论文标题
通过Boss星系的四点相关函数探测平等侵犯
Probing Parity-Violation with the Four-Point Correlation Function of BOSS Galaxies
论文作者
论文摘要
早期宇宙中的奇异物理可以在晚期可观察的情况下留下可检测的痕迹。虽然在宇宙微波背景的$ b $模型中可以观察到矢量和张量型均衡侵入性，但仅在四点相关函数（4PCF）及以后才能看到标量型签名。这项工作对Boss CMASS样本的4PCF进行了盲目测试，考虑到$ [20,160] H^{ - 1} \ Mathrm {MPC} $的星系间隔。 Parity-ODD 4PCF不包含标准$λ$ CDM物理学的贡献，并且可以使用最近开发的估计器进行有效测量。使用非参数等级测试（将BOSS 4PCF与现实模拟的boss 4PCF进行比较）和压缩$χ^2 $分析，对数据进行分析，前者避免假设高斯可能性。这些发现了类似的结果，等级测试给出了$ 99.6 \％$（$2.9σ$）的检测概率。这为宇宙学或系统学提供了平等侵犯的重要证据。我们进行了许多系统的测试：尽管这些测试并未揭示任何观察伪影，但我们不能排除我们的检测是由未忠实代表Boss数据统计属性的模拟引起的可能性。我们的测量值可用于限制平等侵犯的物理模型。举例来说，我们考虑了Adflaton和A $ U（1）$ GAUGE字段之间的耦合，并在后者的能量密度上放置边界，这比先前报道的高几个数量级。即将进行的探针（例如DESI和Euclid）将揭示我们对平等竞选的检测是否是由于新物理学引起的，并加强了各种模型的界限。
Parity-violating physics in the early Universe can leave detectable traces in late-time observables. Whilst vector- and tensor-type parity-violation can be observed in the $B$-modes of the cosmic microwave background, scalar-type signatures are visible only in the four-point correlation function (4PCF) and beyond. This work presents a blind test for parity-violation in the 4PCF of the BOSS CMASS sample, considering galaxy separations in the range $[20,160]h^{-1}\mathrm{Mpc}$. The parity-odd 4PCF contains no contributions from standard $Λ$CDM physics and can be efficiently measured using recently developed estimators. Data are analyzed using both a non-parametric rank test (comparing the BOSS 4PCFs to those of realistic simulations) and a compressed $χ^2$ analysis, with the former avoiding the assumption of a Gaussian likelihood. These find similar results, with the rank test giving a detection probability of $99.6\%$ ($2.9σ$). This provides significant evidence for parity-violation, either from cosmological sources or systematics. We perform a number of systematic tests: although these do not reveal any observational artefacts, we cannot exclude the possibility that our detection is caused by the simulations not faithfully representing the statistical properties of the BOSS data. Our measurements can be used to constrain physical models of parity-violation. As an example, we consider a coupling between the inflaton and a $U(1)$ gauge field and place bounds on the latter's energy density, which are several orders of magnitude stronger than those previously reported. Upcoming probes such as DESI and Euclid will reveal whether our detection of parity-violation is due to new physics, and strengthen the bounds on a variety of models.
