Twin paradox (Pete and MacM)

[2inquisitive]

by Paul T:


"How could you think that only length contraction exist but time dilation does not?"
=======================================================

Maybe MacM got that idea because that is what Special Relativity portrays
for an object moving at a velocity near 'c' in a trajectory 90 degrees
perpendicular to a Earth-based observer. Lorentz contractions occur only
along the direction of movement, while time dilation is not based on the
direction of movement, but in all directions. Can you, or any other physicist,
explain this breech of physics to me?

 

[2inquisitive]

I can post a very simple thought experiment of what I am questioning. Everyone is
aware we bounce laser light off a reflector on the moon to arrive at a very accurate
measurement of the velocity of light, the timed round trip travel of light to the moon
and back, a known distance when the laser is fired. Place the reflector on the side
of ship traveling overhead at a perpendicular trajectory to the laser. The laser is fired
to intercept the ship when the ship is exactly at a 90 degree angle perpendicular to and exactly 299,792,458 meters in distance from the laser. A stopwatch at the laser
will record a round trip of 2 seconds for the laser beam to return. What will a stopwatch on the ship record for the travel time of the beam to the ship and back to the
Earth if the ship is traveling at, say, .866c?

 

[Paul T]

2inquisitive,

by Paul T:


"How could you think that only length contraction exist but time dilation does not?"
=======================================================

Maybe MacM got that idea because that is what Special Relativity portrays
for an object moving at a velocity near 'c' in a trajectory 90 degrees
perpendicular to a Earth-based observer. Lorentz contractions occur only
along the direction of movement, while time dilation is not based on the
direction of movement, but in all directions. Can you, or any other physicist,
explain this breech of physics to me?

I don't think that the case. MacM thinks, Lorentz contraction is real and time dilation isn't. From there we should expect the following:

Say, you are in a spaceship moving at v=0.6c from earth to moon. If earth-moon distance is 1.2c second, according to earth observer you need (1.2c second)/0.6c=2 seconds to reach moon. Now, from your point of view. You see earth-moon distance as 0.8*1.2c second = 0.96c second. According to MacM's interpretaion, you still need 2 second (instead of 1.6second suggested by standard SR) to complete the trip and therefore you will find that your velocity relative to earth (or moon) is (0.96c second)/2 = 0.48c. This cannot be right (Correct only based on MacM's relativity, which is the wrong version of relativity).Based on standard SR you will still see the relative velocity as (0.96c second)/1.6 = 0.6c! There is nothing to talk about on MacM's view on this matter, seriously, because his view is WRONG.

 

[2inquisitive]

No one wants to take a stab at solving the little paradox I posted earlier? I know
what the problem is, that is precisely why I stated the paradox in the way I did.

 

[MacM]

2inquisitive,

I don't think that the case. MacM thinks, Lorentz contraction is real and time dilation isn't. From there we should expect the following:

Say, you are in a spaceship moving at v=0.6c from earth to moon. If earth-moon distance is 1.2c second, according to earth observer you need (1.2c second)/0.6c=2 seconds to reach moon. Now, from your point of view. You see earth-moon distance as 0.8*1.2c second = 0.96c second. According to MacM's interpretaion, you still need 2 second (instead of 1.6second suggested by standard SR) to complete the trip and therefore you will find that your velocity relative to earth (or moon) is (0.96c second)/2 = 0.48c. This cannot be right (Correct only based on MacM's relativity, which is the wrong version of relativity).Based on standard SR you will still see the relative velocity as (0.96c second)/1.6 = 0.6c! There is nothing to talk about on MacM's view on this matter, seriously, because his view is WRONG.

This is horseshit. MacM has never made any such gobble-de-gook comments.

Further, I have not said I believe in length contraction but not time dilation. Learn to read and learn to write. Stop misrepresenting my views.

I have said and I repeat here.

It is shown that "BOTH" length contraction and time dilation cannot be physical realities in that for them to function simultaneously causes the observed clock display to not match the actual display of the clock. Only one can be physical and the other must be perceptional. Pick one.

