Questions tagged [cosmic-string]
The cosmic-string tag has no usage guidance.
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questions
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What's the connection between cosmic strings and the strings hypothesized in string theory?
I read somewhere that Edward Witten, the (once) big hotshot of string theory, said that the discovery of cosmic strings (at the beginning of this Wikipedia article it is written: "Not to be confused ...
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1answer
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What is a String Wall?
This question has nothing to do with sound waves, physical strings or walls...
I am reading: https://arxiv.org/abs/1709.07091
It states
"In the post-inflationary PQ symmetry breaking scenario, ...
0
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1answer
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I've read a cosmic string can accelerate a mass. Can someone explain how it works?
In the book Brief Answers to the Big Questions: the final book from Stephen Hawking Hawking describes cosmic strings as follows;
They are like rubber bands as they are under great tension, ...
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Candidates for cosmic strings
What are the observed candidates for cosmic strings (or other defects), that are not ruled out? With references if possible.
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Black hole and the cosmic string
For a regular black hole, the mass and energy of the black hole are identical（according to first law of black hole thermodynamics), but for a black hole with a cosmic string this is not satisfied. ...
3
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0answers
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Basic question on Cosmic Strings
What is the typical size of Cosmic String Loops?
If a loop is formed today, what are the restrictions on its size?
I would like to know if there is a distribution of cosmic strings depending on its ...
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votes
1answer
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Gravitational lensing and cosmic strings
Say we have a straight cosmic string lying along the $z$-axis, with energy-momentum tensor
$$T_{\mu\nu}=\mu\delta(x)\delta(y)\operatorname{diag}(1,0,0,-1)\tag{1}\label{1}$$
for some small positive ...
2
votes
1answer
141 views
Kalb-Ramond action and topological string radiation
Let's have simple scalar $\Phi$ action involves spontaneously symmetry breaking in a form
$$
\tag 1 S = \int d^{4}x\left( |\partial_{\mu}\psi|^{2} + \psi^{2}|\partial_{\mu}\theta |^{2} - \frac{\lambda}...
1
vote
1answer
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Global cosmic strings evolution
Recently I've read about axion string. It can be shown that the energy per unit length of the string located along $z$ axis is
$$
\mu = 2 \pi f_{a}^{2}\ln\left( \frac{L}{\delta}\right),
$$
where $L$ ...
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2answers
168 views
Cosmic string & grandfather paradox
Cosmic string was proposed several decades ago and there are claims stating it can span across the length of the universe and is less than an atom thick. How does a broken pieces of these cosmic ...
