Basile, Francesco and Pelissetto, Andrea and Vicari, Ettore (2005) *The finite-temperature chiral transition in QCD with adjoint fermions.* Journal of High Energy Physics, 0502 . 044. ISSN 1029-8479

## Abstract

We study the nature of the finite-temperature chiral transition in QCD with N_f light quarks in the adjoint representation (aQCD). Renormalization-group arguments show that the transition can be continuous if a stable fixed point exists in the renormalization-group flow of the corresponding three-dimensional Phi^4 theory with a complex 2N_f x 2N_f symmetric matrix field and symmetry-breaking pattern SU(2N_f)->SO(2N_f). This issue is investigated by exploiting two three-dimensional perturbative approaches, the massless minimal-subtraction scheme without epsilon expansion and a massive scheme in which correlation functions are renormalized at zero momentum. We compute the renormalization-group functions in the two schemes to five and six loops respectively, and determine their large-order behavior. The analyses of the series show the presence of a stable three-dimensional fixed point characterized by the symmetry-breaking pattern SU(4)->SO(4). This fixed point does not appear in an epsilon-expansion analysis and therefore does not exist close to four dimensions. The finite-temperature chiral transition in two-flavor aQCD can therefore be continuous; in this case its critical behavior is determined by this new SU(4)/SO(4) universality class. One-flavor aQCD may show a more complex phase diagram with two phase transitions. One of them, if continuous, should belong to the O(3) vector universality class.

Item Type: | Article |
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Additional Information: | Imported from arXiv |

Subjects: | Area02 - Scienze fisiche > FIS/02 - Fisica teorica, modelli e metodi matematici |

Divisions: | Dipartimenti (until 2012) > DIPARTIMENTO DI FISICA " E. FERMI" |

Depositing User: | dott.ssa Sandra Faita |

Date Deposited: | 09 Apr 2015 16:04 |

Last Modified: | 09 Apr 2015 16:04 |

URI: | http://eprints.adm.unipi.it/id/eprint/1843 |

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