I read a book with the following review of it
In this fascinating book, the renowned astrophysicist J. Richard Gott leads time travel out of the world of H. G. Wells and into the realm of scientific possibility. Building on theories posited by Einstein and advanced.
What do you guys think is it possible to travel in time
Can't really give any qualified opinion on the subject, but it is neat to think that if you look into space through a telescope, you're looking back in time 
If time travel does become available, it is very likely that you won't be able to travel any further backwards than the time when the machine was first turned on. That would be in the extremely far future anyway though.
I would look for communication through time much sooner though. It is easier to send information than living people. (In fact, I'm working on a scheme to do just that...)
Could you elaborate? I'm not sure why you say you could go no further back in time than when the machine was switched on?
Also what is the fastest we could send information and how would you redirect it backwards?
| chasbeen wrote: |
Could you elaborate? I'm not sure why you say you could go no further back in time than when the machine was switched on?
Also what is the fastest we could send information and how would you redirect it backwards? |
It is likely that you would have to have a sending and a receiving end of the machine, and if you wanted to go back further than when it was first activated, there would be no receiving end.
The fastest possible would probably be about the speed of a fiber-optic cable, per connection. At first it would be very slow though. The first prototype I build will probably work only in 1 byte per 8 seconds. These devices would also have the limit of not going further back than when the receiving end was turned on.
How? I'm afraid I won't share that. Since it would be such a groundbreaking invention (making possible computers that finish the computation before you put in the request for it, among other things), I want to make sure I get the patent rights. Even if nobody here seals it, you only have 1 year from the time the idea is 'published' (on a website counts) to get a patent filed.The fastest we can send information is c (speed of light). There are theoretical models which use Relativistic Frame Dragging to increase this (by moving the frame of reference as well as the information signal) but these normally rely on huge gravity sources (spinning black holes). A US physicist called Ron Mallett has proposed the same idea (frame dragging) but using high energy laser beams instead of gravity to 'drag' spacetime.
The physicists I know are very sceptical about the idea.
http://en.wikipedia.org/wiki/Ronald_Mallett
The other proposal for time travel that makes scientific sense, if not practical sense, involves wormholes. Assuming they exist, and can be formed at will, then the problem is that they would be inherently unstable and would require all sorts of exotic matter to keep open.
Most physicists think this is science fiction.
All the other proposals I have seen are pseudo-scientific claptrap - often based around misunderstandings of quantum physics (specifically quantum entanglement). | Bikerman wrote: |
The fastest we can send information is c (speed of light). There are theoretical models which use Relativistic Frame Dragging to increase this (by moving the frame of reference as well as the information signal) but these normally rely on huge gravity sources (spinning black holes). A US physicist called Ron Mallett has proposed the same idea (frame dragging) but using high energy laser beams instead of gravity to 'drag' spacetime.
The physicists I know are very sceptical about the idea.
http://en.wikipedia.org/wiki/Ronald_Mallett
The other proposal for time travel that makes scientific sense, if not practical sense, involves wormholes. Assuming they exist, and can be formed at will, then the problem is that they would be inherently unstable and would require all sorts of exotic matter to keep open.
Most physicists think this is science fiction.
All the other proposals I have seen are pseudo-scientific claptrap - often based around misunderstandings of quantum physics (specifically quantum entanglement). |
I agree about the psedo scientific claptrap
But
what about this
1. A team of researchers from the Ecole Polytechnique Fédérale de Lausanne (EPFL) has successfully demonstrated, for the first time, that it is possible to control the speed of light – both slowing it down and speeding it up – in an optical fiber, using off-the-shelf instrumentation in normal environmental conditions. Their results, to be published in the August 22 issue of Applied Physics Letters, could have implications that range from optical computing to the fiber-optic telecommunications industry.
REF: http://www.eurekalert.org/pub_releases/2005-08/epfd-ltt081905.phpThe only thing new here is the technology, not the science. Scientists have been able to do this for a long time - the difference is that this group are doing it cheaply using off-the shelf kit. It has no implications for time travel since information can still not be transmitted faster than c (all the scientists are doing is increasing the phase velocity beyond c - that carries no information).
eg. In the following image the red dot is the phase velocity and the green dots are the group velocities which actually carry information.
(source - http://en.wikipedia.org/wiki/Group_velocity) Further to Bikerman's post:-
If you use a wormhole (should that actually be possible) then you still have the problem of travelling to the mouth, and from the other end when you have passed through.
As far as I am aware, a wormhole would collapse if anything entered. Some kind of exotic matter would be needed to keep it stable.
With regard to time travel machines, I've just had a horrible thought. What if time travel technology was developed by Microsoft? "You have just crashed into Napoleon. Please re-boot for this change to take effect" My guess is that time travel has too many complications associated with it to work. Even if it works, what happens if people go back in time and change things, which lead to a different future?
^The concept of multiple universes would make that sort of thing make perfect sense.
Of course impossible. I mean, even though you can travel across the time, you can't leave it.
If you go forwards 1000 years, you are just killing yourself. Old to die.
yes, it is possible. TIME ELONGATION is possible, the impossible thing is It is hard to speed up near the velocity of light. You need lot of energy for that.
