[Bogie_smiles]

The real absolute time could be many magnitudes faster than that. Our entire universe could be within some outer "universe" such that the whole of our universe is running at snail pace. This would make sense too when you think about "instantaneous" action at a distance with quantum stuff.

Those are interesting thoughts, but instantaneous action at a distance is not possible in the ISU, just like a perfect vacuum is not possible. I do like to go on about my quantum thinking, and my version of quantum gravity, and yes, there are energy density levels where actions occur more rapidly than in others, clocks run faster, gravitational waves go faster, but never instantly; not even at the quantum level in the ISU. There is always a time delay as long as there is energy density, and there is always some level of energy density because there can be no perfect vacuum.

If you don't have that faster time, you can't have a time slowed by energy density because it isn't running slower than the faster time that the model doesn't have.

I tried several different responses to that, but none of them seemed to make sense, lol.

If you make sure you have removed absolute time from the simulation, the simulation will cease to function correctly. Indeed, it will fail to function altogether. You cannot have coordination of different "times" without one of them governing the other(s).

I can believe that, but I’m not certain …


A Group of Blind Men and an Elephant

A group of blind men heard that a strange animal, called an elephant, had been brought to the town, but none of them were aware of its shape and form. Out of curiosity, they said: "We must inspect and know it by touch, of which we are capable". So, they sought it out, and when they found it they groped about it. In the case of the first person, whose hand landed on the trunk, said "This being is like a thick snake". For another one whose hand reached its ear, it seemed like a kind of fan. As for another person, whose hand was upon its leg, said, the elephant is a pillar like a tree-trunk. The blind man who placed his hand upon its side said, "elephant is a wall". Another who felt its tail, described it as a rope. The last felt its tusk, stating the elephant is that which is hard, smooth and like a spear.

________________

Ok, I know I’ve gone philosophical again, but the challenge for each of us is to try understand another man’s “elephant” without being able to see it. Until we communicate, we are just the blind leading the blind. It wouldn’t surprise me to find out that we are all in the Group of Blind Men from time to time. After all, we are talking about the strangest “elephant” of all, the as yet unknown nature of the universe, and only being able to know it from what someone else says their piece of it feels like.

[Halc]

The masking would never be perfect, so it turns out that it isn't a problem, but let me explain the line I was thinking down. Imagine a glass tank with a light clock in it. Fill the tank with water and the light clock runs slow. Empty the tank and the light clock speeds up again. Now send a signal in and repeat the experiment. The signal slows down, but the frequency won't change, so the light clock (if it has a detector that can measure it and time it against light clock time) will detect it as having a higher frequency - exactly as you say. However, if you have a changing gravity well that engulfs the signal over a long distance from the side, that will slow it down such that the frequency is lowered.

It will not. So long at the path doesn't change, the frequency of the light cannot possibly change in any one frame.

Sure, the frequency is different as measured by a slower clock, but that's the clock being different, not the light.

[Bogie_smiles]

I have to finish watching this, so I’m putting this in the Dogma thread for future reference:

[David Cooper]

It will not. So long at the path doesn't change, the frequency of the light cannot possibly change in any one frame.

Picture a tank of water a lightyear long with a laser beam skimming over its surface. Raise the level of the water in just one second such that the light beam is now in water rather than air. Has there been an instant change in the number of waves in the light? No. Has the light slowed down? Yes. Has the frequency dropped? Yes, though not  for the light entering the tank at the end. You couldn't actually do that with water as it would reflect the light away on contact when you change the water height, but it could work if done with a changing gravity well instead, and the change in frequency would for a while match the change in the detector's clock (a light clock) such that no change in frequency would be detected by that observer even though there would be a real change in frequency.

Note too that the reverse happens when the water level is lowered - if we wait until all the light in the water has entered at the end rather than being engulfed by the water-level change, when we lower the water (again in a second), the frequency of that light will genuinely be higher (until we run out of all the light that had been passing through water).

[Halc]

It will not. So long at the path doesn't change, the frequency of the light cannot possibly change in any one frame.

