Why are the effects of Time Dilation permanent but Length Contraction is Not?

In summary, the twin paradox in special relativity suggests that the traveling twin will experience a slower passage of time and therefore return younger than the Earth-bound twin. This effect is permanent due to time dilation. While the traveling twin's time is affected, there is no permanent adjustment to their length due to length contraction. This is because time and distance are different dimensions and work differently. Therefore, one Lorentz transformed aspect remains while the other vanishes upon the traveling twin's return. Additionally, age is the sum of moment to moment passage of time, and there is no convenient measure for moment to moment passage of distance. This is why the traveling twin will measure less distance compared to the Earth-bound twin. However, in their own frames,
  • #1
dfaullin
11
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This question is in regard to special relativity.

From my rudimentary understanding, concerning the twin paradox, if one twin leaves traveling near the speed of light and returns, he will find himself younger than his twin who stayed behind. Hence, the effect of time dilation is permanent.

However, I have never read anywhere that the traveling twin's length will also be permanently adjusted due to length contraction.

How is it that one Lorentz transformed aspect remains while the other one vanishes upon the traveling twin's return?

I apologize if this question has been asked before. If so, and you know where to find the responses, please point me in the right direction.

Thank you!

~Dylan
 
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  • #2
Time and distance aren't the same type of dimensions and they work differently. You can walk down the street and come back to where you started, but you can't move forward in time, then go back to the time you started at. So time dilation's effects are cumulative.
 
  • #3
dfaullin said:
This question is in regard to special relativity.

From my rudimentary understanding, concerning the twin paradox, if one twin leaves traveling near the speed of light and returns, he will find himself younger than his twin who stayed behind. Hence, the effect of time dilation is permanent.

However, I have never read anywhere that the traveling twin's length will also be permanently adjusted due to length contraction.

How is it that one Lorentz transformed aspect remains while the other one vanishes upon the traveling twin's return?

I apologize if this question has been asked before. If so, and you know where to find the responses, please point me in the right direction.

Thank you!

~Dylan

Welcome to Physicsforums.

This question has been asked, but it is a good question. I don't know of an FAQ to point you to, but I am happy to answer this.

Note that accumulated time for one twin is less, but that once the twins are together, the rate of their clocks is immediately the same. Similarly, the twins height is immediately the same when they re-unite. Age is the sum of moment to moment 'passage of time'. What would be needed for distance would be a measure of moment to moment 'passage of space'. There is nothing as convenient as a clock to measure this. However, if the non-inertial twin measured the integrated distance traveled by the inertial twin, and vice versa, the non-inertial twin would conclude the inertial twin had traveled less distance (compared to what the inertial twin measures for the non-inertial twin). In this sense, there is an analogous 'permanent' length contraction effect for the twin scenario.
 
  • #4
Ah, very interesting. The traveling twin will have measured a smaller distance relative to the Earth-bound twin's measurement. That helps me feel better about it.

Because of this, will they both measure the same velocity for the traveling twin (since v=d/t)? In other words, does the smaller distance measured by the traveling twin occur in the same proportion as the smaller time measured by the traveling twin?

Also, thinking of time as accumulating (whereas length does not) helps me visualize the situation better too, so thank you for the prompt replies on the matter. I've been racking my brain on day on this stuff and it feels good to finally feel like I've accomplished something (a better understanding).

One last question: While the amount of time that passes for the traveling twin will be smaller than what is measured by the Earth-bound twin, each twin in his/her own frame does not feel time pass any differently. I guess I'm having trouble understanding how the clocks will show different times whereas the twins feel time pass at the same, normal rate in their own frames.
 
  • #5
dfaullin said:
Because of this, will they both measure the same velocity for the traveling twin (since v=d/t)? In other words, does the smaller distance measured by the traveling twin occur in the same proportion as the smaller time measured by the traveling twin?
Yes.
dfaullin said:
One last question: While the amount of time that passes for the traveling twin will be smaller than what is measured by the Earth-bound twin, each twin in his/her own frame does not feel time pass any differently. I guess I'm having trouble understanding how the clocks will show different times whereas the twins feel time pass at the same, normal rate in their own frames.

If all processes (clocks, biological aging, chemical processes etc.) are all 'slower' by the same amount, everything seems normal. How can you detect anything out of the ordinary?
 
  • #6
dfaullin said:
This question is in regard to special relativity.

