.
If you put more energy into the universe, you will not "turn it back on". You will have - to continue your analogy of the car - poured gasoline on the slagheap that used to be a car. It's not going to run again. Oh, sure, you can ignite the gas you just added and watch it burn, but it won't save the car. You could add even more energy and use some of the remains of the car to make a new car, then gas that up... but the original car is still gone. A universe would exist, but the universe would still be gone.
So if you added energy, you could create a new universe... but you could never recover the "material" of the old universe. It really is gone.
| ocalhoun wrote: |
| As a side note, 'functionally non-existent' would not qualify as non-existent. |
From a philosophical standpoint, perhaps. Consider, is your great-great grandfather gone? Technically, no. The material and energy that made him up must still exist in the universe. If i asked you, right now, about the current moment (not the past), "does your great-great-grandfather exist?" what will you answer?
The answer i would give is no. Some components and aspects that were once him continue to exist, but he himself is gone. He does not exist anymore.
Now, arguably, you could - in far out theory - collect all of the material and "energy" that made him up and recreate him. It wouldn't just be a copy of your grandfather, it would be him, exactly, made up of the same matter and energy that he was. So you could make him exist again. But during that period where he was gone, did he exist?
But with the universe, you cannot ever recover the dead energy that once made up the universe. So you can never even recover the universe. You can make a copy, but never the same universe over again. It's really, totally gone - even with far out theorizing, there is no way to recover it.
| ocalhoun wrote: |
| If the universe only exists if it stays in the same form it is in now, how can it exist at all except for a brief moment? All the parts of it, from the largest to the most tiny are constantly rearranging themselves, so what would be the difference if all of those parts rearranged themselves into one mass, then exploded again? It would still be just yet another rearrangement. |
Now you're just making a straw man argument. Nothing i have said or implied suggests that the universe has to stay in the same form. You made that up yourself in order to attack it. But it's obviously silly.
But you've also showed the flaw in your objection with your own words: "All the parts of it, from the largest to the most tiny are constantly rearranging themselves, so what would be the difference if all of those parts rearranged themselves into one mass, then exploded again?"
There are no more parts of it. They are all gone and cannot be recovered by any means. There is no more rearrangement, no more motion. It is cold and dead. Everything has stopped. There is nothing left to observe, and nothing left to observe it. The dead energy cannot be measured, and it cannot be recovered.
If you're silly argument were true, then a person would only exist for a brief moment, because people change all the time. Obviously that's not true. But when that person dies, even though they leave behind rotting biological matter (less 21 grams or whatever)... they're gone. That person no longer exists, even though their corpse may be rotting in your arms.
| newolder wrote: | ||
The measure of the universe is shown to be infinite, but well behaved, in this* model. ed. * http://arxiv.org/PS_cache/hep-th/pdf/0609/0609095.pdf |
Mind you, Sir Roger Penrose provides evidence (& predictions) of a different, 10-D reality at this web-cast from 6th February this year*.
Charged, massless entities, anyone? And, hasn't electron decay been discussed earlier too? Iirc, 10^23 years (edit) was mentioned as a half-life...
I'll have a rootle...
Yep, http://arxiv.org/abs/hep-th/0312325 but, as ever, the Prof. is correct in that he notes such work requires non-conservation of charge...
Also, what violation (CP or T) is made here, i wonder? http://www.answers.com/topic/muon-electron-decay-png
ed.
"Requires RealPlayer", t'internet says.
* http://real.bnl.gov/ramgen/bnl/penrose.rm
Last edited by newolder on Sun Feb 25, 2007 4:38 am; edited 1 time in total
Big Bang
I have read many scientific theories about how the universe was created, all being very long winded theories, as if proof to the author’s high academic standings. Prof. Friedmann, William Lane Craig, John Leslie, Hawking, Penrose, Guth, Linde's, Albrecht, Steinhardt's, Tryon's and Gott have all added life to the Big Bang Cosmology question. ‘Einstein equation' that lies at the heart of the General Theory of Relativity gave power to the original Friedmann’s theory and Prof. Hawkins was dabbling with quantum maths to prove his point.
I am not an expert within this field however I do have my own ideas based on what I believe to be logical facts.
The first being you cannot manufacture something if you do not have the basic materials;
1. The universe exists
2. Something must have caused the creation
Perhaps there is no such thing as total emptiness and emptiness cannot exist. That the very emptiness of space created the big bang as emptiness has to contain something. Maybe that the mechanisms Quantum physics are not fully understood perhaps instead of two quarks there are four; two matter quarks and two anti-matters that if all four met the set quarks then cease to exist. Would it of been possible that the big bang was caused the eruption of separating pairs of quarks spiralling outwards forming two new universes one of matter and the other of antimatter.
Perhaps both universes eventually meet and join together to create a void prior to a new rebirth. Could it be that antimatter is very dense, could it be black holes are made up of antimatter a product of the big bang; perhaps there is only one universe? Lets leave that problem to the theorist most properly someone as bright as the late Prof. Hawkins will provide an answer.
Research Notes.
Big Bang Theory, currently accepted explanation of the beginning of the universe. The big bang theory proposes that the universe was once extremely compact, dense, and hot. Some original event, a cosmic explosion called the big bang, occurred about 13.7 billion years ago, and the universe has since been expanding and cooling.
The theory is based on the mathematical equations, known as the field equations, of the general theory of relativity set forth in 1915 by Albert Einstein. In 1922 Russian physicist Alexander Friedmann provided a set of solutions to the field equations. These solutions have served as the framework for much of the current theoretical work on the big bang theory. American astronomer Edwin Hubble provided some of the greatest supporting evidence for the theory with his 1929 discovery that the light of distant galaxies was universally shifted toward the red end of the spectrum (see Redshift). Once “tired light” theories—that light slowly loses energy naturally, becoming more red over time—were dismissed, this shift proved that the galaxies were moving away from each other. Hubble found that galaxies farther away were moving away proportionally faster, showing that the universe is expanding uniformly. However, the universe’s initial state was still unknown
In the 1940s Russian-American physicist George Gamow worked out a theory that fit with Friedmann’s solutions in which the universe expanded from a hot, dense state. In 1950 British astronomer Fred Hoyle, in support of his own opposing steady-state theory, referred to Gamow’s theory as a mere “big bang,” but the name stuck. Indeed, a contest in the 1990s by Sky & Telescope magazine to find a better (perhaps more dignified) name did not produce one.
The overall framework of the big bang theory came out of solutions to Einstein’s general relativity field equations and remains unchanged, but various details of the theory are still being modified today. Einstein himself initially believed that the universe was static. When his equations seemed to imply that the universe was expanding or contracting, Einstein added a constant term to cancel out the expansion or contraction of the universe. When the expansion of the universe was later discovered, Einstein stated that introducing this “cosmological constant” had been a mistake.
After Einstein’s work of 1917, several scientists, including the abbé Georges Lemaître in Belgium, Willem de Sitter in Holland, and Alexander Friedmann in Russia, succeeded in finding solutions to Einstein’s field equations. The universes described by the different solutions varied. De Sitter’s model had no matter in it. This model is actually not a bad approximation since the average density of the universe is extremely low. Lemaître’s universe expanded from a “primeval atom.” Friedmann’s universe also expanded from a very dense clump of matter, but did not involve the cosmological constant. These models explained how the universe behaved shortly after its creation, but there was still no satisfactory explanation for the beginning of the universe.
In the 1940s George Gamow was joined by his students Ralph Alpher and Robert Herman in working out details of Friedmann’s solutions to Einstein’s theory. They expanded on Gamow’s idea that the universe expanded from a primordial state of matter called ylem consisting of protons, neutrons, and electrons in a sea of radiation. They theorized the universe was very hot at the time of the big bang (the point at which the universe explosively expanded from its primordial state), since elements heavier than hydrogen can be formed only at a high temperature. Alpher and Hermann predicted that radiation from the big bang should still exist. Cosmic background radiation roughly corresponding to the temperature predicted by Gamow’s team was detected in the 1960s, further supporting the big bang theory, though the work of Alpher, Herman, and Gamow had been forgotten.
The big bang theory seeks to explain what happened at or soon after the beginning of the universe. Scientists can now model the universe back to 10-43 seconds after the big bang. For the time before that moment, the classical theory of gravity is no longer adequate. Scientists are searching for a theory that merges gravity (as explained by Einstein's general theory of relativity) and quantum mechanics but have not found one yet. Many scientists have hope that string theory, also known as M-theory, will tie together gravity and quantum mechanics and help scientists explore further back in time (see Physics: Unified Field Theory).
