Compressible Navier-Stokes equations without heat conduction in Lp-framework

In this paper, we mainly consider global well-posedness and long time behavior of compressible Navier-Stokes equations without heat conduction in $L^p$-framework. This is a generalization of Peng and Zhai \cite{peng}(SIMA, 55(2023), no.2, 1439-1463), where they obtained the corresponding result in $L^2$-framework. Based on the key observation that we can release the regularity of non-dissipative entropy $S$ in high frequency in \cite{peng}, we ultimately achieve the desired $L^p$ estimate in the high frequency via complicated calculations on the nonlinear terms. In addition, we get the $L^p$-decay rate of the solution.Comment: arXiv admin note: text overlap with arXiv:2308.1638

Two approximations to the bound states of Dirac-Hulthen problem

The bound state (energy spectrum and two-spinor wave functions) solutions of the Dirac equation with the Hulthen potential for all angular momenta based on the spin and pseudospin symmetry are obtained. The parametric generalization of the Nikiforov-Uvarov method is used in the calculations. The orbital dependency (spin-orbit and pseudospin-orbit dependent coupling too singular 1/r^{2}) of the Dirac equation are included to the solution by introducing a more accurate approximation scheme to deal with the centrifugal (pseudo-centrifugal) term. The approximation is also made for the less singular 1/r orbital term in the Dirac equation for a wider energy spectrum. The nonrelativistic limits are also obtained on mapping of parameters.Comment: 29 pages, 7 figures. arXiv admin note: text overlap with arXiv:hep-th/050320

A simple proof of the characterization of functions of low Aviles Giga energy on a ball via regularity

The Aviles Giga functional is a well known second order functional that forms a model for blistering and in a certain regime liquid crystals, a related functional models thin magnetized films. Given Lipschitz domain $\Omega\subset R^2$ the functional is $I_{\epsilon}(u)=1/2\int_{\Omega} \epsilon^{-1}|1-|Du|^2|^2+\epsilon|D^2 u|^2$ where $u$ belongs to the subset of functions in $W^{2,2}_{0}(\Omega)$ whose gradient (in the sense of trace) satisfies $Du(x)\cdot \eta_x=1$ where $\eta_x$ is the inward pointing unit normal to $\partial \Omega$ at $x$. In Jabin, Otto, Perthame characterized a class of functions which includes all limits of sequences $u_n\in W^{2,2}_0(\Omega)$ with $I_{\epsilon_n}(u_n)\to 0$ as $\epsilon_n\to 0$. A corollary to their work is that if there exists such a sequence $(u_n)$ for a bounded domain $\Omega$, then $\Omega$ must be a ball and (up to change of sign) $u:=\lim_{n\to \infty} u_n =\mathrm{dist}(\cdot,\partial\Omega)$. Recently we provided a quantitative generalization of this corollary over the space of convex domains using `compensated compactness' inspired calculations originating from the proof of coercivity of $I_{\epsilon}$ by DeSimone, Muller, Kohn, Otto. In this note we use methods of regularity theory and ODE to provide a sharper estimate and a much simpler proof for the case where $\Omega=B_1(0)$ without the requiring the trace condition on $Du$.Comment: 16 pages, 1 figur

Microscopic Origin of Criticality at Macroscale in QCD Chiral Phase Transition

We reveal that the criticality of the chiral phase transition in QCD at the macroscale arises from the microscopic energy levels of its fundamental constituents, the quarks. We establish a novel relation between cumulants of the chiral order parameter (i.e., chiral condensate) and correlations among the energy levels of quarks (i.e., eigenspectra of the massless Dirac operator), which naturally leads to a generalization of the Banks-Casher relation. Based on this novel relation and through (2+1)-flavor lattice QCD calculations using the HISQ action with varying light quark masses in the vicinity of the chiral phase transition, we demonstrate that the correlations among the infrared part of the Dirac eigenspectra exhibit same universal scaling behaviors as expected of the cumulants of the chiral condensate. We find that these universal scaling behaviors extend up to the physical values of the up and down quark masses.Comment: 4 pages, 2 figures, talk presented at the 30th International Conference on Ultra-relativistic Nucleus-Nucleus Collisions (Quark Matter 2023), September 3-9, 2023, Houston, Texas, USA. arXiv admin note: text overlap with arXiv:2401.1026

New perturbation theory representation of the conformal symmetry breaking effects in gauge quantum field theory models

We propose a hypothesis on the detailed structure for the representation of the conformal symmetry breaking term in the basic Crewther relation generalized in the perturbation theory framework in QCD renormalized in the ${\rm \bar{MS}}$ scheme. We establish the validity of this representation in the $O(\alpha_s^4)$ approximation. Using the variant of the generalized Crewther relation formulated here allows finding relations between specific contributions to the QCD perturbation series coefficients for the flavor nonsinglet part of the Adler function $D^{ns}_A$ for the electron-positron annihilation in hadrons and to the perturbation series coefficients for the Bjorken sum rule $S_\text{Bjp}$ for the polarized deep-inelastic lepton-nucleon scattering. We find new relations between the $\alpha_s^4$ coefficients of $D^{ns}_A$ and $S_\text{Bjp}$. Satisfaction of one of them serves as an additional theoretical verification of the recent computer analytic calculations of the terms of order $\alpha_s^4$ in the expressions for these two quantities.Comment: 12 pages, Title modified, abstract modified, improved and extended variant of the talks, presented at Int. Seminar "Quarks-2010" (6-12 June, 2010, Kolomna) and Int. Workshop Hadron Structure and QCD: From Low to High Energies (5-9 July 2010, Gatchina