[post=703574]That view is confirmed Here[/post]

 

[Paul T]

Say, you are in a spaceship moving at v=0.6c from earth to moon. If earth-moon distance is 1.2c second, according to earth observer you need (1.2c second)/0.6c=2 seconds to reach moon. Now, from your point of view. You see earth-moon distance as 0.8*1.2c second = 0.96c second. According to MacM's interpretaion, you still need 2 second (instead of 1.6second suggested by standard SR) to complete the trip and therefore you will find that your velocity relative to earth (or moon) is (0.96c second)/2 = 0.48c. This cannot be right (Correct only based on MacM's relativity, which is the wrong version of relativity).Based on standard SR you will still see the relative velocity as (0.96c second)/1.6 = 0.6c! There is nothing to talk about on MacM's view on this matter, seriously, because his view is WRONG. ”

This is horseshit. MacM has never made any such gobble-de-gook comments.

You might have never said something exactly as the above. The point is, that's should be the case based on your view as quoted below:

It is shown that "BOTH" length contraction and time dilation cannot be physical realities in that for them to function simultaneously causes the observed clock display to not match the actual display of the clock. Only one can be physical and the other must be perceptional. Pick one. ” ​

Bullshit! When you are in that spaceship, you just see your own clock; start counting when you pass the earth and stop counting when you reach the moon. What is the time interval for the trip (2 seconds or 1.6 seconds)? That's all the matter. Why should you introduce new properties for the moving clock's time as a mere perception, etc...etc? You view is baseless and useless.

Stop playing with your useless words: physical realities, illusion, perception etc. Translate it into numbers, why is it so hard for you to do that?

Now, give a straight answer based on your view. In the above example:

1) What is the earth-moon distance according to the spaceship observer?
2) What is the time interval for the trip according to the spaceship observer?

Presumably, you have no problem to accept that according to the earth observer, the distance and time interval are respectively 1.2c second and 2 seconds.

 

[MacM]

You might have never said something exactly as the above.

You damn right I didn't say something exactly as the above. You made it up to support your own arguement. Which is what you typically do.

The point is, that's should be the case based on your view as quoted below:

It is shown that "BOTH" length contraction and time dilation cannot be physical realities in that for them to function simultaneously causes the observed clock display to not match the actual display of the clock. Only one can be physical and the other must be perceptional. Pick one. ” ​

Bullshit! When you are in that spaceship, you just see your own clock; start counting when you pass the earth and stop counting when you reach the moon. What is the time interval for the trip (2 seconds or 1.6 seconds)? That's all the matter.

Really?. Interesting. What the clocks actually display shouldn't be considered. HeHeHe. Idiot.

Why should you introduce new properties for the moving clock's time as a mere perception, etc...etc? You view is baseless and useless.

Stop playing with your useless words: physical realities, illusion, perception etc. Translate it into numbers, why is it so hard for you to do that?

It might be because physical reality is what the clocks actually read is the only important issue and the only issue I have argued for two years. I have never said your fairytale observation can't happen. I have said it isn't physical reality and I am right once more. Live with it.

Now, give a straight answer based on your view. In the above example:

1) What is the earth-moon distance according to the spaceship observer?
2) What is the time interval for the trip according to the spaceship observer?

Presumably, you have no problem to accept that according to the earth observer, the distance and time interval are respectively 1.2c second and 2 seconds.

I have no reason to recompute a different scenario and to argue against "Illusion". The issue "Physical Reality" has been resolved (in my favor) end of arguements.

 

[Pete]

<img src="/attachment.php?attachmentid=3397&stc=1">

<img src="/attachment.php?attachmentid=3398&stc=1">

 

[geistkiesel]

I can post a very simple thought experiment of what I am questioning. Everyone is
aware we bounce laser light off a reflector on the moon to arrive at a very accurate
measurement of the velocity of light, the timed round trip travel of light to the moon
and back, a known distance when the laser is fired. Place the reflector on the side
of ship traveling overhead at a perpendicular trajectory to the laser. The laser is fired
to intercept the ship when the ship is exactly at a 90 degree angle perpendicular to and exactly 299,792,458 meters in distance from the laser. A stopwatch at the laser
will record a round trip of 2 seconds for the laser beam to return. What will a stopwatch on the ship record for the travel time of the beam to the ship and back to the
Earth if the ship is traveling at, say, .866c?

I will try, but be aware I am biased and do not by into SR, but from the physics here is how I see it:

Physically, the motion of light reflected from the moon, or the space ship, is independent of the motion of the source, therefore moon reflector or space ship these sources of light (assuming the reflecrors are a source for the reflected photons), is unknown to the beam of light. Assuming that the space ships clocks are dilated proportionately to the ship's velocity then the roundtrip is measured with a dilated clock on the ship and would measure the value of "C" from the fundamental assumption of SR that the speed of light is always measured as C. However, the speed of the light the ship would measure C, in their frame, using a time dilated clock would produce the C, but how could the result be the same as the earth frame using an accelerated clock also measuring C?