Because scientists cannot look back in time beyond that early epoch, the actual big bang is hidden from them. There is no way at present to detect the origin of the universe. Further, the big bang theory does not explain what existed before the big bang. It may be that time itself began at the big bang, so that it makes no sense to discuss what happened “before” the big bang.
According to the big bang theory, the universe expanded rapidly in its first microseconds. A single force existed at the beginning of the universe, and as the universe expanded and cooled, this force separated into those we know today: gravity, electromagnetism, the strong nuclear force, and the weak nuclear force. A theory called the electroweak theory now provides a unified explanation of electromagnetism and the weak nuclear force theory (see Unified Field Theory). Physicists are now searching for a grand unification theory to also incorporate the strong nuclear force. String theory seeks to incorporate the force of gravity with the other three forces, providing a theory of everything (TOE).
One widely accepted version of big bang theory includes the idea of inflation. In this model, the universe expanded much more rapidly at first, to about 1050 times its original size in the first 10-32 second, then slowed its expansion. The theory was advanced in the 1980s by American cosmologist Alan Guth and elaborated upon by American astronomer Paul Steinhardt, Russian American scientist Andrei Linde, and British astronomer Andreas Albrecht. The inflationary universe theory (see Inflationary Theory) solves a number of problems of cosmology. For example, it shows that the universe now appears close to the type of flat space described by the laws of Euclid’s geometry: We see only a tiny region of the original universe, similar to the way we do not notice the curvature of the earth because we see only a small part of it. The inflationary universe also shows why the universe appears so homogeneous. If the universe we observe was inflated from some small, original region, it is not surprising that it appears uniform.
Once the expansion of the initial inflationary era ended, the universe continued to expand more slowly. The inflationary model predicts that the universe is on the boundary between being open and closed. If the universe is open, it will keep expanding forever. If the universe is closed, the expansion of the universe will eventually stop and the universe will begin contracting until it collapses. Whether the universe is open or closed depends on the density, or concentration of mass, in the universe. If the universe is dense enough, it is closed.
The universe cooled as it expanded. After about one second, protons formed. In the following few minutes—often referred to as the “first three minutes”—combinations of protons and neutrons formed the isotope of hydrogen known as deuterium as well as some of the other light elements, principally helium, as well as some lithium, beryllium, and boron. The study of the distribution of deuterium, helium, and the other light elements is now a major field of research. The uniformity of the helium abundance around the universe supports the big bang theory and the abundance of deuterium can be used to estimate the density of matter in the universe.
From about 380,000 to about 1 million years after the big bang, the universe cooled to about 3000°C (about 5000°F) and protons and electrons combined to make hydrogen atoms. Hydrogen atoms can only absorb and emit specific colors, or wavelengths, of light. The formation of atoms allowed many other wavelengths of light, wavelengths that had been interfering with the free electrons, to travel much farther than before. This change set free radiation that we can detect today. After billions of years of cooling, this cosmic background radiation is at about 3 K (-270°C/-454°F).The cosmic background radiation was first detected and identified in 1965 by American astrophysicists Arno Penzias and Robert Wilson.
The Cosmic Background Explorer (COBE) spacecraft, a project of the National Aeronautics and Space Administration (NASA), mapped the cosmic background radiation between 1989 and 1993. It verified that the distribution of intensity of the background radiation precisely matched that of matter that emits radiation because of its temperature, as predicted for the big bang theory. It also showed that cosmic background radiation is not uniform, that it varies slightly. These variations are thought to be the seeds from which galaxies and other structures in the universe grew.
Evidence indicates that the matter that scientists detect in the universe is only a small fraction of all the matter that exists. For example, observations of the speeds at which individual galaxies move within clusters of galaxies show that a great deal of unseen matter must exist to exert sufficient gravitational force to keep the clusters from flying apart. Cosmologists now think that much of the universe is dark matter—matter that has gravity but does not give off radiation that we can see or otherwise detect. One kind of dark matter theorized by scientists is cold dark matter, with slowly moving (cold) massive particles. No such particles have yet been detected, though astronomers have made up fanciful names for them, such as Weakly Interacting Massive Particles (WIMPs). Other cold dark matter could be nonradiating stars or planets, which are known as MACHOs (Massive Compact Halo Objects).
An alternative theory that explains the dark-matter model involves hot dark matter, where hot implies that the particles are moving very fast. Neutrinos, fundamental particles that travel at nearly the speed of light, are the prime example of hot dark matter. However, scientists think that the mass of a neutrino is so low that neutrinos can only account for a small portion of dark matter. If the inflationary version of big bang theory is correct, then the amount of dark matter and of whatever else might exist is just enough to bring the universe to the boundary between open and closed.
Scientists develop theoretical models to show how the universe’s structures, such as clusters of galaxies, have formed. Their models invoke hot dark matter, cold dark matter, or a mixture of the two. This unseen matter would have provided the gravitational force needed to bring large structures such as clusters of galaxies together. The theories that include dark matter match the observations, although there is no consensus on the type or types of dark matter that must be included. Supercomputers are important for making such models.
Astronomers continue to make new observations that are also interpreted within the framework of the big bang theory. No major problems with the big bang theory have been found, but scientists constantly adjust the theory to match the observed universe. In particular, a “standard model” of the big bang has been established by results from NASA's Wilkinson Microwave Anisotropy Probe (WMAP), launched in 2001 (see Cosmology). The probe studied the anisotropies, or ripples, in the temperature of cosmic background radiation at a higher resolution than COBE was capable of. These ripples indicate that regions of the young universe were very slightly hotter or cooler, by a factor of about 1/1000, than adjacent regions. WMAP’s observations suggest that the rate of expansion of the universe, called Hubble’s constant, is about 71 km/s/Mpc (kilometers per second per million parsecs, where a parsec is about 3.26 light-years). In other words, the distance between any two objects in space that are separated by a million parsecs increases by about 71 km every second in addition to any other motion they may have relative to one another. In combination with previously existing observations, this rate of expansion tells cosmologists that the universe is “flat,” though flatness here does not refer to the actual shape of the universe but rather that the geometric laws that apply to the universe match those of a flat plane.
To be flat, the universe must contain a certain amount of matter and energy, known as the critical density. The distribution of sizes of ripples detected by WMAP show that ordinary matter—like that making up objects and living things on Earth—accounts for only 4.4 percent of the critical density. Dark matter makes up an additional 23 percent. Astoundingly, the remaining 73 percent of the universe is composed of something else—a substance so mysterious that nobody knows much about it. Called “dark energy,” this substance provides the antigravity-like negative pressure that causes the universe's expansion to accelerate rather than slow down. This “accelerating universe” was detected independently by two competing groups of astronomers in the last years of the 20th century. The ideas of an accelerating universe and the existence of dark energy have caused astronomers to substantially modify previous ideas of the big bang universe.
WMAP's results also show that cosmic background radiation was set free about 380,000 years after the big bang, later than was previously thought, and that the first stars formed only 200,000 years after the big bang, earlier than anticipated. Further refinements to the big bang theory are expected from WMAP, which continues to collect data. An even more precise mission to study the beginnings of the universe, the European Space Agency’s Planck spacecraft, is scheduled to be launched in 2007.
I have read many scientific theories about how the universe was created, all being very long winded theories, as if proof to the author’s high academic standings. Prof. Friedmann, William Lane Craig, John Leslie, Hawking, Penrose, Guth, Linde's, Albrecht, Steinhardt's, Tryon's and Gott have all added life to the Big Bang Cosmology question. ‘Einstein equation' that lies at the heart of the General Theory of Relativity gave power to the original Friedmann’s theory and Prof. Hawkins was dabbling with quantum maths to prove his point.
I am not an expert within this field however I do have my own ideas based on what I believe to be logical facts.
The first being you cannot manufacture something if you do not have the basic materials;
1. The universe exists
2. Something must have caused the creation
Perhaps there is no such thing as total emptiness and emptiness cannot exist. That the very emptiness of space created the big bang as emptiness has to contain something. Maybe that the mechanisms Quantum physics are not fully understood perhaps instead of two quarks there are four; two matter quarks and two anti-matters that if all four met the set quarks then cease to exist. Would it of been possible that the big bang was caused the eruption of separating pairs of quarks spiralling outwards forming two new universes one of matter and the other of antimatter.
