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How do you characterize that “duration”? All you are doing is substituting the word “duration” for the word “time”

Nothing can change without that "duration"

time=change

Not sure what you're asking, Popeye.  Call it an hour, call it anything.  What you call it is irrelevant.  The important point is that, whatever it is, and whatever you call it, it's the same for both clocks.

The duration isn't different for each clock.  The rate of ticking is different, that's all.

Can you see the distinction?

Edited by Moronium
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Wow! So does your boat travel close to the speed of light?   :)   It's a speed boat at c.

Apologies for posting this after OceanBreeze has answered so well but I’d already written it and I need clarification on the Doppler Red shift equation. Special relativity means moving clocks run slow

I suspect you'll like this part, Marco:

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Let me try this another way.

Let's say you have two clocks which do not tick at the same rate, sitting next to each other.  These are not "special" clocks, just a couple of old wristwatches, one of which has not been "wound up" recently. To avoid getting sidetracked by any red herrings, let's assume that they are at the same elevation, and that neither is moving (or that they are both moving uniformly at the same speed).

Now suppose that after a certain amount of time has passed, one clock registers one hour elapsed and the other a half hour.

The "certain amount of time" I mentioned is the same for each clock, right?

Now, to take it a step further, it would still be the same even if one clock was situated on a shelf 12" above the other, right?

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Take two glasses one of which is very tall and has a very small circumference, like a test tube, and the other which is a short, "fat" mug.

Put an equal amount of water in each container and, at a certain age, (say 3) children will invariably tell you that the tall glass has more water in it (because it's higher).

You can pour the water out of one, and then pour the same water back and forth between the two containers.  The child will still invariably say the tall glass has more.

It seems the average child is not able to comprehend the notion of self-identity until they are 5 or 6, or so.  Around that age it dawns on them that the quantity of the self-same water is no more or less than itself, regardless of the size or shape of the container it's in.  It's only then that they will tell you that the amount of water is "the same" in each glass after you pour it back and forth.

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Let's say you have two clocks which do not tick at the same rate, sitting next to each other. ...Now suppose that after a certain amount of time has passed, one clock registers one hour elapsed and the other a half hour.

This is where Einstein's positivistic dictum that "time is what a clock measures (it to be)" leads to trouble.

All objective standards for judgment go out the window.

Which clock is right in this case?  Who knows for sure?  Maybe neither.

But one thing is certain, they are not BOTH right.

Time, as an abstract concept, is something completely different than what a clock measures.

Calibrating a given clock so that it records the passage of time at different rates does not, and cannot, change time itself.

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The H-K expriment , ignoring the gravity effect on the earth clock, is an example of twin paradox permanent age difference, not of "time retardation" due to reciprocal time dilation.

Special relativity means moving clocks run slow. The challenge is which clock is moving, so I hope  this experiment (Keating) carried out in the 70’s using an aircraft heading W and then repeating the procedure heading E, while carrying atomic clocks synchronised with a master atomic clock at an observatory in the United States helps make sense of it:

The clock on the W bound aircraft was travelling against the East bound spin of the Earth, (rather like a person walking the wrong way along a conveyor and not moving very much), while the master atomic clock in the United States was moved faster as it travelled along with the E bound spin of the Earth. The Observatory master atomic clock therefore became the moving clock in this case and ran slow (reading a total of about 96 nano seconds less due to special relativity) in respect to the W bound aircraft’s atomic clock.

The clock on the E bound aircraft was travelling with the East bound spin of the Earth, (rather like a person walking along a conveyor moving very quickly), so became the moving clock and ran slow (reading a total of about 184 nano seconds less due to special relativity) in respect to the Observatory’s master atomic clock.

So to recap, the W bound plane had a relative velocity less than the observatory master, speeding the plane Atomic clocks up, while the E bound plane had a relative velocity greater than the observatory master, slowing the plane atomic clocks down.

The experiment also recorded how clocks were affected by the gravity field with regard to General Relativity.

