At 0:25 to 0:35, the video shows the train STOPPED but the light bubbles expanding toward the platform observer. This is NOT what really happens! In reality, the relative motion of the train past the man continues as the light bubbles expand toward the platform. The time he sees the strikes will therefore not be when they actually occurred.
It is quite possible for the 2 flashes of light to take place at different times (as determined by all observers) and still be observed simultaneously on the platform and non-simultaneously aboard the train. Since each flash requires a non-zero time interval to occur, the average distance from the front flash to the platform will exceed the average distance from the rear flash, as the car moves forward, and they will therefore reach the platform simultaneously.
@93HaD93 The case you are talking about is the classical case, where the velocity of light obeys the Galilean velocity-composition law and the speed (relative to the road) of the light flying towards the front is c + u and towards the rear is c - u (u is the car speed relative to the road, and c is the light speed relative to the car). Therefore the front and the rear are stroken at the same time, both in the car and on the road, and simultaneity is absolute.
@starnutente1 Thanks to you and to Leconsd so much. I am getting it.
Only another doubt. You say: "the speed (relative to the road) of the light flying towards the front is c + u and towards the rear is c - u (u is the car speed relative to the road, and c is the light speed relative to the car)".
Are they not u + c and u - c relative to the road?
This is part of the reason why the four gospel accounts are different aspects of the same events yet atheists claim contradiction......nope!!! If eyewitnesses say the exact same thing, verbatim, then they will be suspected of corroboration....they plotted their scheme...
You are probably (?) thinking about a MATERIAL object moving with constant acceleration (non-inertial reference frame). This is allowed in SR since the `equivalence principle` allows this situation to be viewed as the material object at rest (once again an inertial reference frame) subject to an external gravitational field.
if a light bulb at each end of a rapidly moving train were two turn on at exactly the same time, would the mid-point passenger see both at the same time? Would they be the same color?
the reason why I don't get it is that we are referring to two different frames, one for the train and one for the platform. so my question is: in which frame does the lightnings strike?
@Biarry sorry your answer don't help me much. I either have a problem with this concept or just its explanation.we explain doppler effect with that, we say that something that's in another frame and produces a sound does have doppler effect, but it just makes sense is the sound is in the frame away from me. if it belongs to both in the same way it does not make any sense (to me). the events HAVE to belong to some frame, if they don't, well frames does not make any sense to me.
no, einstein and the girl on the train are wrong! if the girl on the train looks to the back, she is actually looking into the past because all light coming from the back of the train has to travel a further distance than light coming from the front. just because we see something happen doesn't mean it's happening at that instant. when we look at the stars and the sun, do we see them as they are right now? no, we are looking into the past! same thing with the train.
@leviatam also, the train would have to be traveling at close to the speed of light, which would mean its relativistic mass would be enormous and time is slowed down inside the train, however this is irrelevant to the scenario.
Claiming that flashes of light from a moving source reach an observer at the same time (0:24) is equivalent to claiming that flashes of light from a stationary source reach a moving observer at the same time. The only way this can happen is if the flashes happen at different times.
Question for people who understand the physics of Relativity: would you please give constructive criticism on my video on whether Relativity is consistent with the Growing Block Universe Theory of Time? That would be awesome. Thanks.
@Laughingblades True, but the man stands on a planet. Planets definitely move so his frame of reference cannot possibly be "true".
One man realized a long time ago that - as long as it moves in a straight line at a constant speed - the movement of the planet (and the train) is irrelevant. There are no preferred ("false") frames of reference.
@Biarry Yes but on that planet, when two bolts of lightning strike at the same time that's no longer a mere point of reference, the simultaneity of impact doesn't change just because of a faulty frame of reference, and human lives could be put on the line in an experiment like this to make the point.
@Laughingblades Yes - for the people on that planet the strikes are simultaneous. For the people on board that train and any planet in the universe that (by pure chance) is standing still relative to the train the strikes are not simultaneous. We call this "special relativity".
And - since the special relativity is pretty much undisputed - I don't think we should put any human lives on the line here.
@Biarry Then by this definition of special relativity you're only referring to people's perspectives.
Because the simultaneity of the strikes is not contingent on your point of observation, it's contingent on whether the electricity hits the object at the same time, unless there's some time altering phenomena taking place you could put lives on the line with this. Suppose the train were rigged to derail if the strikes were not simultaneous, the point of view of the passenger would be irrelevant
@Laughingblades And what if there was no planet? No track, no station, no man?
The woman sits in the middle of her space train. She sees the front flash first, then the flash from the back. Are they still "objectively" simultaneous?
@Biarry Her perspective still doesn't effect the simultaneity of events, unless some special condition were effecting space time, say one bolt struck nearer to a heavy gravity body, then you could still put her life on the line against her perspective.
@Laughingblades And what if we put her in a bigger space train? A really, really big space train - as large as a planet? We can even put some mountains and rivers inside her huge ass train, maybe even a small train station, like the one in this clip.
Then we run the experiment once more, and again she sees the front flash before the back flash. Are the flashes still simultaneous?
@Biarry Unless you're altering spacetime, then yes, but I'm not just dealing with the flashes, I'm dealing with the moments of impact. Though this experiment is a bad example.
Imagine two alarms on opposite ends of a hall, each on a timer synchronized with an atomic clock to ring at the exact same time. Now from a middle frame of reference they go off simultaneously, for the woman walking down the hall the nearest appears to go off first, only this time we can check the sincerity of the clocks.
:/ I was about to say that this was the best presentation on the Theory of Relativity I'd seen in awhile but then at the very end it fell into the same Copenhagen crap trap that Einstein rejected. Maybe you should take Albert Einstein's name off of this?
The observer in the train is objectively wrong, the frame of reference provides a misleading interpretation of events, relativity does deal with frames of reference but does not suggest that a paradox is true due to different reference points.
There is one flaw in this video. That is: The woman on the train WOULD see both lights at the same time. The problem is that the video stays in the platform observer's reference frame. It is correct in saying the platform observer would predict the woman would see the front light first HOWEVER, in her reference frame she would see them at the same time as she is equidistant from the light sources (in her reference frame she is not moving, and thus, not moving towards or away from either source).
I'm curious what would happen if this experiment was reversed? Say the passenger has a torch that can reflect light in two directions, directly forward and directly back with the press of a single button. And say there are sensors at the front and back of the train. I assume the bystander would see the light hit the back sensor first followed by the front. But how is this reconciled with the passenger who should have data from the sensors that show both arrived at the same time?
This is flawed- from the passenger's point of view (or any POV), d1 still ≠ d2 because d1 had to travel a longer distance to 'catch up' with the passenger while d2 had a much shorter distance because she was moving closer to d2's light source. Regardless, the passenger's POV is irrelevant because she's observing reality from the skewed perspective of being in motion. The lightning bolts hit at the same time regardless of how she observes it. If I am wrong, can someone explain it to me?
Another point to make: "... the passenger's POV is irrelevant because she's observing reality from the skewed perspective of being in motion." The whole point of relativity is that it is just as valid for her to claim that *she* is motionless and it is the train platform that is in motion; both POVs are equally valid and correct. There is no such thing as absolute rest -- all motion is measured relative to something else. (cont)
(cont) The odd bit is that, regardless of all of this relative motion, everyone measures *exactly the same value* for the speed of a beam of light. For *that* to be true (and it is), length and time must skew when observers are moving with respect to each other.