Picture a tank of water a lightyear long with a laser beam skimming over its surface. Raise the level of the water in just one second such that the light beam is now in water rather than air.
...
You couldn't actually do that with water as it would reflect the light away on contact when you change the water height, but it could work if done with a changing gravity well instead, and the change in frequency would for a while match the change in the detector's clock (a light clock) such that no change in frequency would be detected by that observer even though there would be a real change in frequency.

Pretty devious.  The water won't work for the reasons stated, and gravity can't just be switched on, but it sort of can if you have a pair of massive rods that can be set close by or further away.
I think it is better done with something like letting gas in (from all sides) that changes the refractive index without the problem of the surface level reflecting the beam away.  I also imagine some solid that changes its refractive index when a charge is applied to it.  This might actually exist, used as sort of an electrical lens with solid state focus.  Point is, I'm not going to attempt to invalidate this interesting example.

Has there been an instant change in the number of waves in the light? No.

Very questionable.  Light doesn't come in waves, it comes in photons.  So before the laser has the beam in sync and it comes out as essentially one countable wave.  I suspect our alteration will just result in photons that are no longer in sync, and thus a count of the number of waves is meaningless.

Has the light slowed down? Yes.

Mostly yes.  If we do it with gravity, it isn't slowed by a local measurement, but you have this absolute idea of speed, so I'll say yes, it slows down.
That means that the pipe is filling up.  It has these spread-out photons, and a year later it is full of synced packed photons.  After about a year, the output will abruptly resemble the original beam.  Until then, what do we see coming out, moving once again at speed?  A less bright light of the original color?  Any given photon has the original energy, but there are not as many coming out, so that's my guess.
Turn off the pipe (gas out or gravity away) and it takes a year to empty the excess photons, so the output is extra bright for a year.

Has the frequency dropped? Yes, though not  for the light entering the tank at the end.

Questionable again.  The number of photons going by per second mid-pipe has dropped at first.  Not sure how you would measure the frequency of a photon while still in there.  I think it depends on if gas or gravity was the agent.  Expose it to photographic film and see what color it shows.  Would film in the gas show different color than film in the gravity field?  How big of refraction/dilation would be needed to tell the difference?
Yes, they have spectrometers, but it is sort of like measuring the beam after it exits the pipe, not while still in it.

[David Cooper]

The water won't work for the reasons stated, and gravity can't just be switched on, but it sort of can if you have a pair of massive rods that can be set close by or further away.

If you have a gravity well with changing length contraction on it due to the source(s) making rapid changes in direction of travel, then you effectively have gravity being turned up and down, and the change can be rapid and near-instantaneous along a long length of the path the signal's travelling along (perpendicular to the gravitational source).

Light doesn't come in waves, it comes in photons.

It has a wave nature with crests and troughs. A measurement of frequency is (at the lowest level) a measurement of how many crests arrive in a given length of time. The distance between two crests doesn't change as the gravity well changes shape.

Not sure how you would measure the frequency of a photon while still in there.  I think it depends on if gas or gravity was the agent.  Expose it to photographic film and see what color it shows.  Would film in the gas show different color than film in the gravity field?  How big of refraction/dilation would be needed to tell the difference?

With gravity, it's easy - the film will have its functionality slowed and the crests will arrive less often, the two effects cancelling each other out. With the tank of water (or gas) and a light clock, what we could do to measure the frequency is use the light in the laser beam for the light clock too, splitting some out from it, but because the two light beams are clearly the same frequency, there isn't any need to bother comparing the two - the effect of the slowing must automatically be masked, though only temporarily due to the curve in the shape of the gravity well. In a real case, the masking would be imperfect, but it could for certain geometries make the effect we want to detect much harder to pick out.

[Halc]

If you have a gravity well with changing length contraction on it due to the source(s) making rapid changes in direction of travel, then you effectively have gravity being turned up and down, and the change can be rapid and near-instantaneous along a long length of the path the signal's travelling along (perpendicular to the gravitational source).

I read that about 6 times and could not figure out what you're trying to describe.

[Light] has a wave nature with crests and troughs. A measurement of frequency is (at the lowest level) a measurement of how many crests arrive in a given length of time. The distance between two crests doesn't change as the gravity well changes shape.

