论文标题
声音的速度在密集的强相互作用中
Speed of sound in dense strong-interaction matter
论文作者
论文摘要
我们研究了在零温度和密度状态下强度相互作用的声音速度，这些速度应受到颜色诱导的间隙的影响。在（非常）高密度的情况下，我们的分析表明，声音的速度接近与下面的非相互作用夸克气体相关的渐近值，这与不考虑颜色强化差距的第一原理研究一致。然而，对于较低的密度，间隙的存在引起声音速度的提高，而不是其渐近值。重要的是，即使间隙引起的压力校正可能看起来很小，我们发现相对于化学电势的间隙衍生物仍然很大，并导致声速的密度依赖性的质量变化。考虑到低密度下声音速度的密度依赖性的约束，我们的一般考虑表明，声音速度的最大值存在。有趣的是，我们还观察到，间隙的特定特性可能与声音速度的特征性质有关，而声音速度受到观察的间接约束。
We study the speed of sound in strong-interaction matter at zero temperature and in density regimes which are expected to be governed by the presence of a color-superconducting gap. At (very) high densities, our analysis indicates that the speed of sound approaches its asymptotic value associated with the non-interacting quark gas from below, in agreement with first-principles studies which do not take the presence of a color-superconducting gap into account. Towards lower densities, however, the presence of a gap induces an increase of the speed of sound above its asymptotic value. Importantly, even if gap-induced corrections to the pressure may appear small, we find that derivatives of the gap with respect to the chemical potential can still be sizeable and lead to a qualitative change of the density dependence of the speed of sound. Taking into account constraints on the density dependence of the speed of sound at low densities, our general considerations suggest the existence of a maximum in the speed of sound. Interestingly, we also observe that specific properties of the gap can be related to characteristic properties of the speed of sound which are indirectly constrained by observations.
