# Questions tagged [cosmic-string]

Questions about properties, dynamics and phenomenology of cosmic strings and superstrings.

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### Is the spinning Cosmic String spacetime totally vicious?

The spacetime $(M,g)$ is given locally at each point by the metric: $$g= -(dt + a \, d \phi)^2 + d\rho^2 + \kappa^2 \rho^2 \, d\phi^2 + dz^2 \ \text{where} \ \ a > 0$$ This is the spacetime of a ...
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### What is the manifold topology of a spinning Cosmic String?

Given the following metric which is that of a rotating Cosmic String: $$g=-c^2 dt^2 + d\rho^2 + (\kappa^2 \rho^2 - a^2) d\phi^2 - 2ac d \phi dt + dz^2.$$ can one determine the manifold topology ...
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### The Lebesgue covering dimension of the Cosmic String interval topology

Take the spacetime $(M,g)$ that satisfies Einstein's Field Equations exactly where $g$ is locally: $$g= - c^2 dt^2 + d \rho^2 + (\kappa^2 \rho^2 - a^2) d \phi^2 - 2 ac d\phi dt + dz^2 \$$ in the ...
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### Metric of a rotating Cosmic String

I searched on the internet superficially but I couldn't find it. Is there any reference that find the solution to Einstein's Field Equations for a rotating Cosmic String? Personally haven't got the ...
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### Cosmic string in real space

I am considering $U(1)$ global cosmic string. In the case of wine-bottle potential with real field ($\phi$), it is known that there exists a static solution that corresponds to cosmic string (or ...
19 views

### Analytic formulae for the gravitational field of a cosmic string/domain wall?

Is there any analytical approximate (newtonian, postnewtonian) formulae for the gravitational field/potential of cosmic strings/domain walls?
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### Cosmic Strings as Topological Defects (heuristics)

I have a lot of troubles to understand heuristically the principle behind Kibble's model for genesis of cosmic strings via Kibble mechanism. More precisely I not understand how to interpret following ...
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### Could inhomogeneties and/or topological defects break the fundamental symmetries of the universe?

I have heard that some types of inhomogeneties and topological defects (like cosmic strings) in cosmology have been proposed to be able to break fundamental symmetries of nature such as the Poincaré, ...
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### Can a cosmic string pass through the earth undetected?

The metric around a straight, static and infinitely long cosmic string is flat except for the topological deficit in the angular coordinate, as described for example here. As a result, there is no ...
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### Could Gott's Cosmic String Time Machine hypothetically be used as a poor man's Alcubierre drive?

I have read much speculation about Gott's theoretical use of cosmic strings for time travel, but if the colliding cosmic strings accelerated the spacecraft faster than light, as Gott theorizes, could ...
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### Energy density of a cosmic string in the Abelian Higgs Model (Nielsen-Olesen Vortex)

my question is what the energy density of a cosmic string in the abelian higgs model is? I have different sources (Scholarpedia Cosmic Strings, the book "Cosmic Strings and Topological Defects&...
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### Tension of a String

does anybody know a general relation between the tension of a string and it's energy density? I am at the moment learning about topological cosmic strings and calculated the energy density, now I do ...
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### Why is general relativity in (2+1) dimensions different from cylindrical systems in (3+1) dimensional GR?

The gravitational potential $\Phi$ of an infinite rod in newtonian gravity is $\Phi \sim \ln(r)$. This is the same as the gravitational potential of a point charge in two-dimensional Newtonian gravity ...
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### How does a Cosmic String accelerate a Black Hole?

I've read that a Cosmic String could accelerate a Black Hole, but I'm not exactly sure how that works. Is the Black Hole pulled along the length of the String? I've also heard it could accelerate ...
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### Cosmic string gravity assist?

Could a spacecraft hypothetically use the gravity of a cosmic string to carry itself along the length of the string?
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### Circling a Cosmic string in less than 360 degrees for faster space travel?

I've red that Cosmic strings would warp space such that one could circle a cosmic string in less than 360 degrees. How few degrees? If a ship were to circle a cosmic string in a spiral pattern, saving ...
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### Cosmic strings, domain walls, and magnetic monopoles are topological defects, but what's defecting?

Wikipedia gives an explanation of cosmic strings that I'm sure would be very helpful if I had a major in topology, but alas I do not. I know that a topological defect is any sort of discontinuity in a ...
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### Spacetime with a point defect

What is the metric for a spacetime with a point defect? Spacetime metric with line defects are well-known, they are basically Cosmic strings. Is anyone aware of an example for spacetime with point ...
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### Global cosmic strings evolution

Recently I've read about axion string. It can be shown that the energy per unit length of the string located along $z$ axis is $$\mu = 2 \pi f_{a}^{2}\ln\left( \frac{L}{\delta}\right),$$ where $L$ ...
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1 vote