This seems like conjecture, and in this example, it might not turn out to work the way you're describing it.
Surely light coming from a star at color X is not all in phase, and measurement of the wavelength of it isn't done by counting crests over time.  Twice as much green is still green.  I suspect they measure the energy of each photon and extrapolate the wavelength from that.  That's how eyes do it.

[David Cooper]

If you have a gravity well with changing length contraction on it due to the source(s) making rapid changes in direction of travel, then you effectively have gravity being turned up and down, and the change can be rapid and near-instantaneous along a long length of the path the signal's travelling along (perpendicular to the gravitational source).

I read that about 6 times and could not figure out what you're trying to describe.

Picture a spherical gravity well. Draw a circle to represent it on paper, and the line will represent a contour of equal gravitational pull. Now take the central object which generates the gravity well and move it at 86.6c across the page, or imagine the page moving at that speed so that you don't have to move the object. The gravity well must contract to half its rest length in the direction of travel, so if the object's moving upwards, you should imagine the page moving down instead and the circle should be contracted into an ellipse with its shortest diameter half the size of its longest diameter (if diameter's the right word to use when dealing with an ellipse).

Now, there could be two black holes of equal mass forming our object, and they're orbiting each other, but both of them will always be moving in opposite directions and will have length contraction applying on them in the same direction. A quarter of an orbit further on, the length contraction will be applying perpendicular to the way it was applying before. What you'd actually get would be like an ellipse rotating.

Now, draw a dot somewhere inside the original circle, but outside of the original ellipse. Then rotate the ellipse and visualise the line crossing the dot. Zoom in on the dot and observe how the line that crosses it looks more and more straight. For the dot and the space to either side of it, gravity is effectively being turned up and down just as if someone was controlling it with a slider switch. If you do this with the dot far enough away from the black holes, the changes in the speed of functionality of the dot's light detector will be masked by the changes in the speed of the laser light, making the frequency appear constant.

[Light] has a wave nature with crests and troughs. A measurement of frequency is (at the lowest level) a measurement of how many crests arrive in a given length of time. The distance between two crests doesn't change as the gravity well changes shape.

This seems like conjecture, and in this example, it might not turn out to work the way you're describing it.

If light is a wave, each photon must be spread out over a distance with a frequency which manifests itself as a side-to-side movement of the wave. If you try to turn all of that into nothing more than point particles, the frequency is going to be lost, and so will the ability to red or blue shift it.

Surely light coming from a star at color X is not all in phase, and measurement of the wavelength of it isn't done by counting crests over time.  Twice as much green is still green.  I suspect they measure the energy of each photon and extrapolate the wavelength from that.  That's how eyes do it.

To detect sound of a specific frequency, you can do it by having something that resonates at a particular frequency so that the crests and troughs (which are the same thing if we aren't dealing with surface waves) cause it to move to and fro in response to the wave passing. Have lots of these things, like hairs in the ear which are tuned to different frequencies, and you are effectively identifying frequency by "counting" crests. If two lots of the same frequency of sound arrive simultaneously, they can cancel each other out and not be detected, but they can also add together and make a stronger signal. In the same way, two photons can be less easy to detect than one if they happen to cancel each other out at the detector - all the energy is still present, but it can be made incapable of interacting usefully with the detector in such a case, so the only energy that can be counted up is the energy transferred to the detector, making something in the detector move differently (i.e. an electron). Send ten photons in at once and there's very little chance of them all being cancelled out entirely, but most of the signal will still be missed due to it being cancelled out. Crucially though, the more photons that are involved, the bigger the component of uncancelled energy there will be able to drive the detector. If the energy absorbed has to be single photons, then you need to have some kind of quantum system which allows the photons to be provisionally captured and not captured at the same time, and then you have a simplification where the state is simplified, meaning that some of the photons in two states lose their captured form (and continue on unaffected by the provisional interactions with the detector) while others lose the uncaptured form (and become fully captured).

[Halc]

Picture a spherical gravity well. Draw a circle to represent it on paper, and the line will represent a contour of equal gravitational pull. Now take the central object which generates the gravity well and move it at 86.6c across the page, or imagine the page moving at that speed so that you don't have to move the object. The gravity well must contract to half its rest length in the direction of travel, so if the object's moving upwards, you should imagine the page moving down instead and the circle should be contracted into an ellipse with its shortest diameter half the size of its longest diameter (if diameter's the right word to use when dealing with an ellipse).

