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Tags Allais Effect , Dark Flow , relativity , Theory of Relativity

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Old 4th November 2019, 08:38 PM   #1321
Robin
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Originally Posted by SDG View Post
CM is proper time interval for 'Louis' and it is supposed to be 2s according to SR - time dilation.
It is also 2s for Dewey and Huey because they are on the platform as well and they form one grid of inertial observers.
Imagine the world lines in P and A. Check the figure 1.6; A - world line going down 2s to 'the past'. It is going to have the same 'now' moment with P and C.

Now if we would draw a line - light beam 'photon world line' - from C to A that is emitted at t=0s, at the same time as the light emitted from P; that's the problem.
CM is 2s and MA is 1cs. That's the contradiction.
And this is just gibberish.
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Old 4th November 2019, 08:41 PM   #1322
Reality Check
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Thumbs down An ignorant "That's the contradiction" delusion.

Originally Posted by SDG View Post
...CM is 2s and MA is 1cs. That's the contradiction.
5 November 2019 SDG: An ignorant "That's the contradiction" delusion.

"Now if you look here:" is irrelevant figures from what looks like a SR textbook. That will state that there is no contradiction - just the laws of physics. There are no contradictions in SR. One of the beautiful aspects of SR is its self-consistency.

SDG uses them to make up yet another scenario and makes up delusions or just ignorant word salad about that scenerio.

CM is the proper time for a set of observers along the CM world line. MA might be the proper time for a different set of observers along a different world line if SDG's incoherent imagination is what I think it is.
No one with any knowledge of SR expects them to be the same. The only way that they would be the same is if the 2 sets of observers were the on the same world line looking at the same clock. That is the definition of proper time !

Last edited by Reality Check; 4th November 2019 at 08:49 PM.
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Old 4th November 2019, 08:46 PM   #1323
Reality Check
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30 posts of ignorance, fantasies and a few lies from SDG, 30 August to 21 October 2019 (and growing!)

21 October 2019 SDG: We still complain about weeks of persistent ignorance of basic SR (Lorentz transformation and proper time).
22 October 2019 SDG: An abysmally ignorant "Newtonian relativity" question.
22 October 2019 SDG: Stupidity of a diagram showing he knew what time dilation was before he asked about it !
22 October 2019 SDG: "both blue arrows are stationary in the platform frame" gibberish
5 November 2019 SDG: An ignorant "That's the contradiction" delusion.
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Old 4th November 2019, 09:21 PM   #1324
SDG
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Originally Posted by Robin View Post
Why exactly?



The two cases are not even remotely equivalent.
Let us put x=0 and y=0 to point M for simplicity.
P observer, Huey, is at x=-sqrt(3)cs in this image then. The world line goes straight up through P.
The x, y axes are not changing for any of platform observers in the platform frame. They are static.
Observer at P is not where you marked it. The world lines for all platform observers go straight up.
Check the figure 1.6.

The world line for the train observer is under the angle. Barred O observer is your Donald.
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Old 4th November 2019, 09:25 PM   #1325
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Originally Posted by Robin View Post
And this is just gibberish.
Well, this is SR gibberish.
Just look closely at the space-time diagram. Tell me what you see.
Is CM proper time interval along the world line 2s or not?
Is MA 1cs or not?
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Old 4th November 2019, 09:39 PM   #1326
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Originally Posted by SDG View Post
CM is proper time interval for 'Louis' and it is supposed to be 2s according to SR - time dilation.
Louis neither sees any light leave, nor any light arrive, so what is this supposed to be the proper time for?
Quote:
Now if we would draw a line - light beam 'photon world line' - from C to A that is emitted at t=0s, at the same time as the light emitted from P; that's the problem.
You are confusing your diagrams. On the space-time diagram the time for C is before zero, so you can't emit a photon from C at t=0.
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Old 4th November 2019, 10:01 PM   #1327
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Originally Posted by SDG View Post
Well, this is SR gibberish.
Just look closely at the space-time diagram. Tell me what you see.
Is CM proper time interval along the world line 2s or not?
Is MA 1cs or not?
SDG
The proper time of CM is 2s.

The space-time interval of MA is 1s.

OK, what of it?
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Old 4th November 2019, 10:09 PM   #1328
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Originally Posted by SDG View Post
Let us put x=0 and y=0 to point M for simplicity.
That is hardly simple if it is inconsistent with your original diagram.

