暗辐射凝聚：暗QCD与哈勃常数张力
Dark Radiation Sticks Together: Dark QCD and the Hubble Tension
- Rutgers（罗格斯大学）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本文提出暗QCD模型，通过禁闭产生粘性暗辐射，在MeV能标缓解哈勃常数张力，后验H0=71.60±0.63 km/s/Mpc，并规避暗物质自相互作用约束。
中文摘要 AI 辅助
我们提出了一种暗物质模型，该暗物质带有一个新的禁闭规范群的荷，类似于标准模型的量子色动力学（QCD）。费米子部分包含重型和轻型两类类夸克费米子，它们带有暗QCD的荷。随着宇宙冷却，规范力发生禁闭，暗辐射从自由粒子转变为低质量暗π介子。这种形式的暗辐射表现为具有非零粘性的非理想流体。如果禁闭发生在MeV能标，该模型可以缓解早期与晚期哈勃参数测量之间的张力，贝叶斯后验给出$H_0 = 71.60\pm 0.63$ km/s/Mpc，并且在Planck、ACT、BBN、Pantheon+、DESI DR2和SH0ES数据之间残余张力为$3\sigma$。在晚期宇宙中，重暗物质可以规避现有的暗物质自相互作用约束，同时包含可能在未来观测中触及的丰富现象学。
英文摘要
We introduce a model of dark matter charged under a new confining gauge group akin to the Standard Model's quantum chromodynamics (QCD). The fermionic sector contains both heavy and light quark-like fermions charged under the dark QCD. As the Universe cools, the gauge force confines and dark radiation transitions from free particles to low-mass dark pions. This form of dark radiation behaves as an imperfect fluid with nonzero viscosity. If the confinement occurs at the MeV scale, the model can alleviate the tension between early- and late-time measurements of the Hubble parameter, with a Bayesian posterior of $H_0 = 71.60\pm 0.63$ km/s/Mpc and a $3σ$ residual tension across Planck, ACT, BBN, Pantheon+, DESI DR2, and SH0ES. In the late Universe, the heavy dark matter can evade existing constraints on dark matter self-interactions while containing a rich phenomenology that may be accessible in future observations.