I don't think it possible since no one living in the future is able to come back to visit us.
| takashiro wrote: |
| I don't think it possible since no one living in the future is able to come back to visit us. |
Maybe they are visiting us but you can't see them. It's just an option 
Well, If anyone could make it in a future, I apreciate that tell me how... But, I really dont think in that as a possibility
| SlideR.nl wrote: |
| takashiro wrote: | | I don't think it possible since no one living in the future is able to come back to visit us. |
Maybe they are visiting us but you can't see them. It's just an option |
Perhaps they are visiting us, but as soon as they show up, the universe splits into two: one where they came back and one where they didn't. We're in a 'didn't' universe.
(Splitting that way clears up paradoxes in which the time traveler makes it impossible, one way or another, for him to be there. It also conveniently explains why we don't see time travelers.) | takashiro wrote: |
| I don't think it possible since no one living in the future is able to come back to visit us. |
Good point! but time travel is not something that is simply explained by all these nutjobs you hear about. You cant Go BACK IN TIME! like the movie "back to the future". So they cant visit us.
But we could visit them.
Time depends wholly on the speed of light. (No Flux capacitors needed) the problem with sending a human body through time is that at the speed of light, they would become MUSH by the time you've traveled 100 years. Also Acceleration (as we could travel at these speeds) we just dont have the power to do it. you'd need a million gigawatt's of energy.
I work at a lab, and my theory is that we should be able to accelerate outside an object while simultaneously de-accelerating within it. (so we dont turn to mush) | kristi01 wrote: |
| I work at a lab, and my theory is that we should be able to accelerate outside an object while simultaneously de-accelerating within it. (so we dont turn to mush) |
That makes no sense to me - you will have to explain further.. | Bikerman wrote: |
| kristi01 wrote: | | I work at a lab, and my theory is that we should be able to accelerate outside an object while simultaneously de-accelerating within it. (so we dont turn to mush) |
That makes no sense to me - you will have to explain further.. |
Imagine traveling in a plane. How fast are you travelling?
Now imagine travelling 10 times that speed. basically your body cant take the speed. you'd disintegrate into millions of pieces. its not a matter of traveling into the future and getting old. your body just cant be hurtling through space at the speed of light, with the expectation of coming out of it alive.
Now. if you were trapped in a bubble that was unaffected to the speed, in other words- inside the bubble you were not accelerating. but on the outside the bubble was accelerating (at the speed of light) | kristi01 wrote: |
| Bikerman wrote: | | kristi01 wrote: | | I work at a lab, and my theory is that we should be able to accelerate outside an object while simultaneously de-accelerating within it. (so we dont turn to mush) |
That makes no sense to me - you will have to explain further.. |
Imagine traveling in a plane. How fast are you travelling?
Now imagine travelling 10 times that speed. basically your body cant take the speed. you'd disintegrate into millions of pieces. its not a matter of traveling into the future and getting old. your body just cant be hurtling through space at the speed of light, with the expectation of coming out of it alive.
Now. if you were trapped in a bubble that was unaffected to the speed, in other words- inside the bubble you were not accelerating. but on the outside the bubble was accelerating (at the speed of light) |
No, I think you have a few misconceptions. Take the plane, for example. A typical speed might be 500mph. The shuttle travels at about 24,000 mph. No problem.
The problem is acceleration (ie getting up to cruising speed). The human body can't cope with much more than 2-3g over a sustained period. That need not be a problem, however, since a constant 2g acceleration will soon have you travelling at fantastic speeds.
You cannot 'accelerate at the speed of light' - acceleration is the rate of change of velocity.
The other problem, of course, is relativity. That means you can never actually get to c (speed of light). That itself need not be a problem because as you get close then time-dilation kicks in and you can cover fantastic distances in a relatively short time (subjective time).
The major problem, therefore, is sustaining acceleration for long periods of time - that is why we need different technologies to the current rockets (which soon run out of fuel).
I don't know what lab you are working at, but I hope they are not designing anything I might travel in soon..... | Bikerman wrote: |
| kristi01 wrote: | | Bikerman wrote: | | kristi01 wrote: | | I work at a lab, and my theory is that we should be able to accelerate outside an object while simultaneously de-accelerating within it. (so we dont turn to mush) |
That makes no sense to me - you will have to explain further.. |
Imagine traveling in a plane. How fast are you travelling?
Now imagine travelling 10 times that speed. basically your body cant take the speed. you'd disintegrate into millions of pieces. its not a matter of traveling into the future and getting old. your body just cant be hurtling through space at the speed of light, with the expectation of coming out of it alive.
Now. if you were trapped in a bubble that was unaffected to the speed, in other words- inside the bubble you were not accelerating. but on the outside the bubble was accelerating (at the speed of light) |
No, I think you have a few misconceptions. Take the plane, for example. A typical speed might be 500mph. The shuttle travels at about 24,000 mph. No problem.
The problem is acceleration (ie getting up to cruising speed). The human body can't cope with much more than 2-3g over a sustained period. That need not be a problem, however, since a constant 2g acceleration will soon have you travelling at fantastic speeds.
You cannot 'accelerate at the speed of light' - acceleration is the rate of change of velocity.
The other problem, of course, is relativity. That means you can never actually get to c (speed of light). That itself need not be a problem because as you get close then time-dilation kicks in and you can cover fantastic distances in a relatively short time (subjective time).