Now, there could be two black holes of equal mass forming our object, and they're orbiting each other, but both of them will always be moving in opposite directions and will have length contraction applying on them in the same direction. A quarter of an orbit further on, the length contraction will be applying perpendicular to the way it was applying before. What you'd actually get would be like an ellipse rotating.

OK, I got all that.  Orbiting black holes are a lousy example since each one deforms the ring of equal potential of the other, so it isn't a circle anymore.  But just a fast-moving Earth has such a squashed elliptical orbit for the moon for instance.

Now, draw a dot somewhere inside the original circle, but outside of the original ellipse. Then rotate the ellipse and visualise the line crossing the dot. Zoom in on the dot and observe how the line that crosses it looks more and more straight. For the dot and the space to either side of it, gravity is effectively being turned up and down just as if someone was controlling it with a slider switch.

OK, I get that, but what does the dot represent?  What puts a beam of light at the dot for instance?  Nothing can, because it is only the perspective that is changing, and the dot moves with that change, staying outside the circle.

If you do this with the dot far enough away from the black holes, the changes in the speed of functionality of the dot's light detector will be masked by the changes in the speed of the laser light, making the frequency appear constant.

I don't get this, for the reason stated above.  I think you're picturing two black holes, but there is no aiming a beam of light at the dot, which is not a fixed location.  You aim it near one of the singularities or not.  Nothing is changing a perspective.

[Light] has a wave nature with crests and troughs. A measurement of frequency is (at the lowest level) a measurement of how many crests arrive in a given length of time. The distance between two crests doesn't change as the gravity well changes shape.

This seems like conjecture, and in this example, it might not turn out to work the way you're describing it.

If light is a wave,

Light has a wave-like nature in some ways.  I don't think anybody says light is a wave.  Waves are not things, they're effects of multiple things.

If light is a wave, each photon must be spread out over a distance with a frequency which manifests itself as a side-to-side movement of the wave. If you try to turn all of that into nothing more than point particles, the frequency is going to be lost, and so will the ability to red or blue shift it.

Light isn't point particles either, despite it having particle-like nature at times.  You seem to be attributing classical properties to a very non-classic entity.
I think you need to consult what QM says about what would happen, and I don't claim to know what QM says about it.  It would be something on the order of an alteration of the wave function of a given photon, and then the aggregate effect of all those measurements when they're finally taken, and not until then.

To detect sound of a specific frequency, you can do it by having something that resonates at a particular frequency so that the crests and troughs (which are the same thing if we aren't dealing with surface waves) cause it to move to and fro in response to the wave passing.

Resonance yes.  Eyes (a 2-D matrix) resonate at three frequencies and signal processing does the work in between.  Ears (a 0-D matrix) resonate at thousands of frequencies, which do a mechanical Fourier transform on the waves and send that result to the signal processor.
Not sure how the telescopes do it, picking out very specific frequencies with enough resolution to detect the dark absorption lines in them.  Something far more fine grained than what eyes do.  It matters little, except we have to decide if the detection is done inside the refracting/dilated material, or outside.  Eyes for instance are outside: 500 nm light looks the same underwater as it does in a vacuum, assuming eyes were sensitive enough to detect the subtle difference.

In the same way, two photons can be less easy to detect than one if they happen to cancel each other out at the detector - all the energy is still present, but it can be made incapable of interacting usefully with the detector in such a case
...
Send ten photons in at once and there's very little chance of them all being cancelled out entirely, but most of the signal will still be missed due to it being cancelled out.

I agree sort of, but then why does focused light from a random source (the sun say, which hardly puts out synced laser light) not just cancel itself to almost nothing?  No, it fries the ant.  Most of the signal does not in fact go missing.  Where would the energy go if it canceled?  Seems to violate conservation.

Anyway, not saying you're wrong.  I'm not an expert in such things, and have no real prediction about what science says should happen if you do your thing with either a refractive substance or a gravitational change.