Perhaps both universes eventually meet and join together to create a void prior to a new rebirth. Could it be that antimatter is very dense, could it be black holes are made up of antimatter a product of the big bang; perhaps there is only one universe? Lets leave that problem to the theorist most properly someone as bright as the late Prof. Hawkins will provide an answer.
Research Notes.
Big Bang Theory, currently accepted explanation of the beginning of the universe. The big bang theory proposes that the universe was once extremely compact, dense, and hot. Some original event, a cosmic explosion called the big bang, occurred about 13.7 billion years ago, and the universe has since been expanding and cooling.
The theory is based on the mathematical equations, known as the field equations, of the general theory of relativity set forth in 1915 by Albert Einstein. In 1922 Russian physicist Alexander Friedmann provided a set of solutions to the field equations. These solutions have served as the framework for much of the current theoretical work on the big bang theory. American astronomer Edwin Hubble provided some of the greatest supporting evidence for the theory with his 1929 discovery that the light of distant galaxies was universally shifted toward the red end of the spectrum (see Redshift). Once “tired light” theories—that light slowly loses energy naturally, becoming more red over time—were dismissed, this shift proved that the galaxies were moving away from each other. Hubble found that galaxies farther away were moving away proportionally faster, showing that the universe is expanding uniformly. However, the universe’s initial state was still unknown
In the 1940s Russian-American physicist George Gamow worked out a theory that fit with Friedmann’s solutions in which the universe expanded from a hot, dense state. In 1950 British astronomer Fred Hoyle, in support of his own opposing steady-state theory, referred to Gamow’s theory as a mere “big bang,” but the name stuck. Indeed, a contest in the 1990s by Sky & Telescope magazine to find a better (perhaps more dignified) name did not produce one.
The overall framework of the big bang theory came out of solutions to Einstein’s general relativity field equations and remains unchanged, but various details of the theory are still being modified today. Einstein himself initially believed that the universe was static. When his equations seemed to imply that the universe was expanding or contracting, Einstein added a constant term to cancel out the expansion or contraction of the universe. When the expansion of the universe was later discovered, Einstein stated that introducing this “cosmological constant” had been a mistake.
After Einstein’s work of 1917, several scientists, including the abbé Georges Lemaître in Belgium, Willem de Sitter in Holland, and Alexander Friedmann in Russia, succeeded in finding solutions to Einstein’s field equations. The universes described by the different solutions varied. De Sitter’s model had no matter in it. This model is actually not a bad approximation since the average density of the universe is extremely low. Lemaître’s universe expanded from a “primeval atom.” Friedmann’s universe also expanded from a very dense clump of matter, but did not involve the cosmological constant. These models explained how the universe behaved shortly after its creation, but there was still no satisfactory explanation for the beginning of the universe.
In the 1940s George Gamow was joined by his students Ralph Alpher and Robert Herman in working out details of Friedmann’s solutions to Einstein’s theory. They expanded on Gamow’s idea that the universe expanded from a primordial state of matter called ylem consisting of protons, neutrons, and electrons in a sea of radiation. They theorized the universe was very hot at the time of the big bang (the point at which the universe explosively expanded from its primordial state), since elements heavier than hydrogen can be formed only at a high temperature. Alpher and Hermann predicted that radiation from the big bang should still exist. Cosmic background radiation roughly corresponding to the temperature predicted by Gamow’s team was detected in the 1960s, further supporting the big bang theory, though the work of Alpher, Herman, and Gamow had been forgotten.
The big bang theory seeks to explain what happened at or soon after the beginning of the universe. Scientists can now model the universe back to 10-43 seconds after the big bang. For the time before that moment, the classical theory of gravity is no longer adequate. Scientists are searching for a theory that merges gravity (as explained by Einstein's general theory of relativity) and quantum mechanics but have not found one yet. Many scientists have hope that string theory, also known as M-theory, will tie together gravity and quantum mechanics and help scientists explore further back in time (see Physics: Unified Field Theory).
Because scientists cannot look back in time beyond that early epoch, the actual big bang is hidden from them. There is no way at present to detect the origin of the universe. Further, the big bang theory does not explain what existed before the big bang. It may be that time itself began at the big bang, so that it makes no sense to discuss what happened “before” the big bang.
According to the big bang theory, the universe expanded rapidly in its first microseconds. A single force existed at the beginning of the universe, and as the universe expanded and cooled, this force separated into those we know today: gravity, electromagnetism, the strong nuclear force, and the weak nuclear force. A theory called the electroweak theory now provides a unified explanation of electromagnetism and the weak nuclear force theory (see Unified Field Theory). Physicists are now searching for a grand unification theory to also incorporate the strong nuclear force. String theory seeks to incorporate the force of gravity with the other three forces, providing a theory of everything (TOE).
One widely accepted version of big bang theory includes the idea of inflation. In this model, the universe expanded much more rapidly at first, to about 1050 times its original size in the first 10-32 second, then slowed its expansion. The theory was advanced in the 1980s by American cosmologist Alan Guth and elaborated upon by American astronomer Paul Steinhardt, Russian American scientist Andrei Linde, and British astronomer Andreas Albrecht. The inflationary universe theory (see Inflationary Theory) solves a number of problems of cosmology. For example, it shows that the universe now appears close to the type of flat space described by the laws of Euclid’s geometry: We see only a tiny region of the original universe, similar to the way we do not notice the curvature of the earth because we see only a small part of it. The inflationary universe also shows why the universe appears so homogeneous. If the universe we observe was inflated from some small, original region, it is not surprising that it appears uniform.
Once the expansion of the initial inflationary era ended, the universe continued to expand more slowly. The inflationary model predicts that the universe is on the boundary between being open and closed. If the universe is open, it will keep expanding forever. If the universe is closed, the expansion of the universe will eventually stop and the universe will begin contracting until it collapses. Whether the universe is open or closed depends on the density, or concentration of mass, in the universe. If the universe is dense enough, it is closed.
The universe cooled as it expanded. After about one second, protons formed. In the following few minutes—often referred to as the “first three minutes”—combinations of protons and neutrons formed the isotope of hydrogen known as deuterium as well as some of the other light elements, principally helium, as well as some lithium, beryllium, and boron. The study of the distribution of deuterium, helium, and the other light elements is now a major field of research. The uniformity of the helium abundance around the universe supports the big bang theory and the abundance of deuterium can be used to estimate the density of matter in the universe.
From about 380,000 to about 1 million years after the big bang, the universe cooled to about 3000°C (about 5000°F) and protons and electrons combined to make hydrogen atoms. Hydrogen atoms can only absorb and emit specific colors, or wavelengths, of light. The formation of atoms allowed many other wavelengths of light, wavelengths that had been interfering with the free electrons, to travel much farther than before. This change set free radiation that we can detect today. After billions of years of cooling, this cosmic background radiation is at about 3 K (-270°C/-454°F).The cosmic background radiation was first detected and identified in 1965 by American astrophysicists Arno Penzias and Robert Wilson.
The Cosmic Background Explorer (COBE) spacecraft, a project of the National Aeronautics and Space Administration (NASA), mapped the cosmic background radiation between 1989 and 1993. It verified that the distribution of intensity of the background radiation precisely matched that of matter that emits radiation because of its temperature, as predicted for the big bang theory. It also showed that cosmic background radiation is not uniform, that it varies slightly. These variations are thought to be the seeds from which galaxies and other structures in the universe grew.
Evidence indicates that the matter that scientists detect in the universe is only a small fraction of all the matter that exists. For example, observations of the speeds at which individual galaxies move within clusters of galaxies show that a great deal of unseen matter must exist to exert sufficient gravitational force to keep the clusters from flying apart. Cosmologists now think that much of the universe is dark matter—matter that has gravity but does not give off radiation that we can see or otherwise detect. One kind of dark matter theorized by scientists is cold dark matter, with slowly moving (cold) massive particles. No such particles have yet been detected, though astronomers have made up fanciful names for them, such as Weakly Interacting Massive Particles (WIMPs). Other cold dark matter could be nonradiating stars or planets, which are known as MACHOs (Massive Compact Halo Objects).
An alternative theory that explains the dark-matter model involves hot dark matter, where hot implies that the particles are moving very fast. Neutrinos, fundamental particles that travel at nearly the speed of light, are the prime example of hot dark matter. However, scientists think that the mass of a neutrino is so low that neutrinos can only account for a small portion of dark matter. If the inflationary version of big bang theory is correct, then the amount of dark matter and of whatever else might exist is just enough to bring the universe to the boundary between open and closed.
