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 Simultaneity on a ferris wheel at the train station. 
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Board Warrior

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Post Simultaneity on a ferris wheel at the train station.
Lightning strikes both ends of a train, simultaneously, passing through a train station.
A ferris wheel is turning in a plane that is at 90dg to the train & is halfway tween the strikes.
By symmetry, everyone on the ferris wheel will see simultaneous lightning flashes.

On The Electrodynamics Of Moving Bodies, by A Einstein (1905)
Section 2 -- On the Relativity of Lengths and Times.

Alby says (or at least the English translator says)......
...... Observers moving with the moving rod would thus find that the two clocks were not synchronous, while observers in the stationary system would declare the clocks to be synchronous. So we see that we cannot attach any absolute signification to the concept of simultaneity, but that two events which, viewed from a system of co-ordinates, are simultaneous, can no longer be looked upon as simultaneous events when envisaged from a system which is in motion relatively to that system....

But, in our ferris wheel & train & twin lightning thought experiment, everyone on the ferris wheel is sitting in a system which is in motion relatively to everyone else's system, yet they must all see simultaneous flashes.
The seats on the ferris wheel are single seats (not doubles), such that everyone is sitting in the same plane.

Hencely, Einstein's wordage is wrong.

However, it is difficult to tell whether the wordage is wrong, because it is incomprehensible.
...... would thus find ......
...... would declare the clocks ......
...... we see that ......
...... can no longer be looked upon as ......
...... when envisaged from ......


There are 4 possible types of observation, & Alby should make it clear which applies (in the above stupidly worded cases).
1. The flashes are observed to be simultaneous (with the eyes). There are then two possibilities that interest us.
1(a). The observer has information allowing him-her to determine (calculate) that the strikes are indeed simultaneous.
1(b). The observer has information that allows him-her to determine that the strikes are non-simultaneous (despite the flashes being simultaneous).

2. The flashes are observed to be non-simultaneous (with the eyes). There are then two possibilities that interest us.
2(a). The observer has information that allows him-her to determine (calculate) that the strikes are indeed non-simultaneous.
2(b). The observer has information allowing him-her to determine that the strikes are simultaneous (despite the flashes being non-simultaneous).

The information needed might include perhaps chalk-marks marking the location of the strikes & the midline, & any needed measurements of distances & angles. Although i realise that the whole thing is an impossible thought experiment, but nonetheless Alby should make it clear what is seen & what is determined (rather than his stupid -- find, declare, see that, looked upon, envisaged).
Mrs Alby wrote his equations, its a pity she didn't write his words.


Last edited by McMac on Sun Mar 19, 2017 8:45 am, edited 2 times in total.



Sun Mar 19, 2017 8:32 am
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Board Warrior

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Post Re: Simultaneity on a ferris wheel at the train station.
Paul Marmet – Einstein’s Theory of Relativity versus Classical Mechanics.
Ch9 – Simultaneity and Absolute Velocity of Light.
9.1 – Simultaneity versus Identical Clock Displays. Marmet says --

....... The problem of simultaneity has been much studied in relativity. According to Einstein,

simultaneous events in one frame cannot be simultaneous in another.

This is known as Einstein’s principle of relativity of simultaneity. When two events take place at the same time, we say that they are simultaneous. We know that Einstein always considered that time is what clocks show. Therefore when he writes that two events are simultaneous in two different frames, he means that they occur at the moment when the clocks of observers in both frames show the same display. Since we understand that time does not flow more slowly because clocks run more slowly, Einstein’s statement brings much confusion.

Instead of saying that two events simultaneous in one frame are not simultaneous in another, he should have said that

there is no identity of clock displays between clocks in different frames.

Two clocks moving independently at different velocities do not maintain identical clock displays after a time interval. This means that even if both observers see the events at the same absolute time they will record different clock displays. Einstein’s relativity of simultaneity becomes understandable only if he means that the clocks can show different displays at one given time.......


