Category Archives: Philosophy of Physics

The Time Traveller’s Instantaneous Cube

I offer for consideration a very interesting dialogue from the opening of H.G. Wells’ The Time Machine (Pocket Books, 2004, page 5).  The protagonist begins:

“You know of course that a mathematical line, a line of thickness nil, has no real existence.  They taught you that?  Neither has a mathematical plane.  These things are mere abstractions.”

            “That’s all right,” said the Psychologist.

            “Nor having only length, breadth, and thickness, can a cube have a real existence.”

            “There I object,” said Filby.  “Of course a solid body may exist.  All real things —”

            “So most people think.  But wait a moment.  Can an instantaneous cube exist?”

            “Don’t follow,” said Filby.

            Can a cube that does not last for any time at all, have a real existence?”

            Filby became pensive.

            “Clearly,” the Time Traveller proceeded, “any real body must have extension in four directions, it must have Length, Breadth, Thickness, and —Duration.”

The dialogue points to what is, in my experience, a much overlooked idea: that there is an interesting constraint applied to time by the first three spatial dimensions.  When we look around, we don’t see triangles, we see things that look like triangles.  This is the sort of thinking that led Plato to the idea of universal forms and the allegory of the Cave.  The dialogue points out an interesting question: Supposing that one can obtain, say, a platonic solid, what if it exists only for an instant —that is, no duration at all?  I don’t see this question come up often in the more academic forums; maybe it does and I am just missing it.  Continue reading

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Filed under History of Science, Literature, Philosophy, Philosophy of Physics, Philosophy of Science, Physics, Pure Philosophy

A Problem with Popular Physics/Science Books: The Problem of Authorship

It should be common knowledge that it isn’t wise to accept, without air of caution, someone’s opinion on a matter as absolute fact, if that person is not an expert in the given field.  Consider popular physics, for the moment.  What field is it that a physicist (or, as will be the case in the blog post, a mathematician) is expert of?  That’s one question.  Another is: What does the composition of works in popular physics entail?  If the answer to the former is not the answer to the latter, then there is something wrong.  I believe something is. Continue reading

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Filed under Literature, Philosophy, Philosophy of Physics, Philosophy of Science, Physics, Popular Science

The Impossibility of Precisely Measuring Positions of Particles in Quantum Physics

I am not going to go too hard on him, James S. Trefil, because he is such a fine author and I enjoy his work; but I must address an error that this physicist makes in one of his books, From Atoms to Quarks: An Introduction to the Strange World of Particle Physics (1980).  (See my review of the book by clicking on this sentence.)  I have chosen Trefil’s error for discussion, because he is a fine physicist, which makes for a good mark in proving a point, namely, that physics needs philosophy of physics to mind a number of problems that are not central to advancement of the science.  These problems include the kind of conceptual one that will be mentioned —one that I hope other physicists do not err on— and conceptual problems in foundations, metaphysics, and so forth. Continue reading

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Filed under Philosophy, Philosophy of Physics, Physics, Popular Science