Scientists develop theoretical models to show how the universe’s structures, such as clusters of galaxies, have formed. Their models invoke hot dark matter, cold dark matter, or a mixture of the two. This unseen matter would have provided the gravitational force needed to bring large structures such as clusters of galaxies together. The theories that include dark matter match the observations, although there is no consensus on the type or types of dark matter that must be included. Supercomputers are important for making such models.
Astronomers continue to make new observations that are also interpreted within the framework of the big bang theory. No major problems with the big bang theory have been found, but scientists constantly adjust the theory to match the observed universe. In particular, a “standard model” of the big bang has been established by results from NASA's Wilkinson Microwave Anisotropy Probe (WMAP), launched in 2001 (see Cosmology). The probe studied the anisotropies, or ripples, in the temperature of cosmic background radiation at a higher resolution than COBE was capable of. These ripples indicate that regions of the young universe were very slightly hotter or cooler, by a factor of about 1/1000, than adjacent regions. WMAP’s observations suggest that the rate of expansion of the universe, called Hubble’s constant, is about 71 km/s/Mpc (kilometers per second per million parsecs, where a parsec is about 3.26 light-years). In other words, the distance between any two objects in space that are separated by a million parsecs increases by about 71 km every second in addition to any other motion they may have relative to one another. In combination with previously existing observations, this rate of expansion tells cosmologists that the universe is “flat,” though flatness here does not refer to the actual shape of the universe but rather that the geometric laws that apply to the universe match those of a flat plane.
To be flat, the universe must contain a certain amount of matter and energy, known as the critical density. The distribution of sizes of ripples detected by WMAP show that ordinary matter—like that making up objects and living things on Earth—accounts for only 4.4 percent of the critical density. Dark matter makes up an additional 23 percent. Astoundingly, the remaining 73 percent of the universe is composed of something else—a substance so mysterious that nobody knows much about it. Called “dark energy,” this substance provides the antigravity-like negative pressure that causes the universe's expansion to accelerate rather than slow down. This “accelerating universe” was detected independently by two competing groups of astronomers in the last years of the 20th century. The ideas of an accelerating universe and the existence of dark energy have caused astronomers to substantially modify previous ideas of the big bang universe.
WMAP's results also show that cosmic background radiation was set free about 380,000 years after the big bang, later than was previously thought, and that the first stars formed only 200,000 years after the big bang, earlier than anticipated. Further refinements to the big bang theory are expected from WMAP, which continues to collect data. An even more precise mission to study the beginnings of the universe, the European Space Agency’s Planck spacecraft, is scheduled to be launched in 2007.
| silkmesh wrote: |
| Big Bang
I have read many scientific theories about how the universe was created, all being very long winded theories, as if proof to the author’s high academic standings. Prof. Friedmann, William Lane Craig, John Leslie, Hawking, Penrose, Guth, Linde's, Albrecht, Steinhardt's, Tryon's and Gott have all added life to the Big Bang Cosmology question. ‘Einstein equation' that lies at the heart of the General Theory of Relativity gave power to the original Friedmann’s theory and Prof. Hawkins was dabbling with quantum maths to prove his point. I am not an expert within this field however I do have my own ideas based on what I believe to be logical facts. The first being you cannot manufacture something if you do not have the basic materials; 1. The universe exists 2. Something must have caused the creation Perhaps there is no such thing as total emptiness and emptiness cannot exist. That the very emptiness of space created the big bang as emptiness has to contain something. Maybe that the mechanisms Quantum physics are not fully understood perhaps instead of two quarks there are four; two matter quarks and two anti-matters that if all four met the set quarks then cease to exist. Would it of been possible that the big bang was caused the eruption of separating pairs of quarks spiralling outwards forming two new universes one of matter and the other of antimatter. |
a) Space is not empty and to make sense we should be talking about spacetime rather than space.
b) Emptiness is not a sensible concept to apply to pre-BB since emptiness implies space which contains nothing. Pre-BB there was NO space to be empty.
c) The composition of antimatter is well described by the standard model. Antimatter is that built from
- Antiquarks (charges of -2/3 or +1/3).
- Positively charged leptons.
- Right-handed neutrinos.
- All quarks, (charges +2/3 and -1/3).
- All negatively charged leptons.
- Left handed neutrinos.
| Quote: |
|
Perhaps both universes eventually meet and join together to create a void prior to a new rebirth. Could it be that antimatter is very dense, could it be black holes are made up of antimatter a product of the big bang; perhaps there is only one universe? Lets leave that problem to the theorist most properly someone as bright as the late Prof. Hawkins will provide an answer. |
It is theorised that matter black holes and antimatter black holes both exist and are separated by the Einstein-Rosen Bridge. More details here
| Bikerman wrote: | ||||
a) Space is not empty and to make sense we should be talking about spacetime rather than space. b) Emptiness is not a sensible concept to apply to pre-BB since emptiness implies space which contains nothing. Pre-BB there was NO space to be empty. c) The composition of antimatter is well described by the standard model. Antimatter is that built from
It is theorised that matter black holes and antimatter black holes both exist and are separated by the Einstein-Rosen Bridge. More details here |
With you all the way to here, Chris:
Bikerman>It is theorised that matter black holes and antimatter black holes both exist and are separated by the Einstein-Rosen Bridge. More details here
Yep, the early days after the advents of Planck’s quantum theory and Einstein’s General Relativity theory of matter and radiation inspired much fantasy too: some remain as interesting sci-fi.
Feynman et al’s quantum electrodynamics hinted at the final test for an alien to be made of anti-matter: “Which hand (left, right, both, neither or no hands?) does it proffer in greeting?” and signatures from reality (COBE, WMAP &c) suggest no hint of anti-matter black holes in the neighbourhood. Yet.
Although I feel pretty sure Penrose has a true mind-image of the meaning of, “The cosmological constant, λ > 0.” I still find it much easier to visualise any accelerations in expansion from the viewpoint of co-moving observers in the dimension above, e.g. Planetary weather maps are best viewed from orbit/freefall.
As a general thought, can anyone hereabouts supply links to the relevant equations to look for differences in the gravitational radiation spectrum from time ~0 predicted by Penrose (scale invariant) and Steinhardt & Turok (scale invariant), please? Bridging the shoulders of these giants feels pretty precarious right now but I am reassured that both pictures SU(10) and SU(11) seem to be pointing at the same ‘effective’ theory for us lower dimensional dwellers in crash-helmets (just in case the chaos goes twisted, again).
ed.
| newolder wrote: |
|
Feynman et al’s quantum electrodynamics hinted at the final test for an alien to be made of anti-matter: “Which hand (left, right, both, neither or no hands?) does it proffer in greeting?” and signatures from reality (COBE, WMAP &c) suggest no hint of anti-matter black holes in the neighbourhood. Yet. |
Happy to accept this correction (always happy to have input from you, especially when referencing work from one of my heros - RF).
Wow, Chris and Ed, you two better spend more time on this and create a theory. People get paid for this stuff.
I am no expert and never made any statements to that effect.
So my own input can be laught at, scorned and rubbished or can it? From the facts that have been proven about the universe by science, many inteligent men have invented a very complexed set theories, these are only theories and not facts.
I have looked at the problem logically and analectically to obtain a possible simple solution. However its up to the reader to come up with their own opinion, or to make themselves look bright by offering a few red herrings that look good but is that really clever?
I dont think any of us here are bright enough to come up with the truth with out solid facts and not use the theories of others based on a mathimatical system that has not been fully proven.
THATS WHY THE EXPERTS STATE THEORY GUYS
My own rendering is of cause my theory and note I stated PERHAPS. Guys read my articals carefully before you make statements please,
Best regards
I am no expert and never made any statements to that effect.
So my own input can be laught at, scorned and rubbished or can it? From the facts that have been proven about the universe by science, many inteligent men have invented a very complexed set theories, these are only theories and not facts.
I have looked at the problem logically and analectically to obtain a possible simple solution. However its up to the reader to come up with their own opinion, or to make themselves look bright by offering a few red herrings that look good but is that really clever?
I dont think any of us here are bright enough to come up with the truth with out solid facts and not use the theories of others based on a mathimatical system that has not been fully proven.
THATS WHY THE EXPERTS STATE THEORY GUYS
My own rendering is of cause my theory and note I stated PERHAPS. Guys read my articals carefully before you make statements please,
Best regards
| silkmesh wrote: |
| Wow, Chris and Ed, you two better spend more time on this and create a theory. People get paid for this stuff.
