White Rabbit in Alice in Wonderland: I don't know what time is, but I can measure it using my cesium clock. |
- 1. Laws of physics take the same form in all inertial systems (Relativity Postulate).
- 2. The speed of light is the same in all inertial systems.
Postulate 1 stipulates that a "law of physics" must have a certain property, which is a ridiculus requirement sorting out almost all physical laws as we know them, but nevertheless does not itself express any real physics. Postulate 1 is thus empty of real physics.
Postulate 2 is according to the SI 1983 standard a definition of the length standard meter by stipulating that the speed of light is exactly 299792458 meter per second. A theoretical physicist claiming that SR is a theory about real physics, would say that Postulate 2 is both a definition/standard/convention/stiplulation and a statement about real physics in the sense that it expresses the fact that the speed of light "is" the same in all inertial systems. Both a definition/standard and physical fact. The claim is that standard works because the speed of light "is" constant, not only measured to be constant by definition. But is this reasonable?
To get perspective, let us make a comparison with the SI standard for measure of time as second defined by the
- unperturbed ground-state hyperfine transition frequency of the cesium-133 atom as 9,192,631,770 Hz or 1/second.
All observers following the SI standard will thus measure time with identical unperturbed (no exterior influence) cesium clocks. The rate of time will thus be the same for all observers (compare speed of light being the same for all observers in different inertial systems), by definition/standard.
Would it now be meaningful to claim as a Postulate saying something about real physics that the SI time standard works, because the rate of time "is the same" as some form of deep physics, which can be expressed in the following analog of Postulate 2:
- 3. The rate of time is the same in all inertial systems.
To me Postulate 3 does not make sense, because rate of time is what is measured by a cesium clock, by definition. It is meaningless to insist that the rate of time (or speed of light) "is constant" in itself, when the fact is that it is a matter of measurement standard. Speed of light and rate of time are derived entities depending on a standard and cannot be attributed having independent status as "being constant". Further, to "be constant" appears as antithesis of relativity.
This arguments indicates that Einstein's Postulate 2 does not make sense from a physical point of view. With the 1983 SI standard it is effectively only a definition void of real physics. It is a stipulation or prescription without physical truth content.
As with all standards, in particular for meter and second, the real question is to what degree different observers under different conditions following the same standard, will agree. This is discussed in the book Many-Minds Relativity. The idea is to chose the standard so that it can be shared by many. In particular, a cesium clock can be expected to show no dependence on choice of inertial system, and only very weak dependence on exterior conditions, but there may be a small dependence on e.g. temperature and gravitation like for a pendulum clock, which has nothing to do with relativity theory.
How well does the time standard work? Pretty good as evidenced by the amazing functionality and precision of the GPS system: All satellite clocks tick at the same rate synchronised with an Earth based reference clock, without being subject to any time dilation by different motion as predicted by SR. GPS works because SR is pseudo-physics, not because SR is real physics as claimed by many physicists as experimental support of SR.
How well does the time standard work? Pretty good as evidenced by the amazing functionality and precision of the GPS system: All satellite clocks tick at the same rate synchronised with an Earth based reference clock, without being subject to any time dilation by different motion as predicted by SR. GPS works because SR is pseudo-physics, not because SR is real physics as claimed by many physicists as experimental support of SR.
We are led to conclude that both Postulate 1 and 2 of SR are empty of real physics, and so SR can only by pseudo-physics, not real physics.
PS1 Note that the SI standard specifies how to "measure time" (with an unperturbed cesium clock) as an operational definition, while the question what "time is" and even more specifically what the "rate of time is", can be left out. This is a relief, since nobody has an answer.
PS2 To believe that something is true while not claiming real understanding, which is the standard attitude vs SR, is one thing. Another thing is to understand that something is fundamentally wrong, which is the non-standard view on SR, which requires more insight than just believing.
PS1 Note that the SI standard specifies how to "measure time" (with an unperturbed cesium clock) as an operational definition, while the question what "time is" and even more specifically what the "rate of time is", can be left out. This is a relief, since nobody has an answer.
PS2 To believe that something is true while not claiming real understanding, which is the standard attitude vs SR, is one thing. Another thing is to understand that something is fundamentally wrong, which is the non-standard view on SR, which requires more insight than just believing.
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