We study the non-equilibrium dynamics of a Tonks-Girardeau gas released from parabolic trap to circle. present exact analytic solution many body and prove that, for large times in properly defined thermodynamic limit, reduced density matrix any finite subsystem converges generalized Gibbs ensemble. The equilibration mechanism is expected be same all one-dimensional systems.

We study a composite quantum quench of the energy gap and interactions in interacting \phi^4 model using self-consistent approximation. Firstly we review results for free theories where or mass leads long times to stationary behaviour with thermal characteristics. An exception this rule is 2d case zero after quench. In however find that effect our approximation simply effectively change value mass. This means on one hand also exhibits same other now true even massless case.

In the majority of analytical verifications conjecture that Generalised Gibbs Ensemble describes large time asymptotics local observables in quantum quench problems, both post-quench and pre-quench Hamiltonians are essentially noninteracting. We test this studying field correlations more general case an arbitrary Hamiltonian, while keeping one first show previously studied special a noninteracting validity is consequence Wick's theorem. then it also valid interacting but as cluster...

Complete information on the equilibrium behavior and dynamics of quantum field theory (QFT) is provided by multipoint correlation functions. However, their theoretical calculation a challenging problem, even for exactly solvable models. This has recently become an experimentally relevant due to progress in cold-atom experiments simulating QFT models directly measuring higher order correlations. Here we compute functions sine-Gordon model, prototype integrable model central interest from both...

We study the problem of a quantum quench in which initial state is ground an inhomogeneous Hamiltonian, two different models, conformal field theory and ordinary free theory, are known to exhibit thermalization finite regions homogeneous case. derive general expressions for evolution energy flow correlation functions, as well entanglement entropy Comparison results from approaches regime their common validity shows agreement up point further discussed. Unlike thermal analogue, our...

We consider a quantum quench in system of free bosons, starting from thermal initial state.As the case where is initially ground state, any finite subsystem eventually reaches stationary state with momentum-dependent effective temperature.We find that this can, some cases, even be lower than also study lattice effects and discuss more general types quenches.

We analyze quantum quenches in integrable models and particular the determination of initial state basis eigenstates post-quench hamiltonian. This leads us to consider set transformations creation annihilation operators that respect Zamolodchikov-Faddeev algebra satisfied by models. establish Bogoliubov hold only case free theories. In most general interacting theories, we identify two classes transformations. The first class induces a change S-matrix theory but not its ground state, whereas...

We consider the non-equilibrium dynamics of a gas impenetrable bosons released from harmonic trapping potential to circle. The many body is solved analytically and time dependence all physically relevant correlations described. prove that, for large times in thermodynamic limit, reduced density matrix any subsystem converges generalized Gibbs ensemble as consequence integrability model. discuss approach stationary behavior at late times. also describe time-dependence entanglement entropy...

We study inhomogeneous quantum quenches in the attractive regime of sine-Gordon model. In our protocol, system is prepared an initial state finite volume by coupling topological charge density operator to a Gaussian external field. After switching off field, subsequent time evolution governed homogeneous Hamiltonian. Varying either interaction strength model or amplitude source interesting transition observed expectation value soliton density. This affects both profile and its can be...

We investigate signal propagation in a quantum field simulator of the Klein-Gordon model realized by two strongly coupled parallel one-dimensional quasi-condensates. By measuring local phononic fields after quench, we observe correlations along sharp light-cone fronts. If atomic density is inhomogeneous, these fronts are curved. For edges, reflected at system's boundaries. extracting space-dependent variation front velocity from data, find agreement with theoretical predictions based on...

Motivated by experiments on splitting one-dimensional quasicondensates, we study the statistics of work done a quantum quench in bosonic system. We discuss general features probability distribution and focus its behavior at lowest energy threshold, which develops an edge singularity. A formal connection between this critical Casimir effect thin classical films shows that certain singularity are universal as postquench gap tends to zero. Our results quantitatively illustrated exact...

