Do closed timelike curves exist? And, if so, would they allow us to travel back in time?

This question comes from http://en.wikipedia.org/wiki/Closed_timelike_curve. If they exist, would CTCs conflict with Einstein's special theory of relativity or general relativity?

mathematician2006-03-09T10:36:35Z

Favorite Answer

There are some theoretical models based of GR that allow closed time-like curves. Most working physicists think those models are bunk. To have such curves requires a curves space-time, so is the domain of GR, not SR.

To see why such a curve would allow time travel, you have to understand what the terms mean. Time-like means that at any point on the curve, the tangent vector is into the future. In other words, someone going along that space-time curve would always be going 'forward in time' in *their* mind. Closed, in this context, means that the curve comes back to the starting point, again *in space-time*. So the traveller would always be going forward in time in *their* mind, but would end up back at the same point in space and time as when they started. Looks like time travel to me. ;)

Snaglefritz2006-03-09T10:31:57Z

When I was living in the year 2136 A.D. people were still asking this question and it has not been proved to exist. Most things about Time are Theories, Unproven assumptions. In Theory the curves could exist. This gives more Theory of Dimensions and etc. There are many books on the Subject of Time Travel and how it would work as far as not changing History and things like that. It does make for interesting reading and excites the imagination. Search Amazon.com for a good book on Time Travel and read it, and do not forget your Public Library, books are Free there. I think you would enjoy learning the many Fascinating Theories people have.

position282006-03-09T10:23:37Z

Well who's referance of time.
Just kidding theres no such thing as time travel.
Well you can travel forward in time at one seccond per seccond.
It's and interesting subject to read about its just good insperation for reading lots of scientific stuff.
There is nothing to disprove it absolutely so you just end up reading and reading.
There are probably good curved power sources.
Check this out is light effected by gravity?
If so shouldnt there be a band of light somewere far away orbiting our sollar system.
How much power would it have.
Would it be a good source of energy for an attempt on einsteins time.
Danit now I gotta comb my hair thinking like that gives me einstein hair. Then my co workers call me don king.

Ummm no time travel is not possable.
Although the more you know about it the more it seems possable.
Most of my frends think time travel is possable.

Anonymous2006-03-09T10:25:13Z

The only true time travel can only happen in a person's mind, through progressive relaxation techniques.