@DarthClam: From the passenger's point of view, if she is sitting in the middle of the train, from front to back, which is closer to her, the front of the train, or the back? How about when the train is moving? Is she closer to either the front or the back? In either case, she is equidistant from the front and the back, regardless of whether the train is moving. So, she will only see one strike first if it happened first, or otherwise both at the same time - regardless of the train's motion.
Time doesn't exist, exists only movement. If every atom stopped moving would you have time? No. Time is just a human idea to keep track of these atoms moving. That's why there is no substance in Relativity theory. If nobody can explain it with simple words after so many years there must be a reason why: there is nothing to understand. Einstein initially made a great discovery by proving the light bending effect during the eclipse. After that it was all media hype.
@myuncle2 thats a good point,.. but if there was no movement,.. then there would be no expansion,... that would mean no us,... i think that any way you cut it,.. there has to be a way of measurement for things to compare to,.. call it time,.. km,.. miles what ever ,...it docent really matter,... like the way i see it,.. LIGHT SPEED,.. thats a load of croc,..LIGHT,... can't move , we do and at a constant speed ,. leaving a trail of light, that we can see,.,...!!
And how would you even get two lightning bolts to hit at the same time? Do you just keep running the train in a circle and wait until you get lucky? :P
How would the guy know the light struck him at the same time? Wouldn't it of happened too fast to know? Also, how would the passenger even notice the flash from the back if she's facing forward? Especially if they were to strike at the same time, the light would reach the same places depending on certain aspects of the train. In this case she would be able to see the light in her eyes, and the light on the back of the seat in front of her, but who notices things like that in that amount of time?
@NewgroundsOwnSBB Well the person speaking in the video did not say the people were astronomically accurate light sensitive computers with astronomically accurate clocks.
@LeconsdAnalyse Okay, an observer, still nobody can look at both the lightning bolt in the front and the light from the lightning bolt on the rear of the seat placed in front of her. If she saw both, then they did not hit at the same time. I believe that was explained in the video though. Though can one lightning bolt stay longer than another? I believe so, correct me if i'm wrong.
the universal clock varies due to gravitational factors and our individual clocks varies due to awareness factors (if your a sleep time goes fast, if you sit there staring at the clock awake time goes slow).
But if you think about it, our time clock is different from the real universal clock, so there is varying perspectives which could lead to a massive paradigm shift on our perception of life. as individuals under our individual clock, time before our life did not exist relative to us.
Clever, but real-life answer: Woman has not got eyes in back of her head. So she would have to use her make up mirror to observe rear lightning strike. Speed of light in glass slower than in air + it has to travel further, thus creating impression of lightning strike on rear occurred 'after' strike on front. :-)
@legoliker123 Yes, but if you are on that train - it doesnt just appear that way - it actually is that way - for u it actually occurs b4 the second one for all intents and purposes - its not like they REALLY are simultaneous - coz the situation can the reversed and the station would be struck instead of the train and then both people would conclude the opposite sequences from the pov of the train guy.
Everything is relative. Size, time. In space, without a point of reference, it is literally impossible to tell whether your space craft is moving or if your friends is.
How are both correct? I understand how the perosn on the train percives something different to the stationary person, but...since the stationary person is stationary, isn't his perception the correct one?
@MartinTobinPham Imagine for a second that those lightning strikes actually delivered a blast of deadly radiation as well (which would also move at the speed of light, because that's what light is - radiation). The observer on the platform wouldn't just *perceive* simultaneous lightning, his body would actually be burned on each side at the same time. The girl on the train would be found to have been burned at two different times. Thus, this is not just an observer thing, it's physical, too.
@MartinTobinPham There is no correct one - coz for the person on the train, the person outside is moving. How would u know [if there were no bump] which was moving? The stationary person is stationary only compared to the earth. Hes moving for someone on the moon or the sun. Both are equally true - there is no 'really' in relativity. For the train guy person, he is stationary and the earth guy and the earth are moving backward - just as much as he is moving from the other guy's perspective.
@aaqucnaona94 Does the theory of relativity include a section on how to treat migraines? I'm sure they wouldn't mind a small one to help all us lamen's trying to catch up and understand at least the basics :-(
@MartinTobinPham what if this happened in space? Who's to say who is stationary. There is only relative motion. So just as the train is moving relative to the person on the platform, the person on the platform is moving relative to the person on the train. They are both stationary in their own frames of reference. You are using the ground as an absolute stationary position. That is not the case. Remember that you're standing on a planet that's revolving at 900 mph & orbiting at 90 mi/s...
A little knowledge of science makes man an atheist, but an in-depth study of science makes him a believer in God." - Francis Bacon.
"I can conceive how it might be possible for a man to look down upon the earth and be an atheist, but I cannot conceive how he could look up into the heavens and say there is no God." -- Abraham Lincoln
the video still does not anwser wether the simultanous jolts occured at the same time. in another word, in T0 which one is launched first, the right jolt or the left jolt.
@warrior4just " which one is launched first, the right jolt or the left jolt."
That's because it depends on the observer's frame of reference. That is the whole point. on the train depicted the right one was first. if there was another train going the opposite direction, an observer on that train would have the opposite answer.
i understand that. but i'm talking about at t0 in regardless of reference, it has to be that either at the same time, or one lags the other. correct me if i'm wrong in a clearer way
@warrior4just There is no t0 regardless of reference. there must be a frame of reference. They actually happen simultaneously for the observer on the side, and they actually happen at different times for people on the train. Both are accurate views of reality. The point is that there is no one correct way to see it. They are all correct.
what u said here i understood it. But there must be a time gradient 0 in which that either start differently or at the same time. because in there is one answer regardless of reference. time space referential is what makes the conclusion inconsistent and both correct. in the scheme of solving the problem of let say measuring arc power of each one of them delivered at shared point, but u want to idetify them based on time vector. how can u know which one is first ?
i live in IRELAND, and i found out they put fluoride in our water,.. !!! supposedly for our theeths health,.... but found out that its BANNED in europe as a POISON,... A HEAVEY METAL ,.. that causes slowed reactions and decreased IQ,..!!! ,... and the only countries that use it are AMERICA,...BRITAIN ,.... ( IRELAND ) AND AUSTRALIA!!!!!! soooo be cause or the relativity thing,... dose that explain,.. why we are dumber then europe,.. were just SLOWER :-)
@FLYGUYNO1 You are retarded. Fluoride is not in any way, shape or form a metal. Heavy or otherwise. Chlorine is poisonous. I assume you were thinking of it, although it is a completely different element. However, it isn't a metal either. Neither of them cause lower IQ or reactions times. Although I suppose if you inhale chlorine gas you will react slower because you will be dead, but that is beside the point.
@MrTiki95 ,... as well as the fact that europe has banned the use of fluoride,.. as it deems its use as medicating people against there free will,... its also a nuclear fuel derivative .. and by product,... that is what is added to the drinking water supple of ,.. TWO THERDS OF AMERICA,.. IRELAND AND AUSTRALIA.