The major problem, therefore, is sustaining acceleration for long periods of time - that is why we need different technologies to the current rockets (which soon run out of fuel).
I don't know what lab you are working at, but I hope they are not designing anything I might travel in soon..... |
i get what you're saying, but your not getting me 
That is because much of what you have said is either wrong, meaningless or unexplained.
How do you accelerate a 'bubble' without accelerating the contents of the bubble? Surely both the bubble and the contents are in the same inertial frame of reference and will therefore be accelerated at the same rate?
In the future of 2020 or (I think) , everything may be possible ...
It will be hard if the technology is quite low.... 
| kristi01 wrote: |
Imagine traveling in a plane. How fast are you travelling? |
Anywhere from 90mph to 300mph, probably. Let's assume you're in a fast jet at 300mph.
| Quote: |
Now imagine travelling 10 times that speed. basically your body cant take the speed. you'd disintegrate into millions of pieces. its not a matter of traveling into the future and getting old. your body just cant be hurtling through space at the speed of light, with the expectation of coming out of it alive.
|
10 x 300: 3000mph
Now, would you 'disintegrate into millions of pieces' at 3000mph?
Aircraft speed record (SR-71 blackbird (kudos to the USAF)): 2194mph, still safe, supposedly.
So, let's consider the speed of the space shuttle during reentry: 17500mph... And yet the crew lives! (most of the time)
Really, I did laugh at the idea that going 10x the speed of a plane could cause disintegration...Interestingly enough this argument was first used to oppose the trains in Georgian/Victorian times. Various people, at the time, were absolutely convinced that the human body could not travel at speeds approaching 30mph. They were convinced that at such 'reckless' speeds one would be unable to breathe and would suffocate | Bikerman wrote: |
| Interestingly enough this argument was first used to oppose the trains in Georgian/Victorian times. Various people, at the time, were absolutely convinced that the human body could not travel at speeds approaching 30mph. They were convinced that at such 'reckless' speeds one would be unable to breathe and would suffocate |
Had they never ridden a horse 
Out of interest , did anyone of the time come up with a figure of the velocity needed to kill a human ?I'm not sure. It's difficult to know where the fear first originated. It is recorded that Queen Victoria would not let any train she took go more than 20mph. It is also recorded that a visiting royal (the Shah of Persia) insisted that his train stick to 15mph on the advice of his doctors who were frightened lest he suffocate.
Interestingly enough the railways (in early Victorian times) were also associated with 'railway spine' - a early form of whiplash. Doctors at the time were inundated with patients claiming symptoms which we would nowadays identify as severe whiplash. The is probably where the whole whiplash scam started.
I read a story somewhere about a pilot who ejected himself out of a jet plane travelling around the speed of sound without a helmet or protective gear. The effect of the air pushing against his exposed skin together with the increased effect of gravity caused his blood to spurt out of his blood vessels and his eyes to flutter so quickly that they bled violently. He survived, but only just.
I don't know what speed he was travelling at, but I'd think that anything greater than this could kill someone. Of course, the effects would be different on the ground travelling horizontally, but the effect itself could still be similar, if not so violent.
The idea of being fearful of travelling faster than 20mph may seem ludicrous to us, but imagine travelling at at the speeds modern trains travel at now, but without a carriage to protect you. Travelling at 60+mph in a open top car can cause terrible pain on your eyes and face. Imagine travelling faster than that. The Victorians may have been wrong believing that it could kill you, but it could still be terribly painful.
EDIT: I also found this article on accelerations that could kill. I cannot confirm the truthfulness of the science behind it, but its still an interesting read http://hypertextbook.com/facts/2004/YuriyRafailov.shtml You are confusing three issues - air resistance, speed and acceleration.
Speed doesn't hurt at all. We are currently travelling very fast indeed by some measures (compared to, for example, the sun). In fact 'speed' is a meaningless measure unless you say what you are measuring it against.
Velocity through air can certainly hurt. As a motorcyclist I have done 'the ton' on un-faired bikes and I can tell you it certainly pushes your head back. Bear in mind, though, that freefall for a parachutist is about 120mph and there are no significant health problems associated (providing the parachute works, of course).
Acceleration is another matter. The human body cannot stand prolonged high-g acceleration. Fighter pilots train for an exposure of between 6 and 12g for a few seconds. Most people will black-out at anything above about 6g for more than 5-10 seconds.
| Bikerman wrote: |
You are confusing three issues - air resistance, speed and acceleration.
Speed doesn't hurt at all. We are currently travelling very fast indeed by some measures (compared to, for example, the sun). In fact 'speed' is a meaningless measure unless you say what you are measuring it against.
Velocity through air can certainly hurt. As a motorcyclist I have done 'the ton' on un-faired bikes and I can tell you it certainly pushes your head back. Bear in mind, though, that freefall for a parachutist is about 120mph and there are no significant health problems associated (providing the parachute works, of course).