From my rudimentary understanding, concerning the twin paradox, if one twin leaves traveling near the speed of light and returns, he will find himself younger than his twin who stayed behind. Hence, the effect of time dilation is permanent.

However, I have never read anywhere that the traveling twin's length will also be permanently adjusted due to length contraction.

How is it that one Lorentz transformed aspect remains while the other one vanishes upon the traveling twin's return?
Because it applies to different velocities (speeds). An oscillator's frequency is, apparently, dependent on its speed. So, when the traveling twin is reunited with the earthbound twin, then their clocks (and their biological oscillators) are 'keeping time' at the same rate. But while the traveling twin was traveling at a rate of speed exceeding the earthbound twin, then the periods of his clock and biological oscillators were increased. And that increase was cumulatively, and irreversibly, recorded as a slowing of time and aging.
 
  • #7
It just seems like 1 second for Twin A is the same as 1 second for Twin B. What is different is the time that Twin A sees passing for Twin B.

I think I just need to think some more about it. I need to reconsider how I view the situation in light of thinking about the distance of the traveling twin being literally less than what Earth-bound twin measures.

Thanks again for your responses.
 
  • #8
dfaullin said:
From my rudimentary understanding, concerning the twin paradox, if one twin leaves traveling near the speed of light and returns, he will find himself younger than his twin who stayed behind. Hence, the effect of time dilation is permanent.

However, I have never read anywhere that the traveling twin's length will also be permanently adjusted due to length contraction.

How is it that one Lorentz transformed aspect remains while the other one vanishes upon the traveling twin's return?
Actually, time dilation and length contraction are the same in this regard. A pair of ticks on a clock measures a uniform duration between the ticks. A pair of ticks on a rod measures a uniform distance between the ticks. While the twins are traveling both kinds of ticks are distorted. When they return to rest both kinds of ticks are undistorted.

The difference is simply that we typically keep a running total of the ticks for a clock but not for a ruler. The device which we use to keep a running total of ticks for a ruler is called an odometer. The device which we use to measure ticks of a clock without keeping a running total is called a metronome. So, the proper comparison is between clocks and odometers or between rulers and metronomes.
 
  • #9
DaleSpam said:
Actually, time dilation and length contraction are the same in this regard. A pair of ticks on a clock measures a uniform duration between the ticks. A pair of ticks on a rod measures a uniform distance between the ticks. While the twins are traveling both kinds of ticks are distorted. When they return to rest both kinds of ticks are undistorted.

The difference is simply that we typically keep a running total of the ticks for a clock but not for a ruler. The device which we use to keep a running total of ticks for a ruler is called an odometer. The device which we use to measure ticks of a clock without keeping a running total is called a metronome. So, the proper comparison is between clocks and odometers or between rulers and metronomes.
Actually a metronome produces a beat; we measure it with a frequency meter. But indeed, the comparison is between clocks and odometers as well as between rulers and frequency meters.
 
  • #10
DaleSpam said:
The difference is simply that we typically keep a running total of the ticks for a clock but not for a ruler. The device which we use to keep a running total of ticks for a ruler is called an odometer. The device which we use to measure ticks of a clock without keeping a running total is called a metronome. So, the proper comparison is between clocks and odometers or between rulers and metronomes.

I like this explanation. I think it is useful to make a direct comparison from length contraction to time dilation. If we look at age as the sum of all of the ticks on a clock, then for our length contraction to show its effects in the same way, we would have to define height as the sum of the individual's length over time. It sounds absurd right? I agree...

It is useful to treat time in this way (cumulatively), and it is not useful to treat height like this. Yet I do not think that they intrinsically differ. Hmm...well, those are just my thoughts.
 
  • #11
There's another way to look at it, as well. With time dilation what happens is that two people keep a record of time and their record differs in the end. The same would happen with distance if it was performed in a certain way. Suppose A goes to Alpha Centauri and back, and B stays on Earth. Both measure the apparent distance they travel relative to each other.

When they compare distances at the end, B says the total distance was just over 8 light years, but A says it was actually a lot less. Of course we know the reason that for A the distance to his destination was contracted when he was going fast.
 
  • #12
Elroch said:
When they compare distances at the end, B says the total distance was just over 8 light years, but A says it was actually a lot less. Of course we know the reason that for A the distance to his destination was contracted when he was going fast.

