On the idea of time in physics-relativity

Very well said. In math terms:

$$dt'=\gamma(dt-\frac{vdx}{c^2})$$

Since $$dt=0$$ (simultaneous in frame F)
and
$$dx=0$$ (co-located events)

it follows that:

$$dt'=0$$ (i.e , simultaneous in any other frame F')

i.e. what you call "universal simultaneity".

Not that it will help convince the crackpot "professor".

"Universal simultaneity" is a bit of a misnomer on my part. It is very difficult to explain simultaneity to someone who has no clue.

So, "universal simultaneity" exists. That means there is also "universal time".

No, just because some events (which happen at the same time and place) will be observed to be simultaneous by all observers does not mean that all events are.
 
"Universal simultaneity" is a bit of a misnomer on my part. It is very difficult to explain simultaneity to someone who has no clue.

This is precisely why I used math, it shows a type of simultaneity agreed upon by ALL observers.
 
In the MME, and like many other experiments done on light since Einstein brought up this problem, shows that an object in motion will recieve two light beams at a location that is the same distance away from each other at the same time. Einsteins thought experiment did not make this prediction. It predicted that the beams of light would arrive at different times.

If, and only if, the two light beams were emitted simultaneously in the train frame would they reach the train observer simultaneously. The train observer does not see the light to travel at any speed other than c, but observes a difference in time between the two spatially separated events.

This is the simplest of SR, and all of your ignoring posts which explain this, flailing about non sequitur QM, arm waving, dodging, and generally being trollish about it does nothing to obscure your appallingly stubborn lack of understanding from anyone here.
 
Maybe you should try reading it more slowly. All it means is that when an object is in motion and two light beams are sent to the same location, then they will arrive at the same time. That was the discovery that was made in the MME.
You still aren't setting this up correctly. You continue to ignore that the light flashes are simultaneous on the platform, but the train's motion excludes it from that frame.

Did you miss the whole point of the thought experiment?
The point was that simultaneity is relative. That's your stumbling block, not mine.

The thought experiment shows that two beams of light do not arrive at the same time to the observer on the train.
Because the train is in motion relative to the inertial reference frame centered at the platform observation point. You keep ignoring this crucial fact.

In the MME is considered to be in motion, the beams of light reach the detector at the same time.
There is no "considered to be in motion". You need to shake yourself of that nasty habit. There is only relative motion. And it has nothing to do with MME.

Einstein like many other scientist, didn't know what the results of the MME would be.
As I said before, he was a child when MME took place. But it's all moot, since MME has nothing to do with relativity.

Everyone was surprised that they arrived at the same time.
Because they expected to detect the ether wind. (Also irrelevant.)

When confronted about this issue, he claimed that he wasn't aware of the results of the experiment
Moot, irrelevant and at least partly false. Give it up.

and published theories in contrary to what the experiment said.
Hah! I gave you the link to the paper where he denounces ether. More BS.

It doesn't mean relativity is false, I didn't say that it was false.
As soon as you deny the relativity of simultaneity you are denying SR. You can't have one without the other.

Relativity isn't ever explained in any books as being caused by simultaneity,
More absurd pontificating. No one ever said simultaneity "causes" relativity. You continue to ignore what Einstein actually said.

except in Einsteins own publishings.
More BS. Contrast your bombastic opinions of what Einstein published vs the Einstein's own introductory definition of the term. One thing you can learn from him is the importance of defining terms before you start piling on the assumptions, convolutions and manglings.

If we wish to describe the motion of a material point, we give the values of its co-ordinates as functions of the time. Now we must bear carefully in mind that a mathematical description of this kind has no physical meaning unless we are quite clear as to what we understand by “time.” We have to take into account that all our judgments in which time plays a part are always judgments of simultaneous events. If, for instance, I say, “That train arrives here at 7 o'clock,” I mean something like this: “The pointing of the small hand of my watch to 7 and the arrival of the train are simultaneous events.”

It is explained as the light clock example, that isn't entirely correct either.
Right. After the massacre of the principle of relativity of simultaneity, let's attack another basic concept. All while claiming you're neither anti-science nor anti-SR. That pretty well clinches it.

This is because the light clock example doesn't produce the correct equation.
That's to Einstein’s credit, since all of your reasoning is at best pseudoscience.

