Results 81 to 90 of about 406,699 (273)
Inflation with a negative cosmological constant [PDF]
Physical Review D, 2009 We find a unique way of realizing inflation through cyclic phases in an universe with negative vacuum energy. According to the second law of thermodynamics entropy monotonically increases from cycle to cycle, typically by a constant factor. This means that the scale factor at the same energy density in consecutive cycles also increases by a constant ...
Anupam Mazumdar +2 more
openaire +4 more sources
, 2006 These lectures present a brief review of inflationary cosmology, provide an overview of the theory of cosmological perturbations, and then focus on the conceptual problems of the current paradigm of early universe cosmology, thus motivating an ...
Robert Brandenberger +1 more
core +3 more sources
Inflation and Cosmological Perturbations [PDF]
, 2010 56 pages, 5 figures; Lectures given at the Second TRR33 Winter School on cosmology, Passo del Tonale (Italy), December ...
openaire +6 more sources
Inflationary Cosmology and Quantization Ambiguities in Semi-Classical Loop Quantum Gravity [PDF]
, 2004 In loop quantum gravity, modifications to the geometrical density cause a self-interacting scalar field to accelerate away from a minimum of its potential.
A. Ashtekar +30 more
core +3 more sources
Higgs Inflation and the Cosmological Constant [PDF]
Acta Physica Polonica B, 2014 The Higgs not only induces the masses of all SM particles, the Higgs, given its special mass value, is the natural candidate for the inflaton and in fact is ruling the evolution of the early universe, by providing the necessary dark energy which remains the dominant energy density.
openaire +5 more sources
Journal of High Energy Physics, 2021 We consider multiverse models in two-dimensional linear dilaton-gravity theories as toy models of false vacuum eternal inflation. Coupling conformal matter we calculate the Von Neumann entropy of subregions. When these are sufficiently large we find that
Sergio E. Aguilar-Gutierrez +4 more
doaj +1 more source
, 2002 We review the broad status of cosmology and discuss a model of fluctuational cosmology in which the universe is created in a phase transition like phenomenon mimicking inflation, and which further consistently explains latest observations like the ever ...
B.G. Sidharth +28 more
core +3 more sources
Cosmological perturbations without inflation [PDF]
Classical and Quantum Gravity, 2016 A particularly attractive feature of inflation is that quantum fluctuations inthe inflaton field may have seeded inhomogeneities in the cosmic microwavebackground (CMB) and the formation of large-scale structure. In this paper,we demonstrate that a scalar field with zero active mass, i.e., with anequation of state $\rho+3p=0$, where $\rho$ and $p$ are ...
openaire +5 more sources
Towards a cosmological dual to inflation
Physical Review D, 2011 We derive all single-field cosmologies with unit sound speed that generate scale invariant curvature perturbations on a dynamical attractor background. We identify three distinct phases: slow-roll inflation; a slowly contracting adiabatic ekpyrotic phase, described by a rapidly-varying equation of state; and a novel adiabatic ekpyrotic phase on a ...
Khoury, Justin, Miller, Godfrey E.J.
openaire +5 more sources
Inflation in the standard cosmological model
Comptes Rendus. Physique, 2015 Abstract The inflationary paradigm is now part of the standard cosmological model as a description of its primordial phase. While its original motivation was to solve the standard problems of the hot big bang model, it was soon understood that it offers a natural theory for the origin of the large-scale structure of the universe.
Jean-Philippe Uzan, Jean-Philippe Uzan
openaire +2 more sources