I have a question about this. Is it the distance between the planets that is contracted or the length of the spaceship that's contracted? I always assumed that both were possible, it just depended on the frame of reference. In the case that the distance between the planets is contracted, that then implies that the spaceship was stationary, and that both Earth and Alpha Centauri were moving with respect to the spaceship. This then also implies that the observer on Earth was experiencing time dilation to a greater degree than the observer on the spaceship.

Is my recollection of the events accurate?
 
  • #13
dacruick said:
I like this explanation. I think it is useful to make a direct comparison from length contraction to time dilation. If we look at age as the sum of all of the ticks on a clock, then for our length contraction to show its effects in the same way, we would have to define height as the sum of the individual's length over time. It sounds absurd right? I agree...

It is useful to treat time in this way (cumulatively), and it is not useful to treat height like this. Yet I do not think that they intrinsically differ. Hmm...well, those are just my thoughts.
Remember, length contraction occurs only along the direction of motion, so unless the traveler is laying down, it's not his height that is contracted but his thickness front to back.
 
  • #14
dacruick said:
I have a question about this. Is it the distance between the planets that is contracted or the length of the spaceship that's contracted? I always assumed that both were possible, it just depended on the frame of reference. In the case that the distance between the planets is contracted, that then implies that the spaceship was stationary, and that both Earth and Alpha Centauri were moving with respect to the spaceship. This then also implies that the observer on Earth was experiencing time dilation to a greater degree than the observer on the spaceship.

Is my recollection of the events accurate?
Yes.

Just remember that in any Frame of Reference, nothing is unusual for stationary observers/objects/clocks--it's only those things that are moving in that FoR.

So in the spaceship's FoR, the spaceship is normal but the distance between planets is contracted. In the planet's RoR, the spaceship is contracted.

Also, remember that two observers in constant relative motion directly towards or away from each other will always measure that relative speed to be the same, independent of any FoR and independent of any means by which they make the measurement.
 
  • #15
Ah, I just made a connection (in my mind)!

Light takes the shortest path through space-time. Thus, the closer you are traveling at the speed of light, the shorter your distance will be.

But now I don't understand this: You say that the distance measured by Earth-bound twin will be greater than the distance measured by traveling twin. How does Earth-bound twin measure that distance? Using a photon? Then shouldn't that measurement give the shortest possible distance, since light is taking the shortest path to the star and back?

Thanks for the great responses.

It also helps to think that the stationary observers will notice nothing unusual ever, only those things which are moving that will exhibit strange behavior. I wish I would have used this forum sooner. I bet I would have done better in Physics when I was in college. :)
 
  • #16
ghwellsjr said:
Also, remember that two observers in constant relative motion directly towards or away from each other will always measure that relative speed to be the same, independent of any FoR and independent of any means by which they make the measurement.

So if the person traveling to the other planet measures the distance to be quite small due to length contraction, and the person on Earth measures that distance to be large, how can they both measure the same speed relative to each other? Is this reconciled using time dilation?

I can understand how the spaceship traveling at let's say 0.9c has it's length contraction balanced out by the time dilation, but in what way does the spaceship observe a person standing on earth.
 
  • #17
dfaullin said:
Ah, I just made a connection (in my mind)!

Light takes the shortest path through space-time. Thus, the closer you are traveling at the speed of light, the shorter your distance will be.

But now I don't understand this: You say that the distance measured by Earth-bound twin will be greater than the distance measured by traveling twin. How does Earth-bound twin measure that distance? Using a photon? Then shouldn't that measurement give the shortest possible distance, since light is taking the shortest path to the star and back?

Thanks for the great responses.

It also helps to think that the stationary observers will notice nothing unusual ever, only those things which are moving that will exhibit strange behavior. I wish I would have used this forum sooner. I bet I would have done better in Physics when I was in college. :)
The Earth-bound twin can use light to measure the distance to the planet. He starts a timer when he sends a flash of light (it might actually be a radio signal as used in radar) which reflects off the planet and stops the timer when he receives the return signal. The distance is one half of the time interval times the speed of light. Even though the light take the shortest path, it still takes time for it to make the trip.
 
  • #18
dacruick said:
So if the person traveling to the other planet measures the distance to be quite small due to length contraction, and the person on Earth measures that distance to be large, how can they both measure the same speed relative to each other? Is this reconciled using time dilation?

I can understand how the spaceship traveling at let's say 0.9c has it's length contraction balanced out by the time dilation, but in what way does the spaceship observe a person standing on earth.
The spaceship can measure the speed that the person standing on Earth is traveling away from him by observing the Relativistic Doppler of a signal coming from Earth and calculating the speed. It will be the same Doppler and therefor the same speed that the Earth observer will measure of the spaceship.
 