@DrSamba1 do you think its makes me more intelligent if i can spell and write properly ,..!!! heres one for you,.. you have a watch on your hand right now,.. don't you,... see most people UNDER the age of 25,.. don't see them as necessary ,.... why use a watch when you got a phone,... or see it on tv,.. or in the street,..... do you know all the ABBREVIATIONS that young people know today,.. lol ,... i DOUGHT IT ,,.. but yet,.. you TRY to come across smart,... id buy and sell u mate
@FLYGUYNO1 If you had ever taken a grade 9 science class in which you learn about the periodic table of elements, you would realise that fluorine is categorised in the Non-metals category. It is in no way a heavy metal. Get your facts straight. Also, you will take in more fluorine from brushing your teeth once than drinking 100 big glasses of water. Imbecile.
@ScopedPewPew you had better stop brushing your teeth then,... lol imbecile,.....!!!!!! thats a big word for a MORON,.. did u find that all by your self,....!!!!!!! i could waste a few mins of my life trying to educate a fool ,.. but whats the point,... you'd still be a fool after it,... just , one with a bit of knowledge ,.. BUT grade 8,... thats like second year,.. here in IRELAND,.. and i thought we were slow,.. some advice,.. stop DRINKING WATER, ur sl,w enough.
lorentz! lorentz! this just proves that length contracts for the observer on the train, light MUST reach her at the same speed, the ONLY way it can happen is if the distance between train observer and front strike is shortened in her frame of reference, hence lorentz contraction and my word isnt this universe a freaky place to live??
@legoliker123 Actually, this video explains that from the perspective of the person ON the train, the front flash ACTUALLY happened first. The key idea in relativity is that no matter where you are and how fast you are, the speed of light is ALWAYS constant. Thus even if you shoot a light beam forward while moving at half the speed of light, a guy watching you pass would see the light you shoot ALSO moving at the SAME speed you see it moving.
Checkout "What if Einstein was wrong?" by ItsRainMakingTime on YouTube.
Dr. Peri Spolter (Ph.d, U. of Wisconsin) discusses her book "Gravitational Force of the Sun" in which she shows how Newton & Einstein did NOT use observational data but imaginary concepts that selectively use nature to fit the theory.
Accordingly, Newton ignored Kepler's 3rd law (actual gravitational force) which has no basis in mass. She also disclaims Einstein's concept of space/time, i.e. time as a 4th dimension.
The Lorentz transformation preserves simultaneity in relatively moving frames of reference, provided x = 0 (local event) at time t = 0. When separate calculations are made for each event, t' = 0 as well. The video applies only to calculations of remote events in the "other" frame, and is therefore a simple case of mathematical mirage.
@RebornMB Haha that is funny, because Einstein was religious. There is a myth going around that he wasn't, but that is not true. If you call religion stupid then you call one of Einstein's beliefs stupid. Which is more likely? Einstein made a mistake or you are a dumbass who has such a closed mind?
@Huntorkrunk I suppose it's even more funny that, to be precise, Einstein was believed in agnosticism.
To quote him: "I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it."
He in fact frowned upon the concept of personal God(s), which can be found in Christianity, Judaism, etc. (continues..)
@Huntorkrunk (...cont'd) Einstein despised he kind of religion that RebornMB refered to. According to him, a poor understanding of causality causes fear and the fearful invent supernatural beings, while the desire for love and support create a social and moral need for a supreme being.
Religion in itself IS stupid, whether you wish to believe that statement or not, and has no correlation whatsoever with what Einstein believed.
@Huntorkrunk (..cont'd) However, to quote him again, "Science without religion is lame, religion without science is blind".
There is no solid evidence that supports either side of the argument. Hence, we should not simply deny the existence of any diety, but at the same time, we should not blindly follow what our imagination percieves to be "true".
THIS is what people, including you and RebornMB, should at least try to understand rather than bash at each other with the so-called "evidence".
@Huntorkrunk No I just hate religion...I'm open to new ideas but after quite a few years I've realized religion isn't my thing. Sorry, I understand what you're trying to say though.
@RebornMB That's hilarious because I go to a catholic highschool and we actually have Biology, Chemistry, phsyics, etc as classes at the grade 11 and 12 level. God is not mentioned in any of them. In Biology I even learned about the theory of evolution, and my teacher himself said that the theory is very plausible. Did I mention he's also very deeply religious? Or how about the fact we're taking very basic quantum physics right now in chemistry to understand atoms and such.
@RebornMB All our science compared to reality is primitive and childlike.... if you have any insight at all, you would see that the world we live in was designed
@RebornMB I am christian, but i'm not saying that I think less of anyone who isn't, i'm just saying you should admit that it is very logical for science and creationism to coexist. There are many aspects of science that are very exact and cannot be explained by them happening by chance.
@dalli2 Wow! you must be some close minded person! completely closed.. not even a crack. a teenie tiny crack of light in your head!, your mind must be completely empty and dark! perhaps no common sense can even live in there! it's time for you to take of all your cloths and head back to the stone age and sit in cave. People like you still think the world is flat, and there's no such things as bones.
If you are a truth seeker, search "Truth Contest" in Google and click on the 1st result, then open The Present and read what it says. Everyone needs to see this. The Present will turn this world right-side up if it reaches enough people. You will see what I mean when you read the first page.
Surely both are wrong because the passenger canno deny the fact that a bolt of lightening hit the back of the train just becasue they didnt see it for fuck sake.
At about 0:45 the video shows the platform frame light bubbles expanding, but superimposed on the moving train. The front light bubble is shown expanding at speed c + v and the rear bubble is shown expanding at speed c - v relative to the train, which doesn't happen. In reality the bubbles expand at speed c within all frames, and from the ends of the train in that frame. Therefore the man's predictions are invalid, and simultaneity is absolute.
IF the dude sees the two ends of the train getting struck simultaneously, and IF he is equidistant from the two "spacetime" flash points, then the chick will also see them flash simultaneously. Just as the dude thinks he sees his light-bubbles intersecting the chick at different times, so the chick thinks she sees her light-bubbles intersecting the dude at different times. Absolute reciprocity thereby disproves the relativity of simultaneity.
@LeconsdAnalyse Niemals bin ich ärgerlich, ha ha. Seriously though, applying the Lorentz transformation to each end of the train individually, where t ' = γ(t - vx / c^2), it is seen that t ' = 0 when t = 0 and x = 0, because the origin is local with the event. The distant event yields an illusory number, just as it does in the case of length contraction. Only the local observation is accurate. Therefore simultaneity is preserved in both inertial frames.
IF the girl sees the front bolt before the rear, then obviously it struck the train before the rear. In this case, the light from the front flash traveled a greater distance to the guy in a greater time, and the light from the rear flash traveled a smaller distance in a smaller time to the guy, both flashes arriving at him simultaneously. This shows the fallacious nature of the relativity of simultaneity. The bolts were not simultaneous.
@LeconsdAnalyse Yes, that's what the video claims. But it is just as possible that the front strike happened, in absolute terms, before the rear strike, explaining why the woman sees this in her inertial frame, and also explaining why the man sees them simultaneously from his point of view on the platform. After all, the train will have moved some distance between the two strikes, allowing the two non-simultaneous pulses to arrive at his location simultaneously. Both observers can now agree.
