At Rest with our Hubble view

[quantum_wave]

I can't concur with anything like a big crunch I'm afraid.

The distinction here is getting into a more detailed level of my so called model that you may be unfamiliar with, but that I have hypothesized about time and time again. Even people ignorant of most of my so called model may have picked up on how I describe a big crunch. You might be thinking of the cyclical model featuring a repeating bang/crunch/bang universe of finite energy that expands and contracts, bangs again and expands, and then contracts again on a potentially infinite time scale. I think such a model will eventually fail because it can't explain how 100% of the energy of the past cycle can be recaptured into the next big crunch, IMHO.

My so called model is quite different in that the big crunch that preceded our big bang was due to the merger and gravitational collapse of galactic material from two or more similar expanding big bang arenas in pre-existing space. No need for space to collapse of for some unidentified form of contraction to overcome the observed expansion momentum of the galaxies and galaxy groups.

 

[quantum_wave]

But we can still have a civil discussion about cosmology. That's what forums like this are for. And hopefully we all learn something. I know I've learned a lot from forums like this.

And I hope you will remember that when the moderators finally grant the request of several members, including me, to move the thread to Alternative Theories.

 

[quantum_wave]

YES. Quantum-Gravity should be able to explain both QM and GR. I think QG(quantum-gravity) is not yet discovered.

Well, we are in a waiting game then. And in a way, that waiting game has been part of the stimulus for me going off the mainstream grid. Quantum gravity is not yet discovered, it might not just reconcile GR and QM, it might even supersede the full bodied GR theory because curved space-time could be replaced by a quantum mechanism, IMHO.

 

[hansda]

Well, we are in a waiting game then. And in a way, that waiting game has been part of the stimulus for me going off the mainstream grid. Quantum gravity is not yet discovered, it might not just reconcile GR and QM, it might even supersede the full bodied GR theory because curved space-time could be replaced by a quantum mechanism, IMHO.

I dont know if you are also trying for alternative to QG.

 

[quantum_wave]

I dont know if you are also trying for alternative to QG.

You might be perceptive enough to come up with that perspective. It would normally surprise me if someone recognized that possibility because it requires reading what I say, lol, but your are not like the closed minded mainstream apologists who shoot from the hip. The answer is that, like you said, there is not yet a quantum gravity solution. You might then grasp that according to how I characterize my hobby, if the mainstream community has not reached a consensus on quantum gravity, then I consider it fertile ground for my personal hypotheses about the quantum cause of gravity.

 

[hansda]

You might be perceptive enough to come up with that perspective. It would normally surprise me if someone recognized that possibility because it requires reading what I say, lol, but your are not like the closed minded mainstream apologists who shoot from the hip. The answer is that, like you said, there is not yet a quantum gravity solution. You might then grasp that according to how I characterize my hobby, if the mainstream community has not reached a consensus on quantum gravity, then I consider it fertile ground for my personal hypotheses about the quantum cause of gravity.

QG is not about consensus but it should be able to deliver the goods by explaining both QM and GR. I think "string theories" are very close to it but still falling short.

QG can be considered as "Theory of Everything".

I have also developed a theory and this theory also can be considered as "Theory of Everything" to some extent.

 

[quantum_wave]

QG is not about consensus but it should be able to deliver the goods by explaining both QM and GR. I think "string theories" are very close to it but still falling short.

QG can be considered as "Theory of Everything".

I have also developed a theory and this theory also can be considered as "Theory of Everything" to some extent.

The ToE is the elephant in the room. You obviously know the territory you get into when you bring it up in any context with "I have also developed a theory", lol. Is your theory a model or a so called model, and by that I mean are you "doing science" or are you hypothesizing similar to my hobiest activities?

Where have you revealed it?

 

[hansda]

The ToE is the elephant in the room. You obviously know the territory you get into when you bring it up in any context with "I have also developed a theory", lol. Is your theory a model or a so called model, and by that I mean are you "doing science" or are you hypothesizing similar to my hobiest activities?

This is a theory.

Where have you revealed it?

This theory can be seen here.

 

[rr6]

Space What Is It Good For---Nohting and Something( duality )

But the benefit of my so called model on this issue is that space does not have to date back to a beginning.

Hi QW, not only what you say here above is correct, but also, that, such occupied space does not have to be macro-micro infinite.

