Today Special Relativity dies

[wespe]

well that IS what it says.

I'm sorry Ram, I can't communicate with you either.

It does NOT say "experimental set up is such that .. those events happen simultaneously in the absolute sense for both frames" as Eyesaw claims. It says the opposite.

Nice that you now corrected your diagram. Hope someone helps you with that. If not, you could try another forum.

 

[ram1024]

i'll break it down into parts with my translations, tell me where i go wrong.

When we say that the lightning strokes A and B are simultaneous with respect to the embankment, we mean: the rays of light emitted at the places A and B, where the lightning occurs, meet each other at the mid-point M of the length A —> B of the embankment

.

Observers taking the Embankment as a reference frame <stationary> will see that light from A and B hit M mid-point simultaneously

But the events A and B also correspond to positions A and B on the train. Let M' be the mid-point of the distance A —> B on the traveling train. Just when the flashes 1 of lightning occur, this point M' naturally coincides with the point M, but it moves towards the right in the diagram with the velocity v of the train

Assigning a point M' for the train reference frame such that at the precise instant any first flash of lightning hits "anywhere" M' coincides with M perfectly.

If an observer sitting in the position M’ in the train did not possesses this velocity, then he would remain permanently at M, and the light rays emitted by the flashes of lightning A and B would reach him simultaneously, i.e. they would meet just where he is situated

If he didn't make any relative motion in relation to the embankment he would receive simultaneous light just as the embankment viewers.

Now in reality (considered with reference to the railway embankment) he is hastening towards the beam of light coming from B, whilst he is riding on ahead of the beam of light coming from A. Hence the observer will see the beam of light emitted from B earlier than he will see that emitted from A.

Reality is defined as REAL motion being made TOWARDS target light B and AWAY from target light A. Naturally this follows that he will see light B before light A.

Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash B took place earlier than the lightning flash A.

BUT if he takes his own reference frame as stationary, to him light would have to cover the SAME DISTANCES to reach him, but yet he receives light in staggered intervals. since light speed is constant, and the distances are the same <because he measures the distances in HIS frame (not including the distances he traveled in the embankment frame) he MUST conclude that God didn't turn the lights on at the same time.

<end interpretation>

 

[geistkiesel]

i'll break it down into parts with my translations, tell me where i go wrong.

.

Observers taking the Embankment as a reference frame <stationary> will see that light from A and B hit M mid-point simultaneously



Assigning a point M' for the train reference frame such that at the precise instant any first flash of lightning hits "anywhere" M' coincides with M perfectly.



If he didn't make any relative motion in relation to the embankment he would receive simultaneous light just as the embankment viewers.



Reality is defined as REAL motion being made TOWARDS target light B and AWAY from target light A. Naturally this follows that he will see light B before light A.



BUT if he takes his own reference frame as stationary, to him light would have to cover the SAME DISTANCES to reach him, but yet he receives light in staggered intervals. since light speed is constant, and the distances are the same <because he measures the distances in HIS frame (not including the distances he traveled in the embankment frame) he MUST conclude that God didn't turn the lights on at the same time.

<end interpretation>

Yes, in a sense. Here Einstein concludes that the mere fact that the moving observer measures the photon arrival at staggered intervals that the passengers on the train "must, therefore come to the conclusion" the photons were not emitted simultaneously in the moving frame. If this is true, your God solution fits the glove like a hand.

And are you familiar with the study that showed the differences in praying practices performed by persons praying in chrches versus those praying in gambling casinos?
The gamblers really mean it!

 

[geistkiesel]

Einstein's gedanken corresponds to your case#3. The moving observer does not see the lightenings at the same time (since they occurred simultaneously in the stationary frame, they can't have occurred simultaneously in the train frame). I am 100% sure this is SR's prediction. Plus, if he saw them at the same time, there would be a paradox, because the non-moving midpoint observer sees them at the same time at another point in space.

Your 100% assurance is not correct.

AE did not invoke SR to come to his conclusion. You are bootstrapping, it is called circuitous reasoning. AE came to the conclusion that because the B photon was detected before the A photon was detected that this alone is why the passengers "must therefore come to the conclusion" that the photons were not emitted simultaneously in the moving frame. Any SR imperatives, even if applicable and they aren't, would be swamped by the time difference between the time the B and A photon were detected. Ene Doc Al agrees with this.

But if you make the moving observer stationary, of course he sees the lightenings at the same time, because he would be in the stationary frame now. That would correspond to case#1.

I don't understand why you say "midpoint DOES move". The midpoint of events never move within any frame, because the location of events never move within a frame. Location of an event in a frame may look like moving from another frame (like burning marks on the train as seen from the embankement), but they would move at the same speed as the train.



For the hundreth time, there is no motion of the observer in the observer's frame, observer is at rest wrt itself. Of course separation speed changes when looked from another frame, but that's irrelevant. What changes in a frame is the simultaneity of events, not how light moves. That's the whole point you are missing.

Looking at these probkem by stopping one frame and moving another is grossly and physically impossible. Where do you get justification for this? Do you kinow? It is from hand me down mathematics isn't it?

This is not a photon problem. As stated above AE came tot he conclusion he diod based purely on the fact the B photon was detected earlier than the A photon. But AE did not discuss passengers at a and b located at A and B just as the photons were emitted and ercorded the train time of the events. The a and b clock are synchribnized wrt the moving frame. This inoformation senet immediately tio O' will arrive just as the A photon arrives. Also, observers loated at M just as the photons A and B arrived at M also record the time of arrival and send thir tiems tio O'. O' now has the arival time of A, the recorded times of the A and B emissions from a and b, and the recorded time the photons arrived simultaneously at M in the stationary frame. The clock information is convincing that the photons arrived in the moving frame simultaneously as measured by twp sets of passengers. Likewise, O' can calculate the simultaneity himself. After a little algebra,

t3 = t1(C + v)/(C - v).

