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    Boltzmann Equation with a Large Potential in a Periodic Box

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    The stability of the Maxwellian of the Boltzmann equation with a large amplitude external potential Φ\Phi has been an important open problem. In this paper, we resolve this problem with a large C3C3-potential in a periodic box Td\mathbb{T}^d, d3d \geq 3. We use [1] in LpLL^p-L^{\infty} framework to establish the well-posedness and the LL^{\infty}-stability of the Maxwellian μE(x,v)=exp{v22Φ(x)}\mu_E(x,v)=\exp\{-\frac{|v|^2}{2}-\Phi(x)\}

    Baryonic Response of Dense Holographic QCD

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    The response function of a homogeneous and dense hadronic system to a time-dependent (baryon) vector potential is discussed for holographic dense QCD (D4/D8 embedding) both in the confined and deconfined phases. Confined holographic QCD is an uncompressible and static baryonic insulator at large N_c and large \lambda, with a gapped vector spectrum and a massless pion. Deconfined holographic QCD is a diffusive conductor with restored chiral symmetry and a gapped transverse baryonic current. Similarly, dense D3/D7 is diffusive for any non-zero temperature at large N_c and large \lambda. At zero temperature dense D3/D7 exhibits a baryonic longitudinal visco-elastic mode with a first sound speed \lambda/\sqrt{3} and a small width due to a shear viscosity to baryon ratio \eta/n_B=\hbar/4. This mode is turned diffusive by arbitrarily small temperatures, a hallmark of holography.Comment: V2: 47 pages, 7 figures, references added, typos correcte

    Structure and correlation effects in semiconducting SrTiO₃

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    We have investigated the effects of structure change and electron correlation on SrTiO₃ single crystals using angle-resolved photoemission spectroscopy. We show that the cubic to tetragonal phase transition at 105 K is manifested by a charge transfer from in-plane (dyz and dzx) bands to out-of-plane (dxy) band, which is opposite to the theoretical predictions. Along this second-order phase transition, we find a smooth evolution of the quasiparticle strength and effective masses. The in-plane band exhibits a peak-dip-hump lineshape, indicating a high degree of correlation on a relatively large (170 meV) energy scale, which is attributed to the polaron formation
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