Thanks LeconsdAnalyse: Yes, that's what the video shows. But consider, IF two platform observers with synchronized clocks are positioned arbitrarily close to the lightning strikes, then they too should record simultaneous strikes. If two more observers are positioned inside the train arbitrarily close to the strikes, then they should be able to synchronize their clocks with the platform frame as they pass the two other observers, whether or not either frame is contracted. What do they see?
@SuperMagnetizer On-board guys see that the front (or right) observers - one on the train and one on the platform - made the contact before the two in the back.
Why? Because to them the outside observers stand too close to each other (length contraction), and the train doesn't fit between the two of them.
Hi Biarry: To establish the unequivocally absolute nature of simultaneity, simply set up flash bulbs at each end of the train, light detector-clocks located immediately adjacent to the passing train in the trackside frame, and a trip-wire to activate the two flash bulbs simultaneously in the train frame. The light detector-clocks will absolutely record cross-frame simultaneity. Relativistic speeds are not necessary.
In the train reference frame the car could be longer than the platform. When the front bulb and the front detector are aligned the trip-wire simultaneously activates both flash bulbs - but the back of the train hasn't even reached the station, let alone the back detector.
The back detector receives a flash coming from the left before the back bulb aligns with it, so it must have been turned on before the front bulb. Simultaneity breaks again.
@Biarry Yes, I realize the problem of length contraction when attempting to establish actual simultaneity between separate inertial frames. But just as the platform could be too short for the train from the train's point of view, so could the train be too short for the platform from the platform's point of view. Both contractions are optical illusions, in my opinion. Neither frame contracts in reality.
@SuperMagnetizer So it's not just simultaneity you don't like about SR? I thought you understand the theory, but had problems accepting that there's no absolute time.
It's back to basics for you. Read the two postulates of SR. Then watch the clip at 0:26, but ignore the train. Then watch the clip at 1:12 but ignore the ground. It's not easy, but when you see it you will sh** bricks.
Another (non-trivial) consequence is that a system in equilibrium will not necessarily be in equilibrium in an alternative frame of reference.
ekorusoy 1 day ago
so are they saying that witness can never be trusted in court? xD
WaiWu 2 days ago
At 0:25 to 0:35, the video shows the train STOPPED but the light bubbles expanding toward the platform observer. This is NOT what really happens! In reality, the relative motion of the train past the man continues as the light bubbles expand toward the platform. The time he sees the strikes will therefore not be when they actually occurred.
SuperMagnetizer 4 days ago
The train supposed to stop at the platform!!!!
2008HongKong 1 week ago
great explanation, much better than other videos iv seen
klegendk18 1 week ago 3
Hehe...hehe....
LeconsdAnalyse 1 week ago
The basic concept of relativity...
mufc4everch 1 week ago
This is great, clears things up completly
mufc4everch 1 week ago
@mufc4everch What "..things.." ?
LeconsdAnalyse 1 week ago
please see my video on the theory of the relativity of simultaneity at 269cristo. you will find the assumption to lead to an impossible conclusion
269Cristo 2 weeks ago
so basically what they are saying is:
* 1 thing can happen at two times, depending on how you see it/
* The speed at which you are traveling only has influence if you are on it.
napoleon950 2 weeks ago
It is quite possible for the 2 flashes of light to take place at different times (as determined by all observers) and still be observed simultaneously on the platform and non-simultaneously aboard the train. Since each flash requires a non-zero time interval to occur, the average distance from the front flash to the platform will exceed the average distance from the rear flash, as the car moves forward, and they will therefore reach the platform simultaneously.
SuperMagnetizer 2 weeks ago
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LeconsdAnalyse 2 weeks ago
@93HaD93 The case you are talking about is the classical case, where the velocity of light obeys the Galilean velocity-composition law and the speed (relative to the road) of the light flying towards the front is c + u and towards the rear is c - u (u is the car speed relative to the road, and c is the light speed relative to the car). Therefore the front and the rear are stroken at the same time, both in the car and on the road, and simultaneity is absolute.
starnutente1 2 weeks ago
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@starnutente1 Thanks to you and to Leconsd so much. I am getting it.
Only another doubt. You say: "the speed (relative to the road) of the light flying towards the front is c + u and towards the rear is c - u (u is the car speed relative to the road, and c is the light speed relative to the car)".
Are they not u + c and u - c relative to the road?
93HaD93 2 weeks ago
are we on the assumption that she has eyes in the back of her head...that can see through a headrest...
buggyiscool 2 weeks ago
@buggyiscool yes
yoitsblang 2 weeks ago
they say that if you run around a tree with light speed guess u know what happens who knows hit like
TheDineshgm 3 weeks ago
This is part of the reason why the four gospel accounts are different aspects of the same events yet atheists claim contradiction......nope!!! If eyewitnesses say the exact same thing, verbatim, then they will be suspected of corroboration....they plotted their scheme...
EXALTEDDIRT 3 weeks ago
@93HaD93 Hello. It would then NOT be SR.
You are probably (?) thinking about a MATERIAL object moving with constant acceleration (non-inertial reference frame). This is allowed in SR since the `equivalence principle` allows this situation to be viewed as the material object at rest (once again an inertial reference frame) subject to an external gravitational field.
LeconsdAnalyse 3 weeks ago
240p...we meet again
inceale 3 weeks ago
One thing not mentioned is the speed of the train. Must probably be thousands of km/h to be noticeable.
pk22cm 4 weeks ago
if a light bulb at each end of a rapidly moving train were two turn on at exactly the same time, would the mid-point passenger see both at the same time? Would they be the same color?
jfreed27 1 month ago
@jfreed27 The bulbs must be the same color since the bulbs do not move relative to the passenger.
As for the first question - it depends on whose time you're talking about when you say "the bulbs turn on at the same time".
Biarry 4 weeks ago
Not if it an express train.
jfreed27 1 month ago
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LeconsdAnalyse 1 month ago
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LeconsdAnalyse 1 month ago
OOOOOOH it all makes sense now lol
therealjordiano 1 month ago
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LeconsdAnalyse 1 month ago
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iamTOTALLYredeemed 1 month ago
the reason why I don't get it is that we are referring to two different frames, one for the train and one for the platform. so my question is: in which frame does the lightnings strike?
medeste 1 month ago
@medeste Reference frames do not "own" the events so the answer is: lightnings do not strike in any particular frame, they strike in all of them.
Biarry 1 month ago
@Biarry sorry your answer don't help me much. I either have a problem with this concept or just its explanation.we explain doppler effect with that, we say that something that's in another frame and produces a sound does have doppler effect, but it just makes sense is the sound is in the frame away from me. if it belongs to both in the same way it does not make any sense (to me). the events HAVE to belong to some frame, if they don't, well frames does not make any sense to me.
medeste 1 month ago
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LeconsdAnalyse 1 month ago
no, einstein and the girl on the train are wrong! if the girl on the train looks to the back, she is actually looking into the past because all light coming from the back of the train has to travel a further distance than light coming from the front. just because we see something happen doesn't mean it's happening at that instant. when we look at the stars and the sun, do we see them as they are right now? no, we are looking into the past! same thing with the train.
leviatam 1 month ago
@leviatam also, the train would have to be traveling at close to the speed of light, which would mean its relativistic mass would be enormous and time is slowed down inside the train, however this is irrelevant to the scenario.
leviatam 1 month ago
nooooo my friend is on a train that just got hit by two bolts of lightning
taylor68sander 2 months ago
Claiming that flashes of light from a moving source reach an observer at the same time (0:24) is equivalent to claiming that flashes of light from a stationary source reach a moving observer at the same time. The only way this can happen is if the flashes happen at different times.