Draw your own time and distance map, this is what you will get, if you keep SR out of the gthe picture, or even if you insist SR will be swamped. Try it out.

t1 is the time of arrival of the B photons measured from when the O' observer was at the midpoint M when the photons were emitted and v the known velocity of the train. t3 is also a measured quantity the time the A photon was detected by O'. calculation can determine the accuracy of the measured vs. calculated time t3.

Again SR affects, if any, will be swamped by the staggered times of the B and A photon arrival.

 

[Doc Al]

Your 100% assurance is not correct.

AE did not invoke SR to come to his conclusion. You are bootstrapping, it is called circuitous reasoning. AE came to the conclusion that because the B photon was detected before the A photon was detected that this alone is why the passengers "must therefore come to the conclusion" that the photons were not emitted simultaneously in the moving frame. Any SR imperatives, even if applicable and they aren't, would be swamped by the time difference between the time the B and A photon were detected. Ene Doc Al agrees with this.

Nonsense. The reasoning that Einstein uses in the train gedanken is SR in action, my friend. What Einstein invokes is the invariant speed of light: a key premise of SR. And what he concludes--The relativity of simultaneity--is a key result of SR.

And what are you babbling about SR "imperatives" being swamped by time differences? (Do you seriously think I agree with this gibberish?)

You, geistkiesel, are the true master of circular reasoning.

 

[geistkiesel]

Let me clarify.

The "moving" observer in Einstein Gedanken is M'. When the lightenings strike, M' is at the midpoint according to the embankement. M' then moves to the right, according to the embankement.

Correct so far.

[quote =wespe]Now, according to M', the lightenings don't strike simultaneously. So, when looking from M' frame, we can't actually say "M' was at the midpoint when the lightenings stroke", because that's not a single instant.[/quote]
Wrong, even from SR theory.

What is being measured is "events simultaneous in the staionary frame are not simultaneous in the moving frame". When M' was at M, the midpoint when the photons were emitted simultaneously does not allow the moving observer to say the moving iobserver was not at M when the photons were emitted simultaneously.This is a given, remember, you can't change the givesn. You can add observers, measuring equipment and the like, but changiong the giovens is a no no. This is one problem that SR invokes when "considering a moving frame stationary, a physical impossibility.

The moving observer concludes the photons were not emitted simultaneously, not from SR theory, but from the simple staggered measurement of the photons, first B then A, nothing else. SR follows this, it does not precede this experiment. You are close to being there.

But we can say "M' was at the midpoint of the locations where the lightenings stroke". Those locations are where the burning marks are made on the train (not the embankement, we are in the train frame now). Then, M' does not move anywhere (in his own frame, according to himself), thus remains at the midpoint of the events the whole time.

About your case #7 (post#249, took some time to find), all observers remain at the same distance from the location of any emitted photons (in accordance to what I wrote above). In other words, the location any event never changes *within a frame*. The event has happened at an instant and its location cannot be carried with the source of the event or whatever.[/QUOTE]

 

[geistkiesel]

Let me clarify.

The "moving" observer in Einstein Gedanken is M'. When the lightenings strike, M' is at the midpoint according to the embankement. M' then moves to the right, according to the embankement.

Correct so far.

Now, according to M', the lightenings don't strike simultaneously. So, when looking from M' frame, we can't actually say "M' was at the midpoint when the lightenings stroke", because that's not a single instant.

Wrong, even from SR theory. M' concludes the lighning doesn't strike simultaneously only from his staggered measurement of the B and A photon, nothing else. Stick to the experiment. read it again befopre yopu start showing off your Sr theory knowledge, which has a nother day or two to survive and that is just becasue ram1024 is extending a proferssional courtesy.

What is being measured is "events simultaneous in the staionary frame are not simultaneous in the moving frame". When M' was at M, the midpoint when the photons were emitted simultaneously does not allow the moving observer to say the moving was not at M when the photons were emitted simultaneously.This is a given, remember, you can't change the given. You can add observers, measuring equipment and the like, but changing the givens is a no no. This is one problem that SR invokes when "considering" a moving frame stationary, a physical impossibility.

The moving observer concludes the photons were not emitted simultaneously, not from SR theory, but from the simple staggered measurement of the photons, first B then A, nothing else. SR follows this, it does not precede this experiment. You are close to being there.

But we can say "M' was at the midpoint of the locations where the lightenings stroke". Those locations are where the burning marks are made on the train (not the embankement, we are in the train frame now). Then, M' does not move anywhere (in his own frame, according to himself), thus remains at the midpoint of the events the whole time.

Maybe so, but the moving observer will still detect the B photon before the A photon. The experiment doesn't change.The light apeed deos not depend on the velocity of the source.

About your case #7 (post#249, took some time to find), all observers remain at the same distance from the location of any emitted photons (in accordance to what I wrote above). In other words, the location any event never changes *within a frame*. The event has happened at an instant and its location cannot be carried with the source of the event or whatever.

I suppose so.

 

[geistkiesel]

Let me clarify.

The "moving" observer in Einstein Gedanken is M'. When the lightenings strike, M' is at the midpoint according to the embankement. M' then moves to the right, according to the embankement.

Now, according to M', the lightenings don't strike simultaneously. So, when looking from M' frame, we can't actually say "M' was at the midpoint when the lightenings stroke", because that's not a single instant. But we can say "M' was at the midpoint of the locations where the lightenings stroke". Those locations are where the burning marks are made on the train (not the embankement, we are in the train frame now). Then, M' does not move anywhere (in his own frame, according to himself), thus remains at the midpoint of the events the whole time.

About your case #7 (post#249, took some time to find), all observers remain at the same distance from the location of any emitted photons (in accordance to what I wrote above). In other words, the location any event never changes *within a frame*. The event has happened at an instant and its location cannot be carried with the source of the event or whatever.

I brought the point up in response to another post of yours. The observer only determines the photons were not emitted simultaneously from the staggered detection of the B and A photons, nothing more or less. You cannot stop moving frame and consider the other moving. This is SR stuff. This problem is not SR. The staggered detection of the B and A photon will swamp any SFR aspects of the experiment, which there aren't any anyway.