This is why I have shown how an example close to the light clock can produce the same equation for the proper time.
You don't do math. You don't comprehend relativity. You haven't shown anything except your laundry list of defective reasoning. That really doesn't leave you any chops, does it?

It is only a simple shortcut that doesn't use a lot of the more complex mathmatics that Einstein used.
That sounds like an admission of guilt.

So then I agree, that the equation for the proper time is correct, but it doesn't say anything about when beams of light arrive at locations. The correct interpretation of that is always described as the MME experiment.
MME doesn't involve two reference frames. You're losing miserably. Give it up.

The reason why they did away with classical mechanics is because no description of classical mechanics produce the results found in experiments on particles.
No one did away with anything. You just don't get it, do you? The Maxwell-Einstein era was a transitional period that ushered in new discoveries. Science is a living document, a work in progress. Relativity is an update, a refinement, to Newtonian kinematics. Quantum physics was emerging in parallel and brings further refinements (and opens new doors). But they all complement each other; the story could never have unfolded without the successive acts of nailing stakes in the ground and moving forward. You've completely twisted the synergy of human technological history into some insane personal vendetta against icons like Einstein.

It isn't because they could not figure out what classical mechanics describes particles, it is because classical mechanics actually does not and can not accuratly describe them.
That sounds like someone trying to explain what I just said to a 3rd-grader. You still seem to have no clue what science is and what drives discovery.

It means that when they discovered quantum mechanics that the behaivor of particles was so different that normal everyday physics,
Suffice it to say that particles were discovered to have certain quantum states.

that they had to invent new mathmatics and physics in order to be able to describe the results that they got from experiments.
Your oversimplifications are really tiring.

The physics of the time of Newton just wasn't good enough in order to descibe particle nature.
Which is why quantum physics didn't exist in Newton's era.

The final conclusion of the thought experiment is that the beams do not arrive at the same time.
In the reference frame of the moving train. You keep ignoring that.

This is not the result found by experiment.
Presumably you mean MME, which has been shown to be nonsense. So when are you going to update yourself with the new information?

I was talking about the flashes of light being particles, that scientist call photons.
Photons are understood to propagate as waves, not particles, so be careful. You're about to step in another cartload of your own BS.

I was saying that the arrival time of the photons inside of the train would have to be descibed by quantum mechanics, not that the train itself would have to be described by quantum mechanics.
They don't arrive as particles, but as waves.

Quantum Mechanics would tell you when those particles arrive at the same location, and then since it is based on the MME, then they would arrive at the same time.
According to your diatribe to this point, that's nothing more than classical kinematics. It was superseded by the discovery of relativity. When are you going to update yourself?

Basically that the observer on the station, and the observer on the train would measure the beam in front of the train and the beam behind the train to travel at the same speed.
Since c is constant in all frames, that's moot.

So take a look at the diagrams in the thought experiment, their is a difference in how much the beam approuches the train from the front and the back relative to the observer on the train. There cannot be this difference in motion, since the observer on the train will measure both beams to travel the same speed at the same time.
How many times are you going to rehash this? Once again you are ignoring the basic principles of relativity. The only diagram you need to understand is the spacetime diagram for what happened on the train as seen from the platform point of view:
250px-TrainAndPlatformDiagram2.svg.png

If the observer on the train could measure a difference in how much closer or further away it got from each beam, then the observer on the train wouldn't acctually measure both beams to be the same speed at the same time.
Translation: you haven't understood one iota of relativity.

The theory doesn't actually describe particles themselves, it is more like a description of how the speed of light plays a role in other objects that are not particles.
Actually, the in 1905 ED paper AE does devote some explanation to the consequences of relativity for particles. But since this is about waves, not particles, you need to shift your focus away from the nutty idea that QM refutes the train example. Again, you still are in denial -- and/or refuse to and/or are incapable of -- learning the basics of SR starting with the diagram immediately above.

The actual theories that describe the actual particles are not exactly what is in his 1905 paper.
Yes he does treat particles to the extent it's pertinent to his thesis. Of course this is more BS.

You wouldn't check his paper in order to figure out how particles behave for instance.
Except in matters of propagation, which he explores meticulously by associating Lorentz with Maxwell.

In a lot of books it says that Einsteins theories are not used in quantum mechanics.
A lot of books are written by people like you.

