bangstrom

Let me rephrase the question. If I send a ray of light in a direction exactly opposite this galaxy, will the light ever reach the galaxy? The universe is curved so it has no "edge".

Enne Malus discovered another difference between light reflected from a smooth surface and a rough surface in about 1800. Light reflected from a smooth surface is both circularly and linearly polarized while light from a rough surface is not. This is how polarized glasses are able to eliminate the glare reflected from smooth surfaces. Also, if circularly polarized light is reflected from a smooth surface, the direction of polarization is rotated by 90 degrees. Light polarized to the right becomes polarized to the left etc.. With linear polarization, the light is polarized in either a horizontal or vertical position, but with circular polarization, the “electro” part of the electromagnetic light wave runs slightly behind the “magnetic” part and how far it is behind makes the wave appear to rotate to either the left or the right. The glasses used to view 3D movies use both linear and circular polarization. Both right and left lenses are linearly polarized the same as sun glasses but the right and left lenses have opposite circular polarization as does the movie projector. This way the projector can project different images for the viewer’s left and right eyes so they see the image in 3D. There is a surprising effect if you look at your reflection in a mirror while wearing 3D movie glasses. If you look at your reflection with just one eye. Say your right eye. The light from your right eye can’t return because the mirror reverses the circular polarization so your right lens appears totally opaque while the left lens appears clear. You can see your closed left eye but not your open right eye.

He may calculate B's clock to be slower because of time dilation but his perception should be that B's clock is running faster because of the Doppler effect. Acceleration in velocity slows time exactly as acceleration in a gravitational field slows time so clock C should be running behind A and B as you explained.

I see the time dilation as genuine and not merely optical and it works both ways. An observer at the tower sees Einstein’s moving clock as running slower due to kinematic time dilation and, likewise, Einstein sees the the tower clock as running slower since he sees the clock tower as moving away from his position. So Einstein sees the tower clock running slower as a SR effect but the most evident change is the Newtonian Doppler effect.

I am here to learn. The question in the OP asked if it is correct that Einstein on a train moving away from the clock tower should see the receding clock running slower? I say, Yes. The answer you gave “ The clock ticked slower because time slowed down, owing to relative motion.” makes no sense to me as an answer to the question and I understand about time dilation. First, should Einstein see the tower clock running slower or not?

Janus is right but your answer to the question in the OP was wrong. Here is the question with your reply below. No, it was not proposed to be an illusion. The clock ticked slower because time slowed down, owing to relative motion. The correct answer to the question is: Yes, Einstein should see the hands on the tower clock moving slower because of the classical Doppler effect. Your answer (in the expansion) makes no sense as stated. You may be thinking correctly but it came out all wrong. If Einstein's clock is running slower, he should see the tower clock running faster than his own but this is the opposite of what he observes. Also, Einstein should see no change to the clock in his own reference frame. Janus is correct that Einstein's clock is running slower than the tower clock but he added the caveat that you must discount the classical Doppler effect from your observation. Einstein can not observe any relativistic change from his own reference frame but he does observe the Doppler effect where the tower clock appears to be running slower.

The classical Doppler effect is the major contributor to the observations. It takes longer for light to reach the train as distances increase so the time between ticks also appears longer. The light appears dimmer with distance because the light is emitted radially and the train captures less of the emitted light as the emission spreads. This is not a part of the Doppler effect. The redshifting of light is a Doppler effect at relativistic speeds. It takes longer for an entire wavelength of light to be detected when the receiver is moving away causing the wavelengths appear longer and shifted more towards the red (longer wave) end of the color spectrum. The same happens with sound waves but at vastly slower speeds. Red shifted light is not necessarily dimmer but it is less energetic than light with shorter wavelengths.

Einstein should see the tower clock ticking slower because he sees the ticks arriving slower at his moving location due to the Doppler effect but the clock did not actually tick any slower. It makes no sense to speak of time as having slowed. The observation of a slower time is real but the actual slowing of time at the tower is an illusion. As Janus said in the quote you cited, “Do not conflate what a observers visually sees via the light arriving from a source with what that observer would conclude it happening at the source.” Observer A should see the clock on the train ticking slower. Observer B should see the approaching clock on the train ticking faster. Observer C on the train should see the clock at A (the origin) ticking slower. B (at the approaching destination) ticking faster. And C (on the train) should see no difference on his clock.

