标题： 暴胀期间的粒子衰变：慢滚期间膨胀子量子涨落的自衰变 显示英文标题

标题： Particle decay during inflation: self-decay of inflaton quantum fluctuations during slow roll

摘要： 在膨胀期间研究了粒子衰变，通过结合动态重整化群重求和与小的 Δ 扩展来实现。 Δ 衡量了偏离标度不变功率谱的偏差并调节红外区域。 在慢滚膨胀中，Δ 是慢滚参数 ε_V、η_V 的简单函数。我们发现量子涨落可以通过膨胀过程而自衰变，这一过程在闵可夫斯基时空下是被禁止的。 我们计算了慢滚膨胀期间膨胀子量子涨落的自衰变。对于波长深入哈勃半径之内的涨落，衰变会因发射超软准直量子而增强，即超出视界量子的韧致辐射，这成为物理波长的主要衰变通道 H << k_{ph}(η) << H/(η_V - ε_V)。 短波长涨落的衰变随着物理波矢接近视界而加速。 超视界涨落以幂律 η^Γ 形式在共形时间中衰减，在曲率扰动幅度 Δ^2_R、标量光谱指数 n_s、张量与标量比值 r 和慢滚参数的条件下：Γ\simeq [32 ξ^2_V Δ^2_R] / (n_s - 1 + r/4)^2。增长模式 η^{η_V-ε_V+Γ}/η 的行为表现出异常的标度维度 Γ。 我们讨论了这些结果对标量和张量扰动以及功率谱非高斯性的意义。 最近的WMAP数据表明 Γ > 3.6 × 10^{-9}。 显示英文摘要

摘要： Particle decay during inflation is studied by implementing a dynamical renormalization group resummation combined with a small Delta expansion. Delta measures the deviation from the scale invariant power spectrum and regulates the infrared. In slow roll inflation, Delta is a simple function of the slow roll parameters epsilon_V, eta_V.We find that quantum fluctuations can self-decay as a consequence of the inflationary expansion through processes which are forbidden in Minkowski space-time. We compute the self-decay of the inflaton quantum fluctuations during slow roll inflation.For wavelengths deep inside the Hubble radius the decay is enhanced by the emission of ultrasoft collinear quanta, i.e. bremsstrahlung radiation of superhorizon quanta which becomes the leading decay channel for physical wavelengths H<<k_{ph}(eta)<<H/(eta_V-eps_V). The decay of short wavelength fluctuations hastens as the physical wave vector approaches the horizon. Superhorizon fluctuations decay with a power law eta^Gamma in conformal time where in terms of the amplitude of curvature perturbations Delta^2_R, the scalar spectral index n_s, the tensor to scalar ratio r and slow roll parameters: Gamma \simeq [32 xi^2_V Delta^2_R]/ /(n_s-1+r/4)^2.The behavior of the growing mode eta^{eta_V-epsilon_V+Gamma}/eta features an anomalous scaling dimension Gamma. We discuss the implications of these results for scalar and tensor perturbations and for non-gaussianities in the power spectrum. The recent WMAP data suggests Gamma >3.6 10^{-9}.