Simultaneity - Albert Einstein and the Theory of Relativity

The second postulate says that the SPEED of light is constant. Not DISTANCE: it's different for the man and the woman! That's exactly why there CANNOT be simutaneity! Do you actually think that Einstein didn't understand his own theory?

Where's the flaw in my posts? Instead of repeating the same gibberish over and over again, answer my questions: what does the man see when he looks at the woman? What does the boy see? Answer my questions and stop escaping!

Pulsar98, I'm waiting for you to acknowledge clearly that there's no relativity of simultaneity exactly because of the second postulate and because of Einstein's insistence that simultaneity must be studied judging by the arrival of light rays with observers. The man in his system sees the beams simultaneously. The woman in her system sees the beams simultaneously as well exactly because of the second postulate. You have no other choice but to agree with this and not continue to post gibberish.

Pulsar98, I will try it again. What you're saying about the man in your five postings follows entirely from classical physics (physics without the "theory" of relativity). Therefore, don't try to foist it on us as if it is a discovery of the bogus "theory" of relativity. Because it's classical physics and, despite your impression, because it obviously doesn't prove relativity of simultaneity this should not be discussed further in this context.

part 5
so the boy will see the beams simultanously. But when that happens, he will have run a certain distance inside the train: he's BEHIND the woman. If the boy sees the beams simultanously, the woman CANNOT, because there's a distance between the woman and the boy, and the speed of light is finite. The front beam passes the woman first before it hits the boy. The back beam passes the boy first before it hits the woman.

part 4
I'll give you yet another argument: suppose there's a third person, a boy, running inside the train. If the train has velocity v, he runs in opposite direction at velocity -v compared to the train. In other words, he remains stationary with respect to the man on the ground. Suppose that when the beams hit the train, the three persons are in the middle, so the boy just passes the woman. What happens for the boy? He's in the same frame of reference as the man on the ground,

part 3
In other words: the order of two events (lightning) happening at SEPARATE places (the front and back of the train) depends on the point of view. But the order of two events happening at the SAME place (the woman's head) is the SAME, regardless of the point of view. Otherwise, you get logical contradictions with causality.

part 2
Why not? Let's suppose she does. Then both beams hit her head, and both beams reflect from her head at the same time. So both beams then travel side by side from the woman to the man. Therefore, the man would also see the beams hitting the woman simultanously. But that's a logical contradiction, because of what I said above.

part 1
Gosh, you guys are impossible. I'll try once again. The man sees the beams hitting the TRAIN simultaneously. But when he looks at the WOMAN, he sees the first beam hitting her face BEFORE the second beam hits her back, simply because she has a velocity. While the beams travel to her, she moves, so she no longer sits in the middle of them, from the man's point of view. This is VERY basic physics, no need for relativity. And because of this, the woman CANNOT see the beams simultanously.

I was struggling to understand this concept in class due to substandard teaching, so thankyou for posting this

omnibus101, you realy are correct, since if you were travelling towards or away from light at any speed, light will still pass you at the speed value of c, in other words when light is concerned your velocity does not matter, thus the motion of the train also does not matter. as far as light is concerned the woman is stationary just like the man. i am sure if the woman had eyes at the back of her head she would agree with omnibus101..( she sees the beams sim ultaneously)..

I concur.

Pulsar89, I know you want to sidetrack and discuss other issues but I won't let you off the hook. The man in his system sees the beams simultaneously. The woman in her system sees the beams simultaneously as well exactly because of the second postulate. No relativity of simultaneity. You have no other choice but to agree with this.

Why this people didnt understund That simple Universè? why they believe some magic dimension? There is only three dimension. Space dont expanding or bend simsalabim.

Check out, Idea from Kuopio, video, and you know lot of more that Universe what this men's ever know.

Real model of an atom

The atomcores expand three-dimentionally, opening up energywaves that have
the nature of electron and photon.

Lets make a Re:Idea from Kuopio

I'm off now, I'll read your reply later.

And what would happen if the train traveled at the speed of light? The woman would see the first beam immediately, but the second beam would travel at the same speed as the train, side by side, so it could never reach her. So for her, the second lightning would happen an infinite amount of time after the first, i.e. never.

sigh. Look at the man. From his point of view, the woman travels towards the light, right? From his point of view, he sees the first beam hit the woman's face before the second beam hits her back. Do you agree with this?

Pulsar89, don't finagle. The man in his system will see the beams arrive simultaneously with him. The woman in her system will also see the beams arrive simultaneously with her because of the second postulate and the equidistant from start of the beams in her system. Simultaneity isn't relative exactly because of the second postulate.

Let's do this in classical mechanics. The woman travels at speed v, so the first beam would hit her first. From her point of view, both beams are equidistant. But in classical mechanics, she would measure a higher speed c+v for the first beam, and a lower c-v for the other. So from that, she would conclude that she's not in rest.
The difference with relativity is, that she won't measure a difference between the beams, so she can only conclude that the events are not simultaneous.

Pulsar89, on the other hand, what you describe is from man's PoV and comes about purely classically (without relativity). No one in his right mind will start insisting that such trivial observation in classical physics proves relativity of simultaneity

Pulsar89, you say you've read what I've written but you obviously haven't. The points in woman's frame where the lightning bolts fall and the light rays start towards her are equidistant from her. The velocity of light is c = const in her system as well, according to the second postulate. Therefore, contrary to Einstein's conclusion the light rays will reach her simultaneously as they'll do with respect to the man. No relativity of simultaneity.

Let's think of a machine in the middle of the train that would set off a alarm if both beams would hit it at the same time. Now, how could the alarm go off for the woman, but not for the man? A contradiction, no?

The video seems correct to me. I've just read your previous posts. You seem to think that the woman sees the beams at the same time. That's not true, because she's traveling towards one of the beams. The first beam has to travel less far and hits her face before the other hits the back of her head, just like the observer would see if he would look at her.

Pulsar89, you want to take your word for it that you're finding more and more confirmations but you can't do a simpler thing. You can't explain away the crucial mistake made in this video, invalidating that "theory" in its entirety. If relativity were true you could've defended it right here and not pull the wool over our eyes by listing completely irrelevant information. Is avoiding the problem by substituting it by gibberish what professional astronomers do?

Ah, the motion of the spaceship itself? As long as its speed is smaller than c relative to the observer, he can see it, but he would see the pilot inside the ship in slow motion.

But if the ship has velocity c compared to the observer, then the ship would become invisible for him: it would have an infinite doppler shift.

1 sorry pulsar89, what you are saying does not make sense, it will take a second of our time for the observer to observe that light has travelled 300000km, but it would take infinite amount of time for the oserver to observe any motion of the spaceship. since we depend on light to observe motion, and light must be constant in all frame of ref, things becomes harder to observe when moving close to the speed of light. example would be electrons.. do you magree?