Einsteins theories describe the macroscale, like normal everyday sizes, and quantum theory is used to describe the microscopic scale.
More BS. Einstein specifically addressed particle and wave phenomena under application of Lorentz's updates to electromagnetics. You need to analyze relativity under the lens of the laws that describe relativity, not some imaginary system you've invented in your mind which purports to be QM but is nothing more than an oversimplification of classical kinematics.

His theories and quantum theory apply to different things, and these two theories have not been combined into one theory that can describe both. They are not compatable.
In your mind, which is not compatible with reality.

I didn't develop these opinions on my own,
No doubt you lifted them from some pseudoscience sites.

most of the time Einsteins 1905 paper is ever mentioned is when someone is writing about SR, they just don't ever refer to it in quantum atheory.
That's worth several cartloads of BS. Rather than worrying about how you think other people treat Einstein's paper, you need to be able to digest it yourself. You're deliberately ignoring the content of what he said and talking about what some imaginary group of people are saying -- apparently pseudoscience crackpots.

Quantum theory that scientist use was developed by different people. No scientist uses his work in quantum theory.
As long as you continue to pontificate and refuse to investigate, analyze and rebut the issues, this is just pile after pile of BS.

If you wanted to describe the actual photons on the train that would be a better choice.
Except they don't exist as material particles but as waves. Another act of pontification crashes and burns.

If you wanted to describe the time dilation of the train itself, then Einsteins theory would be the better choice.
Since the whole subject is relativity, and since you alone seem to be opposing Einstein, that leaves us inside the actual language and the actual principles of relativity, which, to date, you refuse to address. The crux of your error is that you don't understand the diagram above. The rest is Styrofoam/BS/bluster.

all I am saying is that in Einsteins thought experiment, the conclusion is wrong about the arrival time of the photons, and his theories are not descriptions of photons themselves.
Still wrong. Arrival of waves, not photons. In any case, apply the diagram.

They already have proved over and over with experiments that an object in motion will have two beams traveling the same distance reach the same point at the same time.
Who's this "they"? That's absurd. We're talking about relativity, in which case the paths are not equal from the platform point of view. Among other things.

I am just repeating the words of science writters.
Well that's a relief. At least they weren't writers. Einstein was a prolific writer, and right now he's the one on the carpet. You've proven that you cannot even parrot what he said. So your point is . . . ?

Really, you can't spell at the elementary school level? Look, dude, this is really like trolling. You seem determined to pretend you've got the IQ of an ant while pretending to know advanced physics. Regardless, it's evident that you can't understand what you're reading, so what diff does it make if you ever read a science article or not?

They all cannot be wrong, but I think you can.
Considering you process information like a paper shredder, I take that as a compliment.

You will never convince me otherwise because I have already read the same thing being put out as scientific fact from dozens of different science writters.
No, you will never be able to convince yourself of what people are actually writing (here or elsewhere) because of your learning issues. You simply can't repeat back fundamental ideas. Worse, you fill in the deficit with pontification.

So either they are all wrong, or you are wrong,
Or you are wrong. Which wins by a landslide.

I will always pick you are wrong.
Which evidences pseudoscience and denial, your two greatest stumbling blocks.
 
The only source I know of that explains relativity of simultaneity is Einstiens book. In every other singal book that I know of, it explains SR with the MME not with relativity of simultaneity. (this would be why no one ever knows about it when they first start talking about relativity in science forums) The only place I know of where relativity is described in such a way is Einstiens own book. I don't know of any other description of relativity of simultaneity, because frankly it is a giant load of bull and no real scientist in his right mind would care to repeat it. This is why when theoretical physicist write about SR, they don't ever mention it. It is physics deep dark secret that they are trying to keep quite.

Here's a section from a standard undergrad physics text (Halliday & Resnick's Fundamentals of Physics. Don't know what edition, it's from a pirated pdf).
Simultaneity.png
 
I understand that in illustration (b), observer O' receives the light at the same time. My question is if the motion of the train independently causes a red or blue shift in the light even though the observer O' receives them at the same time.

My reasoning is that one beam travels @ c + train speed, while the other travels @ c - train speed. While this does not affect the speed of the light, could it cause a red/blue shift of the light itself to one or the other observer?

