physics | Chris Aldrich

Bookmarked Statistical Physics of Self-Replication by Jeremy L. England (J. Chem. Phys. 139, 121923 (2013); )

Self-replication is a capacity common to every species of living thing, and simple physical intuition dictates that such a process must invariably be fueled by the production of entropy. Here, we undertake to make this intuition rigorous and quantitative by deriving a lower bound for the amount of heat that is produced during a process of self-replication in a system coupled to a thermal bath. We find that the minimum value for the physically allowed rate of heat production is determined by the growth rate, internal entropy, and durability of the replicator, and we discuss the implications of this finding for bacterial cell division, as well as for the pre-biotic emergence of self-replicating nucleic acids.
https://doi.org/10.1063/1.4818538

Syndicated copy also available on arXiv: https://arxiv.org/abs/1209.1179

Hat tip to Paul Davies in The Demon in the Machine

👓 Michael Atiyah, Mathematician in Newton’s Footsteps, Dies at 89 | New York Times

Read Michael Atiyah, Mathematician in Newton’s Footsteps, Dies at 89 (New York Times)

One of the 20th century’s leading mathematical theorists, he revealed a connection between math and physics not seen since the 17th century.

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🎧 Episode 101 A Journey of Computational Complexity with Stephen Wolfram | Human Current

Listened to Episode 101 A Journey of Computational Complexity with Stephen Wolfram by

Hayley Campbell-Gross from HumanCurrent

In this episode, Haley interviews Stephen Wolfram at the Ninth International Conference on Complex Systems. Wolfram is the creator of Mathematica, Wolfram|Alpha and the Wolfram Language; the author of A New Kind of Science; and the founder and CEO of Wolfram Research. Wolfram talks with Haley about his professional journey and reflects on almost four decades of history, from his first introduction to the field of complexity science to the 30 year anniversary of Mathematica. He shares his hopes for the evolution of complexity science as a foundational field of study. He also gives advice for complexity researchers, recommending they focus on asking simple, foundational questions.

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🔖 [1810.05095] The Statistical Physics of Real-World Networks | arXiv

Bookmarked [1810.05095] The Statistical Physics of Real-World Networks by Giulio Cimini, Tiziano Squartini, Fabio Saracco, Diego Garlaschelli, Andrea Gabrielli, Guido Caldarelli (arxiv.org)

Statistical physics is the natural framework to model complex networks. In the last twenty years, it has brought novel physical insights on a variety of emergent phenomena, such as self-organisation, scale invariance, mixed distributions and ensemble non-equivalence, which cannot be deduced from the behaviour of the individual constituents. At the same time, thanks to its deep connection with information theory, statistical physics and the principle of maximum entropy have led to the definition of null models reproducing some features of empirical networks, but otherwise as random as possible. We review here the statistical physics approach for complex networks and the null models for the various physical problems, focusing in particular on the analytic frameworks reproducing the local features of the network. We show how these models have been used to detect statistically significant and predictive structural patterns in real-world networks, as well as to reconstruct the network structure in case of incomplete information. We further survey the statistical physics frameworks that reproduce more complex, semi-local network features using Markov chain Monte Carlo sampling, and the models of generalised network structures such as multiplex networks, interacting networks and simplicial complexes.

Comments: To appear on Nature Reviews Physics. The revised accepted version will be posted 6 months after publication

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👓 Atiyah and the Fine-Structure Constant | Sean Carroll

Read Atiyah and the Fine-Structure Constant by Sean Carroll (Sean Carroll)

Sir Michael Atiyah, one of the world’s greatest living mathematicians, has proposed a derivation of α, the fine-structure constant of quantum electrodynamics. A preprint is here. The math her…

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