Consider a solenoid attached to a very unyielding shaft 100 feet long that did not stretch or compress (hypothetical). The instant the solenoid shaftr moved within the magnetic field, the other end of the shaft would move. It would move BEFORE a light signal announcing the energizing of the solenoid reached an observer at the other end. The shart would move BEFORE the light flashed on.

Another example is a wheel. When you rotate the axil the outside of the wheel moves instantly. It does not wait for an speed of light information signal, it moves instantly.

So consider when you move the outside of a wheel from one end, the other side of the wheel moves at the same time. Not later, but at the same time. You are pulling one side of the wheel toward you and the other side away and the opposite end of the wheel moves exactly at the same time as the section you have just moved.

Now imagine a carousel 100 ft in diameter. you move it from one end and you are moving the other end without delay. It is actually moving simultaneously as you move your end. An observer at the other end is separated from you by a femtosecond or whatever but the action is so, .

So take the outside of a wheel and turn it into a loop and stretch the loop out into a giant ellipse. and put a CCD target attached to the far end of the loop and fire a laser at the target at the same instant you fire a solenoid that shifts the loop on your end.

Will you hit the target? Or will it have already shifted by the time the light signal reached it?

Regards, TAR

Sort of like that row of steel balls hanging from a beam. You swing a ball into one end of the row and the last ball in the chain pops out.

Axel

1 minute ago, tar said:

Consider a solenoid attached to a very unyielding shaft 100 feet long that did not stretch or compress (hypothetical). The instant the solenoid shaftr moved within the magnetic field, the other end of the shaft would move. It would move BEFORE a light signal announcing the energizing of the solenoid reached an observer at the other end. The shart would move BEFORE the light flashed on.

Another example is a wheel. When you rotate the axil the outside of the wheel moves instantly. It does not wait for an speed of light information signal, it moves instantly.

So consider when you move the outside of a wheel from one end, the other side of the wheel moves at the same time. Not later, but at the same time. You are pulling one side of the wheel toward you and the other side away and the opposite end of the wheel moves exactly at the same time as the section you have just moved.

Now imagine a carousel 100 ft in diameter. you move it from one end and you are moving the other end without delay. It is actually moving simultaneously as you move your end. An observer at the other end is separated from you by a femtosecond or whatever but the action is so, .

So take the outside of a wheel and turn it into a loop and stretch the loop out into a giant ellipse. and put a CCD target attached to the far end of the loop and fire a laser at the target at the same instant you fire a solenoid that shifts the loop on your end.

Will you hit the target? Or will it have already shifted by the time the light signal reached it?

Regards, TAR

Sort of like that row of steel balls hanging from a beam. You swing a ball into one end of the row and the last ball in the chain pops out.

You have to be careful talking about rigid bodies when it comes to relativity.

If a rigid pole is long enough then one end will not instantly move because you apply a force at the other.

It will move according to the molecular forces along the mass which is not instant.

Speed of sound in the medium the force is applied to, so about 17,000 mph in metal (I think don't hang me on that) so that is nowhere near speed of light and even less instantaneous.

30 minutes ago, tar said:

It would move BEFORE a light signal announcing the energizing of the solenoid reached an observer at the other end

No it would not.
Information, even mechanical, is limited by the speed of light.

And 'spooky action at a distance' involves action caused by unconnected agents, such as how the gravity of one body can affect another body without anything connecting/transferring between them.

Is there something you wish to ask, before stating absurdities ?

Edited September 5Sep 5 by MigL

pinball1970, so I figured as much, that it would come down to the speed of the electromagnet "wave" or the speed of the compression or rarefaction wave going though the structure connecting the two distant points, but suppose something about the universe operates on Pneumatic type principles where the force applied on one pitton is immediately "felt" on all the walls of the tubes between and on the piston at the other end of the system.

I am thinking that the way the universe works is not so much a serial cause and effect thing but more of a parallel cause an effect thing were things are happening at the same time in different places due to the same initial cause. Like setting up a line of dominoes to fall into TWO lines of dominoes and each of those lines set up to fall into two lines. You could knock over one domino HERE and the last domino in 64 rows will fall at the exact same moment, even though the ends of the two outside lines are separated by space that a light signal would need time to cross.

