Banca de DEFESA: PEDRO HENRIQUE MACEDO BARROS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE: PEDRO HENRIQUE MACEDO BARROS
DATA: 18/02/2022
HORA: 16:00
LOCAL: Remota
TÍTULO: Influência da simetria de difeomorfismo na classe de universalidade O(N) em qualquer ordem de loop
PALAVRAS-CHAVES: Simetria de difeomorfismo; Grupo de renormalização; Expoentes críticos.
PÁGINAS: 54
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
RESUMO:

In this work, we analytically investigated the effect of diffeomorphism
symmetry on the values of critical exponents for massive scalar field theories in
curved spacetime with λφ4interaction and O(N) symmetry. For this, we used the
vertex functions that were regularized using the dimensional regularization
method and renormalized using the minimum subtraction method. The
divergences found in the Feynman integrals were removed by adding the
vertices of counter-terms corresponding to the superficially divergent
amplitudes, characterizing the BPHZ method used in this work. During the
computation of function β and anomalous dimensions of curved spacetime, the
momentum dependent integrals and curved spacetime parameters R and Rμν
were canceled naturally. The critical exponents were first obtained up to the
order of 3-loops for one of them and up to 2-loops for the remaining ones, so it
was possible to create a theorem that generalizes these results to any loop
order. Finally, it was verified that the values of the critical exponents are
invariant to the symmetry of the diffeomorphism and consequently the
universality hypothesis remains intact regardless of the loop order. In the
conclusions, the physical interpretation of the results is presented.

MEMBROS DA BANCA:
Presidente - 1654258 - PAULO RENATO SILVA DE CARVALHO
Interno - 2643659 - IRISMAR GONCALVES DA PAZ
Externo ao Programa - 027.006.443-52 - HELDER ALEXANDER SANTOS E COSTA - UFMG
Externo ao Programa - 010.364.693-01 - OLÍMPIO PEREIRA DE SÁ NETO - UESPI