Denis Frith

----- Original Message -----

From: Jay Hanson

Sent: 01/24/14 04:17 AM

Subject: [America2Point0] RE: Mathematical support for a thermodynamic origin of life - support for Salthe, Schneider and Kay - and Swenson.

On 1/22/2014 8:14 PM, hamlet.jones.esq@... wrote:

>

> This is BIG.

>

> Link to the original, not cut off, with more intelligent comments:

> https://www.simonsfoundation.org/quanta/20140122-a-new-physics-theory-of-life/

Also see:

**Understanding Complex Systems 2014, pp 163-182**

Chapter 8

Earth System Dynamics Beyond the Second Law: Maximum Power Limits, Dissipative Structures, and Planetary Interactions

Axel Kleidon, Erwin Zehe, Uwe Ehret and Ulrike Scherer**Abstract**:

Planet Earth is a thermodynamic system far from equilibrium and its functioning—obviously—obeys the second law of thermodynamics, at the detailed level of processes, but also at the planetary scale of the whole system. Here, we describe the dynamics of the Earth system as the consequence of sequences of energy conversions that are constrained by thermodynamics. We first describe the well-established Carnot limit and show how it results in a maximum power limit when interactions with the boundary conditions are being allowed for. To understand how the dynamics within a system can achieve this limit, we then explore with a simple model how different configurations of flow structures are associated with different intensities of dissipation. When the generation of power and these different configuration of flow structures are combined, one can associate the dynamics towards the maximum power limit with a fast, positive and a slow, negative feedback that compensate each other at the maximum power state. We close with a discussion of the importance of a planetary, thermodynamic view of the whole Earth system, in which thermodynamics limits the intensity of the dynamics, interactions strongly shape these limits, and the spatial organization of flow represents the means to reach these limits.

[snip]

The thermodynamic limits in this chapter were formulated in terms of maximum power limits rather than in terms of the proposed principle of Maximum Entropy Production (MaxEP). The outcomes of both, maximum power or MaxEP, are essentially indistinguishable in terms of the associated temperature gradients and heat fluxes when applied to e.g. a convective system. The maximum power limit has the advantage that it specifically describes the driving gradient and the dynamical processes involved, which should facilitate the application of this limit to Earth system processes. In comparison, the use of MaxEP is often ambiguous because it is not clear which entropy production is to be maximized and why the dynamics would be such that they result in maximization of entropy production compared to other aspects that are more directly involved in the dynamics (such as forces, energy or power). In this sense, the shift in focus to maximum power should not be seen as a contradiction to previous work on MaxEP, but rather as a continuation and sharpening of the application of thermodynamic limits to Earth system processes.

[snip]

“Genocide is as human as art or prayer.” – John Gray

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