Regards, TAR

So the solenoid and loop and wheel ideas are out, but what about the parallel cause and effect. The idea of simultaneity has to mean something. I still have a problem with the lighting strike at the end of the train observed from the side of the track and from a passenger on the train. Why is the lightning strike considered instantaneous. Instantaneous in what way if something cannot happen at the same time for distant observers, what does happening at the same time mean? How can Einstein use a concept as a premise that he disproves as a conclusion? I have read and reread his Train example many many times and I cannot figure out how and why he considers the lightning strike instantaneous.

in the train thought experiments is the front of the train moving at the same time as the back end of the train?

1 minute ago, tar said:

pinball1970, so I figured as much, that it would come down to the speed of the electromagnet "wave" or the speed of the compression or rarefaction wave going though the structure connecting the two distant points, but suppose something about the universe operates on Pneumatic type principles where the force applied on one pitton is immediately "felt" on all the walls of the tubes between and on the piston at the other end of the system.

I am thinking that the way the universe works is not so much a serial cause and effect thing but more of a parallel cause an effect thing were things are happening at the same time in different places due to the same initial cause. Like setting up a line of dominoes to fall into TWO lines of dominoes and each of those lines set up to fall into two lines. You could knock over one domino HERE and the last domino in 64 rows will fall at the exact same moment, even though the ends of the two outside lines are separated by space that a light signal would need time to cross.

Regards, TAR

So the solenoid and loop and wheel ideas are out, but what about the parallel cause and effect. The idea of simultaneity has to mean something. I still have a problem with the lighting strike at the end of the train observed from the side of the track and from a passenger on the train. Why is the lightning strike considered instantaneous. Instantaneous in what way if something cannot happen at the same time for distant observers, what does happening at the same time mean? How can Einstein use a concept as a premise that he disproves as a conclusion? I have read and reread his Train example many many times and I cannot figure out how and why he considers the lightning strike instantaneous.

This is all over the place. There is no "parallel cause and effect". As already stated by @MigL it is a principle of relativity that information, however transmitted, cannot be sent faster than c. So this idea of yours is wrong, at least wrong as far as modern physics is concerned, so wrong to the best of our knowledge.

By the way a "pneumatic type" transmission mechanism take time to react, as pressure in a gas takes time to build up and a fast change in pressure at one end of a pneumatic tube will produce a pressure wave that will travel down the tube at quite a modest speed.

You then glitch and start burbling about lightning strikes on trains and Einstein. What is all that about?

7 minutes ago, tar said:

The idea of simultaneity has to mean something.

It does. It means it happens at the same time in your frame.

7 minutes ago, tar said:

I still have a problem with the lighting strike at the end of the train observed from the side of the track and from a passenger on the train. Why is the lightning strike considered instantaneous.

Simple. It’s not instantaneous.

The strikes are simultaneous because they happen at the same time.

7 minutes ago, tar said:

Instantaneous in what way if something cannot happen at the same time for distant observers, what does happening at the same time mean? How can Einstein use a concept as a premise that he disproves as a conclusion? I have read and reread his Train example many many times and I cannot figure out how and why he considers the lightning strike instantaneous.

Happens at the same time means the clock readings are the same. You can synchronize (ideal) clocks only in the same frame of reference.

What Einstein showed was that simultaneity is frame-dependent

9 minutes ago, tar said:

How can Einstein use a concept as a premise that he disproves as a conclusion? I have read and reread his Train example many many times and I cannot figure out how and why he considers the lightning strike instantaneous.

As per our PMs

Every different observer carries their own different perspective, shaped by different, and unique, trajectories through space-time; it is a tenet of Relativity.

13 minutes ago, exchemist said:

This is all over the place. There is no "parallel cause and effect". As already stated by @MigL it is a principle of relativity that information, however transmitted, cannot be sent faster than c. So this idea of yours is wrong, at least wrong as far as modern physics is concerned, so wrong to the best of our knowledge.

By the way a "pneumatic type" transmission mechanism take time to react, as pressure in a gas takes time to build up and a fast change in pressure at one end of a pneumatic tube will produce a pressure wave that will travel down the tube at quite a modest speed.