Acceleration is another matter. The human body cannot stand prolonged high-g acceleration. Fighter pilots train for an exposure of between 6 and 12g for a few seconds. Most people will black-out at anything above about 6g for more than 5-10 seconds. |
Nicely put comparison of the three. If i had one quibble it would be that in the sentence, "Velocity through air can certainly hurt." you have switched terms between speed and velocity - and while the difference doesn't really matter here, the switcheroo might cause confusion. i'd also add a comment to make it clear that the reason it hurts is the air resistance, not the speed, like this: "Speed through air can certainly hurt, because of the air resistance." Oh, and i might also add a note at the end of the second and third paragraphs about the extremes: the extreme case of air resistance is burning up (cf. Columbia) or being torn apart (can't think of an example, can you?), whereas the extreme case of acceleration is... smoosh. Helps make the differences even more clear. (i suppose you could also mention the extreme case of speed is time dilation... but that would be confusing the issue. ^_^)
But other than that, it's a rather succinctly put compare and contrast of the three. It would make a nice reference.Will time travel ever be possible? Yes
Could time travel possible ever be possible for complex molecular beings like human beings? I highly doubt it.
We could very likely send individual atoms or molecules back in time or into the future, but for a complex molecular beings like ourselves or animals - no.
I believe that it may be possible to time travel. it was said that it happened in the "Philadelphia Experiment" when there was a large amount of Electromagnetic Disturbance creating Einstein's "Unified Field Theory" the maps of space and time were folding making the ship tele-port from Philadelphia to Norfolk, it was also said that it went into the future and had alien encounter before returning to Philadelphia (when i assume the power for the Electromagnetics was shut off).
But this probably isnt a good idea because the molecules that traveled through the wormholes created by folding space and time jumbles the human electronic & magnetic signals creating unworldly phenomenons that always lead to death.
The LHC can possible cause time travel to become reality. However, everytime it is fixed, it breaks down again. Which could open another discussion: would God allow us to find the secret of life?
The piece below is taken from http://www.vnunet.com/vnunet/news/2209280/travel-possible-months
Russian scientists have claimed that time travel could take place this year as an inadvertent by-product of the Large Hadron Collider (LHC) run by Cern.
Mathematicians Irina Aref'eva and Igor Volovich said that when the LHC begins to smash atoms into each other the conditions will be perfect to open a wormhole into the distant future.
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"Proton-proton collisions at the LHC could lead to the formation of time machines (space-time regions with closed time-like curves) which violate causality," said the scientists in a research paper.
"One model for the time machine is a traversable wormhole. We argue that the traversable wormhole production cross section at the LHC is of the same order as the cross section for black hole production."
The other possibility, according to the mathematicians, is that miniature black holes will be formed under the French and Swiss countryside.
However, if the time machine hypothesis is correct we will not be seeing visitors from the future because the wormholes will be barely larger than atoms.
Proton-proton collisions at the LHC could lead to the formation of time machines which violate causality
The LHC is the world's largest scientific instrument, consisting of a 27km loop 100 metres under the French and Swiss countryside. It is due to go live later this year. If time travel is possible in the future, where are all the future people?
| PatTheGreat42 wrote: |
| If time travel is possible in the future, where are all the future people? |
Many of the theories on time travel only allow time travel to the point when the time machine was built. So there would be no time travelers because there is no time machine.Anyone who's interested in this subject should watch "Primer" It's an excellent movie about some engineer friends who are messing around in their garage trying to make a a compact high-temperature superconductor as a sort of science project. They accidentally create a time machine. It's very interesting and pretty realistic for a movie on this subject. One of my favorites.
I try not to think to much about these things but my old physics teacher used to believe we would have the answer once we broke the speed of light.
Idk.
| Noremac wrote: |
I try not to think to much about these things but my old physics teacher used to believe we would have the answer once we broke the speed of light.
Idk. |
If we could break the speed of light, that would be the answer. ^_^;
Any travel faster than light travels backwards in time. | Indi wrote: |
| Noremac wrote: | I try not to think to much about these things but my old physics teacher used to believe we would have the answer once we broke the speed of light.
Idk. |
If we could break the speed of light, that would be the answer. ^_^;
Any travel faster than light travels backwards in time. |
Theoretically, but there is no proof, you could just be traveling faster than light with no other result than moving from A - B in a faster way.
But saying that i agree with you, because when we break the sound barrier a sonic boom happens, so im thinking when we break the light barrier we would have a photon boom that bends the space-time continuum making us jump to a random place at a random time that we have no control over.
Eh, we will never know until we get there. | Parkour_Jarrod wrote: |
| Theoretically, but there is no proof, you could just be traveling faster than light with no other result than moving from A - B in a faster way. |
Err....you have heard of Einstein I presume? You do know about a little thing called Relativity (specifically Special Relativity) ?
Now, whilst it is true, technically, to say that we have no proof that superluminary speeds would result in travelling backwards in time, we can certainly say that time slows with relative velocity. That means we know for sure that travelling very fast most certainly does have an affect on time. Since Relativity has proven accurate everytime it is tested and since Relativity tells us that, at c, time is effectively stopped, then we presume, with very good reason, and theoretical support, that any superluminary velocity would result in travelling backwards through time. | Bikerman wrote: |
| Parkour_Jarrod wrote: | | Theoretically, but there is no proof, you could just be traveling faster than light with no other result than moving from A - B in a faster way. |
Err....you have heard of Einstein I presume? You do know about a little thing called Relativity (specifically Special Relativity) ?
