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Unimodular Approaches to the Cosmological Constant Problem
Universe, 2023 We review selected aspects of unimodular gravity and we discuss its viability as a solution of the old cosmological constant problem. In unimodular gravity, the cosmological constant is promoted to a global degree of freedom.
Pavel Jiroušek
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Universe, 2020 The stage of a super-early (primordial) scale-invariant Universe is considered on the basis of the Poincaré–Weyl gauge theory of gravity in a Cartan–Weyl space-time. An approximate solution has been found that demonstrates an inflationary behavior of the
Ol’ga Babourova, Boris Frolov
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Modified Gravity Approaches to the Cosmological Constant Problem [PDF]
Universe, 2023 The cosmological constant and its phenomenology remain among the greatest puzzles in theoretical physics. We review how modifications of Einstein’s general relativity could alleviate the different problems associated with it that result from the ...
Foundational Aspects of Dark Energy (FADE) Collaboration +7 more
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On the cosmological constant problem [PDF]
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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Revisiting the Cosmological Constant Problem within Quantum Cosmology [PDF]
Universe, 2020 A new perspective on the Cosmological Constant Problem (CCP) is proposed and discussed within the multiverse approach of Quantum Cosmology. It is assumed that each member of the ensemble of universes has a characteristic scale a that can be used as ...
Vesselin G. Gueorguiev, Andre Maeder
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Can the quantum vacuum fluctuations really solve the cosmological constant problem? [PDF]
European Physical Journal C: Particles and Fields, 2020 Recently it has been argued that a correct reading of the quantum fluctuations of the vacuum could lead to a solution to the cosmological constant problem.
Gabriel R. Bengochea +3 more
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Renormalizing the vacuum energy in cosmological spacetime: implications for the cosmological constant problem [PDF]
European Physical Journal C: Particles and Fields, 2022 The renormalization of the vacuum energy in quantum field theory (QFT) is usually plagued with theoretical conundrums related not only with the renormalization procedure itself, but also with the fact that the final result leads usually to very large ...
Cristian Moreno-Pulido +1 more
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Solution of the cosmological constant problem within holographic cosmology [PDF]
Physics Letters B, 2020 Within the holographic cosmology paradigm, specifically the model of McFadden and Skenderis, but more generally than that, the cosmological constant is found to naturally flow from a large value, to a small value, which can even be as low as the needed ...
Horatiu Nastase
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A technical analog of the cosmological constant problem and a solution thereof [PDF]
Journal of High Energy Physics, 2021 The near vanishing of the cosmological constant is one of the most puzzling open problems in theoretical physics. We consider a system, the so-called framid, that features a technically similar problem.
Ioanna Kourkoulou +2 more
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Cosmic clues: DESI, dark energy, and the cosmological constant problem [PDF]
Journal of High Energy PhysicsSeveral attempts to solve the cosmological constant problem, which concerns the value of the cosmological constant being extremely smaller than the Standard Model mass scales, have introduced a scalar field with a very flat potential that can be ...
Wen Yin
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