You then glitch and start burbling about lightning strikes on trains and Einstein. What is all that about?

14 minutes ago, exchemist said:

This is all over the place. There is no "parallel cause and effect". As already stated by @MigL it is a principle of relativity that information, however transmitted, cannot be sent faster than c. So this idea of yours is wrong, at least wrong as far as modern physics is concerned, so wrong to the best of our knowledge.

By the way a "pneumatic type" transmission mechanism take time to react, as pressure in a gas takes time to build up and a fast change in pressure at one end of a pneumatic tube will produce a pressure wave that will travel down the tube at quite a modest speed.

You then glitch and start burbling about lightning strikes on trains and Einstein. What is all that about?

I was voicing a concern I have had for many years that the whole theory of relativity is based on assumptions of instantaneous events and the term instantaneous has no meaning within the theory.Two distant observers cannot witness the same moment, by defintion.

26 minutes ago, swansont said:

It does. It means it happens at the same time in your frame.

Simple. It’s not instantaneous.

The strikes are simultaneous because they happen at the same time.

Happens at the same time means the clock readings are the same. You can synchronize (ideal) clocks only in the same frame of reference.

What Einstein showed was that simultaneity is frame-dependent

bu

4 minutes ago, tar said:

I was voicing a concern I have had for many years that the whole theory of relativity is based on assumptions of instantaneous events and the term instantaneous has no meaning within the theory.Two distant observers cannot witness the same moment, by defintion.

4 minutes ago, tar said:

I was voicing a concern I have had for many years that the whole theory of relativity is based on assumptions of instantaneous events and the term instantaneous has no meaning within the theory.Two distant observers cannot witness the same moment, by defintion.

25 minutes ago, MigL said:

As per our PMs

Every different observer carries their own different perspective, shaped by different, and unique, trajectories through space-time; it is a tenet of Relativity.

Understood, but the reading on a clock is also dependent on your distance from the clock.. If you are a light femtosecond away from a clock you will see AWAYS, the wrong time. The clock always reads the time it was a femtosecond ago even though you are in the same acceleration frame as the clock.

Regards, TAR

53 minutes ago, tar said:

I cannot figure out how and why he considers the lightning strike instantaneous.

This seems to be the only actual question here.

The point about the Einstein lightening strike is that it marks both the train and the platform with a visible, permanent mark that can be seen and measured at a later time.

The act of the strike in such a small space is considered instantaneous and appears in both frames of reference.

Do you understand what the two frames of reference are ?

Edit

The crux of 'spooky action at a distance' is the diostance bit.

You need to separate the speed the action is transmitted across the distance from the distance itself an is irrelevant to the problem of how something influences something else which is some distance away ( some may be large or small)

Edited September 5Sep 5 by studiot

33 minutes ago, MigL said:

As per our PMs

Every different observer carries their own different perspective, shaped by different, and unique, trajectories through space-time; it is a tenet of Relativity.

13 minutes ago, tar said:

I was voicing a concern I have had for many years that the whole theory of relativity is based on assumptions of instantaneous events and the term instantaneous has no meaning within the theory.Two distant observers cannot witness the same moment, by defintion.

bu

Understood, but the reading on a clock is also dependent on your distance from the clock.. If you are a light femtosecond away from a clock you will see AWAYS, the wrong time. The clock always reads the time it was a femtosecond ago even though you are in the same acceleration frame as the clock.

Regards, TAR

13 minutes ago, tar said:

I was voicing a concern I have had for many years that the whole theory of relativity is based on assumptions of instantaneous events and the term instantaneous has no meaning within the theory.Two distant observers cannot witness the same moment, by defintion.

bu

Understood, but the reading on a clock is also dependent on your distance from the clock.. If you are a light femtosecond away from a clock you will see AWAYS, the wrong time. The clock always reads the time it was a femtosecond ago even though you are in the same acceleration frame as the clock.

Regards, TAR

Well in the theory, how big is an observer allowed to be, and how is the distance between their eye and their brain accounted for. What "instant" are we counting as now?

