arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 0905.0011cond-mat.stat-mechcond-mat.mes-hall
收藏

铁磁材料和临界流体标度修正的玻尔兹曼因子之外

Beyond the Boltzmann factor for corrections to scaling in ferromagnetic materials and critical fluids

Ralph V. Chamberlin, Josh V. Vermaas, George H. Wolf

摘要:

玻尔兹曼因子来自于局部涨落期间无限热浴的熵的线性变化;小系统具有显著的非线性项。我们提出的理论论据,实验数据,和蒙特卡罗模拟表明,非线性项也可能发生时,一个粒子直接与有限数量的相邻粒子相互作用,形成一个局部区域,波动独立的无限浴。一种可能的机制来自于改变粒子状态所需的净力,同时保持局部动量。这些有限大小的局部区域产生非线性波动约束,超出玻尔兹曼因子。应用于伊辛模型模拟的一个这样的波动约束降低了能量,使熵扩展,并大大提高了与铁磁材料和临界流体中测量的标度修正的一致性。

英文摘要:

The Boltzmann factor comes from the linear change in entropy of an infinite heat bath during a local fluctuation; small systems have significant nonlinear terms. We present theoretical arguments, experimental data, and Monte-Carlo simulations indicating that nonlinear terms may also occur when a particle interacts directly with a finite number of neighboring particles, forming a local region that fluctuates independent of the infinite bath. A possible mechanism comes from the net force necessary to change the state of a particle while conserving local momentum. These finite-sized local regions yield nonlinear fluctuation constraints, beyond the Boltzmann factor. One such fluctuation constraint applied to simulations of the Ising model lowers the energy, makes the entropy extensive, and greatly improves agreement with the corrections to scaling measured in ferromagnetic materials and critical fluids.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