相关论文: A Question About Standard Cosmology and Extremely …
The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or…
Newtonian Cosmology is commonly used in astrophysical problems, because of its obvious simplicity when compared with general relativity. However it has inherent difficulties, the most obvious of which is the non-existence of a well-posed…
The strong equivalence principle is extended in application to averaged dynamical fields in cosmology to include the role of the average density in the determination of inertial frames. The resulting cosmological equivalence principle is…
We present here an overview of our basic understanding and recent developments on spacetime singularities in the Einstein theory of gravity. Several issues related to physical significance and implications of singularities are discussed.…
A generalized quintessence model is presented which corresponds to a richer vacuum structure that, besides a time-dependent, slowly varying scalar field, contains a varying cosmological term. From first principles we determine a number of…
For two decades the hot big-bang model as been referred to as the standard cosmology -- and for good reason. For just as long cosmologists have known that there are fundamental questions that are not answered by the standard cosmology and…
Matrix theory is a proposed non-perturbative definition of superstring theory in which space is emergent. We begin a study of cosmology in the context of matrix theory. Specifically, we show that matrix theory can lead to an emergent…
The total red shift $z$ might be recast as a combination of the expansion red shift and a static shift due to the energy-momentum tensor non-conservation of a photon propagating through Electro-Magnetic (EM) fields. If massive, the photon…
We identify a "supernova rate problem": the measured cosmic core-collapse supernova rate is a factor of ~ 2 smaller (with significance ~ 2 sigma) than that predicted from the measured cosmic massive-star formation rate. The comparison is…
In a universe where, according to the standard cosmological models, some 97% of the total mass-energy is still "missing in action" it behooves us to spend at least a little effort critically assessing and exploring radical alternatives.…
The latest astrophysical data on the Supernova luminosity--distance -- redshift relations, primordial nucleosynthesis, value of Cosmic Microwave Background--temperature, and baryon asymmetry are considered as an evidence of relative…
While many observations support the validity of Einstein's general relativity as the theory of gravity, there are yet many that suggest the presence of new physics. In order to explain the high-redshift supernovae Ia observations together…
The existence of extremely dark and compact astronomical bodies is by now a well established observational fact. On the other hand, classical General Relativity predicts the existence of black holes which fit very well with the…
I will review some results of observational cosmology which critically cast doubt upon the foundations of the standard cosmology: 1) The redshifts of the galaxies are due to the expansion of the Universe; 2) The cosmic microwave background…
We study the implications of a combined analysis of cosmic standard candles and standard rulers on the viability of cosmological models beyond the cosmological concordance model. To this end, we employ well-established data in the form of…
We discuss various space-time metrics which are compatible with Einstein's equations and a previously suggested cosmology with a finite total mass. In this alternative cosmology the matter density was postulated to be a spatial delta…
Here we present some critical discussions about the systematic uncertainty by dust extinction in the recent cosmological results of high-redshift Type Ia supernovae. First we argue that the currently available data do not robustly exclude…
Can modern cosmological observations be reconciled with a general-relativistic Universe without an anti-gravitating energy source? Usually, the answer to this question by cosmologists is in the negative, and it is commonly believed that the…
The experimental evidence that the equation of state (EOS) of the dark energy (DE) could be evolving with time/redshift (including the possibility that it might behave phantom-like near our time) suggests that there might be dynamical DE…
The spatially homogeneous, isotropic Standard Cosmological Model appears to describe our Universe reasonably well. However, Einstein's equations allow a much larger class of cosmological solutions. Theorems originally due to Penrose and…