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大小无更改 、 2020年10月28日 (三) 13:34
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Josef Loschmidt's criticism was provoked by the H-theorem of Boltzmann, which employed kinetic theory to explain the increase of entropy in an ideal gas from a non-equilibrium state, when the molecules of the gas are allowed to collide. In 1876, Loschmidt pointed out that if there is a motion of a system from time t<sub>0</sub> to time t<sub>1</sub> to time t<sub>2</sub> that leads to a steady decrease of H (increase of entropy) with time, then there is another allowed state of motion of the system at t<sub>1</sub>, found by reversing all the velocities, in which H must increase. This revealed that one of Boltzmann's key assumptions, molecular chaos, or, the Stosszahlansatz, that all particle velocities were completely uncorrelated, did not follow from Newtonian dynamics. One can assert that possible correlations are uninteresting, and therefore decide to ignore them; but if one does so, one has changed the conceptual system, injecting an element of time-asymmetry by that very action.
 
Josef Loschmidt's criticism was provoked by the H-theorem of Boltzmann, which employed kinetic theory to explain the increase of entropy in an ideal gas from a non-equilibrium state, when the molecules of the gas are allowed to collide. In 1876, Loschmidt pointed out that if there is a motion of a system from time t<sub>0</sub> to time t<sub>1</sub> to time t<sub>2</sub> that leads to a steady decrease of H (increase of entropy) with time, then there is another allowed state of motion of the system at t<sub>1</sub>, found by reversing all the velocities, in which H must increase. This revealed that one of Boltzmann's key assumptions, molecular chaos, or, the Stosszahlansatz, that all particle velocities were completely uncorrelated, did not follow from Newtonian dynamics. One can assert that possible correlations are uninteresting, and therefore decide to ignore them; but if one does so, one has changed the conceptual system, injecting an element of time-asymmetry by that very action.
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约瑟夫·洛斯密特Josef Loschmidt的批评是由玻尔兹曼Boltzmann的H定理引起的,该定理运用动力学理论来解释理想气体从非平衡状态,当气体分子被允许碰撞时,熵的增加。1876年,Loschmidt指出,如果一个系统从时间t<sub>0</sub>到时间t<sub>1</sub>再到时间t<sub>2</sub>有一个运动,导致H随时间的变化而稳定减少(熵的增加),那么,在t<sub>1</sub>处有另一个系统的允许运动状态,通过逆转所有的速度发现,在这个状态下H一定会增加。这揭示了玻尔兹曼的一个关键假设--分子混沌,或者说,斯托斯扎哈兰茨(Stosszahlansatz),即所有粒子速度完全不相关,并不是从牛顿动力学中得出的。人们可以断言,可能的相关性是无趣的,因此决定忽略它们;但如果这样做,就改变了概念体系,通过这一行动注入了时间不对称的因素。
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约瑟夫·洛斯密特Josef Loschmidt的批评是由玻尔兹曼Boltzmann的H定理引起的,该定理运用动力学理论来解释理想气体从非平衡状态,当气体分子被允许碰撞时,熵的增加。1876年,Loschmidt指出,如果一个系统从时间t<sub>0</sub>到时间t<sub>1</sub>再到时间t<sub>2</sub>有一个运动,导致H随时间的变化而稳定减少(熵的增加),那么,在t<sub>1</sub>处有另一个系统的允许运动状态,通过逆转所有的速度发现,在这个状态下H一定会增加。这揭示了玻尔兹曼的一个关键假设--分子混沌,或者说,斯托斯扎哈兰茨(Stosszahlansatz),即所有粒子速度完全不相关,并不是从牛顿动力学中得出的。人们可能断言,可能的相关性是无趣的,因此决定忽略它们;但如果这样做,就改变了概念体系,通过这一行动注入了时间不对称的因素。
     
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