Sun Mar 19, 2017 8:40 am
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Consumed by Physics

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Post Re: Simultaneity on a ferris wheel at the train station.
How true, McMac! One clock showing two faces i.e. two readings at one time...
McMac wrote:
Paul Marmet – Einstein’s Theory of Relativity versus Classical Mechanics.
Ch9 – Simultaneity and Absolute Velocity of Light.
9.1 – Simultaneity versus Identical Clock Displays. Marmet says --

....... The problem of simultaneity has been much studied in relativity. According to Einstein,

simultaneous events in one frame cannot be simultaneous in another.

This is known as Einstein’s principle of relativity of simultaneity. When two events take place at the same time, we say that they are simultaneous. We know that Einstein always considered that time is what clocks show. Therefore when he writes that two events are simultaneous in two different frames, he means that they occur at the moment when the clocks of observers in both frames show the same display. Since we understand that time does not flow more slowly because clocks run more slowly, Einstein’s statement brings much confusion.

Instead of saying that two events simultaneous in one frame are not simultaneous in another, he should have said that

there is no identity of clock displays between clocks in different frames.

Two clocks moving independently at different velocities do not maintain identical clock displays after a time interval. This means that even if both observers see the events at the same absolute time they will record different clock displays. Einstein’s relativity of simultaneity becomes understandable only if he means that the clocks can show different displays at one given time.......
...is the correct interpretation of OEMBS (Einstein's On the Electrodynamics of Moving BodieS), rather like the two faces that RTD123 shows when he is challenged about defending SR: i.e. the cool mathematician using his logic to prove the physically impossible contrasting with his uncontrolled rage ( :? :evil: ) when antirelativists point out the physical incompatibilities with the unarguable maths.

The real pity is that it has taken a century to challenge Einstein effectively! :(

The problem with Marmot though is that he has not attacked Einstein on ALL his presumptions, since this means going back and attacking the Three Stooges' teachings i.e. those of Moe Fitzgerald, Larry Lorentz & Curly Nyuk Nyuk Nyuk Poincare.

Yours faithfully
OZLOFT


Mon Mar 20, 2017 12:59 am
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Board Warrior

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Post Re: Simultaneity on a ferris wheel at the train station.
OZLOFT wrote:
How true, McMac! One clock showing two faces i.e. two readings at one time[/i]
...is the correct interpretation of OEMBS (Einstein's On the Electrodynamics of Moving BodieS), rather like the two faces that RTD123 shows when he is challenged about defending SR: i.e. the cool mathematician using his logic to prove the physically impossible contrasting with his uncontrolled rage ( :? :evil: ) when antirelativists point out the physical incompatibilities with the unarguable maths. The real pity is that it has taken a century to challenge Einstein effectively! :( The problem with Marmot though is that he has not attacked Einstein on ALL his presumptions, since this means going back and attacking the Three Stooges' teachings i.e. those of Moe Fitzgerald, Larry Lorentz & Curly Nyuk Nyuk Nyuk Poincare.Yours faithfully OZLOFT
I am fairly certain that Marmet is anti-relativity in every way. Even after retirement he kept his office but in the end he was considered such a distraction to students (sheeple) that he was sent packing. However i will need to re-read his stuff to see what his attitude is to contraction & dilation.

There are no real physical incompatibilities with the unarguable maths & no real presumptions -- because GR & SR are just math models with zero reality. However, that Einsteinians ever thought that Einstein's contraction & dilation & mass-energy equivalence were real (not just math models), & today continue to think these are real, is not my concern here in this thread.

Likewise my attack here on the wording of Einstein's simultaneity is not in any way an attack on whether simultaneity is a real effect or a real problem, it is simply an attack on Einstein's wording within his model or models -- his wording doesn't even accord with his own world & intent & model etc. I am happy to find a wording that fits. The utter stupidity of what it fits is not my concern today in this-here thread, i can deal with all of that (again) in some other thread tomorrow.

But anyhow Einsteinians must now find some other wording for their beautiful & warm & cuddly simultaneity law or principle or postulate or hypothesis or supposition or presumption or whatever.
Do u or anybody else here know of any other forms of wording of any such simultaneity commandment, that has ever been uttered by an Einsteinian anywhere at any time for any reason ?????????????????????

Or, do u or anybody else here have some ideas of a better wording (albeit within the krappy model).


Mon Mar 20, 2017 1:43 am
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