I am on about this because I think the key in unifying general and special relativity is in accounting for the size of the observer and the position of the observer relative to the event. Certain things on the QED level happen in a very tiny space, all within your reach whereas things happening on distant stars are happening WAY out of your reach. So an equation that would account for things happening on both scales would have to include the size and position of the observer and the size of a moment, that is an indication of what you are considering happening at the same time, must be included in the equation.

Light signals take 22 minutes to get from Mars to Earth when Mars is on the other side of the Sun from Earth. How do we define the "same" moment occurring on Mars, as on the Earth?

4 minutes ago, studiot said:

This seems to be the only actual question here.

The point about the Einstein lightening strike is that it marks both the train and the platform with a visible, permanent mark that can be seen and measured at a later time.

The act of the strike in such a small space is considered instantaneous and appears in both frames of reference.

Do you understand what the two frames of reference are ?

I thought it was a stationary observer on the side of the tracks and a moving observer on the train?

my problem is Einstein introduces a third imaginary observer that sees the lightning strike happening in an instant. He does this when he proposes the lighting strike happens only once simultaneously for both observers.

We talked about this years ago. The difference in clock tics between a stationary observer and a moving observer can be accounted for with simple redshift and blueshift as the observer moves away from the stationary clock or toward it. No time dilation or foreshortening of objects is required.

Besides, relativistic speeds are not obtainable, they take too much energy to achieve and no human could survive the acceleration and deceleration required to complete the experiment, much less survive the gamma rays he is traveling into as all the radio waves and visible light coming from the direction he is traveling are blue shifted into harmful energy levels.

43 minutes ago, tar said:

Understood, but the reading on a clock is also dependent on your distance from the clock.. If you are a light femtosecond away from a clock you will see AWAYS, the wrong time. The clock always reads the time it was a femtosecond ago even though you are in the same acceleration frame as the clock.

You’re not in an acceleration frame (SR works in u]inertial frames), and the light-travel time is something you account for.

It’s a lot harder to understand when you don’t bother learn the various elements and skip directly to the end.

26 minutes ago, studiot said:

The point about the Einstein lightening strike is that it marks both the train and the platform with a visible, permanent mark that can be seen and measured at a later time.

The act of the strike in such a small space is considered instantaneous and appears in both frames of reference.

It’s not even that. You are equidistant from the two landing points so the light travel time is equal. Thus seeing them at the same time means they are simultaneous.

21 minutes ago, studiot said:

This seems to be the only actual question here.

The point about the Einstein lightening strike is that it marks both the train and the platform with a visible, permanent mark that can be seen and measured at a later time.

The act of the strike in such a small space is considered instantaneous and appears in both frames of reference.

Do you understand what the two frames of reference are ?

21 minutes ago, studiot said:

This seems to be the only actual question here.

The point about the Einstein lightening strike is that it marks both the train and the platform with a visible, permanent mark that can be seen and measured at a later time.

The act of the strike in such a small space is considered instantaneous and appears in both frames of reference.

Do you understand what the two frames of reference are ?

so neither observer is seeing the strike at T=0. They both see it at a later time. To treat T plus one for both observers as the same time to compare their obsevations is again introducing a third observer that views both observers at the "same" time. Instantaneously. In many of the relativity equations I have seen theire seems to be this third observer that can view both frames at the same time. Not sure this is possible, at least not in the manner presented. Both frames can be viewed by a third observer but a time and distance correction has to be applied to reestablish continuity between the two observed frames. Everything that happens in the Universe happens only once and in a certain relationship with the rest of the Universe. Different observers can order events differently but there remains on "actual" order in which the events occurred, witness by the third imaginary observer with the ability to make the proper transforms between the two observers to come up with the "actual" order of events..

24 minutes ago, tar said:

I am on about this because I think the key in unifying general and special relativity is in accounting for the size of the observer and the position of the observer relative to the event. Certain things on the QED level happen in a very tiny space, all within your reach whereas things happening on distant stars are happening WAY out of your reach. So an equation that would account for things happening on both scales would have to include the size and position of the observer and the size of a moment, that is an indication of what you are considering happening at the same time, must be included in the equation.

You don’t include things that don’t affect the physics. Size and position of an observer are experimental details.

