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Time and c

Re: Time and c

Postby Good Elf » Thu Aug 03, 2017 7:06 am

Little Bang wrote:I read the article and in every case they use a clock to make their calculation and it was in Earth's gravity well. My point being that those will be different on the moon.
No they won't. The calculation for C will always be the same. What you have not understood is "different to what"? If you are talking about one clock that is measuring the speed of light... the answer is the speed of light is still exactly C. Every other speed is different but not this one. All Clocks run faster on the Moon compared to identical previously synchronized clocks on the Earth because all clocks use the speed of light intrinsically. "You", as a biological mechanism, use the speed of light intrinsically. All measurements you make have already used the fact that the speed of light is a constant and has a value of C. All sub-atomic processes on the moon run faster than all subatomic processes on the Earth, however as Relativity insists that your measurements are internal not external (internal to the one clock), but it is only when you compare a clock placed in different places in different states of motion and undergoing different accelerations that you notice the difference in the values of their separate dials for elapsed time of a clock placed in a different place and undergoing different motions and accelerations. Measurement of time is singular not dual. One clock measures just one time, local time. The subtle point is time runs faster on the Moon relative to time on the Earth. You actually age faster on the Moon THAN A PERSON ON EARTH. That is not a factor due to your biology, it is time itself that is actually running slower. You need to understand your life processes and every process in your local vicinity see no differential change and though time for you is running faster than if you were on the Earth, your experience of time is identical to the person on earth, your lives "tick" at different rates but, one gets to the end of his life sooner than the other simply because the ticks are shorter only when compared to the "ticks" in the other clock. Unlike the two of you having "bad clocks", these clocks are both equally good and the experience of time is exactly the same, for the two of you a second is still a second and this also goes for your individual psychological experience of time.

On any clock anywhere your activities are such that you accomplish the same amount of activity in a unit of time anywhere and everywhere, nobody is cheated out of "time". This is not any different than standing on different steps in a stairwell of a building which is above the surface of the Earth but more extreme, because gravity is different on the different steps and also because the Moon is in high speed motion around the Earth, the clocks on the Moon are affected... but not the fundamental constant C. Also note when you correct for Relativity you will get exactly the right answer that theory predicts according to Special and General Theory of Relativity. The assumption in Relativity is the speed of light is a Universal Constant C. Please understand this is a fact. If you return to Earth by traveling down the gravity well, and compare with a clock left on Earth there that you synchronized with your clock you had with you on the Moon before you left it, then what you say is true. But this is not what you said... this is not trivial... you need to get your head around it. According to Relativity, this is not the way you make measurement. A measurement of time is made "in place" and clocks have one dial attached to the clock for a reason... OK. There is a need to have a means of Einsteinian clock synchronization and that process is also not trivial (often "glossed" over). If you "forgot" to synchronize clocks before you left there is no way to tell exactly what that differential in time was after the fact without synchronization of clocks (you may look a tad younger than your identical twin but how can you really tell?). Traveling fast and living at the bottom of a gravity well only affects differential aging not the "process" of aging. The weather on the Moon is not responsible for how you age there it is due to the frames in relative motion and relative acceleration. It is all RELATIVE you see.
Your question:
If I take all my equipment to the moon and use the same clock that was used on Earth and measure c I will get a slower value for c because my clock is running faster than on Earth?
Count the number of clocks... it is just one clock. It has one dial and it can only be in one place at one time. SO: No you won't, you are measuring the speed of light on the moon and you will measure exactly the same velocity for light you measured on the Earth (all other factors being equal... for example it is measured in a vacuum and the clock itself is not affected by the gravity as any good clock should be). I kid you not... please get your mind around this phenomena. The speed of light is always measured to be the speed of light (in a vacuum). In every conceivable place in the universe regardless of the state of motion or the gravity, in a vacuum... the speed of light is always C.

For local human observers there is no way to know you are ageing faster than "normal" (simply because it is still perfectly "normal") and the disintegration of atoms will be measured exactly the same. Some things on the Moon will be different such as a swing on the Moon moves slower than on the Earth because the gravity is 1/6. Recall that this is a kind of pendulum but it is not a true way to measure time in anyplace where acceleration due to gravity has changed. For the same reason you can throw a ball further... etc... what you will not measure is any change in the speed of light. This is something that can even be measured on the surface of the Earth without even going to the Moon... it is a fact not only here but everywhere.
Aa' menle nauva calen ar' ta hwesta e' ale'quenle
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Re: Time and c

Postby Good Elf » Sat Aug 05, 2017 11:33 pm

Hi Little Bang,

There is another way to look at this. Perhaps this very recent discussion on Ethan Segal's Starts with a Bang Blog and written by Sabine Hossenfelder may help...