Now, whilst it is true, technically, to say that we have no proof that superluminary speeds would result in travelling backwards in time, we can certainly say that time slows with relative velocity. That means we know for sure that travelling very fast most certainly does have an affect on time. Since Relativity has proven accurate everytime it is tested and since Relativity tells us that, at c, time is effectively stopped, then we presume, with very good reason, and theoretical support, that any superluminary velocity would result in travelling backwards through time. |
Yes i have heard of Einstein and Relativity, but, we don't fully understand the dimension of time, sure we can measure it and judge age and such but we do not know it's full fundamental qualities.
So in saying that we could assume that time is slowing down or we could presume that time isn't slowing down but rather the vibrations of atoms seem to be slowing down as we put more force on them making the second longer (because we all know that 1 second is 9,192,631,770 vibrations of an atom).
Therefore making our judgment of time make each second seem long the faster we travel.
Einstein also states that to reach the speed of light we would need a source of infinite energy to make such velocity so if we take that into account, the force placed on an atom at our current velocity to get the vibrations for a second compared to the force that is placed on an atom at the speed of light the force would be considerately different causing the atom's vibrations to slow down by an extreme number making our measurement of time to slow down thus making our mind to think that it is slowing down when it is staying at the same speed but our perception is slowing down.
but of course that argument is probably invalid by something that ive missed (my mind isn't completely on this post ATM doing school H/W)
Another thing because we don't understand all the fundamental rules of time we could in fact be an error by traveling through time. For example if we do crack the barrier and travel at super-luminary speeds we could stop time completely causing the universe to stop expanding but instead go back to its original state and compacting itself into a ball of super high density energy such as would be needed to get to such speeds. | Parkour_Jarrod wrote: |
| Yes i have heard of Einstein and Relativity, but, we don't fully understand the dimension of time, sure we can measure it and judge age and such but we do not know it's full fundamental qualities. |
True.
| Quote: |
| So in saying that we could assume that time is slowing down or we could presume that time isn't slowing down but rather the vibrations of atoms seem to be slowing down as we put more force on them making the second longer (because we all know that 1 second is 9,192,631,770 vibrations of an atom). |
No, that does not work. We KNOW that objects moving at a high relative velocity experience slower time than a stationary observer. This has been confirmed repeatedly and is used routinely in systems such as GPS. The idea of time dilation resulting from putting 'force' on atoms is flawed. SR operates when there is no acceleration (ie no external force acting on a body).
| Quote: |
| Another thing because we don't understand all the fundamental rules of time we could in fact be an error by traveling through time. For example if we do crack the barrier and travel at super-luminary speeds we could stop time completely causing the universe to stop expanding but instead go back to its original state and compacting itself into a ball of super high density energy such as would be needed to get to such speeds. |
Well, according to GR/SR there is no way to get to c for anything massive so this should not be a problem. I think you are confusing relative and absolutes here. An object travelling at high velocity has no effect on other objects - it is the relative frames of reference that are 'out of sync'. | Bikerman wrote: |
| Quote: | | Another thing because we don't understand all the fundamental rules of time we could in fact be an error by traveling through time. For example if we do crack the barrier and travel at super-luminary speeds we could stop time completely causing the universe to stop expanding but instead go back to its original state and compacting itself into a ball of super high density energy such as would be needed to get to such speeds. |
Well, according to GR/SR there is no way to get to c for anything massive so this should not be a problem. I think you are confusing relative and absolutes here. An object travelling at high velocity has no effect on other objects - it is the relative frames of reference that are 'out of sync'. |
True well as i did state before i wasn't think on the post 100% was multi tasking so i hope you can excuse me for such error. But i would also like to say that if we did travel at super-luminary speeds and time DID go backwards the time for the entire universe would have to go backwards not just for the object that is traveling at said speed or we wouldn't time-travel as the related discussion is said to say the events would stay how they are but we would escape the time period we are in as measured by our second.
P.S. you seem like a really interesting person, if you ever come to Brisbane Australia i would like to have a chat, you seem to be very knowledgeable and i think it would be rather interesting (not trying to flatter being serious). | Parkour_Jarrod wrote: |
| True well as i did state before i wasn't think on the post 100% was multi tasking so i hope you can excuse me for such error. But i would also like to say that if we did travel at super-luminary speeds and time DID go backwards the time for the entire universe would have to go backwards not just for the object that is traveling at said speed or we wouldn't time-travel as the related discussion is said to say the events would stay how they are but we would escape the time period we are in as measured by our second. |
Well, I can't see how time for the universe would change at all - if we imagine the object in an inertial frame of reference moving > c then the frame of the universe would remain constant...
| Quote: |
| P.S. you seem like a really interesting person, if you ever come to Brisbane Australia i would like to have a chat, you seem to be very knowledgeable and i think it would be rather interesting (not trying to flatter being serious). |
I've travelled in Australia a couple of times (drove from Darwin down to Adelaide, Melbourne, Sydney and Canberra. Never been to Brisbane though and unfortunately have no plans currently to travel over to Oz. If I do I'll let you know | PatTheGreat42 wrote: |
| If time travel is possible in the future, where are all the future people? |
Yeah, I also asked myself the same question.
But who knows? We might have met people from the future, we just didn't know, because they didn't tell us. It can also be possible that time travel has been invented in the future, and there could be laws restricting people from traveling through time as a hobby, LOL...
