Our last paper “Spontaneous symmetry breaking and frustrated phases”, by Heitor Casasola, Carlos A. Hernaski, Pedro R. S. Gomes, and Paula F. Bienzobaz, Phys. Rev. E 104, 034131, has just been chosen as Editors’ Suggestion in PRE!
Author Archives: Pedro Gomes
Encontro Virtual de Teoria de Campos
O link para o Encontro Virtual de Teoria de Campos pode ser encontrado aqui. O evento será realizado nos dias 2, 3 e 4 de dezembro/2020.
How to become a good theoretical physicist
Journal Club #39
Algumas Informações e Dicas sobre Pós-Graduação em Física Teórica: As escolhas, a rotina e o que é esperado
Pedro Gomes
Quando? 01/11/2018
Onde? Sala de Multimeios – Dep. de Física
Que horas? 13:00 hrs
O Journal Club é aberto a todos os estudantes de graduação e pós graduação!
Journal Club #38
Direction and redshift drifts for general observers and their applications in cosmology
by Oton Marcori
Ph. D. Candidate
High precision astrometry now enables to measure the time drift of astrophysical observables in real time, hence providing new ways to probe different cosmological models. This article presents a general derivation of the redshift and direction drifts for general observers. It is then applied to the standard cosmological framework of a Friedmann-Lemaitre space- time including all effects at first order in the cosmological perturbations, as well as in the class of spatially anisotropic universe models of the Bianchi I family. It shows that for a general observer, the direction drift splits into a parallax and an aberration drifts and order of magnitude estimates of these two components are provided. The multipolar decomposition of the redshift and aberration drifts is also derived and shows that the observer’s peculiar velocity contributes only as a dipole whereas the anisotropic shear contributes as a quadrupole.
Quando? 19/10/2018
Onde? Sala de Multimeios – Dep. de Física
Que horas? 16:00 hrs
O Journal Club é aberto a todos os estudantes de graduação e pós graduação!
Journal Club #36
Quantum Phase Transitions in Supersymmetric Spherical Spins Model: Part II
by Ladislau Tavares
Ph. D. Candidate
In this second part of the seminar we start with a brief review of the supersymmetric spherical model. We discuss the calculation of the partition function for a generic interaction of the form $U_{\mathbf{r,r’}}=U\left(\lvert\mathbf{r-r’\lvert}\right)$. Finally, we analyze the critical behavior of the mean-field version of the model. At zero temperature it exhibits a phase transition without breaking supersymmetry and, for finite temperature a phase transition with broken supersymmetry. Concerning the susceptibility, there are two regimes in the case of finite temperature characterized by distinct critical exponents.
Quando? 15/06/2018
Onde? Sala de Multimeios – Dep. de Física
Que horas? 16:00 hrs (ou após a reunião do departamento)
O Journal Club é aberto a todos os estudantes de graduação e pós graduação!
Journal Club #35
Quantum Phase Transitions in Supersymmetric Spherical Spins Model: Part I
by Lucas Gabriel dos Santos
Ph. D. Candidate
In this first part of the seminar we start with a brief introduction of the spherical model, emphasizing its quantum version. Having developed all the context of the model, we start investigating a supersymmetric extension of the quantum spherical model from an off-shell formulation directly in the superspace. We construct a supersymmetric Lagrangian and, from the on-shell formulation, we show that by considering first neighbor interactions in the superspace, the model can present competing interaction in the bosonic felds. Finally, we develop the calculation of the partition function of the model.
Quando? 06/06/2018
Onde? Sala de Multimeios – Dep. de Física
Que horas? 16:30 hrs
O Journal Club é aberto a todos os estudantes de graduação e pós graduação!
Suspensão do Seminário
Em razão da suspensão das atividades acadêmicas, o seminário #35 de 30/05 será remarcado em uma data conveniente.
Alteração: dia do seminário
Em razão das dificuldades com os transportes, o seminário #35 de 25/05 será realizado na próxima quarta-feira, dia 30/05, no mesmo horário e local, ou seja, 16:00h, na sala de multimeios do Dep. de Física.
Journal Club #35
Quantum Phase Transitions in Supersymmetric Spherical Spins Model: Part I
by Lucas Gabriel dos Santos
Ph. D. Candidate
In this first part of the seminar we start with a brief introduction of the spherical model, emphasizing its quantum version. Having developed all the context of the model, we start investigating a supersymmetric extension of the quantum spherical model from an off-shell formulation directly in the superspace. We construct a supersymmetric Lagrangian and, from the on-shell formulation, we show that by considering first neighbor interactions in the superspace, the model can present competing interaction in the bosonic felds. Finally, we develop the calculation of the partition function of the model.
Quando? 25/05/2018
Onde? Sala de Multimeios – Dep. de Física
Que horas? 16:00 hrs
O Journal Club é aberto a todos os estudantes de graduação e pós graduação!