On the idea of time in physics-relativity

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

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.

 

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This is precisely why I used math, it shows a type of simultaneity agreed upon by ALL observers.

 

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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.

 

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I appreciate it, though as you say, I am sure it is completely lost on PL.

 

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.

The point was that simultaneity is relative. That's your stumbling block, not mine.

Because the train is in motion relative to the inertial reference frame centered at the platform observation point. You keep ignoring this crucial fact.

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.

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.

Because they expected to detect the ether wind. (Also irrelevant.)

Moot, irrelevant and at least partly false. Give it up.

Hah! I gave you the link to the paper where he denounces ether. More BS.

As soon as you deny the relativity of simultaneity you are denying SR. You can't have one without the other.

More absurd pontificating. No one ever said simultaneity "causes" relativity. You continue to ignore what Einstein actually said.

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.”​

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.

That's to Einstein’s credit, since all of your reasoning is at best pseudoscience.

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?

That sounds like an admission of guilt.

MME doesn't involve two reference frames. You're losing miserably. Give it up.

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.

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.

Suffice it to say that particles were discovered to have certain quantum states.

Your oversimplifications are really tiring.

Which is why quantum physics didn't exist in Newton's era.

In the reference frame of the moving train. You keep ignoring that.

Presumably you mean MME, which has been shown to be nonsense. So when are you going to update yourself with the new information?

Photons are understood to propagate as waves, not particles, so be careful. You're about to step in another cartload of your own BS.

They don't arrive as particles, but as waves.

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?

Since c is constant in all frames, that's moot.

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:

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Translation: you haven't understood one iota of relativity.

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.

Yes he does treat particles to the extent it's pertinent to his thesis. Of course this is more BS.

Except in matters of propagation, which he explores meticulously by associating Lorentz with Maxwell.

A lot of books are written by people like you.

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.

In your mind, which is not compatible with reality.

No doubt you lifted them from some pseudoscience sites.

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.

As long as you continue to pontificate and refuse to investigate, analyze and rebut the issues, this is just pile after pile of BS.

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

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.

Still wrong. Arrival of waves, not photons. In any case, apply the diagram.

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.

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?

Considering you process information like a paper shredder, I take that as a compliment.

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.

Or you are wrong. Which wins by a landslide.

Which evidences pseudoscience and denial, your two greatest stumbling blocks.

 

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).

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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 ?

 

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'.

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?

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.

 

Eureka, understand the illustration now.

 

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.

 

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.

 

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.

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!

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..

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.

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.

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.

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.

Again they are both particles and 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.

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.

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 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...

Just like your credibility.

You really dabble in complete ignorant nonsense don't you?

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.

Do you hear this a lot and have sudden urges to then repeat this to other people?

 

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

 

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.

 

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.

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Your "turn" of phrase gave me pause, followed by comic surprise and a somewhat awesome sense of the profound. Good timing too.

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Thank you.

But will he ever get it? It seems to be beyond his capacity to comprehend.

 

Name one.

All motion is relative to an inertial reference frame. Find one book that says otherwise.

Prove this.

Prove that MME has anything to do with this thread topic.

Name one experiment that proves it wrong.

Name one book that says so.

Name one book that uses MME to disprove Einstein's train scenario.

Anti-science nonsense. Yes, the record speaks for itself.

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.

Typical blame-shifting of the anti-science crank.

Photons propagate as waves. Refer to your "books".

They propagate as waves.

They propagate as waves.

They propagate as waves.

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.

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.

You mean I correct you when you dump absurdity, nonsense and BS into the thread.

Q.E.D.

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.

Prove that MME has any relevance to the train-lightning scenario, and move on.

 

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.

 

Yes, there is no such universal clock.