So often around this here forum--- and others ---, I see a lot of convoluted mixing and matching of the following sets, imho, there is only one possible way to mix and match them that leads to rationally logical set of conclusions;

1) infinite space/spatiality/spacial vs finite space/spatiality/spacial

2) occupied space vs non-occupied space

3) eternally occupied space existence vs a finite time of occupied space existence

4) non-existent non-occupied space vs existence of non-occupied space

5) ??? those others I have not though of or forgotten in the list above.


I think it is pretty simple concept to grasp and rationally logical support based on our observations and understanding of common accepted cosmic laws/principles.

Simple concept/scenario as follows;

.....An eternally existent infinite non-occupied space, that embraces,

an eternally existent finite occupied space that is exists as non-existent non-occupied space and non-existent occupied space, called,

mind/intellect, which is eternally complementary to occupied space, and,

to may, in some relative way, be eternally complementary to infinite non-occupied space.......

Ok so maybe that statement is a little more complex than I originally lead on that it would be. My bad..

I agree there is wonky here at sce-forums, and there is on the mark and there is comabination of both that actually come closes to truth and rationally logical concepts/scenarios.

r6

 

[quantum_wave]

This is a theory.



This theory can be seen here.

What exactly did you submit? Have you got more than "Every action has got an unique technique."?

 

[przyk]

This isn't relevant because in SR we use a constant speed of light. Einstein said repeatedly that this postulate had to be abandoned for GR.

And yet it was never abandoned. In SR the speed of light is invariant in inertial reference frames, but the coordinate speed of light can vary -- even wildly -- in non-inertial coordinate systems. Simple examples of this are the coordinate speed of light in accelerating and rotating reference frames. The invariance of c postulate holds in GR in exactly the same sense and with the same limitations and caveats as it does in SR. Nothing has changed between SR and GR as far as the speed of light is concerned. The only thing that has changed is that SR assumes the existence of globally inertial reference frames (i.e. flat spacetime) while GR relaxes this requirement (i.e. allows curved spacetime).

In fact, take that GIF you keep posting, which depicts a vaying coordinate speed of light between two light clocks at different altitudes near the Earth's surface. How do you think that's actually derived? Most of the variation depicted simply comes from working out how the coordinate speed of light varies in an accelerating reference frame according to SR, and then applying the equivalence principle. The situation would not look that way for a free-fall observer for instance, and it could even be inverted for an observer accelerating downward.

This is where you run into a problem if you try to treat the coordinate speed of light as a physical quantity and try to relate it to some idea of spatial inhomogeneity: the coordinate speed of light can vary or not vary depending on trifles like how you define coordinates or whether you're accelerating or not.

Suppose you're in a rocket in nearly empty space far away from any gravitating mass, such that the gravitational field is negligible. You do some experiments with light pulses and light clocks and find that the speed of light is invariant, just as SR says it should be. You then turn the rocket engine on and start accelerating. You repeat all your experiments and find that now, the coordinate speed of light is no longer constant, again just like SR says it should be. You furthermore find that the path light takes can bend, as depicted here for instance.

How do you explain that? Did all the space around you suddenly become inhomogeneous just because you started accelerating? Can the same region of space be homogeneous for one observer and inhomogeneous for another?

 

[quantum_wave]

Thanks for the arguments, przyk.

 

[quantum_wave]

Hi QW, not only what you say here above is correct,

Yes, the beginning is problematic. Unless you acknowledge that there were preconditions to the initial cause of observed separation of the galaxies, you are left with something from nothing or God did.

but also, that, such occupied space does not have to be macro-micro infinite.

You and I cannot get together on that particular point, but I do see why it is important in your scheme of things. Your scheme needs to have a place that goes beyond the physical, and what better place than "unoccupied space"?

So often around this here forum--- and others ---, I see a lot of convoluted mixing and matching of the following sets, imho, there is only one possible way to mix and match them that leads to rationally logical set of conclusions;

1) infinite space/spatiality/spacial vs finite space/spatiality/spacial

2) occupied space vs non-occupied space

3) eternally occupied space existence vs a finite time of occupied space existence

4) non-existent non-occupied space vs existence of non-occupied space

5) ??? those others I have not though of or forgotten in the list above.

A good and thought provoking list.

I think it is pretty simple concept to grasp and rationally logical support based on our observations and understanding of common accepted cosmic laws/principles.

