James Charles Phillips

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James Charles Phillips (born March 9, 1933) is an American physicist and a member of the National Academy of Science (1978). Phillips invented the exact theory of the ionicity of chemical bonding in semiconductors, as well as new theories of compacted networks (including glasses, high temperature superconductors, and proteins).

Contents

Biography

Phillips spent postdoctoral years at Univ. California (Berkeley) with Charles Kittel, and at the Cavendish Lab., Cambridge Univ., where he introduced PP ideas that were used there for decades by Volker Heine and others. He returned to the University of Chicago as a faculty member (1960-1968). There he and Marvin L. Cohen extended PP theory to calculate the fundamental optical and photoemission spectra of many semiconductors, with high precision. [1] [2] [3]

Phillips returned to full-time research at Bell Laboratories (1968-2001), where he completed his dielectric studies of semiconductor properties. In 1979 he invented a practical theory of compacted networks, known as rigidity theory, specifically applied first to network glasses, based on topological principles and Lagrangian bonding constraints [1100+ citations]. Over time this theory organized large quantities of glass data, and culminated in the discovery (1999) by Punit Boolchand of a new phase of matter – the Intermediate Phase of glasses, free of internal stress, and with a nearly reversible glass transition. This theory has been adopted at Corning, [4] where it has contributed to the invention of new specialty glasses, including Gorilla glass (used in over three billion portable devices in 2014) and others. In 2001 Phillips moved to Rutgers University, where he completed his 1987 theory of high temperature superconductors as self-organized percolative dopant networks, by displaying their high Tc systematics in a unique Pauling valence compositional plot with a symmetric cusp-like feature, entirely unlike that known for the critical temperatures Tc of any other phase transition. [5]

Next he found a way [6] to connect Per Bak’s ideas of Self-Organized Criticality to proteins, which are networks compacted into globules by hydropathic forces, by using a new hydrophobicity scale (similar in precision to his dielectric scale of ionicity) invented in Brazil using bioinformatic methods on more than 5000 structures in the Protein Data Base. [7]

Phillips has since applied his bioinformatic scaling methods to several medically important families. [8]

In 2020 Philips contributed a manuscript to the Proceedings of the National Academy of Sciences concluding that the evolution of human Dynein shows features "indicative of intelligent design". [9] An accompanying letter did not support this controversial conclusion: "Invoking intelligent design in an attempt to buttress unjustified generalizations on evolution is non sequitur writ large". [10] The work was continued to discuss the evolution of Coronavirus (CoV) from 2003 to 2019. It identified a new set of spike mutations suggested to explain the very high contagiousness of CoV2019. The theory also predicted the very high success of the Oxford vaccine, later reported in newspapers [11]

Publications

Phillips has published four books and more than 500 papers. He has patterned his work after that of Enrico Fermi and Linus Pauling; it emphasizes general new ideas in the concrete context of problem solving. One of his highlights not mentioned above is his (1994) bifurcated solution to the fractions found in stretched exponential relaxation, the oldest (~ 140 years) unsolved problem in science. This controversial topological model was confirmed in a decisive experiment by Corning, with their best glasses in specially tailored geometries (2011). His bifurcation theory also explains (2010,2012) the distributions of 600 million citations from 25 million papers (all of 20th century science), and why they changed abruptly in 1960. [12]

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Rigidity theory, or topological constraint theory, is a tool for predicting properties of complex networks based on their composition. It was introduced by James Charles Phillips in 1979 and 1981, and refined by Michael Thorpe in 1983. Inspired by the study of the stability of mechanical trusses as pioneered by James Clerk Maxwell, and by the seminal work on glass structure done by William Houlder Zachariasen, this theory reduces complex molecular networks to nodes constrained by rods, thus filtering out microscopic details that ultimately don't affect macroscopic properties. An equivalent theory was developed by P.K. Gupta A.R. Cooper in 1990, where rather than nodes representing atoms, they represented unit polytopes. An example of this would be the SiO tetrahedra in pure glassy silica. This style of analysis has applications in biology and chemistry, such as understanding adaptability in protein-protein interaction networks. Rigidity theory applied to the molecular networks arising from phenotypical expression of certain diseases may provide insights regarding their structure and function.

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References

  1. ↑ Phillips, J. C. Bonds and Bands in Semiconductors (New York:Academic:1973)
  2. ↑ Phillips, J. C. and Lucovsky G. Bonds and Bands in Semiconductors (New York:Momentum:2009)
  3. ↑ Cohen, M. L. and Chelikowsky, J. R. Electronic Structure and Optical Properties of Semiconductors (Berlin:Springer:1988)
  4. ↑ Mauro, J. C. Amer. Ceram. Soc. Bull. 90, 32 (2011)
  5. ↑ Phillips, J. C. Proc. Natl. Acad. Sci. 107,1307 (2010)
  6. ↑ Phillips, J. C. Phys. Rev. E 80, 051916 (2009)
  7. ↑ Zebende, G. and Moret, M. Phys. Rev. E 75, 011920 (2007)
  8. ↑ Phillips, J. C.Phys. A 427,277 (2015)
  9. ↑ Phillips, J. C. PNAS 117, 7799-7802 (2020)
  10. ↑ Koonin, E. V, Wolf, Y. I. and Katsnelson, M. I. PNAS 117, 19639 (2020)
  11. ↑ Phillips, J. C. arXiv2008.12168 Aug. 28, 2020
  12. ↑ Naumis, G. G. and Phillips, J. C. J. Non-Cryst. Sol. 358, 893 (2012)
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