scholarly journals Flat Space Cosmology as a Model of Light Speed Cosmic Expansion—Implications for the Vacuum Energy Density

2018 ◽  
Vol 09 (10) ◽  
pp. 2008-2020 ◽  
Author(s):  
Eugene Terry Tatum ◽  
U. V. S. Seshavatharam
Keyword(s):  
Energy Density ◽  
Vacuum Energy ◽  
Flat Space ◽  
Vacuum Energy Density ◽  
Cosmic Expansion ◽  
Light Speed

scholarly journals BAGS AND CONFINEMENT GOVERNED BY SPONTANEOUS SYMMETRY BREAKING OF SCALE INVARIANCE

2010 ◽  
Vol 25 (22) ◽  
pp. 4195-4220 ◽  
Author(s):  
E. I. GUENDELMAN
Keyword(s):  
Energy Density ◽  
Symmetry Breaking ◽  
Spontaneous Symmetry Breaking ◽  
Gauge Field ◽  
Scale Invariance ◽  
Vacuum Energy ◽  
Equations Of Motion ◽  
Flat Space ◽  
Vacuum Energy Density ◽  
Conformally Invariant

A general coordinate invariant theory is constructed where confinement of gauge fields and gauge dynamics in general is governed by the spontaneous symmetry breaking (s.s.b.) of scale invariance. The model uses two measures of integration in the action, the standard [Formula: see text] where g is the determinant of the metric and another measure Φ independent of the metric. To implement scale invariance, a dilaton field is introduced. Using the first-order formalism, curvature (ΦR and [Formula: see text]) terms, gauge field term ([Formula: see text] and [Formula: see text]) and dilaton kinetic terms are introduced in a conformally invariant way. Exponential potentials for the dilaton break down (softly) the conformal invariance down to global scale invariance, which also suffers s.s.b. after integrating the equations of motion. The model has a well-defined flat space limit. As a result of the s.s.b. of scale invariance phases with different vacuum energy density appear. Inside the bags, that is in the regions of larger vacuum energy density, the gauge dynamics is normal, that is nonconfining, while for the region of smaller vacuum energy density, the gauge field dynamics is confining. Likewise, the dynamics of scalars, like would be Goldstone bosons, is suppressed inside the bags.

scholarly journals Remaining Problems in Interpretation of the Cosmic Microwave Background

2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Hans-Jörg Fahr ◽  
Michael Sokaliwska
Keyword(s):  
Energy Density ◽  
Vacuum Energy ◽  
Boltzmann Distribution ◽  
Vacuum Energy Density ◽  
Microwave Background ◽  
Equilibrium Conditions ◽  
Theoretical Understanding ◽  
Cosmic Expansion ◽  
Star Formation In Galaxies ◽  
Planck Law

By three independent hints it will be demonstrated that still at present there is a substantial lack of theoretical understanding of the CMB phenomenon. One point, as we show, is that at the phase of the recombination era one cannot assume complete thermodynamic equilibrium conditions but has to face both deviations in the velocity distributions of leptons and baryons from a Maxwell-Boltzmann distribution and automatically correlated deviations of photons from a Planck law. Another point is that at the conventional understanding of the CMB evolution in an expanding universe one has to face growing CMB temperatures with growing look-back times. We show, however, here that the expected CMB temperature increases would be prohibitive to star formation in galaxies at redshifts higher than z=2 where nevertheless the cosmologically most relevant supernovae have been observed. The third point in our present study has to do with the assumption of a constant vacuum energy density which is required by the present ΛCDM-cosmology. Our studies here rather lead to the conclusion that cosmic vacuum energy density scales with the inverse square of the cosmic expansion scale R=R(t). Thus we come to the conclusion that with the interpretation of the present-day high quality CMB data still needs to be considered carefully.

scholarly journals LOCAL CONTRIBUTION OF A QUANTUM CONDENSATE TO THE VACUUM ENERGY DENSITY

2003 ◽  
Vol 18 (10) ◽  
pp. 683-690 ◽  
Author(s):  
GIOVANNI MODANESE
Keyword(s):  
Energy Density ◽  
Vacuum Energy ◽  
Casimir Effect ◽  
Landau Equation ◽  
Vacuum Energy Density ◽  
Negative Effects ◽  
Ginzburg Landau ◽  
Physical Conditions ◽  
Local Contribution ◽  
Gravitational Vacuum

We evaluate the local contribution gμνL of coherent matter with Lagrangian density L to the vacuum energy density. Focusing on the case of superconductors obeying the Ginzburg–Landau equation, we express the relativistic invariant density L in terms of low-energy quantities containing the pairs density. We discuss under which physical conditions the sign of the local contribution of the collective wave function to the vacuum energy density is positive or negative. Effects of this kind can play an important role in bringing the local changes in the amplitude of gravitational vacuum fluctuations — a phenomenon reminiscent of the Casimir effect in QED.

scholarly journals Brownian motion and polarized three-dimensional quantum vacuum

2021 ◽  
Vol 67 (4 Jul-Aug) ◽  
Author(s):  
Davide Fiscaletti
Keyword(s):  
Dark Matter ◽  
Brownian Motion ◽  
Energy Density ◽  
Nonlinear Model ◽  
Vacuum Energy ◽  
Three Dimensional ◽  
Vacuum Energy Density ◽  
Quantum Vacuum ◽  
Virtual Particles ◽  
Fundamental Entity

A nonlinear model of Brownian motion is developed in a three-dimensional quantum vacuum defined by a variable quantum vacuum energy density corresponding to processes of creation/annihilation of virtual particles. In this model, the polarization of the quantum vacuum determined by a perturbative fluctuation of the quantum vacuum energy density associated with a fluctuating viscosity, which mimics the action of dark matter, emerges as the fundamental entity which generates the Brownian motion.

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