24 minutes ago, tar said:

Light signals take 22 minutes to get from Mars to Earth when Mars is on the other side of the Sun from Earth. How do we define the "same" moment occurring on Mars, as on the Earth?

Assuming they’re in the same inertial frame, you account for the light travel time.

15 minutes ago, tar said:

Everything that happens in the Universe happens only once and in a certain relationship with the rest of the Universe. Different observers can order events differently but there remains on "actual" order in which the events occurred

Yes, it may happen only once, but the relationship with the rest of the universe differs with the frames of reference of different observers in the universe.
There is no absolute frame of reference, observer, or 'now'.
If you won't believe me, ask the only absolute observer that I know of, God; let me know what He tells you.

11 minutes ago, tar said:

so neither observer is seeing the strike at T=0.

T=0 is an arbitrary designation, and you don’t have to use numbers to analyze the concept. Just that the time is the same.

11 minutes ago, tar said:

They both see it at a later time. To treat T plus one for both observers as the same time to compare their obsevations is again introducing a third observer that views both observers at the "same" time.

No. You’re overcomplicating the situation.

11 minutes ago, tar said:

Instantaneously. In many of the relativity equations I have seen theire seems to be this third observer that can view both frames at the same time.

That the information is being conveyed to you, the reader, does not create another observer.

2 hours ago, tar said:

I was voicing a concern I have had for many years that the whole theory of relativity is based on assumptions of instantaneous events and the term instantaneous has no meaning within the theory.Two distant observers cannot witness the same moment, by defintion.

Regards, TAR

OK, evidently there haas been some correspondence about lightning and Einstein outside the thread, that I was not party to. I'll leave to the others who seem to understand what you are referring to.

3 hours ago, tar said:

so neither observer is seeing the strike at T=0. They both see it at a later time. To treat T plus one for both observers as the same time to compare their obsevations is again introducing a third observer that views both observers at the "same" time. Instantaneously. In many of the relativity equations I have seen theire seems to be this third observer that can view both frames at the same time. Not sure this is possible, at least not in the manner presented. Both frames can be viewed by a third observer but a time and distance correction has to be applied to reestablish continuity between the two observed frames. Everything that happens in the Universe happens only once and in a certain relationship with the rest of the Universe. Different observers can order events differently but there remains on "actual" order in which the events occurred, witness by the third imaginary observer with the ability to make the proper transforms between the two observers to come up with the "actual" order of events..

I must admit that it is a long time since I last looked at Einstein's train and lightning though experiments and I was thinking about the length contraction one.

I no longer have the original text of these experiments, but I have found a reliable explanation online here.

https://www.vicphysics.org/documents/teachers/unit3/EinsteinsTrainGedanken.pdf

Note the authors' comment that there are a lot of versions about, some quite misinformed.

No there is no third, fourth or what ever observer involved and there are only two frames, the frame of the train and the frame of the platform.

The referenced article explains quite well what you may be thinking of as a third observer as the point of view that the train is standing still and the platform is moving past it.

However, as far as I can see all this is entirely off topic and you have made no response at all to my comments on the actual topic of this thread viz spooky action at a distance.

I suggest the relativity issue be further discussed in its own thread as it is entirely off topic to action-at-a-distance, spooky or otherwise.

5 hours ago, tar said:

I was voicing a concern I have had for many years that the whole theory of relativity is based on assumptions of instantaneous events and the term instantaneous has no meaning within the theory.Two distant observers cannot witness the same moment, by defintion.

Your concern is based on your misunderstanding of something, and that’s got to be the assumption until you actually present the train paradox narrative that says anything about “instantaneous” or “now” or distant observers “witnessing the same moment”

AFAICT you’re confused by your own strawman

6 hours ago, tar said:

The difference in clock tics between a stationary observer and a moving observer can be accounted for with simple redshift and blueshift as the observer moves away from the stationary clock or toward it. No time dilation or foreshortening of objects is required.

Time dilation is already built into the formula for the redshift and blueshift of light.

Indeed, the twin paradox can be explained entirely in terms of the redshift and blueshift that is observed by the two twins. This also provides a clear understanding of the asymmetry between the travelling twin and the stay-at-home twin.