I just don't think that time travel will be invented in this (or my) lifetime. A group of German scientists in the 1900's broke the speed of light with an particle. Don't quite remember what it is. Sorry i dont have a link either. It was said that the particle was at the end before it began to leave the tunnel. So in theory "Time Travel" is impossible. It will just decrease the time it takes to get somewere.
| manlear wrote: |
| A group of German scientists in the 1900's broke the speed of light with an particle. Don't quite remember what it is. Sorry i dont have a link either. It was said that the particle was at the end before it began to leave the tunnel. So in theory "Time Travel" is impossible. It will just decrease the time it takes to get somewere. |
I don't believe this even for a second. If this were true it would be all over the place and easy to find.It is pretty easy to find. if i new their names it would be easier. They sent a particle through some kind of tube that had gas in it. The U.S. Navy did the same.
| manlear wrote: |
| It is pretty easy to find. if i new their names it would be easier. They sent a particle through some kind of tube that had gas in it. The U.S. Navy did the same. |
They can send a particle through a tube all they want it still won't go past the speed of light in a vacuum. Unless they magically had a source of infinite energy. Which they didn't. | Bikerman wrote: |
The fastest we can send information is c (speed of light). There are theoretical models which use Relativistic Frame Dragging to increase this (by moving the frame of reference as well as the information signal) but these normally rely on huge gravity sources (spinning black holes). A US physicist called Ron Mallett has proposed the same idea (frame dragging) but using high energy laser beams instead of gravity to 'drag' spacetime.
The physicists I know are very sceptical about the idea.
http://en.wikipedia.org/wiki/Ronald_Mallett
The other proposal for time travel that makes scientific sense, if not practical sense, involves wormholes. Assuming they exist, and can be formed at will, then the problem is that they would be inherently unstable and would require all sorts of exotic matter to keep open.
Most physicists think this is science fiction.
All the other proposals I have seen are pseudo-scientific claptrap - often based around misunderstandings of quantum physics (specifically quantum entanglement). |
For the man that was saying i was wrong. This man wrote it ^ not the german one though. The U.S. Physicist.^^This has nothing to do with the whole particle going faster than the speed of light thing. What is proposed by the wormhole idea is not actually going faster than the speed of light. It is akin to taking a shortcut.
Ohs... i made a fool of myself. I think the single most persuasive evidence that time travel isn't possible is the fact that nobody from the future has come to visit us yet.
| pscompanies wrote: |
| I think the single most persuasive evidence that time travel isn't possible is the fact that nobody from the future has come to visit us yet. |
This doesnt actually mean much as many of the theories on time travel state that you could only travel back as far as the point when the machine was built. No time travelers because there is no time machine. | manlear wrote: |
| It is pretty easy to find. if i new their names it would be easier. They sent a particle through some kind of tube that had gas in it. The U.S. Navy did the same. |
(Just to butt in here with a little correction....
manlear is right... sort of. ^_^
It has been widely reported that several groups of scientists have made photons move faster than light.
And they're right... sort of. ^_^;
The problem when talking about light is that a photon is a complex and counter-intuitive thing. There are actually several "speeds" of light, some of which are a lot faster that c. The particular speed of light you mean depends on the context, but is usually the group velocity. The experiments manlear is thinking of have gotten the group velocity to be two or three hundred times c.
But - and i know this sounds odd - nothing about physics has changed. The speed of light is still a universal constant that no matter, energy or signal can exceed. Even though we can make the group velocity of a photon 200+ times c, we cannot use this photon to send information any faster than c.
To put it in simple terms, in those experiments where scientists seemed to exceed c, they cheated. What they sorta-kinda did is stretch a photon out, and then measure different parts of it. Imagine you said that cars cannot travel faster than 100 km/h, and i set up an experiment to prove they can by doing this: i get a covered road 100 km long... and a car that is 99 km long... and i put the back end of the car at the start line... then start the clock and drive the car at a normal speed... and a couple minutes later you see the front of the car at the finish line. On the one hand, i did get the car from the starting line to the finish line much faster than a normal car travelling at 100 km/h. But on the other, i never actually exceeded c. If you actually wanted a package delivered and you put it in the trunk at the start of the test, even though the front of the car gets to the finish line in just a few minutes, the package (in the trunk) won't get there for an hour at least.
So, yes, some things (several things actually) do travel faster than c. But no matter, energy or information can travel faster than c.) | yagnyavalkya wrote: |
I read a book with the following review of it
In this fascinating book, the renowned astrophysicist J. Richard Gott leads time travel out of the world of H. G. Wells and into the realm of scientific possibility. Building on theories posited by Einstein and advanced.
What do you guys think is it possible to travel in time |
If it were, how is it that someone from the future has not come back in time and prevented humanity from committing its worst excesses, like the two world wars, Darfur and hundreds of other atrocities.
There could be an entropic law which prevents you from changing anything. But I seriously doubt it.
Because if somehting changed. You in the now would not notice anything amiss.
It may be possible in certain universes for it to occur where the laws of physics are different.
But the problem as always is how do you know that someone has traveled or effected a change. How can you be sure that the change you effect (as a travellere from the future) doesn't wipe out your existence in your future. | chiragpatnaik wrote: |
| yagnyavalkya wrote: | I read a book with the following review of it
In this fascinating book, the renowned astrophysicist J. Richard Gott leads time travel out of the world of H. G. Wells and into the realm of scientific possibility. Building on theories posited by Einstein and advanced.