Let's put P={0,0,0,0} and P'={0,0,0,0}
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Old 4th November 2019, 10:25 PM   #1329
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Originally Posted by SDG View Post
Now if we would draw a line - light beam 'photon world line' - from C to A that is emitted at t=0s, at the same time as the light emitted from P; that's the problem.
If we normalise P to (0,0,0,0) then it can make sense for your light emitted from C at t=0.
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Old 4th November 2019, 10:30 PM   #1330
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M, C, P and A as shown on the spacetime diagram are four-vectors, right?

Proper time for CA is square root of 3. Are we still on the same page?

In other words if a light beam is emitted from the event C on the space-time diagram then it can't arrive at the event A on the space-time diagram.

(You need to distinguish between the positional vectors on your first diagram and the four-vectors on the spacetime diagram.
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Last edited by Robin; 4th November 2019 at 10:36 PM.
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Old 5th November 2019, 03:31 AM   #1331
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Originally Posted by Robin View Post
If we normalise P to (0,0,0,0) then it can make sense for your light emitted from C at t=0.
Agreed, M with x=0, y=0 was to show you that P is not correctly placed on your image.
We can move on.
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Old 5th November 2019, 03:48 AM   #1332
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Originally Posted by Robin View Post
M, C, P and A as shown on the spacetime diagram are four-vectors, right?

Proper time for CA is square root of 3. Are we still on the same page?

In other words if a light beam is emitted from the event C on the space-time diagram then it can't arrive at the event A on the space-time diagram.

(You need to distinguish between the positional vectors on your first diagram and the four-vectors on the spacetime diagram.
Why CA is not 0 for the light like 'world line'?
If we draw a line from C under 45 degree (light beam) angle towards A, the 0 photon world line, where it is going to cross MA line?
(I cannot make the drawing at the moment.)
M and that crossing point are suppose to have 2cs distance because CM is 2s and we will get that 0 proper time on the photon world line. Do you agree?
But it is going to be shorter than MA and MA is 1cs.
How is this supposed to work out for the SR?
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Old 5th November 2019, 05:21 AM   #1333
Robin
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Originally Posted by SDG View Post
Why CA is not 0 for the light like 'world line'?

If we draw a line from C under 45 degree (light beam) angle towards A, the 0 photon world line, where it is going to cross MA line?

2 cs from M
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Old 5th November 2019, 07:02 AM   #1334
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I will make the positional vectors lower case for clarity, ie p, c, a etc.

And events as upper case.

So if P is (0,0,0,0) then
M=(2,1.732,0,0)
C=(0,1.732,0,0)
A=(2,1.732,1,0)
and the intervar CA=(2,0,1,0)

Spacetime interval = -(t^2)+x^2+y^2+z^2 = -4+0+1+0 = -3

So CA isn't lightlike.

But if a light was switched on at c at t=0 then after 2 seconds it would reach y=2.

So it would reach (2,1.732,2,0), call this K

So CK=(2,0,2,0)
Spacetime interval = -(t^2)+x^2+y^2+z^2 = -4+0+4+0 = 0

to confirm it is lightlike.

And MK=(0,0,2,0)

Spacetime interval = -(t^2)+x^2+y^2+z^2 = 0+0+4+0 = 4

which matches the timelike interval of CM which is -4.

I think that is right, but I may well find myself revising this tomorrow.
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Last edited by Robin; 5th November 2019 at 07:03 AM.
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Old 5th November 2019, 07:03 AM   #1335
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Originally Posted by Robin View Post
2 cs from M
Correct and here is the space-time diagram:



This is the train figure:



So MN is 2cs and MA is 1cs at the same time.
There is no length contraction along the y axis direction apparently in SR.
Y axis units of measure are broken.
The SR cannot reconcile simple time dilation definition.
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Old 5th November 2019, 07:42 AM   #1336
Robin
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Originally Posted by SDG View Post
So MN is 2cs and MA is 1cs at the same time
They are two completly different intervals, so why shouldn't the have different time intervals?
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Old 5th November 2019, 08:21 AM   #1337
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Originally Posted by Robin View Post
They are two completly different intervals, so why shouldn't the have different time intervals?
Robin,
1cs in the y axis direction in the platform frame is supposed to be equal 1cs in the y axis direction in the train frame. That's from the proof.
The measurement of proper time intervals is done through the y axis.
The invariance of space-time intervals is broken if platform 1cs is not equal to train 1cs in the y direction.
That's the problem for the SR.
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Old 5th November 2019, 08:31 AM   #1338
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Originally Posted by Robin View Post
They are two completly different intervals, so why shouldn't the have different time intervals?
Look at it this way.
If PA is 2cs then MA has to be 1cs in the platform frame.
Concurrently, MN is 2cs in the platform frame, correct?
This comparison is within the same reference frame.
These are two rods in the same frame.
How is this not a contradiction?
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Old 5th November 2019, 12:53 PM   #1339
Robin
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Originally Posted by SDG View Post
Look at it this way.

