20.500.12556/RUL-155535 Ergodicity breaking and deviation from eigenstate thermalization in relativistic quantum field theory The validity of the ergodic hypothesis in quantum systems can be rephrased in the form of the eigenstate thermalization hypothesis (ETH), a set of statistical properties for the matrix elements of local observables in energy eigenstates, which is expected to hold in any ergodic system. We test the ETH in a nonintegrable model of relativistic quantum field theory (QFT) using the numerical method of Hamiltonian truncation in combination with analytical arguments based on Lorentz symmetry and renormalization group theory. We find that there is an infinite sequence of eigenstates with the characteristics of quantum many-body scars—that is, exceptional eigenstates with observable expectation values that lie far from thermal values—and we show that these states are one-quasiparticle states. We argue that in the thermodynamic limit the eigenstates cover the entire area between two diverging lines: the line of one-quasiparticle states, whose direction is dictated by relativistic kinematics, and the thermal average line. Our results suggest that the strong version of the ETH is violated in any relativistic QFT whose spectrum admits a quasiparticle description. statistical physics eigenstate thermalization quantum field theory statistična fizika termalizacija lastnih stanj kvantna teorija polja true false true Angleški jezik Slovenski jezik Članek v reviji 2024-04-05 10:08:58 2024-04-05 10:08:58 2024-04-06 04:17:38 0000-00-00 00:00:00 2024 0 0 Str. 021601-1-021601-7 iss. 2 Vol. 132 2024 0000-00-00 PostprintKoncna NiDoloceno NiDoloceno 0000-00-00 0000-00-00 2024-01-12 536.93 0031-9007 10.1103/PhysRevLett.132.021601 191511299 2303.15123.pdf 2303.15123.pdf 1 70414AC291FF4251362ADEABC75A2BC8 d599690d37d62d3dfca62a41667180fc70a783603ea34207d983be1b44109c78 dd5d1094-f323-11ee-afc9-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=182482 https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.132.021601 0 e38aa926-f323-11ee-afc9-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=182483 Fakulteta za matematiko in fiziko 0 0 0