Matter creation, adiabaticity and phantom behavior

Víctor H. Cárdenas; Samuel Lepe

doi:10.1140/epjc/s10052-025-14154-5

2023 Impact factor 4.2

Particles and Fields

Open Access

Eur. Phys. J. C (2025) 85: 411
https://doi.org/10.1140/epjc/s10052-025-14154-5

Regular Article - Theoretical Physics

Matter creation, adiabaticity and phantom behavior

Víctor H. Cárdenas¹^a and Samuel Lepe²

¹ Instituto de Fisica y Astronomia, Facultad de Ciencias, Universidad de Valparaíso, Gran Bretaãa 1111, Valparaiso, Chile
² Instituto de Física, Facultad de Ciencias, Pontificia Universidad Católica de Valparaiso, Avenida Brasil 2950, Valparaiso, Chile

^a victor.cardenas@uv.cl

Received: 26 February 2025
Accepted: 1 April 2025
Published online: 12 April 2025

Abstract

We present a novel cosmological framework that unifies matter creation dynamics with thermodynamic principles. Starting with a single-component fluid characterized by a constant equation of state parameter, $ω$ $\omega$ , we introduce a generalized second law of thermodynamics by considering the entropy associated with the cosmic horizon. Imposing an adiabatic expansion condition uniquely determines the particle creation rate, $Γ$ $\Gamma$ , a feature unprecedented in previous matter creation models. This mechanism yields a cosmology featuring phantom-like expansion while relying solely on a single constituent, which can be either a quintessence-like fluid or a non-exotic, non-relativistic dark matter component. Remarkably, this framework avoids the need to introduce an exotic negative pressure component while providing a consistent explanation for the accelerated expansion of the universe. Our results open new pathways for understanding the interplay between horizon thermodynamics, particle creation, and cosmic evolution, offering fresh insights into the nature of dark energy and its potential thermodynamic origins.

© The Author(s) 2025

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.