If PA is 2cs then MA has to be 1cs in the platform frame.

Concurrently, MN is 2cs in the platform frame, correct?

This comparison is within the same reference frame.

These are two rods in the same frame.

How is this not a contradiction?

SDG
They are two different light beams ...

starting at different places and ...

aimed in different directions ...

and.you say that SR is broken if they don't end up in the same place after two seconds?

No.
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Old 5th November 2019, 02:26 PM   #1340
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Originally Posted by Robin View Post
They are two different light beams ...

starting at different places and ...

aimed in different directions ...

and.you say that SR is broken if they don't end up in the same place after two seconds?

No.
Which rod is the correct time measuring stick for the platform then?
Is is MA or MN?
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Old 5th November 2019, 02:42 PM   #1341
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Originally Posted by Robin View Post
They are two different light beams ...

starting at different places and ...

aimed in different directions ...

and.you say that SR is broken if they don't end up in the same place after two seconds?

No.

Of course, if two different light beams both arrived at the same place at the same time in one inertial reference frame, and didn't in another, that would be a contradiction. No such thing has been shown in this case, though.
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Old 5th November 2019, 03:27 PM   #1342
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Originally Posted by SDG View Post
Which rod is the correct time measuring stick for the platform then?
Is is MA or MN?
SDG
That question doesn't even make sense. You have different measuring rods to measure different things.

Neither is "correct" or "incorrect". It entirely depends on what you are measuring.

The two light beams start at different places. They end at different places.

The rod was placed in the proof in order to make a certain point in a proof. Nothing in the proof says that this rod must be the same length for every single other interval.

You are clutching at straws.

Earlier you were saying that SR was broken because that distance was 1 cs and that it should be 2cs.

Then I point out that the distance in question is 2cs and immediately you change your claim to say that SR is broken because that interval is 2 cs and it should be 1 cs.
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Old 5th November 2019, 03:56 PM   #1343
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Here is the case at t=2


The y co-ordinate for the end of the light beam in the spacetime diagram is just the y co-ordinate for where the light beams end, and they end in different places, so of course it is going to be different.
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Old 6th November 2019, 04:50 AM   #1344
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Originally Posted by Robin View Post
That question doesn't even make sense. You have different measuring rods to measure different things.

Neither is "correct" or "incorrect". It entirely depends on what you are measuring.

The two light beams start at different places. They end at different places.

The rod was placed in the proof in order to make a certain point in a proof. Nothing in the proof says that this rod must be the same length for every single other interval.

You are clutching at straws.

Earlier you were saying that SR was broken because that distance was 1 cs and that it should be 2cs.

Then I point out that the distance in question is 2cs and immediately you change your claim to say that SR is broken because that interval is 2 cs and it should be 1 cs.
Robin,
your numbers are not consistent:

Originally Posted by Robin View Post
I will make the positional vectors lower case for clarity, ie p, c, a etc.

And events as upper case.

So if P is (0,0,0,0) then
M=(2,1.732,0,0)
C=(0,1.732,0,0)
A=(2,1.732,1,0)
and the intervar CA=(2,0,1,0)

Spacetime interval = -(t^2)+x^2+y^2+z^2 = -4+0+1+0 = -3

So CA isn't lightlike.

But if a light was switched on at c at t=0 then after 2 seconds it would reach y=2.

So it would reach (2,1.732,2,0), call this K

So CK=(2,0,2,0)
Spacetime interval = -(t^2)+x^2+y^2+z^2 = -4+0+4+0 = 0

to confirm it is lightlike.

And MK=(0,0,2,0)

Spacetime interval = -(t^2)+x^2+y^2+z^2 = 0+0+4+0 = 4

which matches the timelike interval of CM which is -4.

I think that is right, but I may well find myself revising this tomorrow.

If A=(2,1.732,1,0) then K or N on my space-time diagram (2,1.732,<1,0) based on the space time diagram units of measure.

We started with y=1cs for A. That cannot change.
This y=1cs for A leads to t=2s for K/N.
If you are going to question 1cs in y direction then you are questioning 2s at the same time and that breaks your numbers even more.
Therefore your numbers do not add up.
SDG

Last edited by SDG; 6th November 2019 at 05:04 AM.
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Old 6th November 2019, 04:56 AM   #1345
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Originally Posted by Robin View Post
Here is the case at t=2


The y co-ordinate for the end of the light beam in the spacetime diagram is just the y co-ordinate for where the light beams end, and they end in different places, so of course it is going to be different.
Yes, correct, but do not stop and welcome on board
At this 2s of platform time only 1s elapsed in the train frame.
... and in 1s of train time the light crossed 2cs across the train car.