 

[wespe]

OK, one more try for Geistkiesel:

Suppose we have two space-trains passing by each other. They are moving inertially, but we don't know which one had accelerated in the past. No experiment can determine which train is "really" moving. We only know that they have a relative speed wrt each other. Now, suppose two explosions is space occur near the trains (but not tied to any of the trains, just instant explosions, at any two times, we don't know yet). The explosions create burn marks on both trains.

SR's claim is: if there were two observers at the mid point of those burn marks (measured in each train separately), they could determine the simultaneity of the explosions according to their train, by looking at the order they see the explosions, because speed of light is constant and distances are the same.

Now, if one of the observers see the explosions at the same time, the other will not. Because, the burn marks and the midpoints on two trains will have a relative speed wrt each other, and therefore the light from the explosions cannot hit both observers at the same time.

So tell me, if one observer sees them at the same time, and both events were simultaneous in both frames, and speed of light is independent of its source, why won't the other see them at the same time? You can't use the excuse "the trains were moving" or "one of them was stationary", because then you assume aether, and then you can't determine simultaneity in any frame with this method without knowing speed wrt aether. Are you saying that simultaneity is affected by speed wrt aether? So what method can you tell me to determine if two events occurred simultaneously, if we can't determine speed of a frame wrt aether? (of course in fact there is no sign of aether whatsoever)

 

[geistkiesel]

Nonsense. The reasoning that Einstein uses in the train gedanken is SR in action, my friend. What Einstein invokes is the invariant speed of light: a key premise of SR. And what he concludes--The relativity of simultaneity--is a key result of SR.

No SR is the key result of simultaneity, read the history sir.

BS. NASCARS are running invariant in speed in my example and you ignored that example. Eintein does not use any SR postulate in arriving at his conclusion. He uses only the the staggrered arrival of theh B photon and A photon as detected by the O' observer. You have said on many occasions that this is what all agree.

quote Doc Al "The fact (agreed by all) the light from B hits O' before the light from A leads the O' observer to conclude the lights could not flash simultameously."

Which leg standeth thee on oh master mentor?

And what are you babbling about SR "imperatives" being swamped by time differences? (Do you seriously think I agree with this gibberish?)

You, geistkiesel, are the true master of circular reasoning.Quote:
Originally Posted by geistkiesel
I just came up with another proof that the moving observer must conclude the photons were emitted in the moving frame simultaneously with the emitted photons in the stationary frame.
Yeah, "another" one.

Let's cut through the nonsense, once again. Let's say a and b are the observers on the train located right next to the flashing lights at A and B when they flash. When the see the lights flash, they check the time. No need for any "relaying" of clock times anywhere. Assuming, like you did, that all clocks on the train are synchronized then--like it or not--observers a and b will record different times for the two photon emissions.

How do you know this? They must check the times they are on opposite ends of the train, but each immediately relay their findings to O' who receives the data along with the simultaneous observation of the A and B photons arriving at M simultaneously.

You are invoking SR time dilation and mass shrinking right? What else could you be invoking to make your statement that the observers at A and B will not record the same time of the emitted photons. The photons know nothing of SR theory or even that there are two observers dutifully recording the times the photons are emitted. the a and b observers record the same time.

Remember, what you said back in the Lost simultaneoity thread. let me remind you:
quote by Doc Al
"If you understood the Eisntein simple argument you would know that nowhere does "time dilation" or " mass shrinking" enter into it"

 

[geistkiesel]

Quote:
Originally Posted by Eyesaw
Actually my suggestion is that you try running from the burn marks on the track until you catch up to the observer inside the train and then tell us if there is a difference between running just from the burn marks on the train to the middle of the train.




Reread Einstein’s gendanken in his Special Relativity. The experimental set up is such that the rear and front of the train are located at A&B when the lightning flashes occur, i.e. those events happen simultaneously in the absolute sense for both the platform frame and the train frame. What is not simultaneous from one frame to the other are the reception of the signals from the events to the observers in the different frames. This however is hardly surprising since the train is moving towards one signal and away from the other signal when compared with the observer of the signals on the platform.

What is special about the platform frame is that since the observer is supposed to be at the midpoint of the flashes, she can only receive the signals simultaneously if she was really absolutely at rest- otherwise she would have to conclude that the speed of light measured from two different directions are not the same, contradicting the postulates of SR. So since an absolute rest frame was found it definitely makes life easier to measure all speeds relative to it. In reality the train experiment is of course flawed since the Earth is actually moving through space so that even the platform observer cannot receive the signals simultaneously.

But for amusement purposes, let’s assume that Einstein wasn’t talking about an absolute rest frame in his gedanken. It’s still absurd to use the reception time of signals as a representation of the sequence of how actual events occurred. If we see a star explode today from our telescope, who would be gullible enough to think that it happened today? So why do you make the case for relativity of simultaneity based on the reception time of the signals if in the absence of an absolute rest frame, it would be nigh impossible to determine the actual place in space when the light was produced nor our velocity through space, which surely must affect our determination of the speed of light since if the speed of light was truly constant in vacuo, if we have any motion through space, we will misjudge its true velocity. I don’t think this is a good reason to rid of absolute time do you? Really, which of you SR die hards can claim to have experienced any event that wasn’t absolutely simultaneous for everyone? If events were not absolutely simultaneous, your hand should have fell off from your wrist and your head from your body long before you finished typing your response.

Where in the hell have you been hiding?

 

[Eyesaw]

OK, one more try for Geistkiesel:

Suppose we have two space-trains passing by each other. They are moving inertially, but we don't know which one had accelerated in the past. No experiment can determine which train is "really" moving. We only know that they have a relative speed wrt each other. Now, suppose two explosions is space occur near the trains (but not tied to any of the trains, just instant explosions, at any two times, we don't know yet). The explosions create burn marks on both trains.