I am no expert and never made any statements to that effect. So my own input can be laught at, scorned and rubbished or can it? From the facts that have been proven about the universe by science, many inteligent men have invented a very complexed set theories, these are only theories and not facts. |
I was not intending to ridicule or scorn your thoughts, and am sorry if that was the impression I gave. I was merely attempting to add what I understand to be current thinking on the matter.
I would, however, urge caution with words like 'theory' and 'fact'. It is a topic which I frequently post on so I'll be brief here in pointing out the problem. Science does not deal in concept like 'truth' and the word 'fact' should be understood in that light. Science consists of theories which are backed by experiment and/or observation and constitute the best models we currently have to explain a phenomenon or set of phenomena. Talk of 'theories not facts' is misleading in that it implies that science distinguishes between the two and that one is somehow more 'solid' than the other - that is not the case. All of science is theory, but that does not imply that, as such, it is less 'true' or less understood than things we accept as fact.
PS 'Ed' is an old 'on-line' buddy who I first met on the Elmhurst science forums some time ago, and whose knowledge in these matters far exceeds my own humble musings.
I agree, but read some of the threads, where as some members have quoted theories as facts.
Its just a point.
You cannot give augument agaist someones personal theory with a well known scientific theory as if that theory is a proven fact. How ever in all fairness you can quote the theory as a theory that shows a possible incorrectness.
Best regards
Its just a point.
You cannot give augument agaist someones personal theory with a well known scientific theory as if that theory is a proven fact. How ever in all fairness you can quote the theory as a theory that shows a possible incorrectness.
Best regards
| Bikerman wrote: | ||
I was not intending to ridicule or scorn your thoughts, and am sorry if that was the impression I gave. I was merely attempting to add what I understand to be current thinking on the matter. I would, however, urge caution with words like 'theory' and 'fact'. It is a topic which I frequently post on so I'll be brief here in pointing out the problem. Science does not deal in concept like 'truth' and the word 'fact' should be understood in that light. Science consists of theories which are backed by experiment and/or observation and constitute the best models we currently have to explain a phenomenon or set of phenomena. Talk of 'theories not facts' is misleading in that it implies that science distinguishes between the two and that one is somehow more 'solid' than the other - that is not the case. All of science is theory, but that does not imply that, as such, it is less 'true' or less understood than things we accept as fact. PS 'Ed' is an old 'on-line' buddy who I first met on the Elmhurst science forums some time ago, and whose knowledge in these matters far exceeds my own humble musings. |
Chris Bikerman>… PS 'Ed' is an old 'on-line' buddy who I first met on the Elmhurst science forums some time ago, and whose knowledge in these matters far exceeds my own humble musings.
I regard this as a) a promotion; b) probably correct and c) >humbling.
a) The time before any connection was made between us two (or more), maps, conformally, to the current state of the machine.
b) Both our knowledges are subsets of what is available and mine is tiny. Yours is probably increasing at a faster rate than mine; ‘what is available’ increases very, very much faster.
c) Is it possible that I sometimes write sense?
Although STS-117 is delayed until April 2007, happy Tuesdays. ed.
Okay thinks I can follow the drift dude but lets get back to the problem
Logic reasoning.
All complex problems have simple solutions such as:
1. The universe will end and there will be a rebirth a new universe out of the ashes of the old
2. Or there are many universes and many end and new ones are born
3. No the universe will never end
Logic solution
Let’s spin a coin and save an headache
Best regards
Logic reasoning.
All complex problems have simple solutions such as:
1. The universe will end and there will be a rebirth a new universe out of the ashes of the old
2. Or there are many universes and many end and new ones are born
3. No the universe will never end
Logic solution
Let’s spin a coin and save an headache
Best regards
| silkmesh wrote: |
| Okay thinks I can follow the drift dude but lets get back to the problem
Logic reasoning. All complex problems have simple solutions such as: |
This may be reasoning but it is not logic. Where, in logic, do you find any support for the claim that all complex problems have simple solutions?
| silkmesh wrote: |
| Okay thinks I can follow the drift dude but lets get back to the problem
Logic reasoning. All complex problems have simple solutions such as: 1. The universe will end and there will be a rebirth a new universe out of the ashes of the old 2. Or there are many universes and many end and new ones are born 3. No the universe will never end Logic solution Let’s spin a coin and save an headache Best regards |
Hi silkmesh,
All problems are soluble (David Deutsch, 2006*) but inexpert philosophising always yields such circular reasoning.
Put simply, all we have to do, to make a start, is agree on the definition of the problem: i.e. what observation is to be discussed.
Next, apply the analysis methods from in the best available toolkit, e.g. those supplied by Euclid, Newton, Liebnitz, Gauss, Planck, Einstein, Minkowski, Kaluza, Klein, Schrödinger, Dirac, Veneziano, Penrose, Hawking, van t’Hooft, Steinhardt and Turok et al on a chaotic background. Collectively, these methods are held in a container known as unitary group in three dimensions, U(3).
The results are inevitable but sometimes shocking. ed.
P.S. Which of the three outcomes of tossing a coin (heads, tails, all other outcomes) would save a headache?
* http://tedblog.typepad.com/tedblog/2006/09/david_deutsch_o.html
Last edited by newolder on Wed Feb 28, 2007 2:34 pm; edited 3 times in total
| silkmesh wrote: |
| I agree, but read some of the threads, where as some members have quoted theories as facts.
Its just a point. You cannot give augument agaist someones personal theory with a well known scientific theory as if that theory is a proven fact. How ever in all fairness you can quote the theory as a theory that shows a possible incorrectness. |
No...I don't think you have yet understood the point. I'll try to explain.
a) Theory - model supported by observation, experiment and subjected to peer review. Theory explains 'fact'.
b) Fact - an observation that has been confirmed repeatedly and is accepted as true (although its truth is never final)
c) Someone's personal theory - not a theory at all, at best a hypothesis unless it conforms to point a, and most often mere speculation.
I hope that helps clarify...
0,1,2,many,many1,many2,many many....
The solution is always very simple, but the finder normally makes the solution difficult to understand, normally to show that he or she is an expert.
The actual process of finding a solution can be an headache. In this case it’s not just a point of bathing in a hot bath a finalizing with expressive shout of eureka. As there is no true proven facts only theory models, ideas and a set of mathematic equations that could be flawed. I would really want to see the water be displaced before working out an excepted answer that would look feasible.
Tossing a coin sounds good to me at present, as the problem at hand can not be solved with out solid proof. However in reality I feel that a Logic possible answer is more acceptable to my own understanding and that’s the answer I have used in my book.
You all keep arguing on the issue but please add logic thought to your conclusions and try to be open minded and not use the views of others as they could be wrong. That’s the trouble with any science today there is not enough thought to the what if's only to the so call scientific rules in this case physics. Some of the rules are erroneous!
Of course my own possible answer could be wrong, I dont really care as I am only interested in enviromental brainwashing, culture, religion, politics and how this so called civilized society on earth can be at peace with each other.
Best regards
The actual process of finding a solution can be an headache. In this case it’s not just a point of bathing in a hot bath a finalizing with expressive shout of eureka. As there is no true proven facts only theory models, ideas and a set of mathematic equations that could be flawed. I would really want to see the water be displaced before working out an excepted answer that would look feasible.
Tossing a coin sounds good to me at present, as the problem at hand can not be solved with out solid proof. However in reality I feel that a Logic possible answer is more acceptable to my own understanding and that’s the answer I have used in my book.
You all keep arguing on the issue but please add logic thought to your conclusions and try to be open minded and not use the views of others as they could be wrong. That’s the trouble with any science today there is not enough thought to the what if's only to the so call scientific rules in this case physics. Some of the rules are erroneous!
Of course my own possible answer could be wrong, I dont really care as I am only interested in enviromental brainwashing, culture, religion, politics and how this so called civilized society on earth can be at peace with each other.
Best regards
| silkmesh wrote: |
| The solution is always very simple, but the finder normally makes the solution difficult to understand, normally to show that he or she is an expert. |
| Quote: |
| The actual process of finding a solution can be an headache. In this case it’s not just a point of bathing in a hot bath a finalizing with expressive shout of eureka. As there is no true proven facts only theory models, ideas and a set of mathematic equations that could be flawed. I would really want to see the water be displaced before working out an excepted answer that would look feasible. |
You consistently miss the point which I have been trying to gently introduce into your thinking. 'Proven facts' is a non-science concept. The point is
<lecture mode on>
No explanation of an observation can be said to be 'true' regardless of how many times it is confirmed by repeats. The simple example is
observation: 'the Sun has risen every morning for billions of years
theory: the Sun will rise tomorrow.