What do you guys think is it possible to travel in time |
If it were, how is it that someone from the future has not come back in time and prevented humanity from committing its worst excesses, like the two world wars, Darfur and hundreds of other atrocities.
There could be an entropic law which prevents you from changing anything. But I seriously doubt it.
Because if somehting changed. You in the now would not notice anything amiss.
It may be possible in certain universes for it to occur where the laws of physics are different.
But the problem as always is how do you know that someone has traveled or effected a change. How can you be sure that the change you effect (as a travellere from the future) doesn't wipe out your existence in your future. |
Thats why as it was stated earlier that when a time machine is built (if it is) it will only allow you to go back as far as when it was created but as far forward as you want etc etc. | Parkour_Jarrod wrote: |
| chiragpatnaik wrote: | | yagnyavalkya wrote: | I read a book with the following review of it
In this fascinating book, the renowned astrophysicist J. Richard Gott leads time travel out of the world of H. G. Wells and into the realm of scientific possibility. Building on theories posited by Einstein and advanced.
What do you guys think is it possible to travel in time |
If it were, how is it that someone from the future has not come back in time and prevented humanity from committing its worst excesses, like the two world wars, Darfur and hundreds of other atrocities.
There could be an entropic law which prevents you from changing anything. But I seriously doubt it.
Because if somehting changed. You in the now would not notice anything amiss.
It may be possible in certain universes for it to occur where the laws of physics are different.
But the problem as always is how do you know that someone has traveled or effected a change. How can you be sure that the change you effect (as a travellere from the future) doesn't wipe out your existence in your future. |
Thats why as it was stated earlier that when a time machine is built (if it is) it will only allow you to go back as far as when it was created but as far forward as you want etc etc. |
That's clever, but intellectually lazy. Who stops you from going back in time? society? the machine itself? how does the machine no when was it created?
As far as going into the future is concerned. You could affect things in the future as well. You could date your great great grand daughter. While there would be no paradox in this particular case, but social consequences of the same are huge.
Not simple my dear friend. | chiragpatnaik wrote: |
| Parkour_Jarrod wrote: | | chiragpatnaik wrote: | | yagnyavalkya wrote: | I read a book with the following review of it
In this fascinating book, the renowned astrophysicist J. Richard Gott leads time travel out of the world of H. G. Wells and into the realm of scientific possibility. Building on theories posited by Einstein and advanced.
What do you guys think is it possible to travel in time |
If it were, how is it that someone from the future has not come back in time and prevented humanity from committing its worst excesses, like the two world wars, Darfur and hundreds of other atrocities.
There could be an entropic law which prevents you from changing anything. But I seriously doubt it.
Because if somehting changed. You in the now would not notice anything amiss.
It may be possible in certain universes for it to occur where the laws of physics are different.
But the problem as always is how do you know that someone has traveled or effected a change. How can you be sure that the change you effect (as a travellere from the future) doesn't wipe out your existence in your future. |
Thats why as it was stated earlier that when a time machine is built (if it is) it will only allow you to go back as far as when it was created but as far forward as you want etc etc. |
That's clever, but intellectually lazy. Who stops you from going back in time? society? the machine itself? how does the machine no when was it created?
As far as going into the future is concerned. You could affect things in the future as well. You could date your great great grand daughter. While there would be no paradox in this particular case, but social consequences of the same are huge.
Not simple my dear friend. |
Of course there are complications sure we can't go back in time past when it was made because of the laws of space time, but Once you can go forward You can go back and forward as much as you want, the only problem is that humans would abuse it, we can't know but we can speculate...I personnaly don't know i'd say no not really though if We did it would be impractical because time is best left alone. though it would be cool. teleportation on the other hand...we'll probly have that down in 50 years perfected in a hundred.
Maybe in a few hundred years 
| Roflcopter wrote: |
| Maybe in a few hundred years |
or next year... who can tell. Serendipity is very much the order of the day in basic scientific research.according to modern day experts, it will never be possible....
but i like to think that anything is possible... its fun to dream
"i have a dream" said martin luther king, and it is very appropriate for time travel 
| Jaan wrote: |
according to modern day experts, it will never be possible....
but i like to think that anything is possible... its fun to dream
"i have a dream" said martin luther king, and it is very appropriate for time travel |
earth was the center of the universe some 500 hundred years ago. Vaccination was not even looked offer. Flight was impossible 150 years ago. Space was unthinkable. Even by modern scientists.
So like I said. Serendipity.I hope it won’t be possible… I don’t want to know future, I want to live, follow my dreams and see where I will end up.
Who knows what would happen if I see myself in future… Maybe I would try hard to change something and... Maybe I would create a new future… Confusing.
Just enjoy the present.
| biljap wrote: |
I hope it won’t be possible… I don’t want to know future, I want to live, follow my dreams and see where I will end up.
Who knows what would happen if I see myself in future… Maybe I would try hard to change something and... Maybe I would create a new future… Confusing.
