标题： 扩展几何的真空结构 显示英文标题

标题： Vacuum structure for expanding geometry

摘要： 我们考虑了de Sitter相期间FRW度规中的引力波模，并证明态空间分裂为许多在酉等价意义下不同的正则对易关系的表示。 非酉的时间演化被描述为表示空间中的轨迹。 时间演化的生成元与熵算符有关。 热力学时间箭头被证明指向与宇宙学时间箭头相同的方向。 真空是一个两模SU(1,1)压缩态。 扩展几何、压缩和热属性之间的联系被揭示出来。 显示英文摘要

摘要： We consider gravitational wave modes in the FRW metrics in a de Sitter phase and show that the state space splits into many unitarily inequivalent representations of the canonical commutation relations. Non-unitary time evolution is described as a trajectory in the space of the representations. The generator of time evolution is related to the entropy operator. The thermodynamic arrow of time is shown to point in the same direction of the cosmological arrow of time. The vacuum is a two-mode SU(1,1) squeezed state of thermo field dynamics. The link between expanding geometry, squeezing and thermal properties is exhibited.