The first observation establishes the orientation of both particles at the instant of observation. That is, the event is non-local. The very first observation destroys the entanglement so, if you know the orientation of the electron in your laboratory, you can’t predict the orientation at another location because the particles are no longer entangled.

MPMin’s understanding of the problem is correct. The clock time will appear to slow from Einstein’s perspective and the clock should appear redshifted. Einstein’s motion away from the clock can not make the clock in the tower tick slower. The clock ticks as normal, but from Einstein’s view the clock does tick slower. Also, from the perspective of an observer at the clock tower, Einstein’s clock ticks slower. But if Einstein’s clock is actually ticking slower, he should see his clock and the tower either keeping time in sync or running faster. There is an illusion here and no clocks are actually ticking slower. Think about it and guess again.

Very true about GR, but relative to ‘What’ is the universe expanding? Or is it expanding at all? I had a goldfish that grew too large for its bowel, but from the perspective of a goldfish, the bowel must have been growing too small for the fish. When a woman puts on a pair of old pair of pants and the pants are too tight, she thinks she must be getting fat. When a man puts on a pair of old pair of pants and the pants are too tight, he thinks the pants must have shrunk. With the universe as a whole, we don’t have a god’s eye view of events where we can view the universe from the great beyond and watch it expand or contract or remain the same so we have no external scale to tell us if the universe is truly expanding or if all the material within is growing smaller. We are like goldfish in a bowel where our only perspective is that of what the universe looks like from the inside and our choice of absolutes is arbitrary because the laws of physics and math are blind to perspective and they do work both ways.

The value of having an equivalent but alternative model to the Standard BB expansion theory is that we can compare one model with the other looking for consensus and also looking for inconsistencies that suggest there may be something wrong with our interpretation of one or both models. I think your model of shrinking matter model suggests some serious problems with the expansion theory but it works both ways. I hope I understand how you find speed of light to be varying in your model but if you apply the same thinking the SMBB you should find that the speed of light is also varies from reference frame to reference frame in the Standard Model. If space expands while time remains the same, the speed of light must necessarily be slowing. My understanding of this is that your model is no more a model of changes in the speed of light than is the SMBB, since in both models, the speed of light should be measured the same in each and every individual reference frame. So how is your model any different from the SMBB? A little known mathematician named Russel Ryerson had a model of contracting matter essentially the same as yours and he said one model is the conceptual and mathematical inverse of the other. This is why they are equivalent and he called his model “Inverse Expansion.” In the SMBB, space is expanding while time remains the same. In your model, matter is contracting, while space remains the same. I explained earlier in my comment of “little meaning” that the measured value of c remains the same in every reference frame and this should apply to your model just as it does to the SMBB. So your model is one of shrinking matter rather than a changing speed of light. As particles in the material world grow smaller, they spin faster, and our perception of time quickens. In the SMBB model, space expands while time remains the same and the speed of light slows from one reference frame to another. In your model, space remains the same while matter contracts and the speed of light quickens from one reference frame to another. One is the simple inverse of the other but we can't go back in time and measure light speed in these older reference frames so the variations are safely ignored. Our observation of c remains the same in both models so neither one can be considered a model of a variable speed of light. The real difference is that the SMBB is a model of expanding space and yours is a model of quickening time.

It is clear that light waves are not “stretched out” in your model but I was asking if light wave emissions are growing shorter with time? That is, progressively shorter starting with the CMB and up to the present time.

