Massive Fluctuations in Deconfining SU(2) Yang-Mills Thermodynamics

Autor: Ingolf Bischer
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Advances in High Energy Physics, Vol 2017 (2017)
Druh dokumentu: article
ISSN: 1687-7357
1687-7365
DOI: 10.1155/2017/8593678
Popis: We review how vertex constraints inherited from the thermal ground state strongly reduce the integration support of loop four-momenta associated with massive quasiparticles in bubble diagrams constituting corrections to the free thermal quasiparticle pressure. In spite of the observed increasingly suppressing effect when increasing 2-particle-irreducible (2PI) loop order, a quantitative analysis enables us to disprove the conjecture voiced in hep-th/0609033 that the loop expansion would terminate at a finite order. This reveals the necessity to investigate exact expressions of (at least some) higher-loop order diagrams. Explicit calculation shows that although the behaviour of the 2PI three-loop contribution at low temperatures displays hierarchical suppression compared to lower loop orders, its high-temperature expression instead dominates all lower orders. However, an all-loop-order resummation of a class of 2PI bubble diagrams is shown to yield an analytic continuation of the low-temperature hierarchy to all temperatures in the deconfining phase.
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