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pro vyhledávání: '"Komatsu, Nobuyoshi"'
Autor:
Komatsu, Nobuyoshi
To clarify a holographic modified thermodynamic relation, the present study applies a general formulation for cosmological equations in a flat FLRW universe to the first law of thermodynamics, using the Bekenstein-Hawking entropy $S_{\rm{BH}}$ and a
Externí odkaz:
http://arxiv.org/abs/2408.11279
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 109, 023505 (2024)
A cosmological model based on holographic scenarios is formulated in a flat Friedmann-Robertson-Walker universe. To formulate this model, the cosmological horizon is assumed to have a general entropy and a general temperature (including Bekenstein-Ha
Externí odkaz:
http://arxiv.org/abs/2309.16315
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 108, 083515 (2023)
The horizon of a flat Friedmann--Robertson--Walker (FRW) universe is considered to be dynamic when the Hubble parameter $H$ and the Hubble radius $r_{H}$ vary with time, unlike for de Sitter universes. To clarify the thermodynamics on a dynamic horiz
Externí odkaz:
http://arxiv.org/abs/2306.11285
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Eur. Phys. J. C 83, 690 (2023)
Horizon thermodynamics is expected to be related to the effective energy based on the energy density calculated from the Friedmann equation for a Friedmann--Robertson--Walker (FRW) universe. In the present study, the effective energy and thermostatis
Externí odkaz:
http://arxiv.org/abs/2212.05822
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 105, 043534 (2022)
Our Universe is expected to finally approach a de Sitter universe whose horizon is considered to be in thermal equilibrium. In the present article, both the energy stored on the horizon and its thermodynamic fluctuations are examined through the holo
Externí odkaz:
http://arxiv.org/abs/2112.06359
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 103, 023534 (2021)
Density perturbations related to structure formations are expected to be different in dissipative and non-dissipative universes, even if the background evolution of the two universes is the same. To clarify the difference between the two universes, f
Externí odkaz:
http://arxiv.org/abs/2011.06276
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 102, 063512 (2020)
Cosmological adiabatic particle creation results in the generation of irreversible entropy. The evolution of this entropy is examined in a flat Friedmann--Robertson--Walker universe at late times, using a dissipative model with a power-law term (prop
Externí odkaz:
http://arxiv.org/abs/2006.09650
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 100, 123545 (2019)
Thermodynamics on the horizon of a flat universe at late times is studied in holographic cosmological models that assume an associated entropy on the horizon. In such models, a $\Lambda(t)$ model similar to a time-varying $\Lambda(t)$ cosmology is fa
Externí odkaz:
http://arxiv.org/abs/1911.08306
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 99, 043523 (2019)
The holographic principle can lead to cosmological scenarios, i.e., holographic equipartition models. In this model, an extra driving term (corresponding to a time-varying cosmological term) in cosmological equations depends on an associated entropy
Externí odkaz:
http://arxiv.org/abs/1810.11138
Autor:
Komatsu, Nobuyoshi
Publikováno v:
Phys. Rev. D 96, 103507 (2017)
A power-law corrected entropy based on a quantum entanglement is considered to be a viable black-hole entropy. In this study, as an alternative to Bekenstein-Hawking entropy, a power-law corrected entropy is applied to Padmanabhan's holographic equip
Externí odkaz:
http://arxiv.org/abs/1707.09101