That's not an actual rebuttal. You disprove a conjecture by showing that it's not consistent with what we observe. My statement was a comment and not an “actual rebuttal” because the OP makes sense. The “speed of light” can vary from one reference frame to another but the observed value for c should be the same in all individual reference frames. If c is a constant, then (ε0μ0) is also a constant. Separately, e0 and μ0 may be variables but their multiples and ratios should be a constant, just as when c= d/t. Distance and time may be variables but their observed ratio is a constant. This implies that c can serve as a conversion factor for converting between units of distance and units of time. The value of c is essentially the length of a standard meter expressed in seconds. If the sizes of the EM waves have remained constant, then why do present day emissions appear shorter than primal emissions from the CMB? Your model doesn’t have an expanding space to explain why light waves from distant sources have become “stretched out.” Unless, by constant you mean proportional to the shrinking atomic scale.

The “speed of light” is a constant by definition and therefore can’t change. Our standard units of length and time and the ratio c are all mutually defined which makes it impossible to measure the speed of light as anything other than what it is defined to be. But you have the right idea that if matter shrinks, the nature of spacetime must change. The value of c is a constant ratio of distance to time and not necessarily a speed. C can remain a constant if both time and distance remain as the same ratio. The standard length of a meter is defined as the distance light travels in approximately 1/3x10^8 m/s and a light year is defined as the distance light travels in a year. Consider the impossibility of trying to measure the speed of light in meters or over the distance of a light year. This is simple logic that needs no explanation but it is impossible to explain it to anyone who doesn’t immediately find it intuitive. The more one tries to explain it, the more incomprehensible it becomes. If you haven’t discovered this yet... you will. The Doppler shift is no longer considered the cause of distant redshifts. The current explanation is that space itself is expanding and light waves are being stretched out by the expansion of space which is a much different explanation but conventional thinking and calculations remain rooted in the Doppler shift paradigm. Light speed can vary from one reference frame to another, but within all reference frames, the value of c as a ratio of distance to time should remain the same.

The spheres are called “framboids” and here is an extensive article speculating about their possible origins. Large framboids are collections of smaller framboids rather than true crystals. https://www.researchgate.net/publication/313528873_Framboids_From_their_origin_to_application

An old WWII RAF pilot became a commercial airline pilot when he retired from the military. The airport at Frankfort was notorious for its mix of runways and complicated landing patterns. On the pilot’s first flight from London to Frankfort, he was having difficulty following the complicated instructions he was getting from the tower so the frustrated Air Traffic Control officer asked, “Haven’t you ever flown to Frankfort before?” The pilot answered, “Yes, but I never had to land.”

Why would the space travelers 1kg mass be hardly any greater than the same mass for the man in the park? And, why would a material object, either a clock or a weight, moved from one reference frame to another not rescale to its local environment? Also, your scenario would work better with a time traveler than a space traveler. Movement through space slows time so the two aren’t entirely different. Light can’t be detected by any means in the space between signal and receiver so how do we know that light energy even exists in the space between? Mach asked this question as did Berkley long before him. Currently, Carver Mead along with a litany of others are convinced that energy never exists separate from matter.

That is a matter for the Big Bang experts. That is my interpretation of the theory so I am not the person to ask. I find it a strange idea when I think about it.

How does space expand beyond the galaxies? If matter and galaxies both were to expand along with the expansion of space, we would have no observation of an expanding universe. Since we observe galactic redshifts and interpret that as evidence of an expanding universe, the implication is that the galaxies must be remaining the same size while space expands beyond the perimeter of the galaxies. The galaxies are not expanding because they are gravitationally bound and are not affected by expanding space. In the contracting matter theory, the universe is interpreted as being enormous in size from the beginning but not expanding. Instead of expanding space, the entire material world, from atoms to galaxies, is growing smaller so we have the illusion of expansion together with the observation of galactic redshifts because atoms are progressively growing smaller with time. Going back in time, earlier atoms were larger and emitted light in longer wavelengths proportional to their larger size. In the BBT, space is expanding past non-expanding matter, but in the shrinking matter theory, matter is uniformly growing smaller within a background of static space while remaining proportional in size to the rest of the material world. The first is a model of expanding space and the second is a model of quickening time but the picture works the same from either perspective. You are right, they are cousins. I wasn't aware that Joan Baez had such an ilustrious father.

