An increasing number of experiments at the Belle, BNL, CERN, DAΦNE and SLAC accelerators are confirming the violation of time reversal invariance (T). The violation signifies a fundamental asymmetry between the past and future and calls for a major shift in the way we think about time. Here we show that processes which violate T symmetry induce destructive interference between different paths that the universe can take through time. The interference eliminates all paths except for two that represent continuously forwards and continuously backwards time evolution. Evidence from the accelerator experiments indicates which path the universe is effectively following. This work may provide fresh insight into the long-standing problem of modeling the dynamics of T violation processes. It suggests that T violation has previously unknown, large-scale physical effects and that these effects underlie the origin of the unidirectionality of time. It may have implications for the Wheeler-DeWitt equation of canonical quantum gravity. Finally it provides a view of the quantum nature of time itself.
Dynamical resource theory of time-reversal symmetry breaking
The University of Tokyo（东京大学）；Ritsumeikan University（立命馆大学）；BKC Research Organization of Social Sciences（BKC社会科学研究机构）；Institute for Quantum Computing（量子计算研究所）；University of Waterloo（滑铁卢大学）；Perimeter Institute for Theoretical Physics（理论物理珀米特研究所）；Trans-scale Quantum Science Institute（跨尺度量子科学研究所）
Experimental Bell inequality violation without the postselection loophole
本文报道了利用能量-时间纠缠光子对Bell-Clauser-Horne-Shimony-Holt（Bell-CHSH）不等式的实验违反。该实验并非没有局部性和检测漏洞，而是第一次使用能量-时间纠缠光子违反Bell-CHSH不等式，该光子不存在由April等人描述的后选择漏洞[Phys. Rev. Lett. 83，2872（1999）]。
Partial time-reversal invariance violation in a flat, superconducting microwave cavity with the shape of a chaotic Africa billiard
我们报告的实验实现的平面，超导微波谐振器，微波台球，与部分违反时间反转（T）不变性，诱导插入铁氧体到腔体和磁化它与外部磁场垂直的谐振器平面。为了防止Meissner-Ochsenfeld效应引起的排斥，我们使用了一个腔，腔的顶板和底板由铌（一种II型超导体）制成，并将其冷却到液氦温度T LHe '4K。空洞的形状就像一个混乱的非洲台球。超导性使得精确确定共振频率的完整序列以及共振的宽度和强度成为可能，这是明确检测T不变性违反的不可或缺的先决条件，特别是当它仅部分违反时。这允许第一次从谐振频率的波动特性和强度分布中精确地指定T不变性违反的大小，这实际上敏感地依赖于它，从而提供了最合适的测量。为此，我们推导出了后者的解析表达式，这是有效的孤立共振的范围内，从没有T不变性违反完全违反。
