Title: Analytic Prediction of Baryonic Effects from the EFT of Large Scale Structures Show Chinese title

Title: 大尺度结构有效场论中的重子效应解析预测

Abstract: The large scale structures of the universe will likely be the next leading source of cosmological information. It is therefore crucial to understand their behavior. The Effective Field Theory of Large Scale Structures provides a consistent way to perturbatively predict the clustering of dark matter at large distances. The fact that baryons move distances comparable to dark matter allows us to infer that baryons at large distances can be described in a similar formalism: the backreaction of short-distance non-linearities and of star-formation physics at long distances can be encapsulated in an effective stress tensor, characterized by a few parameters. The functional form of baryonic effects can therefore be predicted. In the power spectrum the leading contribution goes as $\propto k^2 P(k)$, with $P(k)$ being the linear power spectrum and with the numerical prefactor depending on the details of the star-formation physics. We also perform the resummation of the contribution of the long-wavelength displacements, allowing us to consistently predict the effect of the relative motion of baryons and dark matter. We compare our predictions with simulations that contain several implementations of baryonic physics, finding percent agreement up to relatively high wavenumbers such as $k\simeq 0.3\,h\, Mpc^{-1}$ or $k\simeq 0.6\, h\, Mpc^{-1}$, depending on the order of the calculation. Our results open a novel way to understand baryonic effects analytically, as well as to interface with simulations. Show Chinese abstract

Abstract: 宇宙的大尺度结构很可能是下一个主要的宇宙学信息来源。 因此，理解它们的行为至关重要。 大尺度结构的有效场论提供了一种一致的方式来微扰地预测大距离处暗物质的聚类。 重子运动的距离与暗物质相当这一事实使我们能够推断出，在大距离上重子可以用类似的公式描述：短距离非线性效应和长距离恒星形成物理的反冲效应可以通过一个有效应力张量来概括，该张量由几个参数表征。 因此可以预测重子效应的功能形式。 在功率谱中，主要贡献随 $\propto k^2 P(k)$ 增长，其中 $P(k)$ 是线性功率谱，数值前因子取决于恒星形成物理的细节。 我们还对长波位移的贡献进行了重新求和，从而能够一致地预测重子和暗物质相对运动的影响。 我们将我们的预测与包含多种重子物理实现的模拟进行比较，发现百分比的一致性可达相对较高的波数，例如 $k\simeq 0.3\,h\, Mpc^{-1}$ 或 $k\simeq 0.6\, h\, Mpc^{-1}$，这取决于计算的阶数。 我们的结果开辟了理解重子效应的新途径，同时也能够与模拟接口。