SuperMagnetizer 2 months ago
SHE CAN ONLY SEE THE FRONT FLASH BECAUSE SHE IS FACING FORWARD !!!
mrcaspiansea 2 months ago
@mrcaspiansea
She would see the rear flash by reflection.
iamTOTALLYredeemed 1 month ago
@mrcaspiansea
lol
haidar1144 1 month ago
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DUDIN3421 1 month ago
@mrcaspiansea You're an idiot.
DUDIN3421 1 month ago
so like, eveyrhitng we believe in is true?
stasisnu18 2 months ago
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LeconsdAnalyse 2 months ago
the man looks like John Travolta!!
arijeetanubis 2 months ago
Question for people who understand the physics of Relativity: would you please give constructive criticism on my video on whether Relativity is consistent with the Growing Block Universe Theory of Time? That would be awesome. Thanks.
PhilosophyAnimation 2 months ago
Isn't the train supposed to stop at the platform?
onewell1987 2 months ago 47
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LeconsdAnalyse 2 months ago
@onewell1987 If it goes under 50mph it explodes...
mrfluke2000 2 months ago
Being correct from a false frame of reference doesn't make one necessarily correct.
Laughingblades 2 months ago
@Laughingblades True, but the man stands on a planet. Planets definitely move so his frame of reference cannot possibly be "true".
One man realized a long time ago that - as long as it moves in a straight line at a constant speed - the movement of the planet (and the train) is irrelevant. There are no preferred ("false") frames of reference.
Biarry 2 months ago
@Biarry Yes but on that planet, when two bolts of lightning strike at the same time that's no longer a mere point of reference, the simultaneity of impact doesn't change just because of a faulty frame of reference, and human lives could be put on the line in an experiment like this to make the point.
Laughingblades 2 months ago
@Laughingblades Yes - for the people on that planet the strikes are simultaneous. For the people on board that train and any planet in the universe that (by pure chance) is standing still relative to the train the strikes are not simultaneous. We call this "special relativity".
And - since the special relativity is pretty much undisputed - I don't think we should put any human lives on the line here.
Biarry 2 months ago
@Biarry Then by this definition of special relativity you're only referring to people's perspectives.
Because the simultaneity of the strikes is not contingent on your point of observation, it's contingent on whether the electricity hits the object at the same time, unless there's some time altering phenomena taking place you could put lives on the line with this. Suppose the train were rigged to derail if the strikes were not simultaneous, the point of view of the passenger would be irrelevant
Laughingblades 2 months ago
@Laughingblades And what if there was no planet? No track, no station, no man?
The woman sits in the middle of her space train. She sees the front flash first, then the flash from the back. Are they still "objectively" simultaneous?
Biarry 2 months ago
@Biarry Her perspective still doesn't effect the simultaneity of events, unless some special condition were effecting space time, say one bolt struck nearer to a heavy gravity body, then you could still put her life on the line against her perspective.
I mean you may as well invoke Schrodinger's Box
Laughingblades 2 months ago
@Laughingblades And what if we put her in a bigger space train? A really, really big space train - as large as a planet? We can even put some mountains and rivers inside her huge ass train, maybe even a small train station, like the one in this clip.
Then we run the experiment once more, and again she sees the front flash before the back flash. Are the flashes still simultaneous?
Biarry 2 months ago
@Biarry Unless you're altering spacetime, then yes, but I'm not just dealing with the flashes, I'm dealing with the moments of impact. Though this experiment is a bad example.
Imagine two alarms on opposite ends of a hall, each on a timer synchronized with an atomic clock to ring at the exact same time. Now from a middle frame of reference they go off simultaneously, for the woman walking down the hall the nearest appears to go off first, only this time we can check the sincerity of the clocks.
Laughingblades 2 months ago
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Laughingblades 2 months ago
:/ I was about to say that this was the best presentation on the Theory of Relativity I'd seen in awhile but then at the very end it fell into the same Copenhagen crap trap that Einstein rejected. Maybe you should take Albert Einstein's name off of this?
The observer in the train is objectively wrong, the frame of reference provides a misleading interpretation of events, relativity does deal with frames of reference but does not suggest that a paradox is true due to different reference points.
Laughingblades 2 months ago
There is one flaw in this video. That is: The woman on the train WOULD see both lights at the same time. The problem is that the video stays in the platform observer's reference frame. It is correct in saying the platform observer would predict the woman would see the front light first HOWEVER, in her reference frame she would see them at the same time as she is equidistant from the light sources (in her reference frame she is not moving, and thus, not moving towards or away from either source).
JussWallaxe 2 months ago
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LeconsdAnalyse 2 months ago
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LeconsdAnalyse 2 months ago
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LeconsdAnalyse 2 months ago
I'm curious what would happen if this experiment was reversed? Say the passenger has a torch that can reflect light in two directions, directly forward and directly back with the press of a single button. And say there are sensors at the front and back of the train. I assume the bystander would see the light hit the back sensor first followed by the front. But how is this reconciled with the passenger who should have data from the sensors that show both arrived at the same time?
arnaldo35 2 months ago
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LeconsdAnalyse 2 months ago
This is flawed- from the passenger's point of view (or any POV), d1 still ≠ d2 because d1 had to travel a longer distance to 'catch up' with the passenger while d2 had a much shorter distance because she was moving closer to d2's light source. Regardless, the passenger's POV is irrelevant because she's observing reality from the skewed perspective of being in motion. The lightning bolts hit at the same time regardless of how she observes it. If I am wrong, can someone explain it to me?
DarthClam 3 months ago
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LeconsdAnalyse 3 months ago
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LeconsdAnalyse 3 months ago
@LeconsdAnalyse Ahhhh okay. Thanks for taking the time to explain
DarthClam 3 months ago
@DarthClam
Another point to make: "... the passenger's POV is irrelevant because she's observing reality from the skewed perspective of being in motion." The whole point of relativity is that it is just as valid for her to claim that *she* is motionless and it is the train platform that is in motion; both POVs are equally valid and correct. There is no such thing as absolute rest -- all motion is measured relative to something else. (cont)
pseudorandomly 2 months ago
@DarthClam
(cont) The odd bit is that, regardless of all of this relative motion, everyone measures *exactly the same value* for the speed of a beam of light. For *that* to be true (and it is), length and time must skew when observers are moving with respect to each other.
pseudorandomly 2 months ago
@DarthClam: From the passenger's point of view, if she is sitting in the middle of the train, from front to back, which is closer to her, the front of the train, or the back? How about when the train is moving? Is she closer to either the front or the back? In either case, she is equidistant from the front and the back, regardless of whether the train is moving. So, she will only see one strike first if it happened first, or otherwise both at the same time - regardless of the train's motion.
krulez03 2 months ago
finaly I understand what the theory of relativity is and what it means :)
Shadow31314 3 months ago
This has been flagged as spam show
Time doesn't exist, exists only movement. If every atom stopped moving would you have time? No. Time is just a human idea to keep track of these atoms moving. That's why there is no substance in Relativity theory. If nobody can explain it with simple words after so many years there must be a reason why: there is nothing to understand. Einstein initially made a great discovery by proving the light bending effect during the eclipse. After that it was all media hype.
myuncle2 3 months ago
@myuncle2 thats a good point,.. but if there was no movement,.. then there would be no expansion,... that would mean no us,... i think that any way you cut it,.. there has to be a way of measurement for things to compare to,.. call it time,.. km,.. miles what ever ,...it docent really matter,... like the way i see it,.. LIGHT SPEED,.. thats a load of croc,..LIGHT,... can't move , we do and at a constant speed ,. leaving a trail of light, that we can see,.,...!!
