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The Cosmological Constant [PDF]

String Phenomenology, 2002
Various contributions to the cosmological constant are discussed and confronted with its recent measurement. We briefly review different scenarious -- and their difficulties -- for a solution of the cosmological constant problem.Comment: Lecture given at
Ellwanger, U.
core   +4 more sources

Gauge-Dependent Cosmological "Constant" [PDF]

Classical and Quantum Gravity, 2004
When the cosmological constant of spacetime is derived from the 5D induced-matter theory of gravity, we show that a simple gauge transformation changes it to a variable measure of the vacuum which is infinite at the big bang and decays to an ...
Adler R, Bahram Mashhoon, Campbell J, Carroll S M, Green M B, Magaard L, Mashhoon B, Ng Y J, Overduin J M, Padmanabhan T, Paul S Wesson, Romero C, Weinberg S, Wesson P S, Wesson P S, West P, Youm D, Youm D   +17 more
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Mirror QCD and Cosmological Constant

Universe, 2017
An analog of Quantum Chromo Dynamics (QCD) sector known as mirror QCD (mQCD) can affect the cosmological evolution due to a non-trivial contribution to the Cosmological Constant analogous to that induced by the ground state in non-perturbative QCD.
Roman Pasechnik, George Prokhorov, Oleg Teryaev   +2 more
doaj   +4 more sources

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
doaj   +3 more sources

Proposal for a Constant Cosmological Constant [PDF]

Physics Letters B, 2000
It is proposed that the apparent positive acceleration of the cosmological scale factor is due to the vacuum energy of an incomplete chiral phase transition in a hidden SU(2) sector.
Abbott, Albrecht, Alcock, Appelquist, Berezhiani, Burles, Caldwell, Campbell, Carroll, Chan, Chen, Chodos, Coble, Coleman, Coleman, Cormier, Dodelson, Dolan, Frieman, Frieman, Frieman, Fuller, Guth, Haim Goldberg, Hill, Hill, Iacobson, Iwasaki, Kajantie, Kofman, Kogut, Kogut, Kolda, Linde, Lisi, Mawhinney, Olive, Olive, Paterson, Peebles, Perlmutter, Perlmutter, Perlmutter, Peskin, Pisarski, Pokrovskii, Riess, Sannino, Shiu, Shtanov, Singh, Vafa, Wirstam, Witten, Yamagishi, Zlatev   +55 more
core   +4 more sources

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, Miguel. A. García-Aspeitia, Humberto Martínez-Huerta, Alberto Hernández-Almada   +3 more
doaj   +1 more source

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
doaj   +1 more source

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
doaj   +1 more source

Solar System-scale Interferometry on Fast Radio Bursts Could Measure Cosmic Distances with Subpercent Precision

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
doaj   +1 more source

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, A. M. Vicente, J. F. Jesus, R. F. L. Holanda   +3 more
doaj   +1 more source