This is what I was pointing out and questioning pages ago.
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Old 6th November 2019, 05:21 AM   #1346
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Originally Posted by SDG View Post
At this 2s of platform time only 1s elapsed in the train frame.
Because it is an interval that can be measured on a stationary clock on the train and therefore dilates to the other frame, just as predicted
Quote:
... and in 1s of train time the light crossed 2cs across the train car.
It takes two seconds for it to cross the 2cs. I have no idea why you think it only takes 1 second.

So still no contradictions.
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Old 6th November 2019, 05:36 AM   #1347
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Originally Posted by SDG View Post
Robin,
your numbers are not consistent
Not consistent with your numbers you mean.

I showed all my calculations. Show me which is wrong and show me your alternative calculations you used to arrive at that peculiar figure for the y component of N.
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Old 6th November 2019, 06:09 AM   #1348
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A fundamental issue in this thread is the failure of some parties to understand the lack of an absolute frame of reference.

There is NO absolute frame of reference.

Allow me to use a biology example. Think of all observers as newborn babies. The speed, velocity, and even original position of the observers can be seen as analogous to the DNA, nutrition, exercise levels, and epigenetic expression of the babies.

In an absolute frame of reference every baby would turn out exactly the same. In the real world however we get massive differences between humans. For example:

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Old 6th November 2019, 04:07 PM   #1349
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Spacetime diagram drawn to a better scale:
So to be clear (from platform frame)

P : light beam is turned on angled 30 degrees to train side P=(0,0,0,0) P'=(0,0,0,0)
A : light beam from P arrives at half-way point on train (y= 1 cs) A=(2,1.732,1,0) A'=(1,0,1,0)
C : light beam is turned on at x=sqrt(3), y=0 perpendicular to side of train C=(0,1.732,0,0) C'=(-3,3.464,0,0)
N : light beam from C arrives at other side of the train (y=2cs) N=(2,1.732,2,0) N'=(1,0,2,0)
M : The platform clock at x=sqrt(3), y=0 reaches 2 seconds M=(2,1.732,0,0) M'=(1,0,0,0)




Rotated around to make perspective clearer (and hidden to avoid annoyance)


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Old 6th November 2019, 06:53 PM   #1350
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And same thing in train frame (dashed axes shown in green for clarity)




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Old 6th November 2019, 10:59 PM   #1351
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So un the platform, frame at t=0, the light beams at P and C are turned on

In the train frame, at t=0, P is turned on, but the beam CN has already been travelling for 3 seconds.

In the platform frame at t=1 both beams have only traversed half of their journey.

In the train frame at t=1, PA reaches A and CN completes the final second of its four second journey.

On the platform at t=2, PA reaches A and CN reaches N.

On the train both beams have travelled further.

In each second each beam travels exactly 1 c's.

For PA, delta x is zero in the train frame but not in the platform frame, so that duration dilates from the train to the platform train 1 to 2 seconds..

For CN delta x is zero in the platform frame but not in the train frame, so its duration dilates from the platform frame so the train frame, 2 to 4 seconds.

All beautifully consistent.
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Old 6th November 2019, 11:06 PM   #1352
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Originally Posted by SDG View Post

... and in 1s of train time the light crossed 2cs across the train car.
So, as above, in train time at t=0, CN has already been travelling for 3 seconds and only has 1 cs if it's journey left to complete.
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Old 8th November 2019, 06:40 AM   #1353
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Originally Posted by Robin View Post
So un the platform, frame at t=0, the light beams at P and C are turned on

In the train frame, at t=0, P is turned on, but the beam CN has already been travelling for 3 seconds.

In the platform frame at t=1 both beams have only traversed half of their journey.

In the train frame at t=1, PA reaches A and CN completes the final second of its four second journey.

On the platform at t=2, PA reaches A and CN reaches N.

On the train both beams have travelled further.

In each second each beam travels exactly 1 c's.

For PA, delta x is zero in the train frame but not in the platform frame, so that duration dilates from the train to the platform train 1 to 2 seconds..

For CN delta x is zero in the platform frame but not in the train frame, so its duration dilates from the platform frame so the train frame, 2 to 4 seconds.

All beautifully consistent.
Originally Posted by Robin View Post
So, as above, in train time at t=0, CN has already been travelling for 3 seconds and only has 1 cs if it's journey left to complete.