Simple concept/scenario as follows;

.....An eternally existent infinite non-occupied space, that embraces,

an eternally existent finite occupied space that is exists as non-existent non-occupied space and non-existent occupied space, called,

mind/intellect, which is eternally complementary to occupied space, and,

to may, in some relative way, be eternally complementary to infinite non-occupied space.......

Ok so maybe that statement is a little more complex than I originally lead on that it would be. My bad..

Did you want to link to your thread? Feel free.

I agree there is wonky here at sce-forums, and there is on the mark and there is comabination of both that actually come closes to truth and rationally logical concepts/scenarios.

I guess that is true, but "on the mark" and "comes close to the truth" are quite subjective.

 

[brucep]

And yet it was never abandoned. In SR the speed of light is invariant in inertial reference frames, but the coordinate speed of light can vary -- even wildly -- in non-inertial coordinate systems. Simple examples of this are the coordinate speed of light in accelerating and rotating reference frames. The invariance of c postulate holds in GR in exactly the same sense and with the same limitations and caveats as it does in SR. Nothing has changed between SR and GR as far as the speed of light is concerned. The only thing that has changed is that SR assumes the existence of globally inertial reference frames (i.e. flat spacetime) while GR relaxes this requirement (i.e. allows curved spacetime).

In fact, take that GIF you keep posting, which depicts a vaying coordinate speed of light between two light clocks at different altitudes near the Earth's surface. How do you think that's actually derived? Most of the variation depicted simply comes from working out how the coordinate speed of light varies in an accelerating reference frame according to SR, and then applying the equivalence principle. The situation would not look that way for a free-fall observer for instance, and it could even be inverted for an observer accelerating downward.

This is where you run into a problem if you try to treat the coordinate speed of light as a physical quantity and try to relate it to some idea of spatial inhomogeneity: the coordinate speed of light can vary or not vary depending on trifles like how you define coordinates or whether you're accelerating or not.

Suppose you're in a rocket in nearly empty space far away from any gravitating mass, such that the gravitational field is negligible. You do some experiments with light pulses and light clocks and find that the speed of light is invariant, just as SR says it should be. You then turn the rocket engine on and start accelerating. You repeat all your experiments and find that now, the coordinate speed of light is no longer constant, again just like SR says it should be. You furthermore find that the path light takes can bend, as depicted here for instance.

How do you explain that? Did all the space around you suddenly become inhomogeneous just because you started accelerating? Can the same region of space be homogeneous for one observer and inhomogeneous for another?

The REMOTE coordinate speed of light is frame dependent and can vary. The LOCAL coordinate speed of light is an invariant. Farsight probably thinks there's only the coordinate speed of light. That frame doesn't exist.

dr/dt = 1 Local coordinate speed of light. Invariant.

dr/dt = 1-2M/r The remote coordinate speed of light. Frame dependent.

We use local coordinate speed for light because there is no local proper frame for light. Not understanding the difference from where these measurement are made are the main reason why so much Farsight type nonsense is proliferated in these public forums. IE: not understanding the difference between frame invariant and frame dependent. Completely confused by reference frames. It's comical, but very annoying, when Farsight says Einstein had to abandon the notion that c is invariant so GR could evaluate natural phenomena from remote coordinates. It just screams of ignorance.

 

[Undefined]

...when Farsight says Einstein had to abandon the notion that c is invariant so GR could evaluate natural phenomena from remote coordinates. It just screams of ignorance.

With respect, brucep, when did Farsight say that? All I have read him say is that "the seconds are not the same", implying the 'c' invariance is a function of the differing timerate states in differing frame states. So, my naive reading of his comments so far tells me he does not argue about 'invariant c', but argues for the varying time (second) used to arrive at that agreed 'invariant c' between the differing frame states? He has just said as much in his reply to Tach, hasn't he?

 

[przyk]

The REMOTE coordinate speed of light is frame dependent and can vary. The LOCAL coordinate speed of light is an invariant.

Depends on what you mean by "local" coordinate speed. It may be common to use coordinate systems in which the metric expression coincides with the Minkowski metric at a certain point. This is true for the construction of accelerating and rotating reference frames (around the point of acceleration or the centre of rotation) as well as the Schwarzschild metric (at infinity). But it's a matter of choice and not a requirement to do it this way.

Focusing too much on the coordinate speed of light -- the way Farsight does -- is problematic because coordinate-dependent quantities are generally only as meaningful as the coordinates they are defined in terms of, and coordinates by default have no required physical significance in GR.