SR's claim is: if there were two observers at the mid point of those burn marks (measured in each train separately), they could determine the simultaneity of the explosions according to their train, by looking at the order they see the explosions, because speed of light is constant and distances are the same.

Now, if one of the observers see the explosions at the same time, the other will not. Because, the burn marks and the midpoints on two trains will have a relative speed wrt each other, and therefore the light from the explosions cannot hit both observers at the same time.

So tell me, if one observer sees them at the same time, and both events were simultaneous in both frames, and speed of light is independent of its source, why won't the other see them at the same time? You can't use the excuse "the trains were moving" or "one of them was stationary", because then you assume aether, and then you can't determine simultaneity in any frame with this method without knowing speed wrt aether. Are you saying that simultaneity is affected by speed wrt aether? So what method can you tell me to determine if two events occurred simultaneously, if we can't determine speed of a frame wrt aether? (of course in fact there is no sign of aether whatsoever)

Two trains have a relative speed. They both have burn marks on the front and rear and both observers are at the midpoint of their train. So if the speed of light is constant in vacuo how can either, or any observer for that matter, detect the explosion flashes simultaneously inside their own frame unless they were at absolute rest ? I'd like to hear your response on this point before I comment on the rest. I'm sure your response will involve a discussion about length contraction/time dilation so I'm curious how this will work. Seems to me that one half of the train should be contracted while the other half expanded for this to work, and how much contraction/expansion dependent on the frame observing the rest frame. Well, sorry but this sounds ridiculous.

 

[Eyesaw]

Another point I am confused with is this: if any inertial frame can consider themselves to be at the center of arbitrary emission events, doesn't that equate with the emitters of the light being at rest with respect to each inertial frame? If so, how can any inertial frame detect doppler shifting of light from two continuous emission sources? That is, if there is never any relative velocity between emission sources and the detection frame, how could light be doppler shifted in different inertial frames? Or if Doppler shifting of light was allowed, surely the observer that detects the flashes as non-simultaneous can deduce that his frame was in motion relative to the light emitters and hence the actual time of occurrence of the events?

 

[Eyesaw]

Where in the hell have you been hiding?

Well you and ram are tough acts to follow so I've basically been reading.

 

[ram1024]

heh, geist is scary. he'll be all quiet and calm for a week then BAM he'll jump in with a sledgehammer and hit you with pages worth of arguments.

 

[Eyesaw]

Geist writes very well, wish I can do that. Those defending SR here are also brilliant but they have a much more difficult task imo because they are trying to make something that is pretty nonsensical sound rational.

 

[geistkiesel]

Two trains have a relative speed. They both have burn marks on the front and rear and both observers are at the midpoint of their train. So if the speed of light is constant in vacuo how can either, or any observer for that matter, detect the explosion flashes simultaneously inside their own frame unless they were at absolute rest ? I'd like to hear your response on this point before I comment on the rest. I'm sure your response will involve a discussion about length contraction/time dilation so I'm curious how this will work. Seems to me that one half of the train should be contracted while the other half expanded for this to work. Well, sorry but this sounds ridiculous.

Excuse me for butting in like this but here is one possible soluiton.If I understand the problem we could have a situation like the following.

            o ____________m1____________0 ->v1


                  \   /         \  /
                   x1            x2
                  /  \          /  \
                     

  <-v2        o___________m2_____________o

As I have drawn the situation the explosions at x1 and x2 are simultaneous and arrive at the midpoints of each moving frame, by sheer luck, but it is consistent.
The diagram is a set of equilateral triangles here each moving frame is located such that the photons from the explosions arrive simultaneously at the midpoints and end points of each train simultaneously. However the photons do not necessarily arrive on each train at the same time. The arrive on the trains simultaneously. Well maybe with a slight discussion.

The bottom train where the triangles are true equilaterals the photons arrive at the end points and the center point simultaneously. In the other train which may be say twice as far from the explosions as the first, the photons can arrive at the midpoint before the photons arrive at the end points. However, each conclusion will be the same the photons were emitted simultaneoulsy as this is what was observed. It would be a mistake to link the two frames which are completely independent of each other to say that if one sees the explosions simultaneously the other cannot see the explosions simultaneously,

It might help to have clocks that stop when the explosions reach the trains, which would end the speculation.

As I contrived the experiment it is possible for the frames, or an infinite number of frames, to see the explosions as simultaneous. A contrived situation, but possible.

 

[ram1024]

which has a nother day or two to survive and that is just becasue ram1024 is extending a proferssional courtesy

i'm wondering how the heck he knew i was holding something back :O
trying to be unpredictable and he's reading my game

 

[geistkiesel]

Another point I am confused with is this: if any inertial frame can consider themselves to be at the center of arbitrary emission events, doesn't that equate with the emitters of the light being at rest with respect to each inertial frame? If so, how can any inertial frame detect doppler shifting of light from two continuous emission sources? That is, if there is never any relative velocity between emission sources and the detection frame, how could light be doppler shifted in different inertial frames? Or if Doppler shifting of light was allowed, surely the observer that detects the flashes as non-simultaneous can deduce that his frame was in motion relative to the light emitters and hence the actual time of occurrence of the events?

I am not sure i have you exactly as you mean, but here is a try.

I have used the dopller shift argument to explain away the claim that two frames cannot determine which is moving with respect to whom. In the standard Einstein train station moving train experiment the flashes can occur in either frame. The frame not holding the source of the emitted photons would naturally see a doppler shift.

Another way to tell how each frame is in motion with respect to the other is to look at the acceleration data of each frame. If three frames were at one time at rest wrt the earth, for instance and each acceleratss, one for 1 g for 5 minutes, another 1 g for 7 minutes and the thirid 1 g for 10 minutes and knowing the mass of each, (easy if standardized frames), relative velocity could be defined by such information.

 

[wespe]

Two trains have a relative speed. They both have burn marks on the front and rear and both observers are at the midpoint of their train. So if the speed of light is constant in vacuo how can either, or any observer for that matter, detect the explosion flashes simultaneously inside their own frame unless they were at absolute rest ? I'd like to hear your response on this point before I comment on the rest.

