A different approach to introducing statistical mechanics
A different approach to introducing statistical mechanics
复制标题
引入统计力学的不同方法
DOI:
10.1119/1.18490
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发表时间:
2015
影响因子:
0.9
通讯作者:
D. V. Schroeder
中科院分区:
文献类型:
--
作者:
T. Moore;D. V. Schroeder
The basic notions of statistical mechanics (microstates, multiplicities) are quite simple, but understanding how the second law arises from these ideas requires working with cumbersomely large numbers. To avoid getting bogged down in mathematics, one can compute multiplicities numerically for a simple model system such as an Einstein solid—a collection of identical quantum harmonic oscillators. A computer spreadsheet program or comparable software can compute the required combinatoric functions for systems containing a few hundred oscillators and units of energy. When two such systems can exchange energy, one immediately sees that some configurations are overwhelmingly more probable than others. Graphs of entropy vs. energy for the two systems can be used to motivate the theoretical definition of temperature, T=(∂S/∂U)−1, thus bridging the gap between the classical and statistical approaches to entropy. Further spreadsheet exercises can be used to compute the heat capacity of an Einstein solid, study the ...