112 citations · 989 across the 71 of their papers we have counts for
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Possible relationship between initial conditions for inflation and past geodesic incompleteness of the inflationary spacetime
Alexander Kaganovich
According to the Borde-Guth-Vilenkin (BGV) theorem an expanding region of spacetime cannot be extended to the past beyond some boundary . Therefore, the inflationary u…
Non-Canonical Volume-Form Formulation of Modified Gravity Theories and Cosmology
David Benisty, Eduardo I. Guendelman, Alexander Kaganovich +2
A concise description is presented of the basic features of the formalism of non-canonical spacetime volume-forms and its application in modified gravity theories and cosmology. Th…
Modified Gravity Theories Based on the Non-Canonical Volume-Form Formalism
David Benisty, Eduardo Guendelman, Alexander Kaganovich +2
We present a concise description of the basic features of gravity-matter models based on the formalism of non-canonical spacetime volume-forms in its two versions: the method of no…
Neutrino generated dynamical dark energy with no dark energy field
E. I. Guendelman, A. B. Kaganovich
Dynamical dark energy (DE) phenomenon emerges as a geometrical effect accompanying the cosmological expansion of nonrelativistic fermionic matter. This occurs without the need for…
Physical Consequences of a Theory with Dynamical Volume Element
E. I. Guendelman, A. B. Kaganovich
We survey motivation, basic ideas and physical consequences of a theory where the underlying action involves terms both with the usual volume element and with the…
Transition to Zero Cosmological Constant and Phantom Dark Energy as Solutions Involving Change of Orientation of Space-Time Manifold
E. I. Guendelman, A. B. Kaganovich
Solutions with degenerate metric ( or ) in the first order formalism (FOF) are physically acceptable: they may describe topology changes (Horowitz) and red…
Absence of the Fifth Force Problem in a Model with Spontaneously Broken Dilatation Symmetry
E. I. Guendelman, A. B. Kaganovich
A scale invariant model containing dilaton and dust (as a model of matter) is studied where the shift symmetry is spontaneously broken at the classical level due…
Initial Singularity, Lambda-Problem and Crossing the Phantom Divide in Scale Invariant TMT Model
E. I. Guendelman, A. B. Kaganovich
In the framework of the scale invariant model of the Two Measures Field Theory (TMT), we study the dilaton-gravity sector in the context of spatially flat FRW cosmology. The scale…
Fine Tuning Free Paradigm of Two Measures Theory: K-Essence, Absence of Initial Singularity of the Curvature and Inflation with Graceful Exit to Zero Cosmological Constant State
E. I. Guendelman, A. B. Kaganovich
The dilaton-gravity sector of the Two Measures Field Theory (TMT)is explored in detail in the context of cosmology. The model possesses scale invariance which is spontaneously brok…
k-Essence, Avoidance of the Weinberg's Cosmological Constant No-Go Theorem and Other Dark Energy Effects of Two Measures Field Theory
E. I. Guendelman, A. B. Kaganovich
The dilaton-gravity sector of the Two Measures Field Theory (TMT) is explored in detail in the context of cosmology. The dilaton ϕdependence of the effective Lagrangian appears onl…
Exotic Low Density Fermion States in the Two Measures Field Theory: Neutrino Dark Energy
E. I. Guendelman, A. B. Kaganovich
We study a new field theory effect in the cosmological context in the Two Measures Field Theory (TMT). TMT is an alternative gravity and matter field theory where the gravitational…
Dark energy, dark matter and fermion families in the two measures theory
E. I. Guendelman, A. B. Kaganovich
A field theory is proposed where the regular fermionic matter and the dark fermionic matter are different states of the same "primordial" fermion fields. In regime of the fermion d…
Some Cosmological Applications of Two Measures Theory
E. I. Guendelman, A. B. Kaganovich
Scale invariance is considered in the context of a gravitational theory where the action, in the first order formalism, is of the form S = \int L_{1} Φd^4x + \int L_{2}\sqrt{-g}d^4…
Is Cosmic Coincidence a Consequence of a Law of Nature?
E. I. Guendelman, A. B. Kaganovich
A field theory is proposed where the regular fermionic matter and the dark fermionic matter are different states of the same "primordial" fermion fields. In regime of the fermion d…
Dynamical measure and field theory models free of the cosmological constant problem
E. I. Guendelman, A. B. Kaganovich
Summary of abstract Field theory models including gauge theories with SSB are presented where the energy density of the true vacuum state (TVS) is zero without fine tuning. The abo…
Dominance of a Dynamical Measure and Disappearance of the Cosmological Constant
E. I. Guendelman, A. B. Kaganovich
We consider an action which consists of two terms: the first S_{1}=\int L_{1}Φd^{4}x and the second S_{2}=\int L_{2}\sqrt{-g}d^{4}x where Φis a measure which has to be determined d…
From inflation to a zero cosmological constant phase without fine tuning
E. I. Guendelman, A. B. Kaganovich
We show that it is possible to obtain inflation and also solve the cosmological constant problem. The theory is invariant under changes of the Lagrangian density to .…
Gravitational theory without the cosmological constant problem, symmetries of space-filling branes and higher dimensions
E. I. Guendelman, A. B. Kaganovich
We showed that the principle of nongravitating vacuum energy, when formulated in the first order formalism, solves the cosmological constant problem. The most appealing formulation…
Gravitational Theory without the Cosmological Constant Problem
E. I. Guendelman, A. B. Kaganovich
We develop the principle of nongravitating vacuum energy, which is implemented by changing the measure of integration from to an integration in an internal space…
The Principle of Non-Gravitating Vacuum Energy and some of its consequences
E. I. Guendelman, A. B. Kaganovich
For Einstein's General Relativity (GR) or the alternatives suggested up to date the vacuum energy gravitates. We present a model where a new measure is introduced for integration o…
Kaluza -- Klein Quantum Cosmology with Primordial Negative Cosmological Constant
E. I. Guendelman, A. B. Kaganovich
In many interesting models, including superstring theories, a negative vacuum energy is predicted. Although this effect is usually regarded as undesirable from a cosmological point…