Tetracritical behavior in strongly interacting theories

Abstract

We suggest a tetracritical fixed point to naturally occur in strongly interacting theories. As a fundamental example we analyze the temperature--quark chemical potential phase diagram of QCD with fermions in the adjoint representation of the gauge group (i.e. adjoint QCD). Here we show that such a non trivial multicritical point exists and is due to the interplay between the spontaneous breaking of a global U(1) symmetry and the center group symmetry associated to confinement. Our results demonstrate that taking confinement into account is essential for understanding the critical behavior as well as the full structure of the phase diagram of adjoint QCD. This is in contrast to ordinary QCD where the center group symmetry associated to confinement is explicitly broken when the quarks are part of the theory.Comment: RevTex, 5 figures. Final version to appear in PR

Extreme technicolor & the walking critical temperature

“…This is so since in these models the sign problem is absent. An initial study of the nonzero matter density and temperature phase diagram, highly relevant for the new dark matter candidates, has been presented in [25]. Here it was also shown that there is an intriguing relation between the matter density driven chiral phase transition and the deconfining one yielding a very rich phase diagram as function of the temperature and matter density.…”

Ultraminimal technicolor and its dark matter technicolor interacting massive particles

“…The linearly realized one will permit us to study immediately the thermal properties of the chiral phase transition relevant for electroweak baryogenesis as done for the case of Minimal Walking Technicolor [21]. Due to the interplay between multiple nearby phase transitions [60,61] we expect novel phenomena of direct interest for cosmological applications. The linearly realized Lagrangian, once extended to contain also the spin one composite spectrum, will be of immediate interest for LHC phenomenology.…”

Phase diagram of dense quark matter in QCD-like theories

“…In particular in two-color adjoint QCD deconfinement is a second-order transition and we expect a tetracritical point in the phase diagram where the deconfinement and BEC transition lines intersect [10]. In three-color adjoint QCD deconfinement is a first-order transition so that the tetracritical point is replaced with two nearby tricritical points where the second-order BEC line meets the firstorder deconfinement line [2].…”