From that, I guess you are imagining that speed of light is constant with respect to "aether". No, speed of light is measured the same in all frames (counter intuitive, but experimental fact). Also, I guess you are imagining that the explosions occurred simultaneously according to "aether". I didn't say that. They just occur at two times, that's not given. We are investigating wheter they occurred simultaneously according to the two trains, by using the two midpoint observers. And they won't agree about simultaneity, that's the main point.

Does that clarify?

 

[geistkiesel]

A Modified ram1024 buoy? or is ot the same?

i'm wondering how the heck he knew I was holding something back :O
trying to be unpredictable and he's reading my game

I have a mofdified ram1024 buoy. It might be the same so let me know. It is a six sided cube, for three directions of motion to cover. Assume each set of parallel sides has its own photon source at the midpoint of the sources. If the buoy is moving in one direction, say along the x-axis the return reflections from the two sides is detected at the midpoint and a relative velocity wrt the light speed is detected.

The surfaces of the mirrors have photon detectors that determine the time the photons arrived and hence determine the speed and direction direction (hey that's velocity) and by applying a little braking force the x direction velocity can be minimized to what, zero, of course. (I am using a modified Einstein gedanken; The photons moving in the diretion of motion will take longer to reach its intended surface than the light directed at the surface closing in on the oncoming photon. Sounds like more of an engineering problem than physics.)The other two directions can be manipulated the same. In fact the calculations of the velocity in the three directions can be calculated more or less at the same time, ergo, the buoy can be brought to zero velocity, wrt to the speed light., fairly quickly. This would give a very accurate zero velocity - 1 part in 3x10 ^8m/sec for +- 1 meter, better if using centimeter or millilmeter, or what evere the creative genius of the current inertial frame engineers determines.

The rest of the moving stellar objects in the universe can move as they will, but one buoy can determine a zero velocity wrt c.

Is this in line with the ram1024 version? Each frame can radiate a number giving its relative absolute velocity or error correction information. Why would any SRist want to complain about at least trying something like the ram1024 buoy? Hell we've got all the money in the universe, effectively, we being the us of a.

I would only caution about trying to correct all three directions at the same time, after all Mother Nature's last act before launching her creation as a universe was to add time so everything wouldn't happen all at once.

 

[ram1024]

heh it is quite similar to the URF Space-Buoy, but that was a creation i made knowing it would fail, not according to SR precepts per se, but due to my own.

the problems that arose with it were the need to calibrate it accordingly. i had used clocks synchronized at zero-point and then moved into positions using and intricate and precise technique, but SR people refused to let that be the true deciding factor for the device.

they did allow me to synchronize using the midpoint as simultaneous light reception. what this would do would allow the device not to be able to find the Universal Reference Frame (Absolute Stationary), but instead allow the device to calibrate to one specific inertial frame, and be able to detect any deviation from this frame precisely.

in this sense we could define frames throughout the universe simply by knowing the values of deviation from our defined "earth frame". A buoy with known "Earth Frame" values could be set up in another system light years away to measure "Earth Frame" in respect to "That Other System's Frame" just by letting the buoy jet until it reaches "Earth Frame Equilibrium"

hmm didn't mean to write a novel :D but yeah, technically according to SR's constant light speed thing the device you described would have to work... but only if they allowed zero-point synchronization

 

[wespe]

Another point I am confused with is this: if any inertial frame can consider themselves to be at the center of arbitrary emission events, doesn't that equate with the emitters of the light being at rest with respect to each inertial frame? If so, how can any inertial frame detect doppler shifting of light from two continuous emission sources?

An observer can consider himself to be at rest with the emission point of a single photon, regardless of the relative speed of the photon source. Also same with successively emitted photons, but the emission point for those successive photons will be getting closer/farther as the source moves, so the final effect is doppler shift.

That is, if there is never any relative velocity between emission sources and the detection frame, how could light be doppler shifted in different inertial frames?

I'm a bit lost here. If there is no relative velocity between emitter and detector, ther is no doppler shift. Are you imagining that light itself gets modified? Detected frequency/wavelength is a relation (can't find a better word for this right now) between emitter and detector, light itself remains same.

Or if Doppler shifting of light was allowed, surely the observer that detects the flashes as non-simultaneous can deduce that his frame was in motion relative to the light emitters and hence the actual time of occurrence of the events?

If I don't misunderstand you, no, doppler shift can't be used to detect absolute motion, because it doesn't matter if the emitter or detector is "moving", only relative speed matters.

 

[Chronos]

Physics 101

 

[wespe]

heh, geist is scary. he'll be all quiet and calm for a week then BAM he'll jump in with a sledgehammer and hit you with pages worth of arguments.

I'd say more like frustrating. At some point you will wear everyone out. What you guys are doing isn't anything like physics. You are just rejecting SR because it seems to defy common sense, which we all understand (no we aren't crazy). But you can't ignore experiment results which are in accordance with SR, not the intuitive Gallilean relativity (I'm not sure Geistkiesel understands even that). Other people aren't stupid, not to mention 100 years of brain power combined. You can see I'm frustrated with you Ram and Geistkiesel too.

 

[geistkiesel]

I'd say more like frustrating. At some point you will wear everyone out. What you guys are doing isn't anything like physics. You are just rejecting SR because it seems to defy common sense, which we all understand (no we aren't crazy). But you can't ignore experiment results which are in accordance with SR, not the intuitive Gallilean relativity (I'm not sure Geistkiesel understands even that). Other people aren't stupid, not to mention 100 years of brain power combined. You can see I'm frustrated with you Ram and Geistkiesel too.

