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Showing posts from October, 2012

Some elementary things about relativity and the other forces of nature

       I guess what I'm going to say here is really a non-epiphany for anyone thinking about physics for any period of time, but as I think about it I am re-inspired by relativity.  Relativity begins by insisting that the laws of nature be invariant under change in reference frame, whether inertial or not.  It doesn't matter what induces change from one reference frame to another -- gravity, electro-weak, strong -- the invariance principles must apply, else the laws of physics are inconstant, or, non-'covariant' in the Einsteinian sense.  So, while gravity stands out in that it induces an 'accelerated frame' for all masses in the area, the principle of relativity is almost a kind of theorem for all physical law, so that whatever causes a change in motion in an object also creates a context where relativity must be considered.  In this regard then, relativity is logically prior.  If acceleration didn't produce dilations and contractions, the laws of nature wo

Starting a new book

     I am going to start General Relativity by Wald.  I will be using this as an opportunity to review some topology, analysis, differential geometry etc...  This is prompted by watching some of Don Howard's wonderful lectures on Einstein.  I also have a couple of other books on black holes that might be interesting -- one has a computation of how relativity is used in GPS.  In the meantime I will wax philosophical about God knows what.      In the meantime I have been skimming a very nice book called 'Galileo's Muse', which details the artistic, literary, and philosophical context within which Galileo made his discoveries.  The book credits Dante with discovering the 3-Sphere.  Evidently a lot of people see this in the relationship between Hell and Paradise.  There are passages in the Inferno that speak of how one knows whether one is at rest or moving.  It seems as much or as little can be made of this as one wishes -- the book has not produced a document of Galileo

The Death of My Father, The Omega Point and the Explanatory Gap

     The explanatory gap can be used by those who wish to be 'idealists', in the sense that the ultimate course of the universe is actually guided by a mental goal.  If physicalism has problems, then spiritualists rejoice.  The problem with the kind of evolution Chardin and others describe is that it is goal directed.  Evolution, even mental evolution, is guided by local challenges, not universals.  Now, this can be seen as a metaphysical point, but it is actually based on what we know about adaptation.  Any universal goal is something we make up later.  Evolution is messy and undirected.      It may be that a life of increasing conscousness is the most fulfilling, but that doesn't mean that evolution is leading to that kind of life.  It is plain wishful thinking.  Besides, I'm beginning to find a peaceful but pointless life pretty enjoyable.  The existentialists admonish us that we must find our own meaning, but now I don't even know what meaning is and I don'