Local violation effects and thermalization in QCD: Views from quantum field theory and holography

Abstract

We argue that the local violation of P and CP invariance in heavy ion collisions and the universal thermal aspects observed in high energy collisions are in fact two sides of the same coin, and both are related to quantum anomalies of QCD. We argue that the low energy relations representing the quantum anomalies of QCD are saturated by coherent low dimensional vacuum configurations as observed in Monte Carlo lattice studies. The thermal spectrum and approximate universality of the temperature with no dependence on energy of colliding particles in this framework is due to the fact that the emission results from the distortion of these low dimensional vacuum sheets rather than from the colliding particles themselves. The emergence of the long-range correlations of P odd domains (a feature which is apparently required for explanation of the asymmetry observed at RHIC and LHC) is also a result of the same distortion of the QCD vacuum configurations. We formulate the corresponding physics using the effective low energy effective Lagrangian. We also formulate the same physics in terms of the dual holographic picture when low-dimensional sheets of topological charge embedded in 4d space, as observed in Monte Carlo simulations, are identified with D2 branes. Finally, we argue that study of these long range correlations in heavy ion collisions could serve as a perfect test of a proposal that the observed dark energy in present epoch is a result of a tiny deviation of the QCD vacuum energy in expanding universe from its conventional value in Minkowski spacetime.

Metastable vacuum decay and θ dependence in gauge theory. Deformed QCD as a toy model

“…The first issue we address is the question about the favoured angle, ϕ, between the two boundaries, (30) and (31). In order to find the angle we chose (arbitrarily) N = 7 and varied the angle in the range [−π, π] − 8π/7, and look at the action S 1 as a function of ϕ.…”

“…This identification would justify the effective Lagrangian approach advocated in [28,30] wherein θ( x, t) ind is treated as slow background field with correlation length much larger than any conventional QCD fluctuations, L Λ −1 QCD . It is important to emphasize that the P and CP symmetries are good symmetries of the fundamental QCD.…”

Isotropic radio background from quark nugget dark matter

“…[32] for the details. In particular, the local violation of the CP invariance observed at RHIC (Relativistic Heavy Ion Collider) [33] and LHC (Large Hadron Collider) [34] have been interpreted in [32,35,36] as an outcome of a charge separation mechanism in the presence of the induced θ ∼ 1 resulting from a collision. The difference is of course that CP odd term with θ ∼ 1 discussed in cosmology describes a theory on the horizon scale, while θ ∼ 1 in heavy ion collisions is correlated on a size of the colliding nuclei.…”

Inflaton as an auxiliary topological field in a QCD-like system

“…To be more specific, it was suggested a while ago [64][65][66][67][68] that the so-called induced theta vacua jθ ind i can be created in heavy ion collisions. This direction of studies became a very active area of research after an appropriate observational signature had been suggested [69] and theoretical computations of the effect had been put on a solid theoretical ground [70]; see also related papers [71][72][73] with specific applications to heavy ion collisions, and also review paper [74] which covers some recent theoretical development. The experimental studies at the relativistic heavy ion collider (RHIC), Brookhaven [75], and, more recently, at the LHC [76] apparently support the basic picture advocated in [69][70][71][72][73][74].…”

“…The basic idea advocated in [69][70][71][72][73][74] can be explained as follows in a few lines. Let us assume that an effective θðx; tÞ ind ≠ 0 is induced as a result of some nonequlibrium dynamics, as suggested in Refs.…”