Many of the articles on this Web site are versions of the Fermi Problem described in the first section. Others are essays – some short, some long. Some are merely attempts to come to terms with basic concepts, such as the ‘size’ of the speed of light or the number ‘one trillion’. Others discuss more advanced concepts. The last few essays involve college-level physics, and might be difficult for those who have not taken at least some introductory courses. The essays discussing the gravitational field energy density and the thermodynamic four-vector are speculative and invite comments from you, the reader.
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I will hardly understand most of it, but my dendrites will be greatly massaged!