Re: Hi experts, I can't understand what proper time and coordinate time are, can you help?, thanks

Juan R. González-Álvarez wrote:
Tom Roberts wrote on Tue, 28 Oct 2008 09:06:48 -0500:
Juan R. González-Álvarez wrote:
99% of relativists (including own Einstein) confound clock rate with
time.
Well, yes. But the word "confound" is inappropriate here, as this is
really "time is defined as what a clock measures".

Time was defined and used in physics much before than 1905.

Sure. But like virtually all words of the technical vocabulary, its meaning has morphed over the years as new knowledge and understanding is gained and new theories are formulated.


Einstein strong mistake was not that he choose a specific operational definition without analyzing its advantages/disadvantages, but that he confounded that concept of time with Newtonian concept of time.

Nonsense. The concept "time" has CHANGED. And the change has been done to MINIMIZE discrepancies from older meanings, while remaining valid for new theories and understanding of the world.


Evidently, Einstein concept of time cannot reproduce all range of phenomena that Newtonian time can.

Quite the opposite. The Newtonian meaning of time (which is absolute) cannot be accurately applied to the world we inhabit -- time quite clearly elapses differently for observers in different motion [#]. The observations and understanding that underlie this have occurred in the past century or so, so it's no surprise that Newton did not know this. But there is no excuse for someone like you, living today.

[#] yes, I'm using the standard, modern meaning of "time".
And this is precisely how those observers would describe
the elapsing of time among themselves.


> [...]

Using new, untested and unverified theories, and claiming they are "current" (or even "correct") well before the mainstream of physics has accepted them, and claiming they have redefined primary terms like "time", is all rather silly. Expecting others to do so as well is outrageous.

Citing Wikipdia and your personal webpages as sources
is also rather silly. Wikipedia pages routinely get
hijacked by people whose personal agendas supersede
understanding and knowledge.



To date, EVERY experiment that does so has measured "time" with a clock, and that seems unlikely to change anytime soon. So the Einstein definition "time is what clocks measure" is PRECISELY what is needed for theory to compare to experiments. If a new theory has some sort of "invariant evolution parameter", then that is a better name for it than "time", because that sort of morphing of the meaning of "time" is NOT minimal, AND IS IN CONTRADICTION WITH HOW EXPERIMENTS DEFINE AND MEASURE "TIME".

Also: I strongly suspect that any theory with an "invariant
evolution parameter" will find that it is unobservable,
and thus completely useless as a definition of "time".


Tom Roberts
.

Relevant Pages

  • Re: Hi experts, I cant understand what proper time and coordinate time are, can you help?, thanks
    ... meaning has morphed over the years as new knowledge and understanding is ... The meaning of time has become more vague as the relativists trying to ... A clock is a device to measure time. ... *For a definition of co-inertial time, ...
    (sci.physics.relativity)
  • Re: "The Brilliance of Our Teachers"
    ... One of those instructors explained the concepts ... matter would be straightforward by now, the understanding of modern physics ... overlooking the fact that nothing is known until observation, mathematics ... the speed of a clock is affected by the mass ...
    (sci.physics.relativity)
  • Re: "The Brilliance of Our Teachers"
    ... One of those instructors explained the concepts ... matter would be straightforward by now, the understanding of modern physics ... the speed of a clock is affected by the mass ... matter would also contract by 1/2 but in reality such a clock would ...
    (sci.physics.relativity)
  • Re: coordinates and equations.
    ... Another stupid trick, Robert? ... you cannot evade the issus: a single clock cannot show ... you'll notice that I took care to explicit the meaning of variables, ... repeat that t in the first expression is not the same as t in the ...
    (sci.physics.relativity)
  • Re: coordinates and equations.
    ... Another stupid trick, Robert? ... you cannot evade the issus: a single clock cannot show ... even the point that make you "slow-clock theory" contradictory. ... you'll notice that I took care to explicit the meaning of variables, ...
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