No I don't reject SR just because it defies common sense, even though it surely does that, at least you do see that. If you have been following my threads on the subject I use a hell of a lot more than "violations of common sense" if you are paying attention like you claim you are. You might not agree with me and my techniqoues and you might be frustrated, so what? Do you see that ram1024, myself, grounded and eyesaw, to name a few, even yourself once, remember wespe, are all approaching from a different point of view, but guess what there is a focus and we aren't as far apart as we were last month last week or yesterday, right? I suspect each has a secet desire fror recognition at the very least. There is a purpose, personal I mean, in ewhat anybody does, right? And for physics forums, theory development it sure isn't the money, is it? Are you getting paid? I wopuld be soely poissed if Wspe was getting some quid pro quo and I was only getting my regular monthly DSL bills. :surprise: I can assure you that my pockets are as bare as they were when I started this.

You were a lot more interesting and energetic, to yourself as I observed, even when you realized how far off the nornmal path you actually were. But wasn't it energetic, stimulating, got the old gray cells moving in ways you didn't know they could move?
:surprise:
Wespe no one is saying experimental results aren't what they are.

A stupid trout example. Let us say you have a watch that runs fast. The watch is expensive, the best in town. The only thing you use the watch for is its designed purpose: measuring the speed that trout swim in cold water. Let us say the watch has trout moving 1.2 times what was measured using ordinary watches. Since your watch was so expensive and calibrated, wrongly it seems, it was hard to reject such expensive technology. Trout around the world are now believed to swim in cold water 1.2 faster than heretofore thought since All trout swimmer measurers got a wespe watch that has the same built in error. So when a trout is found not to swim 1.2 faster than wespe's watch expects, it is probably due to using a watch other than wespe's so someone comes up with the excuse that wespe's watch which is used under water etc. is the only accurate measure, therefore the trout found out of sink, (pun intended) get explained away by some inane and inexplicable nonsnese, like dark matter, or ptolemy's circles within circles, restricted fin action, you know hre drill. But every time wespe's watch is used the trout swim at 1.2v as expected. Therefore, only use wespe's watch and all the associated techniques of using the watch will get you back on the proper physical tack if you want to measure trout swimming speed according to physical law: go wespe's watch!. After a while truth takes on a different turn that is coaxed along with each finding of a conflict. Dissidents are exiled to Theory Development forums, oh the horror, the horror...

I said the example was stupid, but the metaphorcal inanity is in synch with built in "always observed in experiental results" rhetoric.

One thing you have never done is publically or privately, made a decent and honest effort, your own standards, in taking soemone's appraoch and see if there is anything reasonable or appropriate. Check out some of Doc Al responses to my posts. Sometimes he is on, other times he is just screaming in my face and he claims it is physics I am getting. You know all about that don't ya?

I consider tom_mattson a very bright guy, but he doesn't always approach physics as I feel he should, he would agree at least partially on this (not openly, after all he is a mentor and like America's greatest thepian of all times, yes I speak of John Wayne, was fond of saying, "Don't apologize it is a sign of weakness." He might have used the word "pilgrim' in this context here I am not sure.) sometimes just like a normal person he goes screaming at someone repeating SR mantras, do you dig it? If it weren't for dissidents of fundamental concepts of science and our beloved physics all worhtwhile activity of human kind would stagnate, wouldn't it, hasn't it?

I can tell from this post it is way past my bedtime.

 

[russ_watters]

Wespe no one is saying experimental results aren't what they are.

What you and the others don't understand or simply won't accept is that what the experimental results say directly contradicts you. When this is pointed out and we ask that you give an example of one experiment that contradicts Relativity, you guys turn conspiracy theorist, claiming the results are faked, experimenters lie, and there is a vast conspiracy among scientists to hide the flaws in Relativity. This is why I (and finally, just about everyone else) have stopped playing this little game of obfuscate-the-thought-experiment with you guys. Are you dishonest? Are you blind? At this point, I don't really care.

 

[Doc Al]

No SR is the key result of simultaneity, read the history sir.

Gibberish.

BS. NASCARS are running invariant in speed in my example and you ignored that example.

Unless your NASCARS are running at the speed of light, their speeds are not invariant.

Eintein does not use any SR postulate in arriving at his conclusion.

Of course he does: the invariant speed of light.

He uses only the the staggrered arrival of theh B photon and A photon as detected by the O' observer. You have said on many occasions that this is what all agree.

That "staggered arrival" by itself means nothing. But when coupled with Einstein's postulate of the invariant speed of light, then you can conclude that simultaneity is relative.

quote Doc Al "The fact (agreed by all) the light from B hits O' before the light from A leads the O' observer to conclude the lights could not flash simultameously."

Right--assuming that the speed of light is frame invariant.

How do you know this? They must check the times they are on opposite ends of the train, but each immediately relay their findings to O' who receives the data along with the simultaneous observation of the A and B photons arriving at M simultaneously.

I know it because I know relativity. Realize that your sleight of hand of "relaying their findings" doesn't change their findings.

You are invoking SR time dilation and mass shrinking right?

(What the hell is mass shrinking?)

What else could you be invoking to make your statement that the observers at A and B will not record the same time of the emitted photons.

You are babbling again: Observers at A, B, a, and b all record the time that the photons were emitted. A and B record the same times; a and b record different times.

The photons know nothing of SR theory or even that there are two observers dutifully recording the times the photons are emitted.

The photons don't have to know SR; but if you wish to make an accurate prediction of how they behave, you'd better know SR. You don't.

the a and b observers record the same time.

On what basis do you make that wild and incorrect claim?

Remember, what you said back in the Lost simultaneoity thread. let me remind you:
quote by Doc Al
"If you understood the Eisntein simple argument you would know that nowhere does "time dilation" or " mass shrinking" enter into it"

Right! Let's be perfectly clear:

Does Einstein need to invoke "time dilation" or "length contraction" to prove that simultaneity is frame dependent in his Train Gedanken: No! All he needs to invoke is the invariant speed of light.

Does that mean that "time dilation" and "length contraction" are irrelevant to a complete analysis of the Train Gedanken? No! To go beyond Einstein's simple argument, and completely describe all events from each frame you must include the effects of time dilation, length contraction, and the relativity of simultaneity. For example: Where is observer a on the train? observer b? What times do their clocks read when they detect those photons being emitted from A and B? Where is the train when these photons are detected? All these questions are from the train frame: to get the answers, you need to understand SR.