Unless, the ship's clock isn't dilated and frame contraction is substituted for the dilated clock that isn't. But this would imose an artificial distance between ship and earth frame.

 

[Paul T]

You damn right I didn't say something exactly as the above. You made it up to support your own arguement. Which is what you typically do.

It was provided to explain to you how your view that "length contraction is real but time dilation is illusion" is self contradictory. Obviously, you missed it again as always. You just think "length contraction is real but time dilation is illusion", no matter the cost, whatever the implication. Sometimes I wonder how on earth there exist a guy like you who unable to understand even a relatively simple logic and yet you keep claiming that everything you have said are all correct. This is indeed very funny, like comedy movie, usually there is someone dumb who does or says illogical things. Yep, it is you....the joker of the month again!

Really?. Interesting. What the clocks actually display shouldn't be considered. HeHeHe. Idiot.

I reckon you never really rely on your clock. What's the heck, it doesn't measure time anyway. What the clocks actually display shouldn't be considered? Hahahahaha. What's a joker again.

It might be because physical reality is what the clocks actually read is the only important issue and the only issue I have argued for two years.

....and for many years to come until the day you die you will argue about this bullshit.

I have never said your fairytale observation can't happen. I have said it isn't physical reality and I am right once more. Live with it.

Hehehe, fairytale...where? It's just a matter of reading your own clock, while you are on earth and while you are travelling from earth to the moon. It was so damn simple, how long the trip according to you in the spaceship travelling to the moon at velocity 0.6c. Is it 2 seconds or 1.6 seconds?

I have no reason to recompute a different scenario and to argue against "Illusion". The issue "Physical Reality" has been resolved (in my favor) end of arguements.

OMG, for that simple exercise you need to do "computation"? It was as simple as you go to the market buy some stuff that cost you, say, $3 and 15 cents, you give the seller 5 bucks and you don't really need to use a laptop to verify that he gives you the correct change, do you? Oh well, may be you do need, given your difficulty to even do some very simple math.

Actually, I have predicted that you would have difficulty to answer the following two simple questions given to you earlier.

1) What is the earth-moon distance according to the spaceship observer?
2) What is the time interval for the trip according to the spaceship observer?​

So, let me help. Answer for question #1 was 0.96 light seconds and answer for question #2 was 1.6 seconds. Oops, I think I have written this answer before...and you were still unable to crack the problem? OMG, you are unbelivable. No wonder, you have spent over a decade on your "fusion reactor" and it remains as your unworkable proprietary, hehehe.

Based on your wrong understanding, you would have answered 2 seconds for question #2 and a relative velocity of (0.96 light seconds)/2 = 0.48c, which is wrong as the spaceship travels at velocity 0.6c according to both earth and spaceship observer. Even if your answer was 1.6 seconds, you are still wrong as you thought time dilation is an illusion, then why must it be used? Either ways, you are in deep shit.

 

[2inquisitive]

I will try, but be aware I am biased and do not by into SR, but from the physics here is how I see it:

Physically, the motion of light reflected from the moon, or the space ship, is independent of the motion of the source, therefore moon reflector or space ship these sources of light (assuming the reflecrors are a source for the reflected photons), is unknown to the beam of light. Assuming that the space ships clocks are dilated proportionately to the ship's velocity then the roundtrip is measured with a dilated clock on the ship and would measure the value of "C" from the fundamental assumption of SR that the speed of light is always measured as C. However, the speed of the light the ship would measure C, in their frame, using a time dilated clock would produce the C, but how could the result be the same as the earth frame using an accelerated clock also measuring C?

Unless, the ship's clock isn't dilated and frame contraction is substituted for the dilated clock that isn't. But this would imose an artificial distance between ship and earth frame.

The problem with your explaination, geistkiesel, is that to use the dilated
clock on the spaceship, you MUST also contract the length of the meter.
Time dilation and length contraction go hand in hand, not one without the other or you change VELOCITY. Special Relativity states that the distance to
the laser on EARTH is NOT contracted, it is at a 90 degree angle to the direction of motion of the spaceship. Slow the clock only and you change the
velocity of light in THAT frame.Meters and seconds are DEFINED by the velocity of light, 299,792,458 meters per second. Time dilation AND Lorentz
contractions are both shown to be false, unless the speed of light is NOT
invariant. Besides that, remember the moving clock is supposed to DISPLAY
less accumilated time (less than two seconds) on the spaceship.