What would happen (if anything different) if the train was moving at near SOL ?
 
I understand that in illustration (b), observer O' receives the light at the same time. My question is if the motion of the train independently causes a red or blue shift in the light even though the observer O' receives them at the same time.
Illustration (b) shows the flashes reaching observer O at the same time. The flash from A and A' has not yet reached O', the flash from B and B' has already passed O'.

Yes, the relative motion means that O' will measure the flash from A and A' to be redder than O measures it, and vice versa for the flash from B and B'.

My reasoning is that one beam travels @ c + train speed, while the other travels @ c - train speed.
Well, both beams are traveling at c, but perhaps you mean that the distance between O' and the flashes changes by (c+v) and (c-v), because the flashes move at c and -c, and O' moves at v?

What would happen (if anything different) if the train was moving at near SOL ?
The illustrations are drawn in the reference frame of O, (they show O to be stationary and O' to be moving to the right).

If the illustration was drawn in the reference frame of O' (with O' stationary and O moving to the left), you would see some differences:
  • The distance from A' to B' would be longer
  • The distance from A to B would be shorter
  • Three things that happen at the same time in illustration (a) would happen at different times:
    • The right-hand lightning bolt would strike first (when B passes B')
    • Then O would pass O'
    • Then the left hand lightning bolt would strike (when A passes A')
But the speed of the light flashes would not change (they would both move at c), and they would both reach O at the same time.
 
Not true, Layman, and not logically possible.
Look:
eintrain.gif


The two observers are not in the same place when the flashes arrive, so it's impossible for the flashes to reach both of the at the same time.

This is not the same as the MMX, which has only one observer, comparable to the platform observer.
Your finally starting to get it. It is not logically possible for the beams to reach the middle of the train at the same time. But, this is what happens in the MMX, the logically impossible, the beams arriving at the middle of the train at the same time. Since the behavior of light is determined by actual experiment, and not logic, then you would be wrong thinking that you could logicallly think about quantum states and then be correct about them.

You people don't realize this because you don't know what the results should even be in experiments where light is sent to the same location on a moving body at the same time. If you knew about these experiments, then you wouldn't have this problem.
 
If, and only if, the two light beams were emitted simultaneously in the train frame would they reach the train observer simultaneously. The train observer does not see the light to travel at any speed other than c, but observes a difference in time between the two spatially separated events.

This is the simplest of SR, and all of your ignoring posts which explain this, flailing about non sequitur QM, arm waving, dodging, and generally being trollish about it does nothing to obscure your appallingly stubborn lack of understanding from anyone here.
This is intellectual dishonesty, your just making this stuff up. Nowhere does it say that the arrival time would be different only because they are sent from the same location or not. I am calling your bluff on this one, buddy.

The light beams would still travel against the direction of motion even when they are sent from the same location. So then the reason why there is not simultaneity, would still be present even if they are sent from the same location at the same time. I showed this in figure 4. on the wiki page of the MMX.
 
There is no "considered to be in motion". You need to shake yourself of that nasty habit. There is only relative motion. And it has nothing to do with MME.
I picked it from Ph.D's that write books on the subject. An object can be considered to be in motion. To say otherwise makes you a crank. The MME has been tested for objects that are in relative motion, and has produced the same results.


As I said before, he was a child when MME took place. But it's all moot, since MME has nothing to do with relativity.
That is because you have never read a book from your local library. There would be a 90% chance that it mentions the MME with relativity, and not mention anything about relativity of simultaneity!

As soon as you deny the relativity of simultaneity you are denying SR. You can't have one without the other.
I just don't think the assumption that the light beams will reach the observer on the train at different times because this is not what has been shown to happen in experiments..

MME doesn't involve two reference frames. You're losing miserably. Give it up.
It is actually used in a lot of books to explain properties of light, and it is said in all of them that a MME that is considered to be in motion will give the same results as it did at rest on Earth.

In the reference frame of the moving train. You keep ignoring that.
You keep ignoring the fact that almost every book that explains the MME while considered in motion, that the beams of light arrive at the same time.

Presumably you mean MME, which has been shown to be nonsense. So when are you going to update yourself with the new information?
And you say I am posting anti-science? You just said the defining experiment of modern physics of the 20th century was nonsense. No wonder why you insist on trolling me by taking everything I say apart and twisting it around to make it sound like BS.