If the Universe is expanding, then why aren’t we?
The atoms, planets, stars, and even galaxies aren’t expanding, even though space is. How come?
Sabine Hossenfelder wrote:It’s tough to wrap your head around four dimensions. Scientists have known that the universe expands since the 1930s, but whether we expand along with it is still one of the questions I am asked most frequently. The less self-conscious simply inform me that the universe doesn’t expand but everything in it shrinks — because how could we tell the difference?
I think she just insulted us folks? He he he... good for her. However she knows what she is talking about, that means we need to quieten down listen up. If we are discussing the true "big picture" I lean to the POV or "attitude" Hitler took when confronted with two opposing (untrue) theories of The Eternal Ice and The Hollow Earth, which cannot be simultaneously true at the same time, in a political counter move to neutralize the influence of Einstein's Theories and "Jewish Physics", declared "Maybe they were both true" (...and by implication Einstein wrong). To the Third Reich, and all the citizens who burned all the books, this did seem to many a "most satisfactory" outcome, the human mind is not immune to the strange disturbing effects of mysticism and did in part lead to their downfall. Of course some may regret today that they had partaken in that rather stupid political affair and also the linked persecution and senseless mass murder of the Jews. More so for the Japanese, it would seem, the other part of the axis powers, because they experienced the results of the true error of a bad series of choices that led inevitably to the darkness that was Hiroshima and Nagasaki. Of course this is probably the only time I can think of I have ever accepted any small aspect of Hitler's POV... so don't get excited folks. Einstein is "mostly" right but it is known that his theory fails at the Galactic Scale and also the Sub-atomic Scale. Black Holes and White Holes and Wormholes changes everything, it is just that we don't know exactly "how" they change everything for the present. On the other hand there is no reason to think the speed of light is ever measured to be locally different anywhere in the Universe simply because the scale is fixed and it is at the measurement scale we have decided on to measure it. We don't know what really happens inside a black hole for example.

So I urge you all to read the article linked above. There are two images in the article linked that help to illustrate how to slice this problem but in the end the only slice is the one we usually accept that the speed of light remains the same and the space around us changes. The only limitation to this POV is it does not allow for quantum effects and it does not account for the failure of Einstein's Theory to explain the rotation figure of galaxies... excepting those limiting scales this problem is very well understood. Check out other threads on this site for treatments of these other limiting problems. Other interpretations make little or no sense. However I agree that asking the questions such that the Universe should make sense to us is the wrong way around. Consider that the Ancient Greeks believed beams of light were emitted from our eyes to illuminate what was seen, and when we were not looking there was no light... man being the center of the Universe and all. It certainly made a lot of "sense" to the Greeks. For hundreds of years this idea was considered "most satisfactory". Unfortunately it did lack a tad on the experimental side of things. Of course you need only stare at the Sun for a few minutes to realize that man is not the center of the Universe and that all light does not actually originate from him. We have similar, less obvious problems with science today. We are not necessarily "blind" from staring at the "Sun", but sometimes we are blinded by the rationality of the Universe and particularly of the power of mathematics. Some eventually come to accept that the theory of mathematics is greater than the observations or experiments and they forget to check on "reality". But we should not confuse "our reality" with the way the Universe Herself sees "Her reality", She is not bound to follow the mathematics and there is a lot of failed mathematics. We also have difficulty discussing these matters with the public because there is no natural "teacher - disciple" relationship existing "out there" so everybody with an ego still thinks they are at the center of the Universe and feel the need to explain that point to everybody around them that they are the smartest people they know. He he he... The Quentin Crisp Quote is also highly amusing and still very true ...
“In an expanding universe, time is on the side of the outcast. Those who once inhabited the suburbs of human contempt find that without changing their address they eventually live in the metropolis.” -Quentin Crisp
And that is as it is, and as it should be. The outcast scientist of today may eventually end up being the "norm" and the "insider" in the distant future where the "mob" will once again embrace sanity and truth after a long period of unrest and pain.

So I urge you all to read the blog by Sabine Hossenfelder it may help with this question because it is more technical and focuses on just solving the problem not explaining where it falls short.

Image
How matter (top), radiation (middle), and a cosmological constant (bottom) all evolve with time in an expanding Universe. Image credit: E. Siegel / Beyond the Galaxy.
Hmm... maybe?
Aa' menle nauva calen ar' ta hwesta e' ale'quenle
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