FLYGUYNO1 3 months ago
And how would you even get two lightning bolts to hit at the same time? Do you just keep running the train in a circle and wait until you get lucky? :P
DeepQantas 3 months ago
How would the guy know the light struck him at the same time? Wouldn't it of happened too fast to know? Also, how would the passenger even notice the flash from the back if she's facing forward? Especially if they were to strike at the same time, the light would reach the same places depending on certain aspects of the train. In this case she would be able to see the light in her eyes, and the light on the back of the seat in front of her, but who notices things like that in that amount of time?
VoguishArts 3 months ago
@VoguishArts assume that they're not humans but astronomically accurate light sensitive computers with astronomically accurate clocks
NewgroundsOwnSBB 3 months ago
@NewgroundsOwnSBB Well the person speaking in the video did not say the people were astronomically accurate light sensitive computers with astronomically accurate clocks.
VoguishArts 3 months ago
@VoguishArts assume that they're superman
NewgroundsOwnSBB 3 months ago
@NewgroundsOwnSBB Why not superwoman? I'm finding a little discrimination being shown.
VoguishArts 3 months ago
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LeconsdAnalyse 3 months ago
@LeconsdAnalyse Okay, an observer, still nobody can look at both the lightning bolt in the front and the light from the lightning bolt on the rear of the seat placed in front of her. If she saw both, then they did not hit at the same time. I believe that was explained in the video though. Though can one lightning bolt stay longer than another? I believe so, correct me if i'm wrong.
VoguishArts 3 months ago
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LeconsdAnalyse 3 months ago
@LeconsdAnalyse Yes, that was said in the video above. What I mean is, do both lightning bolts have the same time lapse cloud-to-train?
VoguishArts 3 months ago
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LeconsdAnalyse 3 months ago
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LeconsdAnalyse 3 months ago
the universal clock varies due to gravitational factors and our individual clocks varies due to awareness factors (if your a sleep time goes fast, if you sit there staring at the clock awake time goes slow).
But if you think about it, our time clock is different from the real universal clock, so there is varying perspectives which could lead to a massive paradigm shift on our perception of life. as individuals under our individual clock, time before our life did not exist relative to us.
deanmullen10 3 months ago
Clever, but real-life answer: Woman has not got eyes in back of her head. So she would have to use her make up mirror to observe rear lightning strike. Speed of light in glass slower than in air + it has to travel further, thus creating impression of lightning strike on rear occurred 'after' strike on front. :-)
HughFromAlice 3 months ago
@legoliker123 Yes, but if you are on that train - it doesnt just appear that way - it actually is that way - for u it actually occurs b4 the second one for all intents and purposes - its not like they REALLY are simultaneous - coz the situation can the reversed and the station would be struck instead of the train and then both people would conclude the opposite sequences from the pov of the train guy.
aaqucnaona94 3 months ago
Everything is relative. Size, time. In space, without a point of reference, it is literally impossible to tell whether your space craft is moving or if your friends is.
AroundSun 3 months ago
Difference between perspectives is caused by the movement of the train- it is moving toward the front bolt, lessening the distance.
imranhamid99 3 months ago
How are both correct? I understand how the perosn on the train percives something different to the stationary person, but...since the stationary person is stationary, isn't his perception the correct one?
MartinTobinPham 3 months ago
@MartinTobinPham Imagine for a second that those lightning strikes actually delivered a blast of deadly radiation as well (which would also move at the speed of light, because that's what light is - radiation). The observer on the platform wouldn't just *perceive* simultaneous lightning, his body would actually be burned on each side at the same time. The girl on the train would be found to have been burned at two different times. Thus, this is not just an observer thing, it's physical, too.
Econniff 3 months ago
@Econniff Very clever, thanks for sharing that thought!
Gulzt 3 months ago
@MartinTobinPham
Neither one is more correct since there is no such thing as "stationary". The person on the train sees the observer as moving.
1234321jack 3 months ago
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LeconsdAnalyse 3 months ago
@MartinTobinPham There is no correct one - coz for the person on the train, the person outside is moving. How would u know [if there were no bump] which was moving? The stationary person is stationary only compared to the earth. Hes moving for someone on the moon or the sun. Both are equally true - there is no 'really' in relativity. For the train guy person, he is stationary and the earth guy and the earth are moving backward - just as much as he is moving from the other guy's perspective.
aaqucnaona94 3 months ago
@aaqucnaona94 Does the theory of relativity include a section on how to treat migraines? I'm sure they wouldn't mind a small one to help all us lamen's trying to catch up and understand at least the basics :-(
chicarbiomed 3 months ago
@MartinTobinPham what if this happened in space? Who's to say who is stationary. There is only relative motion. So just as the train is moving relative to the person on the platform, the person on the platform is moving relative to the person on the train. They are both stationary in their own frames of reference. You are using the ground as an absolute stationary position. That is not the case. Remember that you're standing on a planet that's revolving at 900 mph & orbiting at 90 mi/s...
Bozeman42 3 months ago
How can this not be a paradox?
Danielson761729 3 months ago
@Danielson761729 Because it is Reality.
gregrutz 3 months ago
A little knowledge of science makes man an atheist, but an in-depth study of science makes him a believer in God." - Francis Bacon.
"I can conceive how it might be possible for a man to look down upon the earth and be an atheist, but I cannot conceive how he could look up into the heavens and say there is no God." -- Abraham Lincoln
zotje11 3 months ago
@legoliker123 yes
FLYGUYNO1 3 months ago
:-o
FLYGUYNO1 3 months ago
the video still does not anwser wether the simultanous jolts occured at the same time. in another word, in T0 which one is launched first, the right jolt or the left jolt.
warrior4just 3 months ago
@warrior4just " which one is launched first, the right jolt or the left jolt."
That's because it depends on the observer's frame of reference. That is the whole point. on the train depicted the right one was first. if there was another train going the opposite direction, an observer on that train would have the opposite answer.
Bozeman42 3 months ago
@Bozeman42
i understand that. but i'm talking about at t0 in regardless of reference, it has to be that either at the same time, or one lags the other. correct me if i'm wrong in a clearer way
warrior4just 3 months ago
@warrior4just There is no t0 regardless of reference. there must be a frame of reference. They actually happen simultaneously for the observer on the side, and they actually happen at different times for people on the train. Both are accurate views of reality. The point is that there is no one correct way to see it. They are all correct.