Edited September 6Sep 6 by KJW

7 hours ago, tar said:

We talked about this years ago. The difference in clock tics between a stationary observer and a moving observer can be accounted for with simple redshift and blueshift as the observer moves away from the stationary clock or toward it. No time dilation or foreshortening of objects is required.

You can send a signal stating what time your clock read that won’t depend on shifts. “When I observed the event my clock read 12:07” sent by morse code, for example.

7 hours ago, tar said:

Besides, relativistic speeds are not obtainable, they take too much energy to achieve and no human could survive the acceleration and deceleration required to complete the experiment, much less survive the gamma rays he is traveling into as all the radio waves and visible light coming from the direction he is traveling are blue shifted into harmful energy levels.

It doesn’t it have to be a human undergoing the acceleration; it just happens to be people in certain thought experiments. This isn’t a (intellectually) serious objection. When we do actual tests we don’t use people. When making measurements, people are quite imprecise. That’s why we use various lab equipment devices/tools.

But people can and do travel at relativistic speeds. Speed is relative, so you can accelerate anything, and a human will have some speed relative to it. If relativistic means “able to measure an effect of relativity” (typically time dilation, since it’s the easiest to measure) we even accelerate people to and from these speeds.

20 hours ago, MigL said:

Information, even mechanical, is limited by the speed of light.

The absolute limit, yes. But you could go lower, by stating that mechanical information never can go faster than the speed of sound in the material we are working with. Maybe it helps tar to understand it... maybe not.

18 hours ago, MigL said:

Yes, it may happen only once, but the relationship with the rest of the universe differs with the frames of reference of different observers in the universe.
There is no absolute frame of reference, observer, or 'now'.
If you won't believe me, ask the only absolute observer that I know of, God; let me know what He tells you.

You can't prove a negative. You say there is no absolute frame of reference, but you could only say that if you were assuming one cannot have a point of reference. Human existence proves the opposite, there IS a point of reference available, that is an observer, a human observer on Earth. So you say there is NO absolute frame of reference which now becomes an argument against God. And you take on the perspective of God and replace him with the lightcone and E=mc squared and curved space and dark energy and dark matter, anti particles, and nuetrinos and predictions that the universe will end in 300B years, as if you can contain the Universe, all of space and time in your mind, in an equation.

Well I have been around for 71 years. I have taken math and physics courses, I have read books on QED and relativity. I could not find my book where Einstein explained the train and lightning relativity thing, so I don't have his words to use in this discussion at the moment but I did fine Hermann Bond's Relativity and Common Sense, A New Approach to Einstein, Copyrighted in 1962 and 1964. I read it then and am looking through it now. Reading on the internet, various articles about relativity, I see a lot of misinterpretations and conclusions being drawn about what Relativity is, what it shows and what it might "predict". I will have to reread the book, but a general idea I get, related to this thread is it is important to apply common sense to the equations and not let the equations take you into dreamland where science is not applicable, and hypothesis can not be tested.

My proposal is you accept the fact that the universe is immense and long lived and complicated yet intertwined in a manner that is WAY beyond our comprehension and that you and I are in and of this thing.

What you and I then worship of it is a personal choice. Whether you disbelieve in a creator or are agnostic about it, or believe there is a creator is really immaterial,. The reality is, there is a Universe, and it is too immense and long lived and intertwined to hold within our tiny collection of nerves and synapses and folds and cortexes. We can contain a model of the thing, but we cannot contain the thing. When we perform a calculation, we are performing a manipulation of model. Applying transforms to bring one analogy into another context. In essence we are taking a god like perspective and manipulating the universe or our analog model of it, within our brains.

I say this gives us the ability to take a god like perspective. You don't have to posit God to take this perspective. You just have to take it. We do it all the time when we put hypothetical observers on planets lys away and move them around at "relativistic" speeds. But here is where common sense comes in. What you can do with your transform is limited. You had to simplify the problem in order to get an equation you could integrate or find the derivative or add together or square or cube or apply your transforming equation to. My common sense approach says that when you simplify in this manner, you are absolutely going to be dropping out elements of reality that MAY be crucial to describing reality correctly. And just because the equation works in your head, doe not mean reality will follow the equation. Might in a general sense. But if you are calculating how much milk you are going to get, you cannot have any 1/2 cows in the equation.

