Monday, April 14, 2014

wang01 体系达到平衡状态的充分必要条件是达到“细致平衡”——这就是细致平衡原理

http://www.phy.pku.edu.cn/~fusion/forum/download.php?id=254&sid=4e2ef25cf00012d176062c74aebc7210

细致平衡原理
H 定理和热力学第二定律的微观第一性原理证明引起物理学界的争论:既然
Boltzmann 方程具有宏观不可逆性质,那么作为其出发点的微观物理规律的可
逆性呢?

细致平衡原理告诉我们 Boltzmann 方程的微观可逆性:

f fff

 。            (2.07)
11
也就是说,如果
dt
时间段的元碰撞引起的分布函数变化
 
f ff d ddtdd xvv

()
11
c
与相同时段反元碰撞引起的分布函数变化
f ff d ddtdd

xvv

()
11
i
相等,则我们说体系处于“细致平衡”状态。而这个状态就是平衡态。即体系
达到平衡状态的充分必要条件是达到“细致平衡”——这就是细致平衡原理。


A quantum mechanical model of adaptive mutation
Johnjoe McFadden a,*, Jim Al-Khalili b
a Molecular Microbiology Group, School of Biological Sciences, Uni6ersity of Surrey, Guildford, Surrey GU2 5XH, UK
b Department of Physics, Uni6ersity of Surrey, Guildford, Surrey GU2 5XH UK
Received 10 August 1998; accepted 15 January 1999
Abstract
The principle that mutations occur randomly with respect to the direction of evolutionary change has been
challenged by the phenomenon of adaptive mutations. There is currently no entirely satisfactory theory to account for
how a cell can selectively mutate certain genes in response to environmental signals. However, spontaneous mutations
are initiated by quantum events such as the shift of a single proton (hydrogen atom) from one site to an adjacent one.
We consider here the wave function describing the quantum state of the genome as being in a coherent linear
superposition of states describing both the shifted and unshifted protons. Quantum coherence will be destroyed by the
process of decoherence in which the quantum state of the genome becomes correlated (entangled) with its surroundings.
Using a very simple model we estimate the decoherence times for protons within DNA and demonstrate that quantum
coherence may be maintained for biological time-scales. Interaction of the coherent genome wave function with
environments containing utilisable substrate will induce rapid decoherence and thereby destroy the superposition of
mutant and non-mutant states. We show that this accelerated rate of decoherence may significantly increase the rate
of production of the mutated state. © 1999 Elsevier Science Ireland Ltd. All rights reserved.

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