Bozeman42 3 months ago
@Bozeman42
what u said here i understood it. But there must be a time gradient 0 in which that either start differently or at the same time. because in there is one answer regardless of reference. time space referential is what makes the conclusion inconsistent and both correct. in the scheme of solving the problem of let say measuring arc power of each one of them delivered at shared point, but u want to idetify them based on time vector. how can u know which one is first ?
warrior4just 3 months ago
if you think about it, its kinda obvious
ClanChattan14 4 months ago
i live in IRELAND, and i found out they put fluoride in our water,.. !!! supposedly for our theeths health,.... but found out that its BANNED in europe as a POISON,... A HEAVEY METAL ,.. that causes slowed reactions and decreased IQ,..!!! ,... and the only countries that use it are AMERICA,...BRITAIN ,.... ( IRELAND ) AND AUSTRALIA!!!!!! soooo be cause or the relativity thing,... dose that explain,.. why we are dumber then europe,.. were just SLOWER :-)
FLYGUYNO1 4 months ago
@FLYGUYNO1 You are retarded. Fluoride is not in any way, shape or form a metal. Heavy or otherwise. Chlorine is poisonous. I assume you were thinking of it, although it is a completely different element. However, it isn't a metal either. Neither of them cause lower IQ or reactions times. Although I suppose if you inhale chlorine gas you will react slower because you will be dead, but that is beside the point.
MrTiki95 3 months ago
@MrTiki95 ,... as well as the fact that europe has banned the use of fluoride,.. as it deems its use as medicating people against there free will,... its also a nuclear fuel derivative .. and by product,... that is what is added to the drinking water supple of ,.. TWO THERDS OF AMERICA,.. IRELAND AND AUSTRALIA.
FLYGUYNO1 3 months ago
@FLYGUYNO1
1. Learn to spell "third" and "supply".
2. It's "their" free will, not "there" free will.
3. "Its" is the possessive third person singular neuter; "it's" is a contraction for "it is."
4. I won't even get mention the capitalization.
DrSamba1 3 months ago
@DrSamba1 do you think its makes me more intelligent if i can spell and write properly ,..!!! heres one for you,.. you have a watch on your hand right now,.. don't you,... see most people UNDER the age of 25,.. don't see them as necessary ,.... why use a watch when you got a phone,... or see it on tv,.. or in the street,..... do you know all the ABBREVIATIONS that young people know today,.. lol ,... i DOUGHT IT ,,.. but yet,.. you TRY to come across smart,... id buy and sell u mate
FLYGUYNO1 3 months ago
@FLYGUYNO1
1. It's DOUBT not DOUGHT.
2. No, I don't wear a watch.
3. Spelling and writing properly doesn't make you more intelligent, but spelling and writing improperly makes you appear like a blithering idiot.
4. I don't give a rat's ass about the abbreviations that young people know today. It is still the English language.
5. Yes, I am smart.
DrSamba1 3 months ago
@FLYGUYNO1 If you had ever taken a grade 9 science class in which you learn about the periodic table of elements, you would realise that fluorine is categorised in the Non-metals category. It is in no way a heavy metal. Get your facts straight. Also, you will take in more fluorine from brushing your teeth once than drinking 100 big glasses of water. Imbecile.
ScopedPewPew 3 months ago
@ScopedPewPew you had better stop brushing your teeth then,... lol imbecile,.....!!!!!! thats a big word for a MORON,.. did u find that all by your self,....!!!!!!! i could waste a few mins of my life trying to educate a fool ,.. but whats the point,... you'd still be a fool after it,... just , one with a bit of knowledge ,.. BUT grade 8,... thats like second year,.. here in IRELAND,.. and i thought we were slow,.. some advice,.. stop DRINKING WATER, ur sl,w enough.
FLYGUYNO1 3 months ago
science is sexy
omgitsaghiles 4 months ago
mind blown :)
Wh1skey 4 months ago
so according to the theory of relativity... what exactly is happening here?
vpsjdon 4 months ago
what a boss
sniperdude5236 4 months ago
lorentz! lorentz! this just proves that length contracts for the observer on the train, light MUST reach her at the same speed, the ONLY way it can happen is if the distance between train observer and front strike is shortened in her frame of reference, hence lorentz contraction and my word isnt this universe a freaky place to live??
BedfordBears 4 months ago
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LeconsdAnalyse 4 months ago
this was the last question on physics exam
rlui123 4 months ago
@legoliker123 Actually, this video explains that from the perspective of the person ON the train, the front flash ACTUALLY happened first. The key idea in relativity is that no matter where you are and how fast you are, the speed of light is ALWAYS constant. Thus even if you shoot a light beam forward while moving at half the speed of light, a guy watching you pass would see the light you shoot ALSO moving at the SAME speed you see it moving.
joejoejoe532 4 months ago
@12 sec, I think all he was thinking about was how hot she was :-)
codednines 4 months ago
1.21 GigaWatts
Iriatv 5 months ago 5
@Iriatv that was just born to be a top comment.
darthkahn45 4 months ago
This video did not actually explain the concept but merely asserted it. Try again.
hznfrst 5 months ago
Checkout "What if Einstein was wrong?" by ItsRainMakingTime on YouTube.
Dr. Peri Spolter (Ph.d, U. of Wisconsin) discusses her book "Gravitational Force of the Sun" in which she shows how Newton & Einstein did NOT use observational data but imaginary concepts that selectively use nature to fit the theory.
Accordingly, Newton ignored Kepler's 3rd law (actual gravitational force) which has no basis in mass. She also disclaims Einstein's concept of space/time, i.e. time as a 4th dimension.
bondurango 5 months ago
The Lorentz transformation preserves simultaneity in relatively moving frames of reference, provided x = 0 (local event) at time t = 0. When separate calculations are made for each event, t' = 0 as well. The video applies only to calculations of remote events in the "other" frame, and is therefore a simple case of mathematical mirage.
SuperMagnetizer 5 months ago
@dalli2 Too stupid to understand science? Try religion
RebornMB 5 months ago 90
@RebornMB Lmfao. I love you.
41354N4 5 months ago
@RebornMB lol, nice
lightitupfool 5 months ago
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SenolisFromV 5 months ago
@RebornMB Haha that is funny, because Einstein was religious. There is a myth going around that he wasn't, but that is not true. If you call religion stupid then you call one of Einstein's beliefs stupid. Which is more likely? Einstein made a mistake or you are a dumbass who has such a closed mind?
Huntorkrunk 4 months ago
@Huntorkrunk I suppose it's even more funny that, to be precise, Einstein was believed in agnosticism.
To quote him: "I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it."
He in fact frowned upon the concept of personal God(s), which can be found in Christianity, Judaism, etc. (continues..)
Shadowerth 4 months ago
@Huntorkrunk (...cont'd) Einstein despised he kind of religion that RebornMB refered to. According to him, a poor understanding of causality causes fear and the fearful invent supernatural beings, while the desire for love and support create a social and moral need for a supreme being.
Religion in itself IS stupid, whether you wish to believe that statement or not, and has no correlation whatsoever with what Einstein believed.
(continues...)
Shadowerth 4 months ago
@Huntorkrunk (..cont'd) However, to quote him again, "Science without religion is lame, religion without science is blind".
There is no solid evidence that supports either side of the argument. Hence, we should not simply deny the existence of any diety, but at the same time, we should not blindly follow what our imagination percieves to be "true".