What this thread is about is Spooky Action at a distance. Something Einstein came up with i believe when thinking about entangled particles. This action at a distance breaks causality and breaks the light speed limit. So I started the thread to speculate on what mechanism might be present to allow for spooky action at a distance, that would NOT break causality or the speed limit. Such as the domino thing where the same cause can spread out and create effects in an ever increasing spherical shell. To envision this shell you have to take on a godlike perspective and "see" the shell expanding.

Regards, TAR

18 hours ago, exchemist said:

OK, evidently there haas been some correspondence about lightning and Einstein outside the thread, that I was not party to. I'll leave to the others who seem to understand what you are referring to.

Exchemist,

I apologize. I pulled it in out of the blue. It was from a book I read where Einstein is describing the train and lightning strikes observed from the moving train and from a stationary observer on the side of the tracks.

I can't find the book. So I really can't refer to it properly. I am 71 and my memory is somewhat challenged. So although it is central to the discussion of the theory of relativity because the assumptions made during that explanation ARE the assumptions of the theory, I will have to drop the line of questioning because I can't locate the witness.

Regards, TAR

11 minutes ago, tar said:

I say this gives us the ability to take a god like perspective. You don't have to posit God to take this perspective. You just have to take it.

That was sarcasm, as I don't believe in imaginary beings that can observe the universe from 'outside'.

Any observation you can make, I can give another which differs in time and location, because it is made from a different frame.
And it, and all others, will be just as valid.

16 minutes ago, tar said:

that the universe is immense and long lived and complicated yet intertwined in a manner that is WAY beyond our comprehension

If you want to use that 'excuse' for your failure to comprehend relativity, that's fine.
The rest of us don't have that problem.

16 hours ago, studiot said:

I must admit that it is a long time since I last looked at Einstein's train and lightning though experiments and I was thinking about the length contraction one.

I no longer have the original text of these experiments, but I have found a reliable explanation online here.

https://www.vicphysics.org/documents/teachers/unit3/EinsteinsTrainGedanken.pdf

Note the authors' comment that there are a lot of versions about, some quite misinformed.

No there is no third, fourth or what ever observer involved and there are only two frames, the frame of the train and the frame of the platform.

The referenced article explains quite well what you may be thinking of as a third observer as the point of view that the train is standing still and the platform is moving past it.

However, as far as I can see all this is entirely off topic and you have made no response at all to my comments on the actual topic of this thread viz spooky action at a distance.

I suggest the relativity issue be further discussed in its own thread as it is entirely off topic to action-at-a-distance, spooky or otherwise.

16 hours ago, studiot said:

I must admit that it is a long time since I last looked at Einstein's train and lightning though experiments and I was thinking about the length contraction one.

I no longer have the original text of these experiments, but I have found a reliable explanation online here.

https://www.vicphysics.org/documents/teachers/unit3/EinsteinsTrainGedanken.pdf

Note the authors' comment that there are a lot of versions about, some quite misinformed.

No there is no third, fourth or what ever observer involved and there are only two frames, the frame of the train and the frame of the platform.

The referenced article explains quite well what you may be thinking of as a third observer as the point of view that the train is standing still and the platform is moving past it.

However, as far as I can see all this is entirely off topic and you have made no response at all to my comments on the actual topic of this thread viz spooky action at a distance.

I suggest the relativity issue be further discussed in its own thread as it is entirely off topic to action-at-a-distance, spooky or otherwise.

You are right. Relativity has nothing to do with it, outside the light speed limit part....but wait. I am still thinking the observer part is crucial. For this reason. Action at a distance needs a here and a there in order to even be a question. So the observer's frame of reference that is "here" is important. And the "paths" available to "there" are important as well. If information can get from here to there FTL then "something" can make the trip, that is not a particle or electromagnetic or gravity wave. My "guess" is that somehow the two locations are connected and the thing connecting them is analogous to a shaft or a wheel, when you move the one end the other end moves at the same time,

Regards, TAR

16 minutes ago, tar said:

You can't prove a negative. You say there is no absolute frame of reference, but you could only say that if you were assuming one cannot have a point of reference. Human existence proves the opposite, there IS a point of reference available, that is an observer, a human observer on Earth. So you say there is NO absolute frame of reference which now becomes an argument against God. And you take on the perspective of God and replace him with the lightcone and E=mc squared and curved space and dark energy and dark matter, anti particles, and nuetrinos and predictions that the universe will end in 300B years, as if you can contain the Universe, all of space and time in your mind, in an equation.

