Related papers: FPU phenomenon for generic initial data
Phase transitions occur when a macroscopic number of local degrees of freedom coherently change their behavior. In ground states of quantum many-body systems, phase transitions due to quantum fluctuations are observed as non-analytic…
A Hamiltonian model living in a bounded phase space and with long-range interactions is studied. It is shown, by analytical computations, that there exists an energy interval in which the microcanonical entropy is a decreasing convex…
We study the original $\alpha$-Fermi-Pasta-Ulam (FPU) system with $N=16,32$ and $64$ masses connected by a nonlinear quadratic spring. Our approach is based on resonant wave-wave interaction theory, i.e. we assume that, in the weakly…
A mean-field plus pairing model for atomic nuclei in the Fe region was studied using a finite-temperature quantum Monte-Carlo method. We present results for thermodynamical quantities such as the internal energy and the specific heat. These…
The properties of a dilute granular gas in the homogeneous cooling state are mapped to those of a stationary state by means of a change in the time scale that does not involve any internal property of the system. The new representation is…
Recent variational studies have demonstrated that the strongly correlated ground states of the fractional quantum Hall (FQH) effect can be captured using machine learning approaches starting from no prior knowledge of the underlying…
A generation of neutrino experiments have established that neutrinos mix and probably have mass. The mixing phenomenon points to processes beyond those of the Standard Model, possibly at the Grand Unification energy scale. A extensive…
We discuss what the presently collected data tell us about the mechanism of multifragmentation by comparing the results of two different models, which assume or show an opposite reaction scenario, with the recent high statistics $4\pi$…
We discuss the interplay between a slow continuous drift of temperature, which induces continuous phase separation, and the non-linear diffusion term in the $\phi^4$-model for phase separation of a binary mixture. This leads to a bound for…
One-dimensional model of a system where first-order phase transition occurs is examined in the present paper. It is shown that basic properties of the phenomenon, such as a well defined temperature of transition, are caused both by…
Correlation effects in in the fluctuation of the number of particles in the process of energy branching by sequential impact ionizations are studied using an exactly soluble model of random parking on a line. The Fano factor F calculated in…
A new chapter is opening in the theory of core-collapse supernovae and neutron star mergers as simulations of these events begin to incorporate fast flavor conversion (FFC) and other forms of neutrino flavor mixing. Using numerical…
The physical pictures of the electron pairing structure and pairing mechanisms in superconductors are reviewed. An initial idea for a new physical picture of the origin and nature of the pairing is proposed. The idea is based on the…
Background properties in experimental particle physics are typically estimated using control samples corresponding to large numbers of events. This can provide precise knowledge of average background distributions, but typically does not…
Coupled models of quintessence are usually introduced for avoiding or mitigating the parameter fine-tuning problem. At the same time, the coupled models should avoid the fine-tuning problem related to the initial conditions as quintessence…
We analyze a microscopic RNA model, which includes two widely used models as limiting cases, namely it contains terms for bond as well as for stacking energies. We numerically investigate possible changes in the qualitative and quantitative…
Deviations from unitarity in the three-neutrino mixing canonical picture are expected in many physics scenarios beyond the Standard Model. The mixing of new heavy neutral leptons with the three light neutrinos would in principle modify the…
We use recent astrophysical and local tests of the stability of the fine-structure constant, $\alpha$, to constrain a particular phenomenological but physically motivated class of models in which the dark energy equation of state can…
In classical superconductors an energy gap and phase coherence appear simultaneously with pairing at the transition to the superconducting state. In high-temperature superconductors, the possibility that pairing and phase coherence are…
We consider a class of models predicting new heavy neutral fermionic states, whose mixing with the light neutrinos can be naturally significant and produce observable effects below the threshold for their production. We update the indirect…