Validity: invalid. One day the Sun will certainly not do so.
This is known as the problem of induction and is the central reason why science does not deal in words like 'proven facts'. The issue was dealt with by Popper's notion of 'refutability' as the distinction between science and non-science.
<lecture mode off>
| Quote: |
|
Tossing a coin sounds good to me at present, as the problem at hand can not be solved with out solid proof. However in reality I feel that a Logic possible answer is more acceptable to my own understanding and that’s the answer I have used in my book. |
| Quote: |
| You all keep arguing on the issue but please add logic thought to your conclusions and try to be open minded and not use the views of others as they could be wrong. That’s the trouble with any science today there is not enough thought to the what if's only to the so call scientific rules in this case physics. Some of the rules are erroneous!
|
| silkmesh wrote: |
| ...
You all keep arguing on the issue but please add logic thought to your conclusions and try to be open minded and not use the views of others as they could be wrong. That’s the trouble with any science today there is not enough thought to the what if's only to the so call scientific rules in this case physics. Some of the rules are erroneous! ... |
Axiomatic logic was shown to be an inadequate tool of explanation by Russell and Godel in the early 20th century: any system of logic can be shown to produce statements to the effect: "This statement is true if, and only if, this statement is false." (See also, The Bayesian approach*.)
Which of the 'rules' are a) erroneous and b) broken by modern physics and mathematics, please? Note: Your answer is to include relevant urls, please. ed.
* http://www.bayesian.org/
Ok
Ill let you have the last word.
What URLs you after pal?
Is this a case of pistols for two and coffee for one?
Ill let you have the last word.
What URLs you after pal?
Is this a case of pistols for two and coffee for one?
| silkmesh wrote: |
| Ok
Ill let you have the last word. What URLs you after pal? Is this a case of pistols for two and coffee for one? |
?
To repeat, the questions are, "Which 'rules' are a) erroneous and b) broken by modern physics and mathematics?"
If you have no urls to hand, ISBNs will suffice.
The next word is with you.
ed.
PS ed <> pal.
| Quote: |
|
Please use quote tags, identify the source and add a little original thought when copying and pasting the work of another. Big Bang Theory, currently accepted explanation of the beginning of the universe. The big bang theory proposes that the universe was once extremely compact, dense, and hot. Some original event, a cosmic explosion called the big bang, occurred about 13.7 billion years ago, and the universe has since been expanding and cooling. The theory is based on the mathematical equations, known as the field equations, of the general theory of relativity set forth in 1915 by Albert Einstein. In 1922 Russian physicist Alexander Friedmann provided a set of solutions to the field equations. These solutions have served as the framework for much of the current theoretical work on the big bang theory. American astronomer Edwin Hubble provided some of the greatest supporting evidence for the theory with his 1929 discovery that the light of distant galaxies was universally shifted toward the red end of the spectrum (see Redshift). Once “tired light” theories—that light slowly loses energy naturally, becoming more red over time—were dismissed, this shift proved that the galaxies were moving away from each other. Hubble found that galaxies farther away were moving away proportionally faster, showing that the universe is expanding uniformly. However, the universe’s initial state was still unknown In the 1940s Russian-American physicist George Gamow worked out a theory that fit with Friedmann’s solutions in which the universe expanded from a hot, dense state. In 1950 British astronomer Fred Hoyle, in support of his own opposing steady-state theory, referred to Gamow’s theory as a mere “big bang,” but the name stuck. Indeed, a contest in the 1990s by Sky & Telescope magazine to find a better (perhaps more dignified) name did not produce one. The overall framework of the big bang theory came out of solutions to Einstein’s general relativity field equations and remains unchanged, but various details of the theory are still being modified today. Einstein himself initially believed that the universe was static. When his equations seemed to imply that the universe was expanding or contracting, Einstein added a constant term to cancel out the expansion or contraction of the universe. When the expansion of the universe was later discovered, Einstein stated that introducing this “cosmological constant” had been a mistake. After Einstein’s work of 1917, several scientists, including the abbé Georges Lemaître in Belgium, Willem de Sitter in Holland, and Alexander Friedmann in Russia, succeeded in finding solutions to Einstein’s field equations. The universes described by the different solutions varied. De Sitter’s model had no matter in it. This model is actually not a bad approximation since the average density of the universe is extremely low. Lemaître’s universe expanded from a “primeval atom.” Friedmann’s universe also expanded from a very dense clump of matter, but did not involve the cosmological constant. These models explained how the universe behaved shortly after its creation, but there was still no satisfactory explanation for the beginning of the universe. In the 1940s George Gamow was joined by his students Ralph Alpher and Robert Herman in working out details of Friedmann’s solutions to Einstein’s theory. They expanded on Gamow’s idea that the universe expanded from a primordial state of matter called ylem consisting of protons, neutrons, and electrons in a sea of radiation. They theorized the universe was very hot at the time of the big bang (the point at which the universe explosively expanded from its primordial state), since elements heavier than hydrogen can be formed only at a high temperature. Alpher and Hermann predicted that radiation from the big bang should still exist. Cosmic background radiation roughly corresponding to the temperature predicted by Gamow’s team was detected in the 1960s, further supporting the big bang theory, though the work of Alpher, Herman, and Gamow had been forgotten. The big bang theory seeks to explain what happened at or soon after the beginning of the universe. Scientists can now model the universe back to 10-43 seconds after the big bang. For the time before that moment, the classical theory of gravity is no longer adequate. Scientists are searching for a theory that merges gravity (as explained by Einstein's general theory of relativity) and quantum mechanics but have not found one yet. Many scientists have hope that string theory, also known as M-theory, will tie together gravity and quantum mechanics and help scientists explore further back in time (see Physics: Unified Field Theory). Because scientists cannot look back in time beyond that early epoch, the actual big bang is hidden from them. There is no way at present to detect the origin of the universe. Further, the big bang theory does not explain what existed before the big bang. It may be that time itself began at the big bang, so that it makes no sense to discuss what happened “before” the big bang. According to the big bang theory, the universe expanded rapidly in its first microseconds. A single force existed at the beginning of the universe, and as the universe expanded and cooled, this force separated into those we know today: gravity, electromagnetism, the strong nuclear force, and the weak nuclear force. A theory called the electroweak theory now provides a unified explanation of electromagnetism and the weak nuclear force theory (see Unified Field Theory). Physicists are now searching for a grand unification theory to also incorporate the strong nuclear force. String theory seeks to incorporate the force of gravity with the other three forces, providing a theory of everything (TOE). One widely accepted version of big bang theory includes the idea of inflation. In this model, the universe expanded much more rapidly at first, to about 1050 times its original size in the first 10-32 second, then slowed its expansion. The theory was advanced in the 1980s by American cosmologist Alan Guth and elaborated upon by American astronomer Paul Steinhardt, Russian American scientist Andrei Linde, and British astronomer Andreas Albrecht. The inflationary universe theory (see Inflationary Theory) solves a number of problems of cosmology. For example, it shows that the universe now appears close to the type of flat space described by the laws of Euclid’s geometry: We see only a tiny region of the original universe, similar to the way we do not notice the curvature of the earth because we see only a small part of it. The inflationary universe also shows why the universe appears so homogeneous. If the universe we observe was inflated from some small, original region, it is not surprising that it appears uniform. Once the expansion of the initial inflationary era ended, the universe continued to expand more slowly. The inflationary model predicts that the universe is on the boundary between being open and closed. If the universe is open, it will keep expanding forever. If the universe is closed, the expansion of the universe will eventually stop and the universe will begin contracting until it collapses. Whether the universe is open or closed depends on the density, or concentration of mass, in the universe. If the universe is dense enough, it is closed. The universe cooled as it expanded. After about one second, protons formed. In the following few minutes—often referred to as the “first three minutes”—combinations of protons and neutrons formed the isotope of hydrogen known as deuterium as well as some of the other light elements, principally helium, as well as some lithium, beryllium, and boron. The study of the distribution of deuterium, helium, and the other light elements is now a major field of research. The uniformity of the helium abundance around the universe supports the big bang theory and the abundance of deuterium can be used to estimate the density of matter in the universe. From about 380,000 to about 1 million years after the big bang, the universe cooled to about 3000°C (about 5000°F) and protons and electrons combined to make hydrogen atoms. Hydrogen atoms can only absorb and emit specific colors, or wavelengths, of light. The formation of atoms allowed many other wavelengths of light, wavelengths that