 

[geistkiesel]

Einstein tells us that the mere staggered arrival time of the photons and that c is constant as everybody knows, is all that the passenger have that they "'must, therefore come to the conclusion" the photons were not emitted simultaneously. The same would hold for the NASCAR hypothetical.

That "staggered arrival" by itself means nothing. But when coupled with Einstein's postulate of the invariant speed of light, then you can conclude that simultaneity is relative.

AE said the staggered arrival times was everything. So you alter AE's conclusions do you? To win an argument, or to keep it going from your naive prerspective and to hell with physics. AE did not inlcude the invariant speed og light as you are trying to stuff it in some crack here in the conversation where it doesn't belong and where only a classic DOc Al smog bank is created. Your light invariant argument doesn't get off the grouind. It was redlined Doc. That kite doesn't fly.


Einstein says: "Hence, the observer will see the the beam of light emitted from B earlier than he wills see that emitted from A. Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash at B took place earlier than the lightning flash A. We thus arrive at the important result: Events which are simultaneous with reference to the embankment are not simultaneous wrt the train and vice versa."

Also if O' weren't moving O' would see the lights emitted simultaneously.
I read, motion, staggered arrival and the speed of light is c.

So what I infer from this is that the observers that see the lights arrive simultaneously at M', here frame wise no different than where O' had just measured the arrival of B, there would be no loss of simultaneity as the photons would have arrived simultaneously. All your postulates and arguments are included. I also conclude that to the O' observer the photons were not emitted simultaneously in the moving frame, but only by definition, and that for the a|b observers at the midpoint M when the photons A and B arrive simultaneously, the emitted photons were simulaneously emitted in the stationary and moving frame.

Therefore the Sr theory predicts that on the same frame there are a multitude of observers seeing the simultaneous arrival of the photons as well as a multitude seeing no simultaneity.

The observers at A and B, a and b, are also recorded the times the photons were emitted and must also conlcude the photons were emitted simultaneously. Assuming the observes a and b know they are measuring photons that are simultaneously emitted in the stationary frame, they must conclude they are measuring the same as their partner on the olther end of the frame. The a and b clocks are moving frame synchronized, therefore each clock always reads the same. Therefore the a and b clocks a must read the same as the clocks used by the observers at M viewing the arrival of the A and B photons arriving simultaneously there. and of course, O'.

Another problem you have. Assume the stationary frame emits ionly one photon instead of two. Will the photon anticipate which photons it was that had photons been emitted simultaneously from both sources?

If the B photon is exclusively emitted will it be measured the same instant of emittance as in the case the A photon were emitted also? How do the photons know they are a pair and that one must precede the other? Nonlocal entanglement?

How do you come to the conclusions you do? If the a and b observers and the a|b observers all relay their times to O' the signals will arrive simultaneously with the A photon. Hence O' will have two unambiguous data sources indicating simultaneously emitted photons. But you know different, why?

I know it because I know relativity. Realize that your sleight of hand of "relaying their findings" doesn't change their findings.

I never said it did change their findings. I was merely giving you some alternative to observations of passengers on Einstein's train that conclude the photons were emitted simultaneously in the moving frame, obviously.

This hypo of AE is no different tha the conclusion spectators at the NASCAR race I described will also conclude the NASCARS emitted form A and B emitted sinmultaneously as determined by the moving Ford Futura, the analog of O', as well as 100,000 spectators viewing the event.

(What the hell is mass shrinking?)
You are babbling again: Observers at A, B, a, and b all record the time that the photons were emitted. A and B record the same times; a and b record different times.
The photons don't have to know SR; but if you wish to make an accurate prediction of how they behave, you'd better know SR. You don't.

Prove the a and b and the a|b passengers will not measure the same as the A and B observers. "I know it because I know relativity." This is your physics, "I know", is your physics?. The forum is there for you to put your knowledge on the line and to prove what you know.

What do we do in the alternative, just start calling each other names and making the wise cracks? By the way, if you were looking for the job of smart ass, that job is already filled, and by a real professional. Need I say more?

On what basis do you make that wild and incorrect claim?

Wild guess, maybe or finally, but it turned out OK, like some of the other wild guesses that turn out ok. Incorrect though, you must show those with more than "I know".

From the reason and logic learned in the study of physics. Einstein didn't use a gamma in his gedanken, nor did he infer the existence of a gamma regarding the conclusions derivable form the gedanken, but Doc Al can hardly wait. However,I anticipate no such physics will be forthcoming from Doc Al.

Right! Let's be perfectly clear:

Does Einstein need to invoke "time dilation" or "length contraction" to prove that simultaneity is frame dependent in his Train Gedanken: No! All he needs to invoke is the invariant speed of light.

That is what I thought, there is no definitive SR postulate or imperative that proves the a and b observers did not observe the photons emitted simultaneously, and the same ogres for th a|b [passengers agt the midpoint when A and B pohoton s arrive there simultaneously.

Does that mean that "time dilation" and "length contraction" are irrelevant to a complete analysis of the Train Gedanken? No! To go beyond Einstein's simple argument, and completely describe all events from each frame you must include the effects of time dilation, length contraction, and the relativity of simultaneity.

I knew it, you flim flammed us, or are trying to.

Try looking at this again:
"Hence, the observer will see the the beam of light emitted from B earlier than he wills see that emitted from A. Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash at B took place earlier than the lightning flash A. We thus arrive at the important result: Events which are simultaneous with reference to the embankment are not simultaneous wrt the train and vice versa."

You mean that if we just use different observers than O', then you have to use time dilation and length contraction, AKA mass shrinking.? Sounds like a fast swimming trout story to me.
Bogus Doc, you can do much better. You seem to think nobody remembers what you just posted above, in this post. AE didn't need it but Doc Al needs it in order to smog up the discussion and keep some semblance of SR alive. Chill DOc. ram1024 has given everybody another couple of days, Relax, prepare yourself for the inevitable. Don't embarrass yourself.