  • #19
Okay, imagine this scenario.

An observer on Earth is going to measure the distance to Alpha Centauri in two ways. First, he will send a photon and calculate the distance as 1/2 ct.

Then, he will send an odometer to Alpha Centauri traveling near the speed of light (say .9c) and have it return and will take 1/2 of the odometer reading.

Which distance will be shorter?

~Dylan
 
  • #20
dfaullin said:
Okay, imagine this scenario.

An observer on Earth is going to measure the distance to Alpha Centauri in two ways. First, he will send a photon and calculate the distance as 1/2 ct.

Then, he will send an odometer to Alpha Centauri traveling near the speed of light (say .9c) and have it return and will take 1/2 of the odometer reading.

Which distance will be shorter?

~Dylan

Well, there really is no such thing as an odometer to measure travel through empty space. This is why, in my initial answer, what I posed for each twin to measure is the travel distance of the other, as they measure it. So let's say the twin A remains on Earth and measures B traveling 4 lightyears away (to some star) and back - total distance 8 ly. Assume B has traveled there at .9c. B measures A traveling away and back to B. The distance B measures for A's trip will be approx 3.5 light years (assuming 'instant turnaround'). However, as soon as B stops at Earth again and measures the distance to the star, they get 4 light years. So they say 'whoa, this relativity can be really strange'. Yes, it can.

As to how B can measure A (and the sun) distance as A travel's away and back (per B), any valid method will do (in our situation of constant speed). For example, they could use parallax with the aid of companion traveling along with them at some distance away. This modest distance (to the companion) could also be measured any convenient way (rulers, light travel time, it doesn't matter).
 
  • #21
Mind blown!
 
  • #22
dacruick said:
I have a question about this. Is it the distance between the planets that is contracted or the length of the spaceship that's contracted? I always assumed that both were possible, it just depended on the frame of reference. In the case that the distance between the planets is contracted, that then implies that the spaceship was stationary, and that both Earth and Alpha Centauri were moving with respect to the spaceship. This then also implies that the observer on Earth was experiencing time dilation to a greater degree than the observer on the spaceship.

Is my recollection of the events accurate?

To an observer on the spaceship, the rest of the Universe appears to be squashed in the direction of flight. For example, when a spaceship slows down, in the (non-inertial) decelerating frame, things in front of it can appear to be receding (and things behind it can appear to be receding as well). Of course, it is also true that, to someone observing a spaceship, it appears to be squashed along the direction of (relative) motion.
 
  • #23
PAllen said:
Well, there really is no such thing as an odometer to measure travel through empty space.
True. There can be no such thing since there is no aether. But measuring position and speed relative to the midpoint of source and destination seems a natural choice for this problem.
 
  • #24
Elroch said:
True. There can be no such thing since there is no aether. But measuring position and speed relative to the midpoint of source and destination seems a natural choice for this problem.

In a generic twin problem, there is not necessarily a well defined destination, certainly not necessarily an obvious mid point (if you consider arbitrary trajectories). The thing that seems natural and completely general for me - best stand in for an odometer - is for each twin to measure the apparent travel distance of the other twin; as I have suggested in post #3 and again in #20.
 
  • #25
WOW, this is a fun thread. What would be the difference between your brain synapsis firing at 16 frames/second, 16 frames / day or 16 frames/year? If everything is relative in your FoR absolutely nothing. Your synapsis is your internal clock for judging time. So the traveling twin’s synapsis is slowed compared to the twin on Earth. Well I suspect so are your relative metabolism and the relative cycles of all the electrons in your body. In fact they can be so slowed that if you had a magic telescope to watch your twin on Earth he would seem to move so fast you would think of him as the comic book hero the Flash. Is the distance contracted? No. Your sense of time is contracted. If you were traveling at 0.9C and a photon closing the distance towards you would be 1.9C. A photon traveling parallel with your ship would have a relative departing speed of 0.1C. Now what is physically happening and what you observe to be happening are two different things because of the speed of your synapsis and the cycling electrons in your FoR.
 
  • #26
dfaullin said:
Okay, imagine this scenario.

An observer on Earth is going to measure the distance to Alpha Centauri in two ways. First, he will send a photon and calculate the distance as 1/2 ct.

