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Questions tagged [closed-timelike-curve]

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Do any quantum gravity theories deal with closed timelike curves?

As far as I'm aware, there are no quantum gravity theories that deal directly with closed timelike curves. Some of them (like canonical quantum gravity, causal dynamical triangulation and loop quantum ...
4
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0answers
135 views

Role of the observer in Gödel's universe

I am here to clarify myself about the role of the observer in Gödel's solution (1949) of Einstein's field equations. The Universe we are dealing with is anisotropic, since the axis of rotation ...
2
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0answers
56 views

Is there any well-known holographic duality that allows wormholes and CTCs to exist?

Is there any well-known holographic duality (like AdS/CFT or holographic principle in string theory/black holes) that contains wormholes and Closed Timelike Curves? I was discussing this with a ...
2
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0answers
45 views

Brouwer fixed point theorem

How does the Brouwer fixed point theorem (which provides a solution to the photo camera paradox of a causal loop) generalise to show that objects in closed time-like curves do not violate the second ...
2
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0answers
248 views

Physical reality of inner event horizon and inner ergosurface in a rotating black hole in D. Wiltshire et al. “The Kerr spacetime”

In chapter 1/The Kerr spacetime-a brief introduction by Matt Visser of D. Wiltshire, M. Visser, S.M. Scott "The Kerr spacetime - Rotating black holes in general relativity" the author presents a ...
2
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0answers
122 views

Does our universe admit of a global time function?

My understanding of a global time function is this: a function whose value always increases as a body moves into its local future. My confusion is this: I gather that the Gödel Universe is bizarre ...
2
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0answers
92 views

Chronology protection for non-geodesic CTCs and imprisoned curves

As far as I can make out, the quantum part of the Chronology Protection Conjecture hinges on the fact that in curved space, in the semiclassical approximation, the stress energy tensor contains a term ...
1
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0answers
69 views

Would CTCs in wormholes change physical laws?

A wormhole is a speculative structure linking disparate points in spacetime, and is based on a special solution of the Einstein field equations solved using a Jacobian matrix and determinant. (https:...
1
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0answers
93 views

Causally benign spacetimes and the Minkowski torus

A notion encountered in field theory on non-globally hyperbolic manifolds is the notion of a spacetime being causally benign with respect to some field $\phi$, which is defined thusly : A ...
1
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0answers
58 views

Accelerating thin shell wormholes and closed timelike curves

The classical example of the conversion of a wormhole into a time machine is to consider two wormholes, one stationary and another one accelerating for some period before going back to its original ...
1
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0answers
105 views

Experimental test for a universal scale closed timelike curve?

So recently, in chat, I was interested in about what if our universe contains only one CTC (thus making it unlike the Gödel metric, van Stockum dust where there can be more than one CTCs found) and ...
0
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0answers
32 views

Would the space needed for a wormhole time machine prevent backwards time travel?

Let's say that there was a wormhole time machine where one would emerge from the distal end earlier than one entered the proximal end. Would the spacial separation required between the two mouths ...
0
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0answers
69 views

Misner space - closed timelike curves

Could someone give me a good resource to read about closed timelike curves in Misner space? Somewhere where they are actually derived and some comments are made for the simple 2D Misner space?
0
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1answer
75 views

Closed Trajectories in wormhole

This might seem trivial but if I want to go about finding closed trajectories in a wormhole with a metric: $$ds^2=-dt^2+dr^2+(b^2+r^2)(d\theta^2+sin^2\theta d\phi^2)$$ how should I approach that? Is ...