Related papers: Negative temperature: further extensions
This paper generalizes isomorph theory to systems that are not in thermal equilibrium. The systems are assumed to be R-simple, i.e., have a potential energy that as a function of all particle coordinates $\textbf{R}$ obeys the…
Physical scenarios that require a relativistic treatment are ubiquitous in nature, ranging from cosmological objects to charge carriers in Dirac materials. Interestingly all of these situations have in common that the systems typically…
A common feature in the thermodynamic analysis of homogeneous and isotropic world models is the assumption that the temperature of the fluids inside the cosmic horizon (including dark energy) coincides with the temperature of the latter,…
In equilibrium statistical mechanics or thermodynamics formalism one of the main objectives is to describe the behavior of families of equilibrium measures for a potential parametrized by the inverse temperature $\beta$. Here we consider…
We discuss the thermodynamic properties of the Friedmann-Robertson-Walker universe with dark energy fluids labelled by $\omega=p/\rho<-1/3$. Using the integrability condition, we show that the phantom phase of $w<-1$ can still be…
Long-lived sterile neutrinos can play the role of dark matter. We consider the possibility that such neutrinos form a thermal bath with a singlet scalar, while not being in thermal equilibrium with the Standard Model fields. Eventually, the…
This pedagogical comment highlights three misconceptions concerning the usefulness of the concept of negative temperature; being derived from the usual, often termed Boltzmann, definition of entropy. First, both the Boltzmann and Gibbs…
We investigate the equilibration and thermalization properties of quantum systems interacting with a finite dimensional environment. By exploiting the concept of time averaged states, we introduce a completely positive map which allows to…
Complete positivity is a ubiquitous assumption in the study of quantum systems interacting with the environment, despite repeated efforts to point out that the assumption is not empirically justified. It will be shown that Hamiltonian…
Negative states are an intrinsic property of relativistic quantum theory and related to anti-particles in the context of the Dirac sea concept. We show that negative states can dominantly contribute to the diffraction amplitude in the…
Theory and experiment have long discussed negative thermodynamic pressure states, but their microscopic origins are unclear. I address this problem within the framework of quantum thermodynamics. I show that the pressure exerted on the…
We study properties of effective temperature of non-equilibrium steady states by using the anti-de Sitter spacetime/conformal field theory (AdS/CFT) correspondence. We consider non-equilibrium systems with a constant flow of current along…
The meaning of temperature in nonequilibrium thermodynamics is considered by using a forced harmonic oscillator in a heat bath, where we have two effective temperatures for the position and the momentum, respectively. We invent a concrete…
We have investigated the thermodynamical properties of dark energy. Assuming that the dark energy temperature $T\sim a^{-n}$ and considering that the volume of the Universe enveloped by the apparent horizon relates to the temperature, we…
Solid-state cooling based on i-caloric effects may be an alternative to conventional vapor-compression refrigeration systems. The adiabatic temperature change ($\Delta T_{S}$) is one of the parameters that characterize the i-caloric…
A generalization of the thermodynamic uncertainty relations is proposed. It is done by introducing of an additional term proportional to the interior energy into the standard thermodynamic uncertainty relation that leads to existence of the…
When a physical system is put in contact with a very large thermal bath, it undergoes a dissipative (i.e., an apparently irreversible) process that leads to thermal equilibrium. This dynamical process can be described fully within quantum…
This work is devoted to the thermodynamics description of a phantom scenario proposed previously by the authors. The presence of negative chemical potential is unavoidable if we allege for a well defined thermodynamics framework since the…
In this paper, a theory of dark energy is proposed that matches dark matter. The relativistic quantum mechanics equations reveal that free particles can have negative energies. We think that the negative energy is the dark energy which…
We study non-canonical relaxation in a composite cold atoms system, consisting of subsystems that possess negative microcanonical specific heat. The system exhibits pre-thermalization far away from integrability due to the appearance of a…