Tuesday, July 21, 2015

verlinde The equipartition of energy, meaning of temperature, in these modes leads one to anticipate that there is also an entropy associated. When this entropy is maximized on a volume of space-time, then one retrieves the metric of space-time (i.e. the equations of gravity, e.g. GR). Since the metric satisfies the extremum in entropy on the volume, then the volume integral of the entropy can readily be converted to surface integral, via Gauss’s Theorem. This surface integral is simply an integral of the macroscopic entropy flow producing the mean entropy holographic principle.

两篇文章

1、Go with the Flow, Average Holographic Universe
如果George Smoot不是在跟我们开愚人节玩笑,那我觉得他真的滑向理论民科了,尽管他是诺奖获得者。
是否民科与你是否在一个公立或被承认的私立大学工作无关,和你思考的模式有关。当然,Smoot是一个高级民科,他不会犯低级数学错误(这是低级民科的特点),但我读不懂他文章的逻辑。
有读懂他文章的人吗?
Verlinde12天前在twitter上留了很神秘的一句话:Monday I’ll speak at the “Origin of the Universe” conference in Paris. George Smoot will talk too. My cosmo idea’s are different from his.
尽管读不懂,我们照例拷贝摘要如下。

Gravity is a macroscopic manifestation of a microscopic quantum theory of space-time, just as the theories of elasticity and hydrodynamics are the macroscopic manifestation of the underlying quantum theory of atoms. The connection of gravitation and thermodynamics is long and deep. The observation that space-time has a temperature for accelerating observers and horizons is direct evidence that there are underlying microscopic degrees of freedom. The equipartition of energy, meaning of temperature, in these modes leads one to anticipate that there is also an entropy associated. When this entropy is maximized on a volume of space-time, then one retrieves the metric of space-time (i.e. the equations of gravity, e.g. GR). Since the metric satisfies the extremum in entropy on the volume, then the volume integral of the entropy can readily be converted to surface integral, via Gauss’s Theorem. This surface integral is simply an integral of the macroscopic entropy flow producing the mean entropy holographic principle. This approach also has the added value that it naturally dispenses with the cosmological constant/vacuum energy problem in gravity except perhaps for second order quantum effects on the mean surface entropy.
2、A Note on the Thermodynamical Origin of Gravity 和上一篇文章一样,这是一篇关于引力就是熵力的文章。
这篇文章不像愚人节玩笑。但前面的对于公理化讨论在我看来没有什么物理,而后面的物理又是Verlinde工作的重新表述。
摘要:
Following Mach’s definition of mass and force in terms of space time measurement we build the conceptual structure of classical mechanics and show that it is remarkably similar to the results of Carnot and Clausius in thermodynamics. The analogy is extended to equality to derive the laws of gravity from the laws of thermodynamics.

No comments:

Post a Comment