 

[Pete]

Place the reflector on the side of ship traveling overhead at a perpendicular trajectory to the laser. The laser is fired to intercept the ship when the ship is exactly at a 90 degree angle perpendicular to and exactly 299,792,458 meters in distance from the laser. A stopwatch at the laser will record a round trip of 2 seconds for the laser beam to return. What will a stopwatch on the ship record for the travel time of the beam to the ship and back to the Earth if the ship is traveling at, say, .866c?

2.646 seconds.
This can be worked out without reference to any time dilation or length contraction equations.

 

[Pete]

You can easily figure it out using this diagram:
<img src="/attachment.php?attachmentid=3400&stc=1">

 

[2inquisitive]

Exactly, Pete. You have to put the Earth in motion and the spaceship in the rest frame
to increase the distance the light travels. However, I am sure you are aware that
Special Relativity CONTRACTS the legs of this angle and SLOWS the clock to still
make the speed of light invariant to the original distance, two light seconds. Thus it is
still two seconds according to SR.
Edit: Oh, and by the way, the 2.62 seconds would have been from the clock
on the SPACESHIP. Going the wrong way on that clock, huh?

 

[geistkiesel]

This has got to be one of the silliest things you have ever said. All you have done is show that SR does not adhere to what you think the rules of physical reality are or should be. But the universe is not obliged to adhere to your rules.

Simply showing that that the Rules of Reality according to SR and the Rules of Reality according to you don't agree proves nothing. The only way to prove which set of rules actually prevail is to physically do the experiment.

And to that end, the Rules of Physical Reality according to Relativity have passed every physical experiment thrown at them.

Please excuse this late post, but I have reached this part of the discussion between Pete and MacM. Whatever biases you and I may have in reading the discussion let me ask you a yes or no question that you are free to explain as you choose of course. Regarding the question of simultaneity in this thread do you agree that if the B and C frame each had an extra clock both programmed to run at the earth tick rate relative to their estimation, that a condition of simultaneity could be achieved among all observers?

Or even running the test in two separate tests, with the adjusted earth frame clock in each moving frame wouldn't the experiments be effectively equivalent, without simultaneity being an issue?


Therefore, "instantaneously" the three clocks shut down, simultaneously by effect of the monitoring clocks, or avoiding the simultaneity question the experiment can be run in two separate stages, There is no need to run the tests at the same time.

Finally, would you agree that the experiment could be simulated as I have described and structured below?


I am going to assume at this point your answers are Yes and in any event I ask:

Here we adjust the B and C clocks to run as SR predicts in the same laboratory in the A frame on terra firma? Where:

• All clocks are started instantaneously.
• all clocks are stopped simultaneiously when the A clock reaches 36000.
• B and C program their own clocks to run at a rate consistent with their respective assumed velocity;
• further, B and C both program separate clocks each to what the other moving frame clock would be viewed from their respective frames velocities;
• and finally B and C each program a clock to run at the assumed earth rate from their respective assumed velocities.

We begin the experiment and after the A clock counts 36000 and when all clocks are stopped what are the clock readings for:

• The B clocks for the
  • clock programmed assuming the B velocity = .1c._____________.
  • clock programmed assuming the C velocity = .9c (wrt A, or realtive to B and C)._________________.
  • clock programmed assuming the A velocity as B sees it______________
  .
• The C clocks for the
  • clock programmed assuming the C velocity = .9c._____________
  • clock programmed assuming the B velocity = .1c (wrt A, or realtive to B and C).____________________
  • clock programmed assuming the A velocity as C sees it)_______________

.

Geistkiesel

 

[Pete]

Firstly, I got the maths wrong.
Working through the diagram again, it seems that the time passing on the spaceship is 2seconds each way, for a total of 4 seconds.

However, I am sure you are aware that Special Relativity CONTRACTS the legs of this angle and SLOWS the clock to still make the speed of light invariant to the original distance, two light seconds.

No. The diagram is drawn in the spaceship reference frame. All times and distances are native to that frame.

Oh, and by the way, the 2.62 seconds would have been from the clock on the SPACESHIP. Going the wrong way on that clock, huh?

