On the Nature and Values of the Gravitational and Cosmological Constants (original) (raw)
Related papers
The dynamics of vacuum, gravity and matter: Implications on the fundamental constants
arXiv (Cornell University), 2023
The possibility that the vacuum energy density (VED) ρvac could be time dependent in the expanding Universe is intuitively more reasonable than just a rigid cosmological constant for the entire cosmic history. The dynamics of ρvac = ρvac(H) as a function of the Hubble rate, H(t), most likely contributes to alleviate cosmological problems and tensions, having also implications on the so-called fundamental 'constants' of Nature, which should be slowly drifting with the cosmic expansion owing to the fluctuations of the quantum vacuum. This includes the gravitational 'constant' G, but also the gauge and Yukawa couplings as well as the particle masses themselves (both of dark matter and baryonic matter). The subtle exchange of energy involved is the basis for the "micro and macro connection". Herein, I discuss not only this connection as a possibility but show that it is in fact a generic prediction of QFT in cosmological spacetime which is fully compatible with general covariance. This fact has not been pointed out until recently when an appropriate renormalization framework for the VED has been found which is free from the usual conundrums associated with the cosmological constant problem.
Science, 1999
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 physics of a small (and potentially nonzero) vacuum energy.
The Demystification of the Mystery of the Cosmological Constant
The article proposes a mechanism to eliminate the difference between the experimental values of the cosmological constant and its theoretical predictions made within the framework of the theory of elementary particles based on the concept of the neutron cluster (complex). It is shown that the quantum vacuum is unstable with respect to the formation of giant fluctuations in the density of particles (clusters) formed as a result of the birth of virtual pairs. The reverse annihilation of pairs does not occur due to the divergence of the components of the pair under the action of tidal forces in the inhomogeneous gravitational field created by the particles themselves. This resembles the mechanism underlying the evaporation of black holes. The formation of a cluster is described by the example of neutrons. As it was shown earlier in the author's works, the neutron cluster can be considered the initial stage of the formation of a neutron star. This concept made it possible to reconcile the predictions obtained within the frameworks of elementary particle theory, cosmology, and traditional quantum mechanics. The result obtained is fundamental both for cosmology and for the theory of elementary particles.
A resolution of the cosmological constant problem
The standard calculation of vacuum energy or zero point energy is in strong disagreement with observation. We suggest that this discrepancy is caused by the incomplete quantization of standard field theory. The vacuum energy calculation for fermions shows an unacceptable asymmetry between particles and anti-particles, which has to be corrected by an additional quantization step that reverses the order of the anti-particle operators. Boson fields can be handled similarly, but have to be expanded first in terms of bilinear fermion operators. After the full quantization the vacuum energy vanishes. This does not violate the Casimir effect as this can be explained without reference to the vacuum energy, as Jaffe has demonstrated elsewhere.
Some Dynamical Effects of the Cosmological Constant
Modern Physics Letters A, 2000
Newton's law gets modified in the presence of a cosmological constant by a small repulsive term (antigravity) that is proportional to the distance. Assuming a value of the cosmological constant consistent with the recent SnIa data (Λ≃10-52 m-2), we investigate the significance of this term on various astrophysical scales. We find that on galactic scales or smaller (less than a few tens of kpc), the dynamical effects of the vacuum energy are negligible by several orders of magnitude. On scales of 1 Mpc or larger however we find that the vacuum energy can significantly affect the dynamics. For example we show that the velocity data in the local group of galaxies correspond to galactic masses increased by 35% in the presence of vacuum energy. The effect is even more important on larger low density systems like clusters of galaxies or superclusters.
The Source of the Gravitational Constant at the
In general relativity, gravity is attributed to the geometry of space-time. Literature states that the gravitational constant (G) originates at the Planck scale. The Compton wavelength (Planck length) L=(\h*G/C^3)^.5 is 1.61e-35 meters and this is associated with the Planck energy 1.2e22 MeV. This energy is far greater than the energy of a proton and the space surrounding each proton is far greater than the Compton wavelength. It is generally accepted that the Compton wavelength is nature’s response to geometry and mass at the quantum scale. In this paper, the author discusses the hierarchy of interactions with a focus on gravity, propose a low energy scale source of the gravitational constant, and identify a more fundamental coupling constant with the value 1/exp(90). A unique cellular approach is used to model expansion. A cell is the space associated with a proton mass and has cosmological properties that allow it to represent the universe geometrically. Each cell has an initial radius of 7.22e-14 meters and, if it expands according to the concordance model with WMAP parameters, its current value is 0.54 meters. WMAP data allows one to estimate the numbers of protons in the universe. By using this approach, it is possible to compare the kinetic energy that expands cells with potential energy. Implications for the fraction of dark energy, baryons and cold dark matter are discussed. Several examples involving the use of the value 1/exp(90) are presented that demonstrate how cellular values predict large scale observations. Key Words: gravitational constant, cellular approach, cosmology, WMAP.
2014
A mechanism for suppressing the cosmological constant is developed, based on an analogy with a superconducting phaseshift in which free fermions coupled perturbatively to a weak gravitational field are in an unstable false vacuum state. The coupling of the fermions to the gravitational field generates fermion condensates with zero momentum and a phase transition induces a nonperturbative transition to a true vacuum state by producing a positive energy gap ∆ in the vacuum energy, identified with √ Λ, where Λ is the cosmological constant. In the strong coupling limit a large cosmological constant induces a period of inflation in the early universe, followed by a weak coupling limit in which √ Λ vanishes exponentially fast as the universe expands due to the dependence of the energy gap on the density of Fermi
The cosmological constant problem
Astronomical observations indicate that the cosmological constant is many orders of magnitude smaller than estimated in modern theories of elementary particles. After a brief review of the history of this problem, five different approaches to its solution are described.
A Solution to the cosmological constant problem
Arxiv preprint astro-ph/9606071, 1996
According to general relativity, the present analysis shows on geometrical grounds that the cosmological constant problem is an artifact due to the unfounded link of this fundamental constant to vacuum energy density of quantum fluctuations.