🔖 Statistical Mechanics, Spring 2016 (Caltech, Physics 12c with videos) by John Preskill

Statistical Mechanics, Spring 2016 (Physics 12c) by John Preskill (Caltech)
An introductory course in statistical mechanics.

Recommended textbook Thermal Physics by Charles Kittel and Herbert Kroemer

There’s also a corresponding video lecture series available on YouTube

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🔖 Thermodynamics of Prediction

Thermodynamics of Prediction by Susanne Still, David A. Sivak, Anthony J. Bell, and Gavin E. Crooks (journals.aps.org Phys. Rev. Lett. 109, 120604 (2012))
A system responding to a stochastic driving signal can be interpreted as computing, by means of its dynamics, an implicit model of the environmental variables. The system’s state retains information about past environmental fluctuations, and a fraction of this information is predictive of future ones. The remaining nonpredictive information reflects model complexity that does not improve predictive power, and thus represents the ineffectiveness of the model. We expose the fundamental equivalence between this model inefficiency and thermodynamic inefficiency, measured by dissipation. Our results hold arbitrarily far from thermodynamic equilibrium and are applicable to a wide range of systems, including biomolecular machines. They highlight a profound connection between the effective use of information and efficient thermodynamic operation: any system constructed to keep memory about its environment and to operate with maximal energetic efficiency has to be predictive.
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🔖 Statistical Physics of Adaptation

Statistical Physics of Adaptation by Nikolay Perunov, Robert A. Marsland, and Jeremy L. England (journals.aps.org Phys. Rev. X 6, 021036 (2016))
Whether by virtue of being prepared in a slowly relaxing, high-free energy initial condition, or because they are constantly dissipating energy absorbed from a strong external drive, many systems subject to thermal fluctuations are not expected to behave in the way they would at thermal equilibrium. Rather, the probability of finding such a system in a given microscopic arrangement may deviate strongly from the Boltzmann distribution, raising the question of whether thermodynamics still has anything to tell us about which arrangements are the most likely to be observed. In this work, we build on past results governing nonequilibrium thermodynamics and define a generalized Helmholtz free energy that exactly delineates the various factors that quantitatively contribute to the relative probabilities of different outcomes in far-from-equilibrium stochastic dynamics. By applying this expression to the analysis of two examples—namely, a particle hopping in an oscillating energy landscape and a population composed of two types of exponentially growing self-replicators—we illustrate a simple relationship between outcome-likelihood and dissipative history. In closing, we discuss the possible relevance of such a thermodynamic principle for our understanding of self-organization in complex systems, paying particular attention to a possible analogy to the way evolutionary adaptations emerge in living things.
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🔖 Irreversibility and Heat Generation in the Computing Process by R. Landauer

Irreversibility and Heat Generation in the Computing Process by R. Landauer (ieeexplore.ieee.org)
It is argued that computing machines inevitably involve devices which perform logical functions that do not have a single-valued inverse. This logical irreversibility is associated with physical irreversibility and requires a minimal heat generation, per machine cycle, typically of the order of kT for each irreversible function. This dissipation serves the purpose of standardizing signals and making them independent of their exact logical history. Two simple, but representative, models of bistable devices are subjected to a more detailed analysis of switching kinetics to yield the relationship between speed and energy dissipation, and to estimate the effects of errors induced by thermal fluctuations.

A classical paper in the history of entropy.

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🔖 How Life (and Death) Spring From Disorder | Quanta Magazine

How Life (and Death) Spring From Disorder by Philip Ball (Quanta Magazine)
Life was long thought to obey its own set of rules. But as simple systems show signs of lifelike behavior, scientists are arguing about whether this apparent complexity is all a consequence of thermodynamics.

This is a nice little general interest article by Philip Ball that does a relatively good job of covering several of my favorite topics (information theory, biology, complexity) for the layperson. While it stays relatively basic, it links to a handful of really great references, many of which I’ve already read, though several appear to be new to me. [1][2][3][4][5][6][7][8][9][10]

While Ball has a broad area of interests and coverage in his work, he’s certainly one of the best journalists working in this subarea of interests today. I highly recommend his work to those who find this area interesting.

References

[1]
E. Mayr, What Makes Biology Unique? Cambridge University Press, 2004.
[2]
A. Wissner-Gross and C. Freer, “Causal entropic forces.,” Phys Rev Lett, vol. 110, no. 16, p. 168702, Apr. 2013. [PubMed]
[3]
A. Barato and U. Seifert, “Thermodynamic uncertainty relation for biomolecular processes.,” Phys Rev Lett, vol. 114, no. 15, p. 158101, Apr. 2015. [PubMed]
[4]
J. Shay and W. Wright, “Hayflick, his limit, and cellular ageing.,” Nat Rev Mol Cell Biol, vol. 1, no. 1, pp. 72–6, Oct. 2000. [PubMed]
[5]
X. Dong, B. Milholland, and J. Vijg, “Evidence for a limit to human lifespan,” Nature, vol. 538, no. 7624. Springer Nature, pp. 257–259, 05-Oct-2016 [Online]. Available: http://dx.doi.org/10.1038/nature19793
[6]
H. Morowitz and E. Smith, “Energy Flow and the Organization of Life,” Santa Fe Institute, 07-Aug-2006. [Online]. Available: http://samoa.santafe.edu/media/workingpapers/06-08-029.pdf. [Accessed: 03-Feb-2017]
[7]
R. Landauer, “Irreversibility and Heat Generation in the Computing Process,” IBM Journal of Research and Development, vol. 5, no. 3. IBM, pp. 183–191, Jul-1961 [Online]. Available: http://dx.doi.org/10.1147/rd.53.0183
[8]
C. Rovelli, “Meaning = Information + Evolution,” arXiv, Nov. 2006 [Online]. Available: https://arxiv.org/abs/1611.02420
[9]
N. Perunov, R. A. Marsland, and J. L. England, “Statistical Physics of Adaptation,” Physical Review X, vol. 6, no. 2. American Physical Society (APS), 16-Jun-2016 [Online]. Available: http://dx.doi.org/10.1103/PhysRevX.6.021036 [Source]
[10]
S. Still, D. A. Sivak, A. J. Bell, and G. E. Crooks, “Thermodynamics of Prediction,” Physical Review Letters, vol. 109, no. 12. American Physical Society (APS), 19-Sep-2012 [Online]. Available: http://dx.doi.org/10.1103/PhysRevLett.109.120604 [Source]
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When Ayn Rand Collected Social Security & Medicare, After Years of Opposing Benefit Programs | Open Culture

When Ayn Rand Collected Social Security & Medicare, After Years of Opposing Benefit Programs by Josh Jones (openculture.com)

The tough part that most don’t realize or take into account is the randomness of life. In some cases one is born to wealth and privilege while others not. And even in cases of wealth and privilege one may be randomly “singled out” for disease, accidents, or other problems that may level a lifetime of working. Statistical thermodynamics and big history can tell us is that none of us are immune, all of us will die eventually, but also that we’re here because of the billions who came before us. If we’re going to beat evolution, we’ll need all the help we can get, from every single member of our society.


A robust social safety net can benefit both the individuals in a society and the society itself. Free of the fear of total impoverishment and able to meet their basic needs, people have a better opportunity to pursue long-term goals, to invent, create, and innovate. Of course, there are many who believe otherwise. And there are some, including the acolytes of Ayn Rand, who believe as Rand did: that those who rely on social systems are—to use her ugly term—“parasites,” and those who amass large amounts of private wealth are heroic supermen.
Continue reading “When Ayn Rand Collected Social Security & Medicare, After Years of Opposing Benefit Programs | Open Culture”
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