Photons are understood to propagate as waves, not particles, so be careful. You're about to step in another cartload of your own BS.
I think you just stepped into a cartload of it. They are both a particle and a wave. The particle itself is called the photon. I could no longer trust anything you say now that you have said that, it would be impossible for me to assume that you know something about particle physics because of this statement.

They don't arrive as particles, but as waves.
Again they are both particles and waves.

Translation: you haven't understood one iota of relativity.
Translation : you haven't understood one iota of particle physics and the interpretations of the experiments in it. They don't call it wave physics for a reason.

Actually, the in 1905 ED paper AE does devote some explanation to the consequences of relativity for particles. But since this is about waves, not particles, you need to shift your focus away from the nutty idea that QM refutes the train example. Again, you still are in denial -- and/or refuse to and/or are incapable of -- learning the basics of SR starting with the diagram immediately above.
This would be the same exact thing you accuse me of doing, you seem to think that there is some significant difference in photons being waves and not particles. You would be incapable of learning the basics of particle physics.

A lot of books are written by people like you.
Then I would really like to know who their publisher is, the last time I checked most books written about physics was written by physics professors. You might be able to find some of these on the internet, if so, hook me up.

No doubt you lifted them from some pseudoscience sites.
No doubt you have no idea. I actually despise a lot of people in the pseodoscience section, because they are so far off and out there it has made it impossible to make a valid point. People like you that are totally ignorant of a subject, will then assume incorrectly about the knowledge people have of theoretical physics, mainly because legit theoretical physics can be kind of out there. Since you have no real knowledge of it, then you can't distinguish between the two. So then you end up trolling people that state facts about theoretical physics because you believe that they are making it up under these false pretenses, when it is really because you don't know anything about it. So then what people view as scientifically accurate is determined by someone that really has no idea about the subject. Then they will accuse people that do know about it that they are wrong about things and they are correct. This effect has been fully explained earlier in this thread...


Except they don't exist as material particles but as waves. Another act of pontification crashes and burns.
Just like your credibility.


Still wrong. Arrival of waves, not photons. In any case, apply the diagram.
You really dabble in complete ignorant nonsense don't you?


Who's this "they"? That's absurd. We're talking about relativity, in which case the paths are not equal from the platform point of view. Among other things.
Scientist that determine properties of light being emitted from objects in motion. That is why they still claim that the MME is equally valid if considered to be in motion.

No, you will never be able to convince yourself of what people are actually writing (here or elsewhere) because of your learning issues. You simply can't repeat back fundamental ideas. Worse, you fill in the deficit with pontification.
Do you hear this a lot and have sudden urges to then repeat this to other people?
 
Your finally starting to get it. It is not logically possible for the beams to reach the middle of the train at the same time. But, this is what happens in the MMX, the logically impossible, the beams arriving at the middle of the train at the same time.
Please, Layman - take your own advice and open a textbook.

There is nothing illogical in the MMX.
In the MMX, there is only one detector (observer).

In the train thought experiment, there are two observers, who are in different locations when the flashes arrive. The light flashes only meet once. This meeting can only be at one observer's location.

The MMX detector is not like the train observer. The MMX detector is a little bit like the platform observer, because the light flashes hit the mirrors simultaneously in the detector rest frame.
 
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Prof. Layman to better understand your position I have supplied a simple picture that shows a moving source (the dot, which is moving at a significant fraction of c) and an expanding light sphere (the circle). This is event is being viewed from an inertial reference frame that is stationary relative to the moving source. There are 2 cases shown. I have a very simple question - which one represent what would actually happen? If you have an questions about the set up feel free to ask.

View attachment 6166
 
There is some irony in that, almost by definition, one is not able to "turn a crank".

Your "turn" of phrase gave me pause, followed by comic surprise and a somewhat awesome sense of the profound. Good timing too. ;)
 
Please, Layman - take your own advice and open a textbook.

There is nothing illogical in the MMX.
In the MMX, there is only one detector (observer).

In the train thought experiment, there are two observers, who are in different locations when the flashes arrive. The light flashes only meet once. This meeting can only be at one observer's location.

The MMX detector is not like the train observer. The MMX detector is a little bit like the platform observer, because the light flashes hit the mirrors simultaneously in the detector rest frame.