 

[Undefined]

And yet it was never abandoned. In SR the speed of light is invariant in inertial reference frames, but the coordinate speed of light can vary -- even wildly -- in non-inertial coordinate systems. Simple examples of this are the coordinate speed of light in accelerating and rotating reference frames. The invariance of c postulate holds in GR in exactly the same sense and with the same limitations and caveats as it does in SR. Nothing has changed between SR and GR as far as the speed of light is concerned. The only thing that has changed is that SR assumes the existence of globally inertial reference frames (i.e. flat spacetime) while GR relaxes this requirement (i.e. allows curved spacetime).

In fact, take that GIF you keep posting, which depicts a vaying coordinate speed of light between two light clocks at different altitudes near the Earth's surface. How do you think that's actually derived? Most of the variation depicted simply comes from working out how the coordinate speed of light varies in an accelerating reference frame according to SR, and then applying the equivalence principle. The situation would not look that way for a free-fall observer for instance, and it could even be inverted for an observer accelerating downward.

This is where you run into a problem if you try to treat the coordinate speed of light as a physical quantity and try to relate it to some idea of spatial inhomogeneity: the coordinate speed of light can vary or not vary depending on trifles like how you define coordinates or whether you're accelerating or not.

Suppose you're in a rocket in nearly empty space far away from any gravitating mass, such that the gravitational field is negligible. You do some experiments with light pulses and light clocks and find that the speed of light is invariant, just as SR says it should be. You then turn the rocket engine on and start accelerating. You repeat all your experiments and find that now, the coordinate speed of light is no longer constant, again just like SR says it should be. You furthermore find that the path light takes can bend, as depicted here for instance.

How do you explain that? Did all the space around you suddenly become inhomogeneous just because you started accelerating? Can the same region of space be homogeneous for one observer and inhomogeneous for another?

Sorry, I have to be brief.

Please excuse my naive questions, przyk....

How do closely co-located respective observers of the light clocks in each of two positions (first at lower and then at upper 'altitude' in a gravity well) affect what he sees of the light motion between two closely-spaced parallel mirrors?

And what does the observer have to do with the fact that the clock tick absolute number counts will differ irrespective of what co-ordinate system we define/use to "calculate" the 'invariant c' speed of the light pulses?

Thanks, przyk. Back tomorrow.

 

[przyk]

With respect, brucep, when did Farsight say that?

Nobody, including Farsight, knows what Farsight is saying in any detail. His explanations are simply far too superficial and vague for anyone to get a useful handle on them. (If you disagree, try calculating GR's prediction for gravitational time dilation, redshift, the Mercury perihelion advance, or the precession of orbiting gyroscopes purely from Farsight's posts. I certainly don't know how to do that, and neither does Farsight.)

 

[przyk]

How do closely co-located respective observers of the light clocks in each of two positions (first at lower and then at upper 'altitude' in a gravity well) affect what he sees of the light motion between two closely-spaced parallel mirrors?

I was only considering one observer in the rocket. This observer sits in a single place and needs to devise some scheme for remotely measuring the coordinate speed of light in different places throughout the rocket according to some locally defined measure of distance and time.

The varying coordinate speed of light in accelerating reference frames is based on a fairly standard way of defining an accelerating reference frame. Basically, to define a reference frame, you need to define three things: 1) what your reference measure of time is, 2) what your measure of distance is, and 3) how you define simultaneity (i.e. when do you consider that two distant events are happening "at the same time"?). For accelerating reference frames, these are 1) the accelerating observer's accumulated proper time, 2) the instantaneous inertial rest frame's distance measure at that time and 3) the instantaneous inertial rest frame's definition of simultaneity at that time.

Requiring experimental apparatus on an accelerating rocket to actually make measurements consistent with that definition can get contrived quite quickly. Even there, the only thing measuring a variable coordinate speed of light would really prove is that your experimental apparatus was doing what you'd specifically calibrated it to do. But it's Farsight who keeps going on about the coordinate speed of light, so this is Farsight's problem to worry about if he insists on treating the coordinate speed of light like a physical quantity. Otherwise it isn't important for the point I was making.

And what does the observer have to do with the fact that the clock tick absolute number counts will differ irrespective of what co-ordinate system we define/use to "calculate" the 'invariant c' speed of the light pulses?