General and Special relativity 1971 experiment ref: https://en.wikipedia.org/wiki/Hafele%E2%80%93Keating_experiment

Time dilation due to a gravity field using General Relativity equations is painful because if the body causing the gravity well is rotating this has to be taken into account, not to mention other factors. In a nutshell, time on the Earth’s surface (9.8m/s) must be multiplied by a factor of 6.94x10­-10 to find the extra amount of time to add if in deep space because time has sped up. So if the period is 24hours:

24hours = 86,400 seconds. 86,400x(6.94x10-10)=6x10-5seconds a day extra if in deep space

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The Observatory master atomic clock therefore became the moving clock in this case and ran slow (reading a total of about 96 nano seconds less due to special relativity) in respect to the W bound aircraft’s atomic clock.

So to recap, the W bound plane had a relative velocity less than the observatory master, speeding the plane Atomic clocks up, while the E bound plane had a relative velocity greater than the observatory master, slowing the plane atomic clocks down.

I think this is a good summary of the empirical results, but this talk about an Observatory master clock is inaccurate.

The "master clock" used (by necessity) to predict the results actually obtained was not the clock at the naval observatory.  That clock was just another "moving" clock, as you say.  The "master clock" used to adequately explain the result was a hypothetical clock located at the earth's center of mass while not rotating (the ECI). This was the "preferred frame" used to assess the result.  It was treated as being motionless and all other motion, relative to it, was deemed to be absolute motion.  The ECI clock was therefore the one which kept the "true" (undistorted) time.  Ignoring gravitational dilation, it was the one which would always "run the fastest."  Every clock moving with respect to it would be slowed down.  Other clocks would slow more or less based upon their speed relative to the ECI and their (vertical) distance from it.

A presumption of absolute motion, not relative motion, was necessary to explain the results.  Put another way, the theory of special relativity was NOT useful in this experiment as it gave incorrect predictions. The theory of relative motion actually employed was a competing theory which presupposed absolute simultaneity, not the "relative simultaneity" posited by SR.

Treating the observatory clock as the "master clock" with the correct time results in different predictions, ones which do NOT comport with the empirical findings.

Edited by Moronium
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Special relativity means moving clocks run slow.

More accurately, the Lorentz transformations (LT) predict (to a highly accurate degree) that moving clocks run slow. SR uses the LT. but the LT are not SR.

Nor is SR the only theory of relative motion which incorporates the LT.   Competing theories, based on postulates that are radically opposed to those of SR, also use the LT to quantify their predictions.   Confirming that moving clocks slow down therefore does not necessarily confirm SR, as a complete theory.  More than a mere agreement with a portion of the LT predictions is required for that.

That said, it is nonetheless often (inaccurately) reported that the H-K experiment is consistent with the predictions of SR, solely because it demonstrated that clock rates do vary with speed.

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Sorry, I don't even read what you write Moronium. However, I had an interesting thought today. The speed of light is a misnomer. It should be called the max speed of information and since reality= information, c is the max speed of reality. So the max speed of reality is the normal rate of time every frame runs at from its own perspective. The max speed of reality between frames is affected by their relative velocity. If you agree or disagree Moronium, I'll never know because I won't be reading your response.

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Sorry, I don't even read what you write Moronium.... If you agree or disagree Moronium, I'll never know because I won't be reading your response.

That's been obvious from the get-go, or at least from the first time I questioned your erroneous assertions,  eh?  You're hardly alone.  Even those who claim to be "scientists" around here, like Chem, for example, seem to delight in their willful ignorance about the topics they are so quick to opine on.  A-wal is another prime example.  I have, on many occasions, encouraged him to read the H-K experiment for himself.  He adamantly refuses.  Instead he simply, at various time, says:

1.  Such an experiment was never conducted, and I'm just making it up, or

2.  The results of the experiment were obviously wrong and it was done with defective instruments.

He also repeatedly displays a woeful lack of understanding of the fundamental theoretical aspects of SR.  I often direct him to expert websites to dispel his misconceived notions, but he refuses to even look at them.