Then, he will send an odometer to Alpha Centauri traveling near the speed of light (say .9c) and have it return and will take 1/2 of the odometer reading.

Which distance will be shorter?

~Dylan
Assuming that Alpha Centauri is 4 light years away from Earth, the observer on Earth will measure 8 years for a signal to get there and back and so will calculate its distance to be 4 light years.

He can send an odometer there and back at .9c and measure the distance that way. He can make an odometer by observing the spectrum of light coming from Alpha Centauri and from the Sun prior to sending away the odometer. Then, as the odometer is traveling, it continuously measures the Relativistic Doppler coming from both stars. One will be the reciprocal of the other. (Only one is required for the measurement but I'm showing that either one or both can be used.) Assuming that one of these ratios is R, the speed of the odometer is:

β = |(1-R2)/(1+R2)

Integrating the speed over time yields distance traveled as a function of time. To make the calculation easier, we will assume that the speed is constant throughout the entire roundtrip which means that we only have to multiply the speed by the total time to get the total distance.

Now let's work out the details for our example:

At .9c, the values of R will be √[(1-β)/(1+β)] and its reciprocal. So R for Earth will be 0.2294 and for Alpha Centari will be 4.359 during the outbound portion of the trip. For the inbound portion of the trip, these numbers are exchanged.

The odometer will use the equation above to determine that β is indeed 0.9c.

Now at 0.9c, the clock on the odometer will be running slow by a factor of 1/γ. We calculate γ as 1/√(1-β2), so 1/γ = √(1-β2) which equals 0.4359. Now we need to calculate how long the trip will take. We do this first in the Earth frame as distance divided by speed which is 8 light years (round trip) divided by 0.9c which equals 8.8889 years. Now we multiply this by 1/γ to figure out what the time will be in the odometer's frame. This will be 8.8889 years times 0.4359 or 3.8747 years. This means that the total distance traveled is 3.8747 times 0.9 c or 3.4872 light years for the round trip or 1.7436 light years for the distance between Earth and Alpha Centauri. As a sanity check, this should be the distance in the Earth frame divided by γ or multiplied by 1/γ which we calculated as 0.4359. Indeed, 4 times 0.4359 is 1.7436 light years.

So to answer your question, the distance measured by the odometer is shorter.
 
  • #27
Elroch said:
PAllen said:
Well, there really is no such thing as an odometer to measure travel through empty space.
True. There can be no such thing since there is no aether. But measuring position and speed relative to the midpoint of source and destination seems a natural choice for this problem.
Well, I just showed how to make an odometer to measure travel through empty space.

And I don't understand why you base your conclusion on the idea that "there is no aether". I don't see the connection.

I also don't understand your comments about "the midpoint of the source and destination".
 
  • #28
Qzit said:
WOW, this is a fun thread. What would be the difference between your brain synapsis firing at 16 frames/second, 16 frames / day or 16 frames/year? If everything is relative in your FoR absolutely nothing. Your synapsis is your internal clock for judging time. So the traveling twin’s synapsis is slowed compared to the twin on Earth. Well I suspect so are your relative metabolism and the relative cycles of all the electrons in your body. In fact they can be so slowed that if you had a magic telescope to watch your twin on Earth he would seem to move so fast you would think of him as the comic book hero the Flash. Is the distance contracted? No. Your sense of time is contracted. If you were traveling at 0.9C and a photon closing the distance towards you would be 1.9C. A photon traveling parallel with your ship would have a relative departing speed of 0.1C. Now what is physically happening and what you observe to be happening are two different things because of the speed of your synapsis and the cycling electrons in your FoR.
WOW, I think you're having too much fun. A lot of erroneous ideas here.

What do you mean that there is no difference between 16 frames per second, day or year? It is true that all processes, including biological will be slowed down for the traveling twin, as determined by the rest frame of the Earth, but the traveling twin will also determine that the Earth twin is the one that is experiencing time dilation according to his own rest frame. And you're also mixed up on the speed of a photon being 1.9c or 0.1c according to the traveling twin. I suggest that you do a lot of reading or asking questions instead of trying to answer them until you get yourself up on the learning curve.
 
  • #29
ghwellsjr said:
Well, I just showed how to make an odometer to measure travel through empty space.

And I don't understand why you base your conclusion on the idea that "there is no aether". I don't see the connection.