THIS is what people, including you and RebornMB, should at least try to understand rather than bash at each other with the so-called "evidence".
Shadowerth 4 months ago
@Huntorkrunk No I just hate religion...I'm open to new ideas but after quite a few years I've realized religion isn't my thing. Sorry, I understand what you're trying to say though.
RebornMB 4 months ago
@RebornMB
Science without religion is lame, religion without science is blind.
-Albert Einstein
Electroposit 4 months ago
@RebornMB That's hilarious because I go to a catholic highschool and we actually have Biology, Chemistry, phsyics, etc as classes at the grade 11 and 12 level. God is not mentioned in any of them. In Biology I even learned about the theory of evolution, and my teacher himself said that the theory is very plausible. Did I mention he's also very deeply religious? Or how about the fact we're taking very basic quantum physics right now in chemistry to understand atoms and such.
ScopedPewPew 3 months ago
@ScopedPewPew Okay. Look at the persons comment I replied to in the first place.
RebornMB 3 months ago
@RebornMB That should be a bumper sticker. :-D
chicarbiomed 3 months ago
@RebornMB All our science compared to reality is primitive and childlike.... if you have any insight at all, you would see that the world we live in was designed
wavsunlimited 3 months ago
@wavsunlimited Are you a christian? If not, what type of 'designer' do you believe in? Please explain in detail.
RebornMB 3 months ago
@RebornMB I am christian, but i'm not saying that I think less of anyone who isn't, i'm just saying you should admit that it is very logical for science and creationism to coexist. There are many aspects of science that are very exact and cannot be explained by them happening by chance.
wavsunlimited 3 months ago
What a load of tosh.
dalli2 5 months ago
@dalli2 Wow! you must be some close minded person! completely closed.. not even a crack. a teenie tiny crack of light in your head!, your mind must be completely empty and dark! perhaps no common sense can even live in there! it's time for you to take of all your cloths and head back to the stone age and sit in cave. People like you still think the world is flat, and there's no such things as bones.
ujayet 5 months ago
This has been flagged as spam show
If you are a truth seeker, search "Truth Contest" in Google and click on the 1st result, then open The Present and read what it says. Everyone needs to see this. The Present will turn this world right-side up if it reaches enough people. You will see what I mean when you read the first page.
SeekTruthN0w 5 months ago
fml
Jacob1giro 5 months ago 16
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leinad580 3 months ago
Surely both are wrong because the passenger canno deny the fact that a bolt of lightening hit the back of the train just becasue they didnt see it for fuck sake.
MCDEVVOMAN 5 months ago
Does that not mean that both are wrong?? If the bolts of Lightening were at different speeds??
MCDEVVOMAN 5 months ago
At about 0:45 the video shows the platform frame light bubbles expanding, but superimposed on the moving train. The front light bubble is shown expanding at speed c + v and the rear bubble is shown expanding at speed c - v relative to the train, which doesn't happen. In reality the bubbles expand at speed c within all frames, and from the ends of the train in that frame. Therefore the man's predictions are invalid, and simultaneity is absolute.
SuperMagnetizer 5 months ago
IF the dude sees the two ends of the train getting struck simultaneously, and IF he is equidistant from the two "spacetime" flash points, then the chick will also see them flash simultaneously. Just as the dude thinks he sees his light-bubbles intersecting the chick at different times, so the chick thinks she sees her light-bubbles intersecting the dude at different times. Absolute reciprocity thereby disproves the relativity of simultaneity.
SuperMagnetizer 5 months ago
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LeconsdAnalyse 5 months ago
@LeconsdAnalyse Niemals bin ich ärgerlich, ha ha. Seriously though, applying the Lorentz transformation to each end of the train individually, where t ' = γ(t - vx / c^2), it is seen that t ' = 0 when t = 0 and x = 0, because the origin is local with the event. The distant event yields an illusory number, just as it does in the case of length contraction. Only the local observation is accurate. Therefore simultaneity is preserved in both inertial frames.
SuperMagnetizer 5 months ago
parallel worlds in one world
gregorizi 5 months ago
parallel vords
gregorizi 5 months ago
TITS OR GTFO
afurmanpaladin 5 months ago
IF the girl sees the front bolt before the rear, then obviously it struck the train before the rear. In this case, the light from the front flash traveled a greater distance to the guy in a greater time, and the light from the rear flash traveled a smaller distance in a smaller time to the guy, both flashes arriving at him simultaneously. This shows the fallacious nature of the relativity of simultaneity. The bolts were not simultaneous.
SuperMagnetizer 6 months ago
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LeconsdAnalyse 6 months ago
@LeconsdAnalyse Yes, that's what the video claims. But it is just as possible that the front strike happened, in absolute terms, before the rear strike, explaining why the woman sees this in her inertial frame, and also explaining why the man sees them simultaneously from his point of view on the platform. After all, the train will have moved some distance between the two strikes, allowing the two non-simultaneous pulses to arrive at his location simultaneously. Both observers can now agree.
SuperMagnetizer 5 months ago
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LeconsdAnalyse 5 months ago
Thanks LeconsdAnalyse: Yes, that's what the video shows. But consider, IF two platform observers with synchronized clocks are positioned arbitrarily close to the lightning strikes, then they too should record simultaneous strikes. If two more observers are positioned inside the train arbitrarily close to the strikes, then they should be able to synchronize their clocks with the platform frame as they pass the two other observers, whether or not either frame is contracted. What do they see?
SuperMagnetizer 5 months ago
@SuperMagnetizer On-board guys see that the front (or right) observers - one on the train and one on the platform - made the contact before the two in the back.
Why? Because to them the outside observers stand too close to each other (length contraction), and the train doesn't fit between the two of them.
Biarry 5 months ago
Hi Biarry: To establish the unequivocally absolute nature of simultaneity, simply set up flash bulbs at each end of the train, light detector-clocks located immediately adjacent to the passing train in the trackside frame, and a trip-wire to activate the two flash bulbs simultaneously in the train frame. The light detector-clocks will absolutely record cross-frame simultaneity. Relativistic speeds are not necessary.
SuperMagnetizer 5 months ago
@SuperMagnetizer The key is the length contraction.
In the train reference frame the car could be longer than the platform. When the front bulb and the front detector are aligned the trip-wire simultaneously activates both flash bulbs - but the back of the train hasn't even reached the station, let alone the back detector.
The back detector receives a flash coming from the left before the back bulb aligns with it, so it must have been turned on before the front bulb. Simultaneity breaks again.
Biarry 5 months ago
@Biarry Yes, I realize the problem of length contraction when attempting to establish actual simultaneity between separate inertial frames. But just as the platform could be too short for the train from the train's point of view, so could the train be too short for the platform from the platform's point of view. Both contractions are optical illusions, in my opinion. Neither frame contracts in reality.
SuperMagnetizer 5 months ago
@SuperMagnetizer So it's not just simultaneity you don't like about SR? I thought you understand the theory, but had problems accepting that there's no absolute time.
It's back to basics for you. Read the two postulates of SR. Then watch the clip at 0:26, but ignore the train. Then watch the clip at 1:12 but ignore the ground. It's not easy, but when you see it you will sh** bricks.
Biarry 5 months ago