标题： 量子描述的波暗物质 显示英文标题

标题： A Quantum Description of Wave Dark Matter

摘要： 我们概述了一种基本的量子描述，用于玻色子暗物质（DM），其中经典波的图像在极限$m \ll 10~\textrm{eV}$中出现。 鉴于适合量子系统的特性，我们从密度矩阵开始，该矩阵包含了关于我们可以对DM进行的测量及其波动的全部信息。 根据量子光学中的基本结果，我们认为对于DM，密度矩阵最可能以相干态基下的高斯混合形式出现。 对此的偏离将导致DM可观测量中的非高斯波动，从而可以直接探测DM的量子态。 我们的受量子光学启发的方法使我们能够严格定义和解释各种通常仅以启发方式描述的量，例如相干时间或长度。 该形式化方法进一步提供了通过波粒转换的DM连续描述，我们利用它来研究不同物理尺度上的密度波动如何在两个极限之间演化，并揭示DM在波和粒子描述边界附近的独特行为。 显示英文摘要

摘要： We outline a fundamentally quantum description of bosonic dark matter (DM) from which the conventional classical-wave picture emerges in the limit $m \ll 10~\textrm{eV}$. As appropriate for a quantum system, we start from the density matrix which encodes the full information regarding the possible measurements we could make of DM and their fluctuations. Following fundamental results in quantum optics, we argue that for DM it is most likely that the density matrix takes the explicitly mixed form of a Gaussian over the basis of coherent states. Deviations from this would generate non-Gaussian fluctuations in DM observables, allowing a direct probe of the quantum state of DM. Our quantum optics inspired approach allows us to rigorously define and interpret various quantities that are often only described heuristically, such as the coherence time or length. The formalism further provides a continuous description of DM through the wave-particle transition, which we exploit to study how density fluctuations over various physical scales evolve between the two limits and to reveal the unique behavior of DM near the boundary of the wave and particle descriptions.