The Role of Energy Conservation and Vacuum Energy in the Evolution of the Universe

2010 ◽  
Vol 15 (2) ◽  
pp. 153-176 ◽  
Author(s):  
Jan M. Greben
Keyword(s):  
Energy Conservation ◽  
Vacuum Energy ◽  
Evolution Of The Universe ◽  
The Universe

scholarly journals The Energy Conservation in Our Universe and the Pressureless Dark Energy

2015 ◽  
Vol 2015 ◽  
pp. 1-4
Author(s):  
Man Ho Chan
Keyword(s):  
Dark Energy ◽  
Energy Conservation ◽  
Total Energy ◽  
Dark Energy Model ◽  
Vacuum Energy ◽  
Energy Model ◽  
Universe Expansion ◽  
The Law ◽  
The Universe

Recent observations confirm that a certain amount of unknown dark energy exists in our universe so that the current expansion of our universe is accelerating. It is commonly believed that the pressure of the dark energy is negative and the density of the dark energy is almost a constant throughout the universe expansion. In this paper, we show that the law of energy conservation in our universe has to be modified because more vacuum energy is gained due to the universe expansion. As a result, the pressure of dark energy would be zero if the total energy of our universe is increasing. This pressureless dark energy model basically agrees with the current observational results.

scholarly journals Inflation from Supersymmetry Breaking

Universe ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 30 ◽  
Author(s):  
Ignatios Antoniadis
Keyword(s):  
Supersymmetry Breaking ◽  
Vacuum Energy ◽  
Scalar Potential ◽  
Small Field ◽  
Slow Roll ◽  
Cosmological Observations ◽  
Interesting Class ◽  
The Universe ◽  
R Symmetry

I discuss the possibility that inflation is driven by supersymmetry breaking, with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Imposing an R-symmetry to satisfy the slow-roll conditions, avoiding the so-called η -problem, leads to an interesting class of small field inflation models, characterised by an inflationary plateau around the maximum of scalar potential near the origin, where R-symmetry is restored with the inflaton rolling down to a minimum, describing the present phase of the Universe. Inflation can be driven by either an F- or a D-term, while the minimum has a positive tuneable vacuum energy. The models agree with cosmological observations and, in the simplest case, predict a rather small tensor-to-scalar ratio of primordial perturbations. This talk is an extended version of an earlier review (Antoniadis, 2018).

scholarly journals Challenges in Supersymmetric Cosmology

Symmetry ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 468
Author(s):  
Ignatios Antoniadis ◽  
Auttakit Chatrabhuti
Keyword(s):  
Vacuum Energy ◽  
Scalar Potential ◽  
Low Energy ◽  
Small Field ◽  
Slow Roll ◽  
Cosmological Observations ◽  
Interesting Class ◽  
The Universe ◽  
R Symmetry

We discuss the possibility that inflation is driven by supersymmetry breaking with the scalar component of the goldstino superfield (sgoldstino) playing the role of the inflaton and charged under a gauged U ( 1 ) R-symmetry. Imposing a linear superpotential allows us to satisfy easily the slow-roll conditions, avoiding the so-called η -problem, and leads to an interesting class of small field inflation models, characterised by an inflationary plateau around the maximum of the scalar potential near the origin, where R-symmetry is restored with the inflaton rolling down to a minimum describing the present phase of the Universe. Inflation can be driven by either an F- or a D-term, while the minimum has a positive tuneable vacuum energy. The models agree with cosmological observations and in the simplest case predict a rather small tensor-to-scalar ratio of primordial perturbations. We propose a generalisation of Fayet-Iliopoulos model as a microscopic model leading to this class of inflation models at low energy.

Challenges in string and supersymmetric cosmology

2021 ◽  
pp. 2044030
Author(s):  
Ignatios Antoniadis ◽  
Auttakit Chatrabhuti
Keyword(s):  
Supersymmetry Breaking ◽  
Vacuum Energy ◽  
Scalar Potential ◽  
Small Field ◽  
Slow Roll ◽  
Cosmological Observations ◽  
Interesting Class ◽  
The Universe ◽  
R Symmetry

We discuss the possibility that inflation is driven by supersymmetry breaking with the superpartner of the goldstino (sgoldstino) playing the role of the inflaton. Imposing an R-symmetry allows to satisfy easily the slow-roll conditions, avoiding the so-called [Formula: see text]-problem, and leads to an interesting class of small field inflation models, characterized by an inflationary plateau around the maximum of the scalar potential near the origin, where R-symmetry is restored with the inflaton rolling down to a minimum describing the present phase of the Universe. Inflation can be driven by either an [Formula: see text]- or a [Formula: see text]-term, while the minimum has a positive tuneable vacuum energy. The models agree with cosmological observations and in the simplest case predict a rather small tensor-to-scalar ratio of primordial perturbations.

scholarly journals Dynamics and Clusters of Galaxies

1974 ◽  
Vol 62 ◽  
pp. 273-284
Author(s):  
D. G. Saari
Keyword(s):  
Virial Theorem ◽  
Gravitational Force ◽  
Clusters Of Galaxies ◽  
Expanding Universe ◽  
Evolution Of The Universe ◽  
Mathematical Probability ◽  
The Masses ◽  
The Universe

Under the assumption that the inverse square central force law is a good approximation to the gravitational force, at least for large distances, the different possibilities for the evolution of the Universe are sketched. Several of the possibilities lead naturally to a dynamical classification of clusters of galaxies in an expanding universe. In one of the classifications the galaxies must define configurations which are functions of the masses. The virial theorem approach of determining masses of galaxies in a cluster is briefly examined. Some tentative statements concerning a dynamical explanation of the local hypothesis for quasars are advanced. Finally, the role of mathematical probability in predicting the behavior of the Universe is discussed.

scholarly journals ON TOPOLOGICAL DEFECTS AND COSMOLOGICAL CONSTANT

2014 ◽  
Vol 29 (01) ◽  
pp. 1450007 ◽  
Author(s):  
B. RAYCHAUDHURI ◽  
F. RAHAMAN ◽  
M. KALAM
Keyword(s):  
Cosmological Constant ◽  
Vacuum Energy ◽  
Ad Hoc ◽  
Topological Defects ◽  
Field Equations ◽  
Theoretical Support ◽  
Accelerating Expansion ◽  
Expansion Of The Universe ◽  
The Universe

Einstein introduced cosmological constant in his field equations in an ad hoc manner. Cosmological constant plays the role of vacuum energy of the universe which is responsible for the accelerating expansion of the universe. To give a theoretical support, it remains an elusive goal to modern physicists. We provide a prescription to obtain cosmological constant from the phase transitions of the early universe when topological defects, namely monopole might have existed.

Sign in / Sign up

Export Citation Format

Share Document