Symmetry restoration

Quantum phase transition and dynamical stability in Bose-Einstein condensates (BECs) are studied within the framework of the Cornwall-Jackiw-Tomboulis (CJT) effective action approach. The effective potential is found in the double-bubble diagram approximation. Numerical results show that in this approximation stability is strongly influenced by the chemical potential and the quantum phase transition is of second order.

8p tamynhan9 02-12-2020 19 4   Download

In this paper, the hadron-quark phase transition occurs after the chiral phase transition in the nuclear matter, that is so-called quarkyonic-like phase, in which the chiral symmetry is restored but the elementary excitation modes are nucleonic, appears just before deconfinement. In other words, there is the coexistence of hadrons and quarks as a mixed region.

11p tamynhan9 02-12-2020 13 1   Download

The equations of state of asymmetric nuclear matter (ANM) starting from the effective potential in a one-loop approximation is investigated. It was showen that chiral symmetry is restored at high nuclear density and the liquid-gas phase transition are both strongly influenced by the isospin degree of freedom.

7p tamynhan8 04-11-2020 11 1   Download

The equations of state (EoS) of asymmetric nuclear matter (ANM) starting from the effective potential in a one-loop approximation is investigated. The numerical computation showed that chiral symmetry is restored asymptotically at high nuclear density and liquid-gas phase transition in asymmetric nuclear matter is first-order.

6p tamynhan8 04-11-2020 12 1   Download

The patterns of high temperature symmetry non-restoration (SNR) and inverse symmetry braking (ISB) in the Z2 × Z2 model are investigated in detail for a specified parameters.

9p nguyenxuankha_bevandan 14-08-2020 10 1   Download

The topological Lifshitz phase transition is studied systematically within an effective model of QCD, in which the chiral symmetry, broken at zero temperature, is not restored at high temperature and/or baryon chemical potential. It is found that during phase transition the quark system undergoes a first-order transition from low density fully-gapped state to high density state with Fermi sphere which is protected by momentum-space topology. The Lifshitz phase diagram in the plane of temperature and baryon chemical potential is established.

12p thuyliebe 12-10-2018 37 1   Download

The Bose - Einstein condensation of ultra - cold Bose gases is studied by means of the Cornwall - Jackiw - Tomboulis effective potential approach in the improved double - bubble approximation which preserves the Goldstone theorem. The phase structure of Bose - Einstein condensate associating with two different types of phase transition is systematically investigated. Its main feature is that the symmetry which was broken at zero temperature gets restored at higher temperature.

9p thuyliebe 09-10-2018 21 0   Download

In this paper, we investigate the hadron-quark (HQ) phase transition occurs beyond the chiral phase transition in the nuclear matter. The results show that there exits a quarkyonic-like phase, appeared just before deconfinement, when the chiral symmetry is restored but the elementary excitation modes are still nucleonic.

12p thuyliebe 08-10-2018 22 0   Download

is symmetric. However, since the weights wj are not equal for most quadrature rules, the matrix K (equation 18.1.5) is not symmetric. The matrix eigenvalue problem is much easier for symmetric matrices, and so we should restore the symmetry if possible.

4p babyuni 17-08-2010 64 4   Download