论文标题
通货膨胀和原始重力波期间间歇性无效条件违反
Intermittent null energy condition violations during inflation and primordial gravitational waves
论文作者
论文摘要
原始无效的能量条件（NEC）违规将在重力波背景（GWB）上烙印一个蓝色倾斜的光谱。但是，它对GWB的含义可能比预期的要丰富得多。我们提出了一种场景，在这种情况下，在使用哈勃参数$ h \ simeq h_ {inf1} $的缓慢滚动（NEC-PRESERVING）通货膨胀之后，宇宙经历了NEC侵略时期，然后以更高的$ h $（$ = H_ {INF2}} \ gg h_ fly $ h $（$ = h_ {inf2} \ gg h_ fim1} $）。所得的原始引力波谱在宇宙微波背景带上几乎是平坦的，并且在频率$ f \ sim 1/{\ rm yr yr} $处，但具有较高的振幅（与最近的纳米级结果兼容）。还强调的是，对于多阶段的通货膨胀，如果NEC违规发生间歇性发生，我们可能会在相应的频带上具有随机GWB的壁样光谱。
Primordial null energy condition (NEC) violation would imprint a blue-tilted spectrum on gravitational wave background (GWB). However, its implications on the GWB might be far richer than expected. We present a scenario, in which after a slow-roll (NEC-preserving) inflation with Hubble parameter $H\simeq H_{inf1}$, the Universe goes through an NEC-violating period and then enters subsequent slow-roll inflation with a higher $H$ ($=H_{inf2}\gg H_{inf1}$). The resulting primordial gravitational wave spectrum is nearly flat at the cosmic microwave background band, as well as at the frequency $f\sim 1/{\rm yr}$ but with higher amplitude (compatible with the recent NANOGrav result). It is also highlighted that for the multi-stage inflation if the NEC violations happened intermittently, we might have a Great Wall-like spectrum of the stochastic GWB at the corresponding frequency band.