I said mass remains the same. I never said anything about a reduction in mass. Losing empty space increases density but no mass is lost since empty space has no mass. I never proposed a decrease in mass or keeping density the same. You are reading nonsense into what I wrote. Think about what happens in the BBT. When space expands within a galaxy while the galaxy remains the same size, the fields don’t expand with space, they remain with the galaxy. In a “shrinking matter” theory, when matter contracts, the fields contract. The fields remain with matter. What an amazing family! John and Joan Baez are brother and sister. I don’t see the scenario playing out that way but your conclusion is right. In the “shrinking matter” model, at the time of recombination, planets had not yet formed but there were H atoms so let’s follow the progress of the atoms. If the atoms downscale by 1000, they would be 1000 times smaller and no less massive but with far greater densities. They would be the normal atoms we see today except that they were 1000 times larger and therefore less dense in the remote past. In another 13 billion years, there could be some black hole issues. Normally physical laws don't change but matter itself could be vastly different at the extremes

What I have written has been largely in response to considered problems. What has not been addressed?. Are you saying they don't scale or they do scale? I see space and time scaling in both 3D and 4D and matter scaling proportionally which is why the physics remains unchanged. Your claim is not my claim. But I do agree conservation laws hold locally because all changes remain proportional from one reference frame to the next. Why would the laws of gravity be any different. For convenience, we are justified in considering gravitational sources as single points. If particles become a smaller it should make no difference to gravity or changes in shape. But it should involve all material in the universe growing hotter with time and we observe this as a rise in temperature from the primal temperature of 3.73K. For a long time I thought it was simply a “What if ?” that helped my understanding of the BBT but now I see it as the answer to several problems with the Standard Model. But that is another story. I wrote my response without taking time to consider it properly. That is why I asked for your expertise to take a look at it. Not because I was trying to explain away something I didn’t understand. I favor a Machian approach to physics which tries to eliminate as many “metaphysicals” as possible and modify or remove any laws of physics that do not hew closely to experiment and observation. That is a good matter for consideration.

Does this make sense? Caracal gave the example of two men in two jars with time varying at different rates in each jar. Neither man notices a change in his own jar but they can look out and see that their clocks are running at different rates and their units of length no longer match. The radius r of an atom in both jars is r = ℏ2/me2 and the value of e in both jars is e=L3/2M1/2/T. The atoms in the jar with the faster rate of time should be smaller than in the jar with the slower time because the value of e is greater where e= L3/2M1/2/T when the length L is shorter, and momentum M is greater, and the rate of time T is greater.

It does for uniform solids but I don't understand this as a uniform principle.

(My emphasis.) Who gave it? And are you a co-author? x-posted with Swansont. In any case, mass and length scale together due to relativity and quantum mechanics, so no, you can't pull this off. Unless you explain very good reasons why ℏ and c (speed of light) are irrelevant in physics. The “given” of an expanding universe began with the interpretation of Hubble’s observation of distant galactic redshifts as recessional velocities. Hubble himself was never convinced that the universe was expanding because he could see other possible explanations. I am not a co-author of anything. What do you mean by “mass and length” scale together? Did you intend to say time and length scale together? It has never been my claim that ℏ and c are irrelevant. My interpretation is that the space traveler could know he has been transformed if he can observe an increase in the rest mass of a massive body. However, if his atoms are smaller and therefore more dense and time has quickened, there should be an increase in the objects inertial mass but he would not be able to observe the change because his rate of time is faster When you say mass has increased, do you mean rest mass or inertial mass or both? Also, Wetterich has a contracting model with quickening time where he claims that mass increases with time but I don’t know enough about the model to claim I understand it. https://bigthink.com/articles/the-universe-may-not-be-expanding/ arXiv:1912.00792v4 [gr-qc] 30 Apr 2021 The great emptiness at the beginning of the Universe “The beginning is vacuum, characterized only by average values of fields and their fluctuations. This is a very quiet epoch with only a very slow increase of particle masses. In the infinite past all particles become massless.”-Wetterich Wetterich also has this to say, “For standard inflationary models we find that the big bang singularity of homogeneous solutions is an artifact of a singular choice of fields.”