Abstract Parity-time (PT) symmetric lasers exploit the modulation of optical gain and loss have led to important fundamental demonstrations in non-Hermitian physics. The current theoretical analysis PT-symmetric laser physics is performed on basis adiabatic elimination medium polarization. This approximation doesn’t hold true for a more general system with strong photon-particle interactions, w...

Spontaneous symmetry breaking is a concept of fundamental importance in many areas of physics, underpinning such diverse phenomena as ferromagnetism, superconductivity, superfluidity and the Higgs mechanism. Here we demonstrate nonreciprocity and spontaneous symmetry breaking between counter-propagating light in dielectric microresonators. The symmetry breaking corresponds to a resonance freque...

URu₂Si₂ is a uranium compound that exhibits a so-called 'hidden-order' transition at ~17.5 K. However, the order parameter of this second-order transition as well as many of its microscopic properties remain unclarified despite considerable research. One of the key questions in this regard concerns the type of spontaneous symmetry breaking occurring at the transition; although rotational symmet...

We examined the basic conservation laws for diffeomorphism symmetry in context of spontaneous and local Lorentz-symmetry breaking. The were used as constraints on a generic series terms an expansion around flat background. found all such two-tensor coupling to cubic order metric tensor field fluctuations. results are presented form that can be phenomenological calculations. One key result is if...

We examine the stability properties of the ground state of two-component Bose-Einstein condensates as a function of the interspecies interactions. A stability criterion is identified from the curvature matrix of the Gross-Pitaevskii energy functional subject to the normalization conditions. By analyzing the stability signature, the characteristic features of the spontaneous spatial symmetry bre...

Using lattice QCD we study the spectrum of low-lying fermion eigenmodes. According to the Banks-Casher relation, accumulation of the low-mode is responsible for the spontaneous breaking of chiral symmetry in the QCD vacuum. On the lattice we use the overlap fermion formulation that preserves exact chiral symmetry, which is essential for low-lying mode distributions. Through a detailed compariso...