[David Cooper]

Orbiting black holes are a lousy example since each one deforms the ring of equal potential of the other, so it isn't a circle anymore.

If you're close to the black holes, that would be messier, but they may only be a few tens of miles apart while the observer could be a million miles away.

OK, I get that, but what does the dot represent?

The dot is the observer, sitting in the gravity well(s) of the black holes. A signal comes to the dot from a great distance, perhaps directly overhead (perpendicular to the page). The dot can either hover in position, or it can slowly orbit the pair of black holes.

I think you're picturing two black holes, but there is no aiming a beam of light at the dot, which is not a fixed location.  You aim it near one of the singularities or not.  Nothing is changing a perspective.

Our observer is ignoring the black holes and is looking at the signal source instead. As the gravity wells change shape, the observer's functionality speeds up and slows down. The signal, which could be a laser beam, operates at a constant frequency (and the frequency of the light is always the same in proportion to the frequency of pulses, so you could monitor the pulse rate instead of the light frequency if you want - this allows you to determine the frequency by counting pulses directly.

By the way, now that I'm picturing a rotating elliptical gravity well, I realise that the straight line (a contour line of depth in the well) crossing the dot will be at a different angle for when the dot is going deeper and when it's going shallower, so anything approaching perfect masking of the effect is impossible.

Light has a wave-like nature in some ways.  I don't think anybody says light is a wave.  Waves are not things, they're effects of multiple things.

How does it work with radio waves? What does an aerial do, and what does an antenna do when transmitting? We get movement of electrons, and something makes them move to and fro at a frequency. A wave is produced by moving the electrons in this way, and a wave being absorbed causes electrons to move in this way too. The manner of movement of the electrons sends out sine waves. Some kinds of radio pick out radio waves with a specific orientation, just like using a polarising filter with light.

]Light isn't point particles either, despite it having particle-like nature at times.  You seem to be attributing classical properties to a very non-classic entity.

Then you have a distribution of the particle which has the frequency built into that distribution, just like a wave.

Ears (a 0-D matrix) resonate at thousands of frequencies, which do a mechanical Fourier transform on the waves and send that result to the signal processor.

I'd call it an mechanical alternative to a Fourier transform. I wrote a program to analyse sound which works more like the ear instead of using the usual FFT method, and it produces good results (unsurprisingly, given that we know the ear does a good job). I simply do a lot of additions and subtractions with the results going into buckets which record the amount of resonance for the frequency they're tuned to.

I agree sort of, but then why does focused light from a random source (the sun say, which hardly puts out synced laser light) not just cancel itself to almost nothing?  No, it fries the ant.  Most of the signal does not in fact go missing.  Where would the energy go if it canceled?  Seems to violate conservation.

The unbalanced component will always be bigger (on average) for a given amount of energy in the signal, just as happens with a choir singing - they don't cancel each other out entirely, although to a large extent the signal is cancelled out at any given location, the energy passing without its full power being detected by the ear. A person standing behind you will hear a different signal from you, some of what you heard being cancelled out while some of the stuff you missed is audible to them. I clearly don't understand this stuff well enough though, because in the light case, if the uncancelled component is absorbed by the atoms nearest the surface of the ant, the rest would continue to cancel each other out all the way through it and then go deep into the ground beneath it too, so that might be a good topic for a new thread.

[Bogie_smiles]

My own model of the universe is one that is infinite, eternal, and on a large scale, the same every where (homogeneous and isotropic). The “sameness doctrine” that I invoke describes the universe as a multiple big bang landscape, and says that no matter where you are in this infinite expanse of space and time we call the universe, the  process of big bang arena action will be playing out around you. You will be in an active big bang arena like we observe in our Hubble view, or somewhere that is involved in the early stages that we would call the preconditions to a big bang.

That is why I picked up on the “What happened before the Big Bang” thread over in the Physics, Astronomy & Cosmology sub-forum, started by “guest48150” who seems to have left TNS all together (leaving his thread with the classic title adrift). I saw it as an opportunity to discuss preconditions in a hard science sub-forum, and so I brought up the cold spot.
https://www.thenakedscientists.com/forum/index.php?topic=75868.msg565389#msg565389