发表机构
Laboratoire de Physique de l’École Normale Supérieure, ENS, CNRS, Université PSL, Sorbonne Université, Université Paris Cité（巴黎高等师范学院物理实验室，ENS，法国国家科学研究中心，巴黎文理研究大学，索邦大学，巴黎西岱大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该论文在强混合多场暴胀中精确计算了原初双谱，发现新形状并揭示宇宙学对撞机信号，与Planck数据对比偏好强混合。
AI 中文摘要
利用由大质量等曲率标量扩展的暴胀涨落有效场论，在单位声速下，我们计算了在规范固定（unitary gauge）中由所有维度为四或更小的三次相互作用产生的原初双谱，其中曲率-等曲率二次混合被重求和至无量纲混合强度 $\lambda=\rho/H$ 的所有阶。将混合置于自由哈密顿量中，每个标度不变的树级双谱都简化为对独立腿核的单个 Schwinger 参数积分，而微扰论中所谓的单交换、双交换和三交换在重求和理论中成为接触图。在强混合下，我们揭示了真正新的、精确的多场双谱形状，这些形状与数据分析中使用的标准形状无相关性。压缩极限携带宇宙学对撞机信号，其频率由 dressed 质量参数 $\mu_{\rm eff}$ 设定，且在每一交换阶上都是普适的。在弱混合下，时钟系数以闭式形式获得，并精确地简化为已知的微扰单交换和双交换结果；三交换的首阶系数首次以超几何函数形式在任意质量下获得闭式表达式。在强混合下，对撞机振幅在整个 $(\lambda,\mu_{\rm eff})$ 平面上按 $e^{\pi(\lambda-2\mu_{\rm eff})/2}$ 标度。这涵盖了所有先前研究的特殊情况。六个精确形状与 Planck PR4 分箱双谱的首次对比显示了对强混合的偏好，其中宇宙学对撞机振荡侵入轻微压缩的构型。所有相互作用在整个平面上的形状随生成它们的代码一起发布，因此可以在毫秒内读取任意混合和质量下的模板。
英文摘要
Using the effective field theory of inflationary fluctuations extended by a massive isocurvature scalar, at unit sound speed, we compute the primordial bispectra generated by every cubic interaction of dimension four or less in the unitary gauge, with the curvature--isocurvature quadratic mixing resummed to all orders in the dimensionless mixing strength $λ=ρ/H$. Placing the mixing in the free Hamiltonian [...], every scale-invariant tree-level bispectrum reduces to a single Schwinger-parameter integral over independent leg kernels, and what perturbation theory calls single, double and triple exchange are contact diagrams of the resummed theory. At strong mixing we unveil genuinely new, exact multifield bispectrum shapes with no correlation to the standard shapes used in data analyses. The squeezed limit carries a cosmological collider signal with a universal frequency set by the dressed mass parameter $μ_{\rm eff}$ at every exchange order. At weak mixing the clock coefficients are obtained in closed form and reduce [...] to the known perturbative single- and double-exchange results, exactly; the triple-exchange leading coefficient is obtained in closed form at every mass, in terms of hypergeometric functions, for the first time. At strong mixing the collider amplitude scales as $e^{π(λ-2μ_{\rm eff})/2}$ over the whole $(λ,μ_{\rm eff})$ plane. This encompasses all previously studied regimes as particular cases [...]. A first confrontation of the six exact shapes with the Planck PR4 binned bispectrum shows a preference for strong mixing, where the cosmological collider oscillations invade mildly squeezed configurations [...]. The shapes of all interactions over the whole plane [...] are released with the code that produced them, so that a template at any mixing and mass can be read off in milliseconds.
Comments57 pages + appendices
