标题： 引力波背景中额外张量模态的振荡和宇称破坏 显示英文标题

标题： Oscillations and parity violation in gravitational wave background from extra tensor modes

摘要： 提供额外张量自由度的旁观场，在标准度规张量扰动的基础上，可以产生大量引力波（GWs）。 采用针对自旋-2场的有效场论方法，我们发现一个普遍的预测，即度规与额外张量模式之间的线性混合不可避免地在GW谱中引起振荡特征，类似于所谓的中微子振荡。 此外，自旋-2部分中的宇称破坏算符可以在产生的GW背景上留下手征特征。 我们考虑了一个具体场景，其中自旋-2场产生可观测的手征GWs，并具有特征振荡模式。 这些结果提供了对这类场景的关键特征和观测意义的模型无关描述，这些特征可以通过未来的GW探测器进行检测。 显示英文摘要

摘要： Spectator fields which provide additional tensor degrees of freedom, on top of the standard metric tensor perturbations, can produce significant amounts of gravitational waves (GWs). Employing the effective field theory approach for spin-2 fields, we find a universal prediction that linear mixing between the metric and extra tensor modes inevitably induces oscillatory features in the GW spectrum, reminiscent of the so-called neutrino oscillation. Moreover, parity-violating operators in the spin-2 sector can imprint chiral signatures on the resulting GW background. We consider a concrete scenario in which the spin-2 field generates observable chiral GWs with characteristic oscillatory patterns. These results provide a model-independent characterization of the key signatures and observational implications of such scenarios which can be detected with future GW detectors.