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 F้d้rale 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.
