Nuclear Theory·nucl-th
7 papers—4 primary·3 cross-listed
[Submitted on 16 Sept 2014] (cross-list from hep-ph)
It is usually believed that unlike the external magnetic field which one can set directly, vorticity is a property of the flow of particles, which is indirectly controlled by external fields and initial conditions. Using the curved-space technics it is shown that the influence of the vorticity on the relativistic chiral fermions can indeed be controlled directly.
[Submitted on 26 Feb 2015] (cross-list from hep-lat)
Andrei Alexandru🇺🇸 · Ivan Horváth🇺🇸
We propose that, in SU(3) gauge theories with fundamental quarks, confinement can be inferred from spectral density of the Dirac operator. This stems from the proposition that its possible behaviors are exhausted by three distinct types (Fig.1). The monotonic cases are standard and entail confinement with valence chiral symmetry breaking (A) or the lack of both (C,C'). The bimodal (anomalous) option (B) was frequently regarded as an artifact (lattice or other) in previous studies, but we show for the first time that it persists in the continuum limit, and conclude that it informs of a non-confining phase with broken valence chiral symmetry. This generalization rests on the following. We show that bimodality in =0 theory past deconfinement temperature is stable with respect to removal of both infrared and ultraviolet cutoffs, indicating that anomalous phase is not an artifact. We demonstrate that transition to bimodality in =0 is simultaneous with the loss of confinement: anomalous phase occurs for , where is the valence chiral restoration temperature. Evidence is presented for thermal anomalous phase in =2+1 QCD at physical quark masses, whose onset too coincides with the conventional "crossover ''. We conclude that the anomalous regime is very likely a feature of nature's strong interactions. Our past studies of zero-temperature =12 theories revealed that bimodality also arises via purely light-quark effects. As a result, we expect to encounter anomalous phase on generic paths to valence chiral restoration. We predict its existence also for massless flavors () in the range , where could be quite low. Conventional arguments would associate with the onset of conformal window.
[Submitted on 5 Mar 2015] (cross-list from astro-ph.HE)
Sajad Abbar (UNM) · Joe Carlson (LANL) · Huaiyu Duan (UNM) · Sanjay Reddy (UW)
We use the quantum Monte Carlo (QMC) techniques to calculate the static structure function of a one-component ion lattice and use it to calculate the thermal conductivity of high-density solid matter expected in the neutron star crust. By making detailed comparisons with the results for the thermal conductivity obtained using standard techniques based on the one-phonon approximation (OPA) valid at low temperature, and the multi-phonon harmonic approximation expected to be valid over a wide range of temperatures, we asses the temperature regime where from QMC can be used directly to calculate . We also compare the QMC results to those obtained using classical Monte Carlo to quantitatively asses the magnitude of the quantum corrections. We find that quantum effects became relevant for the calculation of at temperature , where is the ion plasma frequency. At the quantum effects suppress by about . The comparison with the results of the OPA indicates that dynamical information beyond the static structure is needed when . These quantitative comparisons help to establish QMC as a viable technique to calculate at moderate temperatures in the range of relevance to the study of accreting neutron stars. This finding is especially important because QMC is the only viable technique so far for calculating in multi-component systems at low-temperatures.
first authorsco-authorsvia INSPIRE