He has no need for facts or understanding. He has OPINONS, by God, and their correctness is indubitable.

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The great attractor would be more accurate as a universal time, the largest Lagrange points beyond the cosmic event horizon would be an example of perfect frames, not just preferred, an "absolute" relativity.

That would simply depend on the scale you are attempting to get accurate measurements about.  Empirical observations have shown that the "correct" preferred frame to employ is the center of the dominate gravitational mass where the desired measurements are made.

For experiments on or near earth, that would be the ECI.  On Mars it would be ECI (MCI) for that planet.

For measurements made on a solar scale, it is the barycenter of the solar system.  With respect to that point, everything in the solar system, sun included, is "moving," while it is not.

On a galactical scale, the preferred frame is the center of mass for the Milky Way.

I suppose the great attractor would be the logical choice for inter-galactical measurments relating to our vicinity.

On a universal scale, cosmologists and astro-physicists use the CMB as the appropriate preferred frame.  It has been called the "cosmic rest frame."

Edited by Moronium
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Only by a decimal place or two. Good enough for "general" relativity.

The topic here is SR, not GR, although GR is tangentially relevant to to complete analysis of the H-K results.

SR is concerned with time dilational effect due to speed, not gravity.  And the amount of error generated by using SR to calculate that is enormous, not minimal.

SR would actually work out fairly well for translational motion in N/S directions, but if fails miserably for east and west directions.

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Actually no

The event horizon is just the result of what's called a "rindler horizon" and it along with gravitational waves and "dark flow" is what they use to sell us on the existence of dark matter or dark energy particles

That's a completely different topic.  I'm just talking about the preferred frame used to analyze relative motion in transformational terms, and to determine absolute motion, of course.

The CMB is used, for example, to determine the absolute speed of the milky way, and other galaxies, toward the great attractor.  For us, it's about a million miles per hour, as I recall.

I'm told that there are galaxies which aint moving much at all relative to the CMB.  Our galaxy aint one of them, though.

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There IS an absolute frame of reference for time dilation, in which all causally connected lagrangian coordinate for one cosmic scalar can be measured.

Heh, yeah, so you claimed in a prior post, while also claiming that you were the only person in the universe who knows what it is, eh?

Enlighten us.  What is it?

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I won't just give away the ALE

Kay, suit yourself.

Truth be told, I'm glad I didn't have to try to wade through whatever concoction you would have come up with.

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If I had to haul off and venture a wildass guess, I would be forced to conclude that your elevator doesn't go the top floor, eh, Poly?

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Empirical observations have shown that the "correct" preferred frame to employ is the center of the dominate gravitational mass where the desired measurements are made.

Incidentally, this is something Newton instinctively perceived centuries ago.  He said that the only universal (preferred) rest frame would be the center of mass of the entire universe.

Of course he also said we could never detect this so that, as a practical matter, the question was moot.  Long before Einstein, he concluded that absolute motion, in that sense, could never be detected.  Nonetheless, a common misconception is that Einstein "corrected" Newton on this subject. In truth, Einstein, like Lorentz, Poincare, and other prominent physicists of that era, simply agreed with Newton.  Although both Lorentz and Poincare hypothesized that, as a theoretical matter, there was an absolute rest frame (the ether), each agreed that it could never be empirically detected.

Newton used the solar barycenter as a preferred frame from which to calculate the mass and speed of the various planets to an amazing degree of accuracy.  But he still noted that the entire solar system could be moving at great speeds relative to something else.

But, he said, he didn't have to concern himself with that because any such motion would be common to the whole solar system, affect each part equallly,  and therefore not affect the accuracy of his calculations on an inter-planetary scale.

He used the background of the "fixed stars" to ascertain planetary motion.  He called this a "close approximation" of a rest frame for his purposes.

Edited by Moronium

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