标题： 空间、时间与超光速粒子 显示英文标题

标题： Space, Time and Superluminal Particles

摘要： 如果教科书中的洛伦兹不变性实际上是描述某个临界距离尺度以上物质区域的方程的属性，那么具有不同真空临界速度的多个物质区域可以共存，并且可能存在一个绝对静止参考系（真空静止参考系，可能与膨胀宇宙的局部静止参考系有关），而不会与“普通”粒子（在真空中临界速度等于c，即光速的粒子）所感受到的明显洛伦兹不变性相矛盾。 此时，时空的真实几何将不同于标准的洛伦兹不变性，庞加莱相对性原理将是一个局部的（在空间和时间上）、近似的区域性属性。 假设在真空中临界速度不同于c的粒子是超光速的，这似乎是自然的。 我们以一个旋量时空为例来说明这种情形，其中与时间变量相关的旋量的模是膨胀宇宙的大小。 从实验应用的角度出发，讨论了超光速粒子以及没有普遍相对性原理的物质的若干性质。 如果真空静止参考系接近宇宙微波背景所暗示的参考系，那么在地球上对超光速粒子的实验搜索应主要考虑实验室速度范围约为10E3 c，即使对于极高能量的超光速宇宙射线也是如此。 简要讨论了新情景的若干后果的可探测性。 显示英文摘要

摘要： If textbook Lorentz invariance is actually a property of the equations describing a sector of matter above some critical distance scale, several sectors of matter with different critical speeds in vacuum can coexist and an absolute rest frame (the vacuum rest frame, possibly related to the local rest frame of the expanding Universe) may exist without contradicting the apparent Lorentz invariance felt by "ordinary" particles (particles with critical speed in vacuum equal to c , the speed of light). The real geometry of space-time will then be different from standard Lorentz invariance, and the Poincare relativity principle will be a local (in space and time), approximate sectorial property. It seems natural to assume that particles with critical speed in vacuum different from c are superluminal. We illustrate such a scenario using as an example a spinorial space-time where the modulus of the spinor, associated to the time variable, is the size of an expanding Universe. Several properties of superluminal particles, and of matter without a universal relativity principle, are discussed in view of experimental applications. If the vacuum rest frame is close to that suggested by the cosmic microwave background, experimental searches for superluminal particles on earth should mainly contemplate a laboratory speed range around 10E3 c , even for very high energy superluminal cosmic rays. The detectability of several consequences of the new scenario is briefly discussed.