Robin,
all beautifully consistent.
What happens to the bold part when Louis gets distracted by a beautiful young 'duckling' and does not turn the light on at C at t=0?
The photons that have been traveling already for 3 seconds disappear?
Well, let us have 'relativity' over dead body of 'causality'.
SDG

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Old 8th November 2019, 12:23 PM   #1354
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Originally Posted by SDG View Post
Robin,
all beautifully consistent.
What happens to the bold part when Louis gets distracted by a beautiful young 'duckling' and does not turn the light on at C at t=0?
SDG
Look at both diagrams and mark off three quarters of CN.

The beautiful young duckling would have to travel back in time 1.5 seconds of platform time for that to be a problem.
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Old 8th November 2019, 02:10 PM   #1355
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Originally Posted by SDG View Post
Robin,
all beautifully consistent.
What happens to the bold part when Louis gets distracted by a beautiful young 'duckling' and does not turn the light on at C at t=0?
The photons that have been traveling already for 3 seconds disappear?
Well, let us have 'relativity' over dead body of 'causality'.
SDG
Ah, admitting you have lost. OK, then.

Hans
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Old 8th November 2019, 11:40 PM   #1356
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Here it is with the x' axis added

The little circle is where the CM line crosses the x' axis. Here is where Louis is when he is adjacent to the train clock that reads 0 seconds. His clock reads t=1.5. If he is distracted here it makes no difference, he switched on the light 1.5 seconds ago.
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Old 10th November 2019, 07:12 AM   #1357
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I havenít been keeping up with the thread the last few days. Has Bjarne come up with an equation that agrees with his theory yet, or is he still ignoring that elephant in the room?
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Old 10th November 2019, 01:05 PM   #1358
SDG
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Originally Posted by MRC_Hans View Post
Ah, admitting you have lost. OK, then.

Hans
Hans,
my friend, you know you are my friend.
Wait for it ....







No!

To take relativity over causality would be denying F=ma. That's not going to happen.
Having said that, Robin just purely formulated his response.
Going back in time is not possible, it is just a dream.


Originally Posted by Robin View Post
Here it is with the x' axis added

The little circle is where the CM line crosses the x' axis. Here is where Louis is when he is adjacent to the train clock that reads 0 seconds. His clock reads t=1.5. If he is distracted here it makes no difference, he switched on the light 1.5 seconds ago.
Robin,
what's the CA space time interval?

Quote:
...
A=(2,1.732,1,0)
...
C=(0,1.732,0,0)
...

Going by your numbers:
CA = (2,0,1,0)
CA = -3

How did you get 2s for CA time interval????!!!!?????!!!!!
Are you saying that the light travels 2s between CA?
Just remember CA is 1cs in the y direction.
SDG
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Old 10th November 2019, 09:17 PM   #1359
Robin
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Originally Posted by SDG View Post
To take relativity over causality would be denying F=ma. That's not going to happen.
Having said that, Robin just purely formulated his response.
Going back in time is not possible, it is just a dream.
Exactly, so there is no causality problem.

Quote:
what's the CA space time interval?
-3, as I have said.
Quote:
Going by your numbers:
CA = (2,0,1,0)
CA = -3

How did you get 2s for CA time interval????!!!!?????!!!!!
Do you mean time interval, or spacetime interval? You need to be specific. The delta-t between the event C and the event A is 2. The space-time interval is -3. Here is your question I was responding to:
Originally Posted by SDG
Why CA is not 0 for the light like 'world line'?
Here is what I said about CA (with the relevant part highlighted):
Originally Posted by Robin
So if P is (0,0,0,0) then
M=(2,1.732,0,0)
C=(0,1.732,0,0)
A=(2,1.732,1,0)
and the interval CA=(2,0,1,0)

Spacetime interval = -(t^2)+x^2+y^2+z^2 = -4+0+1+0 = -3

So CA isn't lightlike.
That was the entire point - a light beam from the event C will never reach event A because the interval is not lightlike.

To put is another way, if something was travelling from event C to event A it would not be travelling at the speed of light.

There is a difference between delta-t and the spacetime interval.
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"

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Old 10th November 2019, 09:35 PM   #1360
Robin
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SDG,

Let's go through the calculation slowly and tell me which part you don't follow. In all cases C and A are events:

C=(0,1.732,0,0)

Do you agree?

A=(2,1.732,1,0)

Do you agree?

and the interval CA=(2,0,1,0)

Do you agree?

Spacetime interval = -(t^2)+x^2+y^2+z^2 = -4+0+1+0 = -3

Do you agree?

The duration (ie, delta t) for CA is 2 seconds.

I am not sure which part you don't follow.
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