Just enjoy the present. |
From the NYT...
http://www.nytimes.com/2009/10/13/science/space/13lhc.html?pagewanted=2&_r=1
A pair of otherwise distinguished physicists have suggested that the hypothesized Higgs boson, which physicists hope to produce with the collider, might be so abhorrent to nature that its creation would ripple backward through time and stop the collider before it could make one, like a time traveler who goes back in time to kill his grandfather.
Also...
“For those of us who believe in physics,” Einstein once wrote to a friend, “this separation between past, present and future is only an illusion.”... And they call themselves physicists?
| catscratches wrote: |
| ... And they call themselves physicists? |
rewind 500 odd years and the church was demonising Galileo...As I am interested in the subject, I followed the discussion in this thread, I hoped to express my opinion at the first moment but after reading some posts, decided to just take some quotes that entertained me, got my attention, or even made me laugh loudly
P.S. : All respect to every FriHost member .. no offense .. all I mean is to make everyone enjoy reading the thread.
| DoctorBeaver wrote: |
| What if time travel technology was developed by Microsoft? "You have just crashed into Napoleon. Please re-boot for this change to take effect" |
Go to that post
| SlideR.nl wrote: |
| takashiro wrote: | | I don't think it possible since no one living in the future is able to come back to visit us. |
Maybe they are visiting us but you can't see them. It's just an option |
Go to that post
| Bikerman wrote: |
| Various people, at the time, were absolutely convinced that the human body could not travel at speeds approaching 30mph. They were convinced that at such 'reckless' speeds one would be unable to breathe and would suffocate |
Go to that post
| Bikerman wrote: |
| freefall for a parachutist is about 120mph and there are no significant health problems associated (providing the parachute works, of course). |
Go to that post
| joomla wrote: |
The piece below is taken from http://www.vnunet.com/vnunet/news/2209280/travel-possible-months
.......
Mathematicians Irina Aref'eva and Igor Volovich said that when the LHC begins to smash atoms into each other the conditions will be perfect to open a wormhole into the distant future.
Advertisement
Click here to find out more!
...... |
Go to that post
| keane wrote: |
| We might have met people from the future, we just didn't know, because they didn't tell us. |
Go to that post
| WHwarsInc wrote: |
| time is best left alone |
Go to that post
| chiragpatnaik wrote: |
| A pair of otherwise distinguished physicists have suggested that the hypothesized Higgs boson, which physicists hope to produce with the collider, might be so abhorrent to nature that its creation would ripple backward through time and stop the collider before it could make one, like a time traveler who goes back in time to kill his grandfather. |
Go to that post
and as a reply to the above | catscratches wrote: |
| ... And they call themselves physicists? |
Go to that post
Hope that everyone read this enjoyed it I hope it would be possible, because it will prove that our technology will become stronger and stronger
to overcome different kinds of traditional problem e.g. ( how traveling speed can be faster than light speed? ).
I think, it's not possible to travel backwards,because noone have seen any objects from future (It's a weird quessing ). But I think, you can travel foward in time.
Sorry for my English! 
Time travel may be possible, but it will never probably be available to everyone. If it is, I'm sure that some nut would've come today from the future. But since we never got to see any of those from the future, I think we won't be seeing the technology ever.
That is, of course, if we think of time travel as how the movies tell us.
And don't you think it would be lame if we invent the ability to go to the future?
I mean, if it is possible, then only one future would await us.
Hope so, hope its free to 
| kristi01 wrote: |
| Bikerman wrote: | | kristi01 wrote: | | I work at a lab, and my theory is that we should be able to accelerate outside an object while simultaneously de-accelerating within it. (so we dont turn to mush) |
That makes no sense to me - you will have to explain further.. |
Imagine traveling in a plane. How fast are you travelling?
Now imagine travelling 10 times that speed. basically your body cant take the speed. you'd disintegrate into millions of pieces. its not a matter of traveling into the future and getting old. your body just cant be hurtling through space at the speed of light, with the expectation of coming out of it alive.
Now. if you were trapped in a bubble that was unaffected to the speed, in other words- inside the bubble you were not accelerating. but on the outside the bubble was accelerating (at the speed of light) |
No, I think you have a few misconceptions. Take the plane, for example. A typical speed might be 500mph. The shuttle travels at about 24,000 mph. No problem.
The problem is acceleration (ie getting up to cruising speed). The human body can't cope with much more than 2-3g over a sustained period. That need not be a problem, however, since a constant 2g acceleration will soon have you travelling at fantastic speeds.
You cannot 'accelerate at the speed of light' - acceleration is the rate of change of velocity.
The other problem, of course, is relativity. That means you can never actually get to c (speed of light). That itself need not be a problem because as you get close then time-dilation kicks in and you can cover fantastic distances in a relatively short time (subjective time).
The major problem, therefore, is sustaining acceleration for long periods of time - that is why we need different technologies to the current rockets (which soon run out of fuel).
I don't know what lab you are working at, but I hope they are not designing anything I might travel in soon lolI don't think we'll ever be able to time travel and I also don't think that time travel is a good idea. It can hurt everything.
I'm no scientist, but I do honestly believe that travelling back in time is just not possible. Travelling forward in time however, I think is possible.
| welshsteve wrote: |
| I'm no scientist, but I do honestly believe that travelling back in time is just not possible. Travelling forward in time however, I think is possible. |
When thinking about this for some reason this sounds more plausible than backwards.