It only really makes sense to compare the "absolute number of counts" accumulated by two clocks if they're located together in the same place and at the same time. That's the only situation where you get a definite and unique result.

If you compare two clocks some distance apart from one another, then the relative rate at which one clock advances compared to the other depends on how you're making the comparison between the two. More precisely, it depends on how you define simultaneity, i.e. how do you decide what time one clock is displaying "when" the other clock is displaying some particular time? The reason time dilation factors and such are frame dependent in SR is that different observers in different states of motion generally disagree on what "when" means. (And this only gets worse in GR.)

 

[Undefined]

Hi przyk. Thanks for your prompt responses. Just came in again to check a PM, but will stay long enough to briefly reply to yours while I am here...

Nobody, including Farsight, knows what Farsight is saying in any detail. His explanations are simply far too superficial and vague for anyone to get a useful handle on them. (If you disagree, try calculating GR's prediction for gravitational time dilation, redshift, the Mercury perihelion advance, or the precession of orbiting gyroscopes purely from Farsight's posts. I certainly don't know how to do that, and neither does Farsight.)

I naively feel that before making accusations/criticisms, the onus is on his critic/accuser in this instance to show he undertand what Farsight actually said, especially when claiming the oposite of what Farsight just said to Tach and should have been read before posting, like in this instance.

Farsight just said in reply to Tach that the invariant c is due to "different seconds" used for arriving at that invariant c result. I read that naively as not arguing against invariant c, but merely explaining why the 'c' is an calculated as an invariant 'c' (hence my polite request to brucep to show where Farsight argued against calculated 'invariant c').

I was only considering one observer in the rocket. This observer sits in a single place and needs to devise some scheme for remotely measuring the coordinate speed of light in different places throughout the rocket according to some locally defined measure of distance and time.

The varying coordinate speed of light in accelerating reference frames is based on a fairly standard way of defining an accelerating reference frame. Basically, to define a reference frame, you need to define three things: 1) what your reference measure of time is, 2) what your measure of distance is, and 3) how you define simultaneity (i.e. when do you consider that two distant events are happening "at the same time"?). For accelerating reference frames, these are 1) the accelerating observer's accumulated proper time, 2) the instantaneous inertial rest frame's distance measure at that time and 3) the instantaneous inertial rest frame's definition of simultaneity at that time.

Requiring experimental apparatus on an accelerating rocket to actually make measurements consistent with that definition can get contrived quite quickly. Even there, the only thing measuring a variable coordinate speed of light would really prove is that your experimental apparatus was doing what you'd specifically calibrated it to do. But it's Farsight who keeps going on about the coordinate speed of light, so this is Farsight's problem to worry about if he insists on treating the coordinate speed of light like a physical quantity. Otherwise it isn't important for the point I was making.




It only really makes sense to compare the "absolute number of counts" accumulated by two clocks if they're located together in the same place and at the same time. That's the only situation where you get a definite and unique result.

If you compare two clocks some distance apart from one another, then the relative rate at which one clock advances compared to the other depends on how you're making the comparison between the two. More precisely, it depends on how you define simultaneity, i.e. how do you decide what time one clock is displaying "when" the other clock is displaying some particular time? The reason time dilation factors and such are frame dependent in SR is that different observers in different states of motion generally disagree on what "when" means. (And this only gets worse in GR.)

Yes, I naively understood all that already, przyk (Pete's threads dealing/discussing that very aspect of simultaneity etc covered that exhaustively).

In the case of gedanken, it is not a problem because Einstein already defines and assumes simultaneity etc.

In the case of real world experiment, I use three identical light clocks initially co-located at an intermediate location halfway between the top and bottom of a tall tower, then move TWO of the clocks at same speed, one to the top and one to the bottom of the tower. This way we minimize any extraneous SR variables due to motion and treat only the actual changed positions in the GR gravity well. To remove even more extraneous variables we could do the experiment on a non/minimally-rotating planet/body (such as our Moon?).

In any case, I naively examine the essentials. The TWO clocks tick "absolute number counts" do differ between them and with the non-moved clock when both moved clocks are moved back at same speed to initial co-located positions halfway between top and bottom of tower.

No amount of arbitrary reasons, coordinate choices etc will remove the essential observable that the difference occurs because of different positions (altitude) in a gravity well. Yes?

Have to go! Thanks again for your polite response, przyk. Back tomorrow.