Entropies of the various components of the universe
arXiv:2205.05903 · doi:10.1088/1674-1137/acc2ad
Abstract
In this work, we study the entropies of photons, dust (baryonic matter), dark matter, and dark energy in the context of cosmology. When these components expand freely with the universe, we calculate the entropy and specific entropy of each component from the perspective of statistics. Under specific assumptions and conditions, the entropies of these components can satisfy the second law of thermodynamics independently. Our calculations show that the specific entropy of matter cannot be a constant during the expansion of the universe except for photons. When these components interact with the space-time background, there could exist the phenomenon of particle production (annihilation). We study the influence of the interaction on the entropies of these components, and obtain the conditions guaranteeing that the entropy of each component satisfies the second law of thermodynamics.
arXiv comment25pages, 3figures
References in corpus (41)
- Particle Dark Matter: Evidence, Candidates and Constraints
- f(R,T) gravity
- Big-Bang Nucleosynthesis and Hadronic Decay of Long-Lived Massive Particles
- f(R,L_m) gravity
- Bouncing Cosmologies: Progress and Problems
- Cosmological constant and vacuum energy: old and new ideas
- Modified gravity with arbitrary coupling between matter and geometry
- A Dying Universe: The Long Term Fate and Evolution of Astrophysical Objects
- Thermodynamic interpretation of the generalized gravity models with geometry - matter coupling
- A Larger Estimate of the Entropy of the Universe
- Gravitino Production in the Inflationary Universe and the Effects on Big-Bang Nucleosynthesis
- Gravitational induced particle production through a nonminimal curvature-matter coupling
- Turnaround in Cyclic Cosmology
- Non-minimal coupling for the gravitational and electromagnetic fields: A general system of equations
- Matter creation in a nonsingular bouncing cosmology
- Cosmological particle production, causal thermodynamics, and inflationary expansion
- Inflationary Models Driven by Adiabatic Matter Creation
- Cosmological consequences of an adiabatic matter creation process
- Perfect Fluid Dark Matter
- Does the entropy of the Universe tend to a maximum?
- Entropy evolution of universes with initial and final de Sitter eras
- Phantom behavior via cosmological creation of particles
- Information Entropy in Cosmology
- Particle Creation in Bouncing Cosmologies
- What is the entropy of the universe?
- Gravitationally induced adiabatic particle production: From Big Bang to de Sitter
- Baryogenesis in Nonminimally Coupled Theories
- Vacuum energy and cosmological evolution
- Identification of All Dark Matter as Black Holes
- Gravitational particle production in bouncing cosmologies
- Entropy of Contracting Universe in Cyclic Cosmology
- Relative information entropy and Weyl curvature of the inhomogeneous Universe
- Gravitationally influenced particle creation models and late-time cosmic acceleration
- Scalar particle production in a simple Horndeski theory
- Upper and Lower Bounds on Gravitational Entropy
- Particle Creation in Pre-Big-Bang Cosmology: theory and observational consequences
- On the Cosmological Models with Matter Creation
- Gravitationally induced particle production and its impact on structure formation
- Entropy of universe as entanglement entropy
- Entanglement Entropy and Decoupling in the Universe
- Bouncing Cosmologies