Thank you.

But will he ever get it? It seems to be beyond his capacity to comprehend.
 
I picked it from Ph.D's that write books on the subject.
Name one.

An object can be considered to be in motion. To say otherwise makes you a crank.
All motion is relative to an inertial reference frame. Find one book that says otherwise.

The MME has been tested for objects that are in relative motion, and has produced the same results.
Prove this.

That is because you have never read a book from your local library. There would be a 90% chance that it mentions the MME with relativity, and not mention anything about relativity of simultaneity!
Prove that MME has anything to do with this thread topic.

I just don't think the assumption that the light beams will reach the observer on the train at different times because this is not what has been shown to happen in experiments..
Name one experiment that proves it wrong.

It is actually used in a lot of books to explain properties of light, and it is said in all of them that a MME that is considered to be in motion will give the same results as it did at rest on Earth.
Name one book that says so.

You keep ignoring the fact that almost every book that explains the MME while considered in motion, that the beams of light arrive at the same time.
Name one book that uses MME to disprove Einstein's train scenario.

And you say I am posting anti-science?
Anti-science nonsense. Yes, the record speaks for itself.

You just said the defining experiment of modern physics of the 20th century was nonsense.
Typical misquote. I said your posts are nonsense. I said your rationale for invoking MME is nonsense. Bring on the evidence, or let it go. Otherwise you're trolling.

No wonder why you insist on trolling me by taking everything I say apart and twisting it around to make it sound like BS.
Typical blame-shifting of the anti-science crank.

I think you just stepped into a cartload of it. They are both a particle and a wave. The particle itself is called the photon. I could no longer trust anything you say now that you have said that, it would be impossible for me to assume that you know something about particle physics because of this statement.
Photons propagate as waves. Refer to your "books".

Again they are both particles and waves.
They propagate as waves.

Translation : you haven't understood one iota of particle physics and the interpretations of the experiments in it. They don't call it wave physics for a reason.
They propagate as waves.

This would be the same exact thing you accuse me of doing, you seem to think that there is some significant difference in photons being waves and not particles. You would be incapable of learning the basics of particle physics.
They propagate as waves.

Then I would really like to know who their publisher is, the last time I checked most books written about physics was written by physics professors. You might be able to find some of these on the internet, if so, hook me up.
I was referring to crank publications. And I did already hook you up to an authority on this subject, AE's 1905 electrodynamics paper. You said nothing that indicated you had digested one iota of what AE said.

People like you that are totally ignorant of a subject, will then assume incorrectly about the knowledge people have of theoretical physics, mainly because legit theoretical physics can be kind of out there.
There's nothing in controversy about your ignorance of physics. You've admitted it, and demonstrated it, yet at the same time you are pretending to be someone else, someone who is knowledgeable in the subject. Your posts are strewn with nonsense, fallacies, errors and absurdities, yet you persist with the pretense of knowledge. Yet you can prove nothing, you are unable to apply the rules of logic toward the development of even a simple postulate, you can't so the simplest of math, and you are unfamiliar with the physical interpretation of the laws and principles encoded in the math. Yet you sit in judgment of Einstein.

Since you have no real knowledge of it, then you can't distinguish between the two. So then you end up trolling people that state facts about theoretical physics
You mean I correct you when you dump absurdity, nonsense and BS into the thread.

because you believe that they are making it up under these false pretenses,
Q.E.D.

when it is really because you don't know anything about it. So then what people view as scientifically accurate is determined by someone that really has no idea about the subject. Then they will accuse people that do know about it that they are wrong about things and they are correct. This effect has been fully explained earlier in this thread...
So far the people you pretend to be worried about are waiting to see you put up or shut up. Put your money where your mouth is. Be a man, belly up to the bar. Simply prove that MME has any relevance to this thread or yield.

Scientist that determine properties of light being emitted from objects in motion. That is why they still claim that the MME is equally valid if considered to be in motion.
Prove that MME has any relevance to the train-lightning scenario, and move on.
 
No, just because some events (which happen at the same time and place) will be observed to be simultaneous by all observers does not mean that all events are.

Why two events happening anywhere in the universe can not be simultaneous?

May be there is no such "universal clock" to measure this "universal simultaneity", but that's a different issue.
 
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