For example: Where is observer a on the train? observer b?

a and b are at A and B when the photons were emitted into the moving frames, which is recorded by their clocks. a nad b obseved the phtons being emitted. a and b recorded the time of the emitted photons when emitted simulataneoslh at A and B.

What times do their clocks read when they detect those photons being emitted from A and B?

t' = 0. The same as the O' observer who zeroed her clock when she arrived at the midpoint just as the photons were emitted simultaneously from A and B. Long before the O' detected the staggered arrival of the B and A photons. Come on we have done this scene many times before.

Where is the train when these photons are detected?

The train? Come on Doc, please. Doc the passengers are riding on the train. a is at A, b is at B and O' is at M, when the clocks were set to zero, remember?

All these questions are from the train frame: to get the answers, you need to understand SR.

To get the answers? I do know SR. I even understand it. It's just isn't true that's all. The a and b observer record the A and B photon simultaneously when emitted at A and B, as do the a|b observers when the A and B photons arrive at M simultaneously.

You think you are going to blind side the maths ignorant geistkiesel do you? Try me Doc. I dare you to try me.

Ese el mentor!: la li'nea habe dibujado en el desierto con lamis espada. Aqui! ahora!

1. Question Doc Al: How do the a and b observers know there are two photons emitted from the stationary frame?
   
2. or said another way, how do the photons know they must change their emittance protocol because the photons are about to be emitted into the moving frame?
3. How do the photons know which one must emit first,
4. and at what what time? [*] I think you are digging yourself a perception of the observers hole instead of building a phyisics arguement.

.

 

[Doc Al]

Einstein tells us that the mere staggered arrival time of the photons and that c is constant as everybody knows, is all that the passenger have that they "'must, therefore come to the conclusion" the photons were not emitted simultaneously.

Yes, and your point is what? "c is constant" means "the speed of light is invariant".

AE said the staggered arrival times was everything. So you alter AE's conclusions do you? To win an argument, or to keep it going from your naive prerspective and to hell with physics. AE did not inlcude the invariant speed og light as you are trying to stuff it in some crack here in the conversation where it doesn't belong and where only a classic DOc Al smog bank is created. Your light invariant argument doesn't get off the grouind. It was redlined Doc. That kite doesn't fly.

It's time to up the dosage on your medication, geistkiesel. What do you think "constant speed of light" means?

The observers at A and B, a and b, are also recorded the times the photons were emitted and must also conlcude the photons were emitted simultaneously.

Wrong.

Assuming the observes a and b know they are measuring photons that are simultaneously emitted in the stationary frame, they must conclude they are measuring the same as their partner on the olther end of the frame.

Wrong. All a and b do is observe the times of emission and record it. They observe different times.

The a and b clocks are moving frame synchronized, therefore each clock always reads the same. Therefore the a and b clocks a must read the same as the clocks used by the observers at M viewing the arrival of the A and B photons arriving simultaneously there. and of course, O'.

After all these posts you still haven't the foggiest notion of what's going on. Clocks a and b are syncronized in the O' frame; so of course they read "the same time" in the O' frame. But emissions at A and B do not happen at the same time in the O' frame.

Another problem you have. Assume the stationary frame emits ionly one photon instead of two. Will the photon anticipate which photons it was that had photons been emitted simultaneously from both sources?

Huh? Totally incoherent. What are you talking about?

If the B photon is exclusively emitted will it be measured the same instant of emittance as in the case the A photon were emitted also? How do the photons know they are a pair and that one must precede the other? Nonlocal entanglement?

Huh? Totally incoherent. What are you talking about?

How do you come to the conclusions you do? If the a and b observers and the a|b observers all relay their times to O' the signals will arrive simultaneously with the A photon. Hence O' will have two unambiguous data sources indicating simultaneously emitted photons. But you know different, why?

You keep claiming that a and b measure the same time? Where do you get this? Read Einstein's train gedanken one more time.

Try looking at this again:
"Hence, the observer will see the the beam of light emitted from B earlier than he wills see that emitted from A. Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash at B took place earlier than the lightning flash A. We thus arrive at the important result: Events which are simultaneous with reference to the embankment are not simultaneous wrt the train and vice versa."

I think you are the one who should look at this again. It obviously hasn't sunk in yet.

a and b are at A and B when the photons were emitted into the moving frames, which is recorded by their clocks. a nad b obseved the phtons being emitted. a and b recorded the time of the emitted photons when emitted simulataneoslh at A and B.

a and b record the times that A and B emitted the photons. OK, so what time is that, geistkiesel? I want the actual time seen on the O' clocks in terms of L, v, and c. (Hint: look back over the many posts I've made: I spell it all out for you.) A and B only flash simultaneously in the O frame. (Or have you already forgotten the Einstein quote you just entertained us with?)

t' = 0. The same as the O' observer who zeroed her clock when she arrived at the midpoint just as the photons were emitted simultaneously from A and B. Long before the O' detected the staggered arrival of the B and A photons. Come on we have done this scene many times before.

Yes we have. And yet you still get it wrong!

Clocks at A and B time the flashes to occur at t = 0. All of the clocks in O' (including a and b) are synchronized in the O' frame. We agree that when M' passes M their two clocks both read zero. Everything else must be deduced.

1. Question Doc Al: How do the a and b observers know there are two photons emitted from the stationary frame?
   
2. or said another way, how do the photons know they must change their emittance protocol because the photons are about to be emitted into the moving frame?
3. How do the photons know which one must emit first,
4. and at what what time? [*] I think you are digging yourself a perception of the observers hole instead of building a phyisics arguement.

What are you babbling about now? What's this nonsense about photons changing their "emittance protocol"? And photons conspiring together?

Einstein's train gedanken is as simple a set up as you are going to get (but obviously not simple enough!). Two lights flashing. No conspiracy. No "emittance protocol". Just the invariant speed of light.