What if you can reverse time with general relativity?

[IAstroViz]

General relativity states that, time ticks slower when you get closer to a gravitational point in space. But can time actually reverse? I mean it's not impossible.

[Greg H.]

From what I remember GR does not specifically preclude the idea of time running backwards - that is to say, the equations will resolve regardless of the sign on the time variables.

 

Getting time to actually run backwards is another matter entirely though.

[Mordred]

although faster than light (tachyonic particles) have been proposed as time reversal. No evidence has ever been found.

 

There exists a primary dilemma. Cause before effect. Law of causality.

 

You can find numerous literature of ftl particles and time reversal correlations. However they are in the realm of mathematical proposals without observable evidence. Much like multiverse proposals.

From what I remember GR does not specifically preclude the idea of time running backwards - that is to say, the equations will resolve regardless of the sign on the time variables.

 

Getting time to actually run backwards is another matter entirely though.

Correct I recall a study a few years ago on this they based everything being FTL, but ran into a problem at the speed c being the same as when a particle reaches c from subliminal in singularity conditions.

Not sure I'll be able to find that study as it was late 90 ish. If I recall correct was done in Australia

Edited May 2, 2015 by Mordred

[ajb]

Most of physics is time reversal symmetric, so for the most part there seems no reason why time could not run backwards. This is the problem of the 'arrow of time'. There are several arrows here, some of which are restatements of the second law of thermodynamics.

 

This should not be confused with the idea a closed time-like curves. The clock as carried by our time traveller still runs forwards.