We consider the problem of determining initial state integrable quantum field theory quenches in terms post-quench eigenstates. The corresponding overlaps are a fundamental input to most exact methods treat quenches. construct and examine an infinite integral equation hierarchy based on form factor bootstrap, proposed earlier as set conditions deter- mining overlaps. Using mass interaction Sinh-Gordon concrete example, we present theoretical arguments that has squeezed coherent expected for...

We study a quantum quench of the mass and interaction in Sinh-Gordon model starting from large initial zero coupling. Our focus is on determination expansion state terms post-quench excitations. argue that energy profile involved excitations can be relevant for late time behaviour system common regularization schemes are unreliable. therefore proceed determining by first principles expanding it systematic controllable fashion basis asymptotic states. results show that, special limit...

Quench dynamics is studied for a one-dimensional system that described by the noninteracting and massless bosonic quantum field theory. The discovery of system's memory all initial correlations, which accessible local measurements at infinitely large times, suggests failure using Gaussian generalized Gibbs ensemble to describe relaxation system.

We study the equilibration properties of observables in long-range field theories after mass quench $d=1$, 2, and 3 dimensions. classify regimes where we expect or its absence different In addition, effect initial state our system. case free theories, show that whenever have equilibration, long-time limit correlations can be described by generalized Gibbs ensemble. prove all integrals motion system are nonlocal.

We study signatures of quantum chaos in $(1+1)\mathrm{D}$ field theory (QFT) models. Our analysis is based on the method Hamiltonian truncation, a numerical approach for construction low-energy spectra and eigenstates QFTs that can be considered as perturbations exactly solvable focus double sine-Gordon, also studying massive sine-Gordon ${\ensuremath{\phi}}^{4}$ model, all which are nonintegrable studied by this with sufficiently high precision from small to intermediate perturbation...

We consider a quantum quench of the trap frequency in system bosons interacting through an inverse-square potential and confined harmonic (the Calogero model). determine exactly initial state terms postquench eigenstates derive time evolution simple physical observables. Since this model possesses infinite set integrals motion that allow its exact solution, generalized Gibbs ensemble (GGE), i.e., statistical takes into account conservation all motion, can be proposed order to describe values...

We study the quench dynamics in continuous relativistic quantum field theory, more specifically locality properties of large time stationary state. After a one-dimensional integrable model, expectation values local observables are expected to relax generalized Gibbs ensemble (GGE), constructed out conserved charges model. Quenching free bosonic it has been shown that system indeed relaxes GGE described by momentum mode occupation numbers. first address question whether latter can be written...

We propose a boundary thermodynamic Bethe ansatz calculation technique to obtain the Loschmidt echo and statistics of work done when global quantum quench is performed on an integrable field theory. derive analytic expression for lowest edge probability density function find that it exhibits universal features, in sense its scaling form depends only excitations. perform numerical calculations sinh-Gordon model, deformation free boson theory, we by turning interaction develops fermionic...

Ground states ofinteracting QFTs are non-Gaussian states, i.e. their connected n-point correlation functions do not vanish for , in contrast to the free QFT case. We show that, when ground state of an interacting evolves under a massive long time (a scenario that can be realised by quantum quench), decay and all local physical observables equilibrate values given Gaussian density matrix retains memory only two-point initial function. The argument hinges upon fundamental principle cluster...

Tomonaga-Luttinger liquids (TLLs) can be used to effectively describe one-dimensional quantum many-body systems such as ultracold atoms, charges in nanowires, superconducting circuits, and gapless spin chains. Their properties are given by two parameters, the propagation velocity Luttinger parameter. Here we study inhomogeneous TLLs where these promoted functions of position demonstrate that they profoundly affect dynamics: In general, besides curving light cone, show is no longer...

One of the manifestations relativistic invariance in non-equilibrium quantum field theory is "horizon effect" a.k.a. light-cone spreading correlations: starting from an initially short-range correlated state, measurements two observers at distant space-time points are expected to remain independent until their past light-cones overlap. Surprisingly, we find that presence topological excitations correlations can develop outside horizon and indeed even between infinitely points. We demonstrate...