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The Cosmological Constant [PDF]
Living Reviews in Relativity, 2001 This is a review of the physics and cosmology of the cosmological constant. Focusing on recent developments, I present a pedagogical overview of cosmology in the presence of a cosmological constant, observational constraints on its magnitude, and the ...
Carroll Sean M.
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The cosmological constant in supergravity [PDF]
European Physical Journal C: Particles and Fields, 2018 We propose a supersymmetrisation of the cosmological constant in ordinary $$N=1$$ N=1 supergravity that breaks supersymmetry spontaneously by a constant Fayet-Iliopoulos (FI) term associated to a U(1) symmetry.
I. Antoniadis +3 more
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MeV Dark Energy Emission from a De Sitter Universe
Universe, 2023 The evolution of a de Sitter Universe is the basis for both the accelerated Universe and the late-stationary Universe. So, how do we differentiate between both universes?
Yasmín B. Alcántara-Pérez +3 more
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Black branes with cosmological constant
Journal of High Energy Physics, 2022 We study neutral black branes with flat and curved worldvolumes in the presence of a negative cosmological constant. We reduce the equations governing the dynamics of such objects to one second-order ODE and perform various asymptotic expansions of the ...
Rhucha Deshpande, Oleg Lunin
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Vacuum energy with mass generation and Higgs bosons
Physics Letters B, 2020 We discuss the Higgs mass and cosmological constant hierarchy puzzles with emphasis on the interplay of Poincaré invariance, mass generation and renormalization group invariance.
Steven D. Bass, Janina Krzysiak
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The Astrophysical Journal Letters, 2023 The light from an extragalactic source at a distance d will arrive at detectors separated by 100 au at times that differ by as much as 120( d /100 Mpc) ^−1 nanoseconds because of the curvature of the wave front. At gigahertz frequencies, the arrival time
Kyle Boone, Matthew McQuinn
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Dark matter from torsion in Friedmann cosmology
European Physical Journal C: Particles and Fields, 2022 A cosmological model in an Einstein–Cartan framework endowed with torsion is studied. For a torsion function assumed to be proportional to Hubble expansion function, namely $$\phi =-\alpha H$$ ϕ = - α H , the contribution of torsion function as a dark ...
S. H. Pereira +3 more
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Loop quantum gravity and cosmological constant
Physics Letters B, 2021 A one-parameter regularization freedom of the Hamiltonian constraint for loop quantum gravity is analyzed. The corresponding spatially flat, homogenous and isotropic model includes the two well-known models of loop quantum cosmology as special cases. The
Xiangdong Zhang, Gaoping Long, Yongge Ma
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Cosmological constant: Relaxation vs multiverse
Physics Letters B, 2019 We consider a scalar field with a bottom-less potential, such as g3ϕ, finding that cosmologies unavoidably end up with a crunch, late enough to be compatible with observations if g≲1.2H02/3MPl1/3. If rebounces avoid singularities, the multiverse acquires
Alessandro Strumia, Daniele Teresi
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On the cosmological constant problem
Physics Letters B, 2019 An additional variation of the Einstein-Hilbert action with respect to the Planck mass provides a constraint on the average Ricci scalar that prevents vacuum energy from gravitating. Consideration of the evolution of the inhomogeneous matter distribution
Lucas Lombriser
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