had been interfering with the free electrons, to travel much farther than before. This change set free radiation that we can detect today. After billions of years of cooling, this cosmic background radiation is at about 3 K (-270°C/-454°F).The cosmic background radiation was first detected and identified in 1965 by American astrophysicists Arno Penzias and Robert Wilson. The Cosmic Background Explorer (COBE) spacecraft, a project of the National Aeronautics and Space Administration (NASA), mapped the cosmic background radiation between 1989 and 1993. It verified that the distribution of intensity of the background radiation precisely matched that of matter that emits radiation because of its temperature, as predicted for the big bang theory. It also showed that cosmic background radiation is not uniform, that it varies slightly. These variations are thought to be the seeds from which galaxies and other structures in the universe grew. Evidence indicates that the matter that scientists detect in the universe is only a small fraction of all the matter that exists. For example, observations of the speeds at which individual galaxies move within clusters of galaxies show that a great deal of unseen matter must exist to exert sufficient gravitational force to keep the clusters from flying apart. Cosmologists now think that much of the universe is dark matter—matter that has gravity but does not give off radiation that we can see or otherwise detect. One kind of dark matter theorized by scientists is cold dark matter, with slowly moving (cold) massive particles. No such particles have yet been detected, though astronomers have made up fanciful names for them, such as Weakly Interacting Massive Particles (WIMPs). Other cold dark matter could be nonradiating stars or planets, which are known as MACHOs (Massive Compact Halo Objects). An alternative theory that explains the dark-matter model involves hot dark matter, where hot implies that the particles are moving very fast. Neutrinos, fundamental particles that travel at nearly the speed of light, are the prime example of hot dark matter. However, scientists think that the mass of a neutrino is so low that neutrinos can only account for a small portion of dark matter. If the inflationary version of big bang theory is correct, then the amount of dark matter and of whatever else might exist is just enough to bring the universe to the boundary between open and closed. Scientists develop theoretical models to show how the universe’s structures, such as clusters of galaxies, have formed. Their models invoke hot dark matter, cold dark matter, or a mixture of the two. This unseen matter would have provided the gravitational force needed to bring large structures such as clusters of galaxies together. The theories that include dark matter match the observations, although there is no consensus on the type or types of dark matter that must be included. Supercomputers are important for making such models. Astronomers continue to make new observations that are also interpreted within the framework of the big bang theory. No major problems with the big bang theory have been found, but scientists constantly adjust the theory to match the observed universe. In particular, a “standard model” of the big bang has been established by results from NASA's Wilkinson Microwave Anisotropy Probe (WMAP), launched in 2001 (see Cosmology). The probe studied the anisotropies, or ripples, in the temperature of cosmic background radiation at a higher resolution than COBE was capable of. These ripples indicate that regions of the young universe were very slightly hotter or cooler, by a factor of about 1/1000, than adjacent regions. WMAP’s observations suggest that the rate of expansion of the universe, called Hubble’s constant, is about 71 km/s/Mpc (kilometers per second per million parsecs, where a parsec is about 3.26 light-years). In other words, the distance between any two objects in space that are separated by a million parsecs increases by about 71 km every second in addition to any other motion they may have relative to one another. In combination with previously existing observations, this rate of expansion tells cosmologists that the universe is “flat,” though flatness here does not refer to the actual shape of the universe but rather that the geometric laws that apply to the universe match those of a flat plane. To be flat, the universe must contain a certain amount of matter and energy, known as the critical density. The distribution of sizes of ripples detected by WMAP show that ordinary matter—like that making up objects and living things on Earth—accounts for only 4.4 percent of the critical density. Dark matter makes up an additional 23 percent. Astoundingly, the remaining 73 percent of the universe is composed of something else—a substance so mysterious that nobody knows much about it. Called “dark energy,” this substance provides the antigravity-like negative pressure that causes the universe's expansion to accelerate rather than slow down. This “accelerating universe” was detected independently by two competing groups of astronomers in the last years of the 20th century. The ideas of an accelerating universe and the existence of dark energy have caused astronomers to substantially modify previous ideas of the big bang universe. WMAP's results also show that cosmic background radiation was set free about 380,000 years after the big bang, later than was previously thought, and that the first stars formed only 200,000 years after the big bang, earlier than anticipated. Further refinements to the big bang theory are expected from WMAP, which continues to collect data. An even more precise mission to study the beginnings of the universe, the European Space Agency’s Planck spacecraft, is scheduled to be launched in 2007. |
| silkmesh wrote: |
| Big Bang Theory, currently accepted explanation of the beginning of the universe. The big bang theory proposes that the universe was once extremely compact, dense, and hot. Some original event, a cosmic explosion called the big bang, occurred about 13.7 billion years ago, and the universe has since been expanding and cooling.
The theory is based on the mathematical equations, known as the field equations, of the general theory of relativity set forth in 1915 by Albert Einstein. In 1922 Russian physicist Alexander Friedmann provided a set of solutions to the field equations. These solutions have served as the framework for much of the current theoretical work on the big bang theory. American astronomer Edwin Hubble provided some of the greatest supporting evidence for the theory with his 1929 discovery that the light of distant galaxies was universally shifted toward the red end of the spectrum (see Redshift). Once “tired light” theories—that light slowly loses energy naturally, becoming more red over time—were dismissed, this shift proved that the galaxies were moving away from each other. Hubble found that galaxies farther away were moving away proportionally faster, showing that the universe is expanding uniformly. However, the universe’s initial state was still unknown In the 1940s Russian-American physicist George Gamow worked out a theory that fit with Friedmann’s solutions in which the universe expanded from a hot, dense state. In 1950 British astronomer Fred Hoyle, in support of his own opposing steady-state theory, referred to Gamow’s theory as a mere “big bang,” but the name stuck. Indeed, a contest in the 1990s by Sky & Telescope magazine to find a better (perhaps more dignified) name did not produce one. The overall framework of the big bang theory came out of solutions to Einstein’s general relativity field equations and remains unchanged, but various details of the theory are still being modified today. Einstein himself initially believed that the universe was static. When his equations seemed to imply that the universe was expanding or contracting, Einstein added a constant term to cancel out the expansion or contraction of the universe. When the expansion of the universe was later discovered, Einstein stated that introducing this “cosmological constant” had been a mistake. After Einstein’s work of 1917, several scientists, including the abbé Georges Lemaître in Belgium, Willem de Sitter in Holland, and Alexander Friedmann in Russia, succeeded in finding solutions to Einstein’s field equations. The universes described by the different solutions varied. De Sitter’s model had no matter in it. This model is actually not a bad approximation since the average density of the universe is extremely low. Lemaître’s universe expanded from a “primeval atom.” Friedmann’s universe also expanded from a very dense clump of matter, but did not involve the cosmological constant. These models explained how the universe behaved shortly after its creation, but there was still no satisfactory explanation for the beginning of the universe. In the 1940s George Gamow was joined by his students Ralph Alpher and Robert Herman in working out details of Friedmann’s solutions to Einstein’s theory. They expanded on Gamow’s idea that the universe expanded from a primordial state of matter called ylem consisting of protons, neutrons, and electrons in a sea of radiation. They theorized the universe was very hot at the time of the big bang (the point at which the universe explosively expanded from its primordial state), since elements heavier than hydrogen can be formed only at a high temperature. Alpher and Hermann predicted that radiation from the big bang should still exist. Cosmic background radiation roughly corresponding to the temperature predicted by Gamow’s team was detected in the 1960s, further supporting the big bang theory, though the work of Alpher, Herman, and Gamow had been forgotten. The big bang theory seeks to explain what happened at or soon after the beginning of the universe. Scientists can now model the universe back to 10-43 seconds after the big bang. For the time before that moment, the classical theory of gravity is no longer adequate. Scientists are searching for a theory that merges gravity (as explained by Einstein's general theory of relativity) and quantum mechanics but have not found one yet. Many scientists have hope that string theory, also known as M-theory, will tie together gravity and quantum mechanics and help scientists explore further back in time (see Physics: Unified Field Theory). Because scientists cannot look back in time beyond that early epoch, the actual big bang is hidden from them. There is no way at present to detect the origin of the universe. Further, the big bang theory does not explain what existed before the big bang. It may be that