相关论文: Instanton Induced Large $N$ Phase Transitions in T…
A central object in any axionic theory is its periodic potential, which is typically generated by instantons. The goal of this paper is to understand what physically happens to the theory when we lose control of the potential's instanton…
Monte Carlo studies of $CP^{N-1}$ sigma models have shown that the structure of topological charge in these models undergoes a sharp transition at $N=N_c\approx 4$. For $N<N_c$ topological charge is dominated by small instantons, while for…
Quantum phase transitions (QPTs) in qubit systems are known to produce singularities in the entanglement, which could in turn be used to probe the QPT. Current proposals to measure the entanglement are challenging however, because of their…
Quantum-phase transitions in two layers of ultrasmall Josephson junctions, coupled capacitively with each other, are investigated. As the interlayer capacitance is increased, the system at zero temperature is found to exhibit an…
The cosmological QCD phase transition is studied in terms of the color confinement at finite temperature using the dual Higgs theory of QCD. The confinement force is largely reduced at high temperature, which leads to the swelling of…
This work investigates dynamical quantum phase transitions (DQPTs) in a one-dimensional Ising model subjected to a periodically modulated transverse field. In contrast to sudden quenches, we demonstrate that a DQPT can be induced in two…
Some old and new evidence for the existence of the string (planar random surfaces) representation of multicolour QCD are reviewed. They concern the random surface representation of the strong coupling expansion in lattice multicolour gauge…
We investigate the effects of quenched randomness on topological quantum phase transitions in strongly interacting two-dimensional systems. We focus first on transitions driven by the condensation of a subset of fractionalized…
Four-dimensional (4D) simplicial quantum gravity coupled to U(1) gauge fields has been studied using Monte-Carlo simulations. A negative string susceptibility exponent is observed beyond the phase-transition point, even if the number of…
The quark-antiquark pairing due to the four-fermion direct coupling induced by the instantons in QCD is studied in the framework of the functional integral method. The integral equations for the order parameters are derived. Several classes…
We study quantum phase transitions out of the fracton ordered phase of the $\mathbb{Z}_N$ X-cube model. These phase transitions occur when various types of sub-dimensional excitations and their composites are condensed. The condensed phases…
We consider the de Sitter cosmology deformed by the presence of a thermal bath of radiation and/or time-dependent moduli fields. Depending on the parameters, either a first or second order phase transition can occur. In the first case, an…
QCD instantons generate non-perturbative spin- and flavor- dependent forces between quarks. We review the results of a series of studies on instanton-induced correlations in hadrons. We first present some evidence for instanton-mediated…
The partition functions of QCD2 on simple surfaces admit representations in terms of exponentials of the inverse coupling, that are modular transforms of the usual character expansions. We review the construction of such a representation in…
We show that the instanton-induced inelastic processes, leading to multi-gluon production in in high-energy parton-parton scattering, are considerably enhanced over the quasi-elastic ones, by a factor of 100. The basic instanton-induced…
We consider a phase transition induced by the growth of Q-balls in a false vacuum. Such a transition could occur in the early universe in the case of broken supersymmetry with a metastable false vacuum. Small Q-balls with a negative…
Phase transitions are prevalent throughout physics, spanning thermal phenomena like water boiling to magnetic transitions in solids. They encompass cosmological phase transitions in the early universe and the transition into a quark-gluon…
Using the liquid instanton model continued into Minkowski space and modified for finite temperature, the energy momentum tensor and the surface tension for buble walls during the QCD phase transition are derived. The resulting surface…
We calculate the contribution of the instanton -- anti-instanton ($I\bar I$) pairs to the vacuum energy of QCD-like theories with $N_f$ light fermions using the saddle point method. We find a qualitative change of the behavior: for $N_f \ge…
We investigate the effect of quenched bond-disorder on the anisotropic spin-1/2 (XXZ) chain as a model for disorder induced quantum phase transitions. We find non-universal behavior of the average correlation functions for weak disorder,…