It is the purpose of this essay to take the reader from some elementary ideas about groups to the essence of the Standard Model of particle physics along a relatively straight and intuitive path. The idea is to give an Olympian view of this evolution, one that is often missing when absorbing the detailed subject matter of the Standard Model as presented in an historical approach to the subject.

Groups Natures Hidden Symmetry


p.58: First equation should read

p. 59: Line after 2nd equation from the bottom of the page should read, “This corresponds to a right-handed spinor and, for spin 1/2 is designated (1/2, 0).”

The end of the last line should read, ” . . . is designated by (0, 1/2).”

The Problem of the “Prebiotic and Never Born Proteins”

International Journal of Astrobiology / FirstView Article / October 2012, pp 1- 5
DOI: 10.1017/S1473550412000468, Published online.

International Journal of Astrobiology 12 (1): 94–98 (2013)

It has been argued that the limited set of proteins used by life as we know could not have arisen by the process of Darwinian selection from all possible proteins. This probabilistic argument has a number of implicit assumptions that may not be warranted. A variety of considerations are presented to show that the number of amino acid sequences that need to have been sampled during the evolution of proteins is far smaller than assumed by the argument.


Published version: Int.J.Astrobiology12(1)94-98(2013)

How to cite this article:
Gerald E. Marsh The problem of the ‘prebiotic and never born proteins’. International Journal of Astrobiology, Available on
CJO doi:10.1017/S1473550412000468

Deployed Nuclear Weapons and Force Structure-II

Recently, Sir Menzies Campbell wrote in the Financial Times that British nuclear doctrine should be redrawn in ways that might no longer require the Trident submarines that are currently the basis of Britain’s nuclear deterrent.  It was maintained that doing so would require abolishing the so called “Moscow criterion” that presumably drove force level requirements.

This “Nuclear Question” was the subject of the lead editorial of the Financial Times on May 19th.  In response, I submitted the following letter that was published in the 22 May 2012 edition:

Weakening Britain’s nuclear deterrent could come at a cost

Your 19 May editorial Nuclear Question lays the appropriate ground rules for the debate on the future of Britain’s deterrent: ‘First, Britain must not scrap its nuclear arsenal’, and most importantly, it ‘should only do so in multilateral negotiation with other powers. Second, it must stick to a sea-launched deterrent’  But the issue of the ‘Moscow criterion’ is a bit of a red herring.

During the cold war, Soviet ‘sophisticated air defenses’ had no capability against warheads delivered by ballistic missile and were not a factor in U.S. targeting. I doubt that this has changed.  The defense-offense balance would, however, dramatically shift if Britain eliminated its ballistic missile deterrent and relied instead on cruise missiles carried on conventional attack submarines to replace the Trident system.  A deterrent based on cruise missiles could well require higher force levels to compensate for their vulnerability.  Using cruise missiles, because of their range limitations, could also require the attack submarines carrying them to operate in areas where they would be more vulnerable. And last, but not least–and this alone should rule out their use–there is the confusion that would be introduced by any cruise missile launch: is the missile carrying a nuclear or conventional warhead? Bad idea.

While four Trident submarines would still be required for operational reasons (yes, one should always be at sea), the real issue is how many missiles must each submarine carry and how many warheads need be on each missile.  In the end, maintaining the Trident missile system may well be Britain’s most cost effective deterrent for the future.”

Dark Matter and Charged Exotic Dust

The density profiles of dark matter halos are often modeled by an approximate solution to the isothermal Lane-Emden equation with suitable boundary conditions at the origin. It is shown here that such a model corresponds to an exact solution of the Einstein-Maxwell equations for exotic charged dust. It is also shown that, because of its necessarily very small charge to mass ratio, the fact that the particles are charged does not necessarily rule out such material as a candidate for dark matter.

Dark Matter-Charged Exotic Dust

Version published in Journal of Physics and Astronomy, Volume 2, Issue 3 (2013):

J Phys & Astron-Chrged Exotic Dust

BORN SECRET: The H-Bomb, the Progressive Case and National Security

By A. DeVolpi, G.E. Marsh, T.A. Postol, and G.S. Stanford.

Born Secret looks at the widely publicized Progressive magazine case and the U.S. government’s then unprecedented attempt to prevent publication of an H-bomb design culled by a journalist from unclassified materials. The book, originally published by Pergamon Press in 1981, has long been out of print and the authors have decided to make it available to the general public and those having an interest in the Atomic Energy Act and the First Amendment. After the court proceedings ended, the authors also donated a copy of the complete unclassified in camera file to the University of Chicago Libraries.

The file is a PDF of approximately 300MB. To download, click here.


The following 6.5 MB file has been reformatted and corrected. Born Secret-Reformated with corrections-updates

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