time itself began at the big bang, so that it makes no sense to discuss what happened “before” the big bang. According to the big bang theory, the universe expanded rapidly in its first microseconds. A single force existed at the beginning of the universe, and as the universe expanded and cooled, this force separated into those we know today: gravity, electromagnetism, the strong nuclear force, and the weak nuclear force. A theory called the electroweak theory now provides a unified explanation of electromagnetism and the weak nuclear force theory (see Unified Field Theory). Physicists are now searching for a grand unification theory to also incorporate the strong nuclear force. String theory seeks to incorporate the force of gravity with the other three forces, providing a theory of everything (TOE). One widely accepted version of big bang theory includes the idea of inflation. In this model, the universe expanded much more rapidly at first, to about 1050 times its original size in the first 10-32 second, then slowed its expansion. The theory was advanced in the 1980s by American cosmologist Alan Guth and elaborated upon by American astronomer Paul Steinhardt, Russian American scientist Andrei Linde, and British astronomer Andreas Albrecht. The inflationary universe theory (see Inflationary Theory) solves a number of problems of cosmology. For example, it shows that the universe now appears close to the type of flat space described by the laws of Euclid’s geometry: We see only a tiny region of the original universe, similar to the way we do not notice the curvature of the earth because we see only a small part of it. The inflationary universe also shows why the universe appears so homogeneous. If the universe we observe was inflated from some small, original region, it is not surprising that it appears uniform. Once the expansion of the initial inflationary era ended, the universe continued to expand more slowly. The inflationary model predicts that the universe is on the boundary between being open and closed. If the universe is open, it will keep expanding forever. If the universe is closed, the expansion of the universe will eventually stop and the universe will begin contracting until it collapses. Whether the universe is open or closed depends on the density, or concentration of mass, in the universe. If the universe is dense enough, it is closed. The universe cooled as it expanded. After about one second, protons formed. In the following few minutes—often referred to as the “first three minutes”—combinations of protons and neutrons formed the isotope of hydrogen known as deuterium as well as some of the other light elements, principally helium, as well as some lithium, beryllium, and boron. The study of the distribution of deuterium, helium, and the other light elements is now a major field of research. The uniformity of the helium abundance around the universe supports the big bang theory and the abundance of deuterium can be used to estimate the density of matter in the universe. From about 380,000 to about 1 million years after the big bang, the universe cooled to about 3000°C (about 5000°F) and protons and electrons combined to make hydrogen atoms. Hydrogen atoms can only absorb and emit specific colors, or wavelengths, of light. The formation of atoms allowed many other wavelengths of light, wavelengths that had been interfering with the free electrons, to travel much farther than before. This change set free radiation that we can detect today. After billions of years of cooling, this cosmic background radiation is at about 3 K (-270°C/-454°F).The cosmic background radiation was first detected and identified in 1965 by American astrophysicists Arno Penzias and Robert Wilson. The Cosmic Background Explorer (COBE) spacecraft, a project of the National Aeronautics and Space Administration (NASA), mapped the cosmic background radiation between 1989 and 1993. It verified that the distribution of intensity of the background radiation precisely matched that of matter that emits radiation because of its temperature, as predicted for the big bang theory. It also showed that cosmic background radiation is not uniform, that it varies slightly. These variations are thought to be the seeds from which galaxies and other structures in the universe grew. Evidence indicates that the matter that scientists detect in the universe is only a small fraction of all the matter that exists. For example, observations of the speeds at which individual galaxies move within clusters of galaxies show that a great deal of unseen matter must exist to exert sufficient gravitational force to keep the clusters from flying apart. Cosmologists now think that much of the universe is dark matter—matter that has gravity but does not give off radiation that we can see or otherwise detect. One kind of dark matter theorized by scientists is cold dark matter, with slowly moving (cold) massive particles. No such particles have yet been detected, though astronomers have made up fanciful names for them, such as Weakly Interacting Massive Particles (WIMPs). Other cold dark matter could be nonradiating stars or planets, which are known as MACHOs (Massive Compact Halo Objects). An alternative theory that explains the dark-matter model involves hot dark matter, where hot implies that the particles are moving very fast. Neutrinos, fundamental particles that travel at nearly the speed of light, are the prime example of hot dark matter. However, scientists think that the mass of a neutrino is so low that neutrinos can only account for a small portion of dark matter. If the inflationary version of big bang theory is correct, then the amount of dark matter and of whatever else might exist is just enough to bring the universe to the boundary between open and closed. Scientists develop theoretical models to show how the universe’s structures, such as clusters of galaxies, have formed. Their models invoke hot dark matter, cold dark matter, or a mixture of the two. This unseen matter would have provided the gravitational force needed to bring large structures such as clusters of galaxies together. The theories that include dark matter match the observations, although there is no consensus on the type or types of dark matter that must be included. Supercomputers are important for making such models. Astronomers continue to make new observations that are also interpreted within the framework of the big bang theory. No major problems with the big bang theory have been found, but scientists constantly adjust the theory to match the observed universe. In particular, a “standard model” of the big bang has been established by results from NASA's Wilkinson Microwave Anisotropy Probe (WMAP), launched in 2001 (see Cosmology). The probe studied the anisotropies, or ripples, in the temperature of cosmic background radiation at a higher resolution than COBE was capable of. These ripples indicate that regions of the young universe were very slightly hotter or cooler, by a factor of about 1/1000, than adjacent regions. WMAP’s observations suggest that the rate of expansion of the universe, called Hubble’s constant, is about 71 km/s/Mpc (kilometers per second per million parsecs, where a parsec is about 3.26 light-years). In other words, the distance between any two objects in space that are separated by a million parsecs increases by about 71 km every second in addition to any other motion they may have relative to one another. In combination with previously existing observations, this rate of expansion tells cosmologists that the universe is “flat,” though flatness here does not refer to the actual shape of the universe but rather that the geometric laws that apply to the universe match those of a flat plane. To be flat, the universe must contain a certain amount of matter and energy, known as the critical density. The distribution of sizes of ripples detected by WMAP show that ordinary matter—like that making up objects and living things on Earth—accounts for only 4.4 percent of the critical density. Dark matter makes up an additional 23 percent. Astoundingly, the remaining 73 percent of the universe is composed of something else—a substance so mysterious that nobody knows much about it. Called “dark energy,” this substance provides the antigravity-like negative pressure that causes the universe's expansion to accelerate rather than slow down. This “accelerating universe” was detected independently by two competing groups of astronomers in the last years of the 20th century. The ideas of an accelerating universe and the existence of dark energy have caused astronomers to substantially modify previous ideas of the big bang universe. WMAP's results also show that cosmic background radiation was set free about 380,000 years after the big bang, later than was previously thought, and that the first stars formed only 200,000 years after the big bang, earlier than anticipated. Further refinements to the big bang theory are expected from WMAP, which continues to collect data. An even more precise mission to study the beginnings of the universe, the European Space Agency’s Planck spacecraft, is scheduled to be launched in 2007. |
A fine summary of 20th century physics.
The Planck telescope, Newsletter #8, is here :: http://www.rssd.esa.int/SA/PLANCK/docs/Newsletters/PlanckNewsletter8.pdf
Launch is still some time away…
If you wish to update your interest, Neil Turok’s recent publication list is a good start*. The superstring revolution began in 1998, iirc.
And the Penrose World Tour of 2006-2007** is worth keeping an open eye out for too.
Cheers again, ed.
* http://arxiv.org/find/hep-th/1/au:+turok/0/1/0/all/0/1
** http://www.bnl.gov/video/lectures.asp "Before the Big Bang: a novel solution to a deep cosmological puzzle."
| newolder wrote: | ||
A fine summary of 20th century physics. |
Yes. A shame that it was plagiarised.
Oooppss! ed. 
Last edited by newolder on Sat Mar 03, 2007 2:01 am; edited 1 time in total
Last edited by newolder on Sat Mar 03, 2007 2:01 am; edited 1 time in total
| newolder wrote: | ||||||
Ah! Encarta, if i read your url correctly, Indi? I'm sure they'd pursue silkmesh further, if they knew... ed. |
No the source that Encarta used. All copyright observed (Newzealand reaseacher, published in a newzealand peridical)
But now let look at my argument and stop getting bitchy.
But now let look at my argument and stop getting bitchy.
| Quote: |
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Quote tags are required anytime you are pasting an article! Another Creation Theory Bites the Dust By Stephen Knapp As a subscriber to the Vedic description of a Divinely guided process of |