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تسجيل مستخدم جديدInflation and cosmic (super)strings: implications of their intimate relation revisited
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Mairi Sakellariadou
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We briefly discuss constraints on supersymmetric hybrid inflation models and examine the consistency of brane inflation models. We then address the implications for inflationary scenarios resulting from the strong constraints on the cosmic (super)string tension imposed from the most recent cosmic microwave background temperature anisotropies data.
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Cosmic strings are predicted by many field-theory models, and may have been formed at a symmetry-breaking transition early in the history of the universe, such as that associated with grand unification. They could have important cosmological effects.
Scenarios suggested by fundamental string theory or M-theory, in particular the popular idea of brane inflation, also strongly suggest the appearance of similar structures. Here we review the reasons for postulating the existence of cosmic strings or superstrings, the various possible ways in which they might be detected observationally, and the special features that might discriminate between ordinary cosmic strings and superstrings.
The NANOGrav collaboration has recently presented its pulsar timing array data which seem compatible with the presence of a stochastic gravity wave background emitted by cosmic strings with a dimensionless string tension $Gmusimeq 2times 10^{-11}-3ti
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