Not at all.
The two events (laser fired, laser received) were in the same place in Earth's frame. An Earth clock ticking at that point ticks one second during the beam travel.

In the spaceship frame, Earth clocks run slowly.
In the spaceship frame, there must be more time than one second between ticks of the Earth clock.
In the spaceship frame, there must be more time than one second between the laser fired and laser received.

 

[geistkiesel]

MacM:

We can easily clear this one up.



I don't really care about the details of how you stop the clocks. All I need is the following information:

For each clock, please provide the spacetime coordinates of the event "Clock x" stops, in one single reference frame.

I'll make it simple for you. Please fill in the gaps:

According to an observer travelling with clock A:

Clock A stops when it is at x=0, t=___________
Clock B stops when it is at x=__________, t=___________
Clock C stops when it is at x=__________, t=___________

Go for it.

James R,
I am reding this thread and I have goten this far. What i understood MacM to say, and he is certainly able to answer for himself, is that if a separate clock is installed in B and C programmed to run at the rate the observer in the particular frame sees the earth clock as running, which will be fast wrt the unadjusted frame clock, then we have a simulated earth frame clock riding along with the moving frame. This is done for both frames, therefore the moving frame clocks and the A clock should all shut down, "simultaneously".

If this isn't digestable, then run the test separately with the adjusted earth frame clock in the subject frame where the test is conducted.

 

[geistkiesel]

I think I've had enough.
Mac, you've got one more chance to show me you're not a blind dogmatist.

Pete,

Add a separate clock to the B and C frames programmed to run at what the observer in that frame calculates the earth frame clock as runninng and when the adjusted clock reaches 36000 stop the frame clock and record the number of ticks on the clock.

This is what MacM suggested as a way to extract the issue of simultaneity from the experiment without doing danage to SR theory including simultaneity.

You do agree do you not that the calculations made on the moving frames would give the same results if calculated on the A earth frame?

Geistkiesel

 

[2inquisitive]

Pete, you are one of the physicists on these forums that I believe has integrity.
Are you just showing that what I did was reverse the cards on SR?
4 Seconds? To start with, light has a speed of 299,792,458 meters per second.
How did the travel distance become 1199169832 meters? The spaceship and the
laser were separated by 299,792,458 meters when the light reflected off the prism
on the spaceship. And again, this is the clock on the spaceship, not the Earth.
In the Earth's frame of reference, it is at rest and the laser is fired straight up and
reflected straight back down. As I keep repeating, a moving inertial frame is NOT the
same as a rest frame. Your diagram is one proof, and SR mixes these frames freely.
quote:
"In the spaceship frame, Earth clocks run slowly.
In the spaceship frame, there must be more time than one second between ticks of the Earth clock.
In the spaceship frame, there must be more time than one second between the laser fired and laser received."
Yes, the spaceship clock would record MORE time than the Earth clock. Thanks, Pete.

 

[geistkiesel]

Clock "A" the master contol clock on earth.



Normally maybe. But not in this case. Simultaneity has been eliminated by the use of precalculated relavistic values to control the clocks. If the clocks do not shut down "Simultaneously" and "Instantaneously" with clock "A" then Relativity has failed.

So make up your mind. Do clocks in such a situation stop per clock "A" Simultaneously and instantly according to SRT?

Who said anything about hard? It simply is not addressing the conditions of the tests and/or data from the test. We don't need lessons in other claims of relativity but only to analyze the consequences and validity of this test.

MacM,
Iam just now reading the thread from beginning to end and have a suggestion which I have posted to Janus58 and James R regarding the "simultaneity" issue. First I repeated what you suggested and which they somehow didn't understand.

First, there is no reason to run the test with both frames includied at the same time. The B frame can be tested on Monday with a clock added that is programmed to run at the A frame rates as viewed by the obervers on the B frame when at uniform velocity. When that adjusted clock reaches 36000 both B frame clocks stop. On Friday run the C test in the same way.

I am assuming that calculations using SR theory will result in the same numbers whther genrated in the A frame or the moving frames.

Finally, I suggested that the entire experiment be simulated in the A frame laboratory with all moving frame clocks adjusted to run at the rate predicted by SR theory, including a clock predicting the A frame rate and a third clock predicting the other moving frame clock - B predicts B, A and C,
C predicts C, A and B, A just ticks.

The experiment is run by starting the experiment simultaneously and ending when the the unadjusted A framwe clock reaxches 36000..