Results 1 to 10 of about 375 (91)
A Portalino to the Twin Sector
Journal of High Energy Physics, 2023 Extensions of the Standard Model are often highly constrained by cosmology. New states in the theory can dramatically alter observed properties of the universe by the presence of additional matter or entropy.
Di Liu, Neal Weiner
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Dark photon dark matter from cosmic strings and gravitational wave background
Journal of High Energy Physics, 2023 Dark photon dark matter may be produced by the cosmic strings in association with the dark U(1) gauge symmetry breaking. We perform three-dimensional lattice simulations of the Abelian-Higgs model and follow the evolution of cosmic strings. In particular,
Naoya Kitajima, Kazunori Nakayama
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Axion dark matter with thermal friction
Journal of High Energy Physics, 2023 Cosmological evolution of axion field in the early universe might be significantly affected by a thermal friction induced by the axion coupling to thermalized hidden sector.
Kiwoon Choi +3 more
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Cosmological constraints on dark scalar
Journal of High Energy Physics, 2022 We discuss cosmological constraints on a dark scalar particle mixing with the Standard Model Higgs boson. We pay particular attention to the dark scalar production process when the reheating temperature of the Universe is very low, which allows us to ...
Masahiro Ibe +3 more
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Multifield positivity bounds for inflation
Journal of High Energy Physics, 2023 Positivity bounds represent nontrivial limitations on effective field theories (EFTs) if those EFTs are to be completed into a Lorentz-invariant, causal, local, and unitary framework.
Marat Freytsis +3 more
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The hand-made tail: non-perturbative tails from multifield inflation
Journal of High Energy Physics, 2022 It is becoming increasingly clear that large but rare fluctuations of the primordial curvature field, controlled by the tail of its probability distribution, could have dramatic effects on the current structure of the universe — e.g. via primordial black-
Ana Achúcarro +3 more
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A novel solution to the gravitino problem
Journal of High Energy Physics, 2023 In a general phenomenological model with local supersymmetry, the amount of massive gravitinos produced in early universe tends to violate the known dark matter density bound by many orders of magnitude.
Yu-Cheng Qiu, S.-H. Henry Tye
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Journal of High Energy Physics, 2022 We investigate both the null energy condition (NEC) violating scenario and the c T -diminishing scenario for generating enhanced power spectrum of primordial gravitational waves (GWs) during inflation, where c T is the propagating speed of primordial GWs.
Yong Cai, Yun-Song Piao
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Bouncing cosmology in modified gravity with higher-order curvature terms
Journal of High Energy Physics, 2023 A bouncing scenario of a flat homogeneous and isotropic universe is explored by using the reconstruction technique for the power-law parametrization of the Hubble parameter in a modified gravity theory with higher-order curvature and trace of the energy ...
J. K. Singh +3 more
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Moduli inflation from modular flavor symmetries
Journal of High Energy Physics, 2023 We study slow-roll inflation model controlled by the modular flavor symmetry. In the model, the modulus field plays a role of inflaton and the introduction of the stabilizer field coupled to a modular form in the superpotential produces the inflaton ...
Yoshihiko Abe +4 more
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