Well I have been around for 71 years. I have taken math and physics courses, I have read books on QED and relativity. I could not find my book where Einstein explained the train and lightning relativity thing, so I don't have his words to use in this discussion at the moment but I did fine Hermann Bond's Relativity and Common Sense, A New Approach to Einstein, Copyrighted in 1962 and 1964. I read it then and am looking through it now. Reading on the internet, various articles about relativity, I see a lot of misinterpretations and conclusions being drawn about what Relativity is, what it shows and what it might "predict". I will have to reread the book, but a general idea I get, related to this thread is it is important to apply common sense to the equations and not let the equations take you into dreamland where science is not applicable, and hypothesis can not be tested.

My proposal is you accept the fact that the universe is immense and long lived and complicated yet intertwined in a manner that is WAY beyond our comprehension and that you and I are in and of this thing.

What you and I then worship of it is a personal choice. Whether you disbelieve in a creator or are agnostic about it, or believe there is a creator is really immaterial,. The reality is, there is a Universe, and it is too immense and long lived and intertwined to hold within our tiny collection of nerves and synapses and folds and cortexes. We can contain a model of the thing, but we cannot contain the thing. When we perform a calculation, we are performing a manipulation of model. Applying transforms to bring one analogy into another context. In essence we are taking a god like perspective and manipulating the universe or our analog model of it, within our brains.

I say this gives us the ability to take a god like perspective. You don't have to posit God to take this perspective. You just have to take it. We do it all the time when we put hypothetical observers on planets lys away and move them around at "relativistic" speeds. But here is where common sense comes in. What you can do with your transform is limited. You had to simplify the problem in order to get an equation you could integrate or find the derivative or add together or square or cube or apply your transforming equation to. My common sense approach says that when you simplify in this manner, you are absolutely going to be dropping out elements of reality that MAY be crucial to describing reality correctly. And just because the equation works in your head, doe not mean reality will follow the equation. Might in a general sense. But if you are calculating how much milk you are going to get, you cannot have any 1/2 cows in the equation.

What this thread is about is Spooky Action at a distance. Something Einstein came up with i believe when thinking about entangled particles. This action at a distance breaks causality and breaks the light speed limit. So I started the thread to speculate on what mechanism might be present to allow for spooky action at a distance, that would NOT break causality or the speed limit. Such as the domino thing where the same cause can spread out and create effects in an ever increasing spherical shell. To envision this shell you have to take on a godlike perspective and "see" the shell expanding.

Regards, TAR

Exchemist,

I apologize. I pulled it in out of the blue. It was from a book I read where Einstein is describing the train and lightning strikes observed from the moving train and from a stationary observer on the side of the tracks.

I can't find the book. So I really can't refer to it properly. I am 71 and my memory is somewhat challenged. So although it is central to the discussion of the theory of relativity because the assumptions made during that explanation ARE the assumptions of the theory, I will have to drop the line of questioning because I can't locate the witness.

Regards, TAR

I'm the same age as you, then.😊

I think you are rather overdoing things if you think the absence of a preferred frame of reference is somehow an argument against God. Don't forget the Big Bang theory, which depends on general relativity, was originally proposed by a Catholic priest, Mgr. Lemaître: https://en.wikipedia.org/wiki/Georges_Lemaître

As for predictions that cannot be tested, the point surely is that for a theory to be scientific it must make testable predictions. General Relativity obviously does this. Even our GPS systems wouldn't work without GR. However, I don't think that means that every prediction or speculative extrapolation that one can make from it necessary has to be testable.

As for Einstein's "spooky action at a distance", my understanding is this was one of Einstein's rare errors in that in modern physics there is no such thing. Quantum entanglement does not imply any instantaneous communication between the correlated entities.