Essays in Science

SPACE-TIME-MATTER

This essay examines our fundamental conceptions of time, spacetime, the asymmetry of time, and the motion of a quantum mechanical particle. The concept of time has multiple meanings and these are often confused in the literature and must be distinguished if any light is to be thrown on this age-old issue. The asymmetry of time also has different meanings that depend on context—although the fundamental time asymmetry is associated with the expansion of the universe. These and related issues are discussed in both classical and quantum mechanical contexts.

(This version has been expanded and reorganized)

SPACE—TIME—MATTER V3

Essays in Science
Physics

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DOES GOD PLAY DICE? CONCEPTUAL QUANTUM PHYSICS FOR THE PERPLEXED

The late 19th century and the beginning of the 20th brought with it a revolution in the scientific understanding of the universe around us, one whose effects are still being felt around the world as it forces people to change their ideas about the universe and the place of human beings within it. Even a conceptual understanding of the early origin of the universe requires an introductory knowledge of quantum mechanics. Unfortunately, the attempt to reconcile quantum mechanics with concepts brought over from classical mechanics has led to  much confusion especially among non-physicists and students of physics.  This essay is an attempt to address some of this wide spread confusion.

DOES GOD PLAY DICE?

Essays in Science
Physics

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GROUPS: NATURE’S “INVISIBLE HAND”: AN ESSAY ON THE STANDARD MODEL

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

Errata:

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).”

Essays in Science
Physics

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The Challenge to the Enlightenment

USA Today Magazine (November 2012)

“. . . The conflict here and abroad really is between two fundamentally different and mutually exclusive world views; one based on science, reason, and observation; the other on an interpretation of Scripture that dates back to past periods of religious intolerance.”

CHALLENGE TO ENLIGHTENMENT.pdf

Biology
Essays in Science
General Interest
USA Today Magazine

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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.

NeverBornProteins-IJAB

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

Biology
Essays in Science
General Interest

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Quantum Mechanics and Motion: A Modern Perspective

Physics Essays Vol. 23, pp. 242-247 (2010)

This essay is an attempted to address, from a modern perspective, the motion of a particle. Quantum mechanically, motion consists of a series of localizations due to repeated interactions that, taken close to the limit of the continuum, yields a world-line. If a force acts on the particle, its probability distribution is accordingly modified. This must also be true for macroscopic objects, although now the description is far more complicated by the structure of matter and associated surface physics.

Quantum Mechanics and Motion-A Modern Perspective

Essays in Science
Physics

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The Demystification of Emergent Behavior

Emergent behavior that appears at a given level of organization
may be characterized as arising from an organizationally lower level in
such a way that it transcends a mere increase in the behavioral degree of
complexity. It is therefore to be distinguished from systems exhibiting
chaotic behavior, for example, which are deterministic but unpredictable
because of an exponential dependence on initial conditions. In emergent
phenomena, higher-levels of organization are not determined by lowerlevels
of organization; or, more colloquially, emergent behavior is often
said to be “greater than the sum of the parts”. The concept plays an
especially important but contentious role in the biological sciences. This
essay is intended to demystify at least some aspects of the mystery of
emergence.

(This is an updated and expanded version of the original post with some portions rewritten to enhance clarity.)

EMERGENT BEHAVIOR

Biology
Essays in Science
General Interest
Physics

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