Question

What are COSMIC STRINGS?

Answer 1

The cosmic Strings are the Hypothetical 1 dimensional topological defects which may have formed during a symmetry breaking phase transition in the early universe when the topology of the vaccum manifold Associated to this symmetry breaking was not simply

Answer 2

Cosmic strings is another such concept of Time Travelling. In short they can be defined as "narrow tubes of energy ranging the entire universe". It is predicted that they warp the space time fabric around them & thus forming an infinite loop. Some books claim that they've infinite mass, that's why they curve the fabric so much in such a particular configuration to make time travel possible.
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