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200 papers

Possibility of gravitational repulsion in General Relativity is discussed and astronomical data in favor of cosmological acceleration are described. The problem of vacuum energy is emphasized and possible ways of its solution are indicated.…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-19 A. D. Dolgov

Recent experimental results find strong indications that the universe is flat, while other experimental results from supernovae Ia observations have been interpreted to show that, not only that there is an accelerating expansion of the…

Astrophysics · Physics 2012-08-27 George A. Baker,

The modern Everett interpretation of quantum mechanics describes an emergent multiverse. The goal of this paper is to provide a perspicuous characterisation of how the multiverse emerges making use of a recent account of (weak) ontological…

Quantum Physics · Physics 2026-03-12 Alexander Franklin

Scientific discussions of the arrow of time often get quite confusing due to highly complex systems they deal with. Popular literature then often coveys messages that tend to get lost in translation. The purpose of this note is to demystify…

Popular Physics · Physics 2024-08-29 Zura Kakushadze

Lagrangian particles in turbulence separate away from each other faster in the backward in time direction as compared to forward in time. In this work, we show that time irreversibility is kinematically rooted in the fact that, when viewed…

Fluid Dynamics · Physics 2025-08-20 Ron Shnapp

We propose an explanation for the present accelerated expansion of the universe that does not invoke dark energy or a modification of gravity and is firmly rooted in inflationary cosmology.

High Energy Physics - Theory · Physics 2007-05-23 Edward W. Kolb , Sabino Matarrese , Alessio Notari , Antonio Riotto

Are time-travels possible? is the past still existing? and is the future already existing? We try to give an answer to these an other questions concerning the properties of time and the close connection (but deep physical difference)…

General Relativity and Quantum Cosmology · Physics 2025-07-09 Maurizio Gasperini

The evidence of the acceleration of universe at present time has lead to investigate modified theories of gravity and alternative theories of gravity, which are able to explain acceleration from a theoretical viewpoint without the need of…

High Energy Physics - Theory · Physics 2011-05-05 Gianluca Allemandi , Andrzej Borowiec , Mauro Francaviglia

In the context of a parametric theory (with the time being a dynamical variable) we consider the coupling between the quantum vacuum and the background gravitation that pervades the universe (unavoidable because of the universality of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Antonio F. Ranada , Alfredo Tiemblo

We historically trace various non-conventional explanations for the origin of the cosmic microwave background and discuss their merit, while analyzing the dynamics of their rejection, as well as the relevant physical and methodological…

History and Philosophy of Physics · Physics 2017-05-24 Milan M. Cirkovic , Slobodan Perovic

Several physical concepts, including the concept of time, are clarified herein by taking into account existing experimental data. In addition, the missing links among these physical concepts are established. This allows us to take another…

General Physics · Physics 2022-10-04 Robert Sadykov

We investigate the recent - low redshift - expansion history of the universe using the most recent observational data. Using only data from 42 measurements of $f_{gas}$ in clusters, we found that cosmic acceleration could have already…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Victor H. Cardenas , Carla Bernal , Alexander Bonilla

Based on the conjecture that rather than the second law of thermodynamics inevitably be breached as matter approaches a big crunch or a black hole singularity, the order of events should reverse, a model of the universe that resolves a…

General Physics · Physics 2007-05-23 Peter Lynds

Microphysical laws are time reversible, but macrophysics, chemistry and biology are not. This chapter explores how this asymmetry (a classic example of a broken symmetry) arises due to the cosmological context, where a non-local Direction…

General Relativity and Quantum Cosmology · Physics 2020-03-18 George F R Ellis , Barbara Drossel

A time-dependent model of space-time is used to suggest simple explanations for the increasing of the Astronomical unit, as well as the increasing of the distance from the Earth to the Moon. The Pioneer anomaly is also considered.

General Relativity and Quantum Cosmology · Physics 2010-03-13 Ll. Bel

The problem of explaining the acceleration of the expansion of the universe and the observational and theoretical difficulties associated with dark matter and dark energy are discussed. The possibility that Einstein gravity does not…

Astrophysics · Physics 2007-05-23 J. W. Moffat

I present a brief review of astro-ph/0406099, which argues that there is a limit on the number of efolds of inflation which are observable in a universe which undergoes an eternally accelerated expansion in the future. Such an acceleration…

High Energy Physics - Theory · Physics 2007-05-23 Matthew Kleban

Recent data suggest that the Universe could be positively curved. Combined with an inflationary stage, this might lead to a curvature bounce instead of the Big Bang. The background evolution is presented, as a function of the parameters…

General Relativity and Quantum Cosmology · Physics 2021-01-20 Cyril Renevey , Aurélien Barrau , Killian Martineau , Selim Touati

It is a remarkable fact that all processes occurring in the observable Universe are irreversible, whereas the equations in which the laws of physics are formulated are invariant under time reversal. The emergency of irreversibility from the…

Popular Physics · Physics 2009-12-10 Gustavo E. Romero

The new explanation of global tendencies (in particular, of natural calamities and other disasters, taking place in present time in different countries) is suggested.

Popular Physics · Physics 2008-01-22 Viktor I. Shapovalov , Nickolay V. Kazakov