I also don't understand your comments about "the midpoint of the source and destination".
I also wondered about that... My 2 cts: There are no mechanical odometers; I suppose that what was meant, is that there is no material ether on which we could let an odometer roll. Note also that if we could, then any odometer would measure "absolute" lengths, for the wheel is at rest wrt the road at the point of contact!

And I think that the midpoint of source and destination depends on the reference system for two twins in arbitrary motion.
 
  • #30
ghwellsjr
I think you were reading with your mind and not your eyes. You would not perceive a difference in time out in space if your relative synapsis fired 16 times a second, a day or a year. My other question to you is what is the closing speed between two photons traveling on a collision course? This was not in reference to the traveling twin. Of course the traveling twin would see it differently with his clock slowed.
 
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  • #31
ghwellsjr said:
WOW, I think you're having too much fun. A lot of erroneous ideas here.What do you mean that there is no difference between 16 frames per second, day or year? It is true that all processes, including biological will be slowed down for the traveling twin, as determined by the rest frame of the Earth, but the traveling twin will also determine that the Earth twin is the one that is experiencing time dilation according to his own rest frame. And you're also mixed up on the speed of a photon being 1.9c or 0.1c according to the traveling twin. I suggest that you do a lot of reading or asking questions instead of trying to answer them until you get yourself up on the learning curve.

I can't see one in his/her post. Could you be more specific since your are being so bold.

The closing distance comment is fairly accurate (#'s aren't). The concept is definately right (excluding the "distance" contraction / "time contraction" comment).

Of course the 16 seconds, days, year comment is referring to time dilation. I am pretty sure you understand that. It means there is no difference in the traveling observers perception of time passing (tick tock / proper time ect) to that of an observer who is at "rest".

I suggest that you do a lot of reading or asking questions instead of trying to answer them until you get yourself up on the learning curve.

Nice ain't it?

You've helped me improve my understanding of SR on a number of occasions ghwellsjr, it is a shame to see you post a reply like that. When I know you are capable of getting Qzit's interpretations on a more defined track / train of thought.
 
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  • #32
nitsuj said:
I can't see one in his/her post.
I don't know which ones ghwellsjr noticed, but I saw a few that were either wrong or only conditionally right:

Qzit said:
WOW, this is a fun thread. What would be the difference between your brain synapsis firing at 16 frames/second, 16 frames / day or 16 frames/year? If everything is relative in your FoR absolutely nothing. Your synapsis is your internal clock for judging time. So the traveling twin’s synapsis is slowed compared to the twin on Earth. Well I suspect so are your relative metabolism and the relative cycles of all the electrons in your body.
So far everything is fine.

Qzit said:
In fact they can be so slowed that if you had a magic telescope to watch your twin on Earth he would seem to move so fast you would think of him as the comic book hero the Flash.
This would be true on the return journey, but false on the outward journey.

Qzit said:
Is the distance contracted? No.
False. Distance is contracted too.

Qzit said:
Your sense of time is contracted. If you were traveling at 0.9C and a photon closing the distance towards you would be 1.9C. A photon traveling parallel with your ship would have a relative departing speed of 0.1C.
True only in the Earth frame.

Qzit said:
Now what is physically happening and what you observe to be happening are two different things because of the speed of your synapsis and the cycling electrons in your FoR.
This is a LET interpretation, not a SR interpretation. However, interpretations cannot be experimentally proven one way or the other, so I have no objection other than a kind of general distaste for LET as a pet theory of crackpots.
 
  • #33
Yes Dalespam I understand your point and even ghwellsjr's point. This forum like's to be techincaly right, which is awsome and separates a poor quality physics forum from a great one. Leaving out discussions about biology, conciousness and the sorts is important to point out because of the add difficulty of interpretation among other things.

But do you understand my point?

Qzit's interpretations are not flat out wrong, they are poorly defined. This is a big difference if someone is going to call those interpretations as erroneous. Said differently a lot of Qzits interpretations are correct, ghwellsjr implied most were wrong. In a sense, possibly pushing Qzit further down the learning curve.

I wouldn't have an issue if ghwellsjr replied pointing out the technicalities, like you did.

And yes, as I noticed too (a layman of SR) the "distance" contraction isn't right. Big deal, point it out and say good for you in noticing the impact of closing distances. So one wrong comment.

Your last comment, if I understand right, yes if Qzit wants to stay "true" to SR (or physics in general), the "reality" is the observation (measurement +calculation). But it is merely a prefference, and not crackpottery.
 
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  • #34
nitsuj said:
Do you understand mine?

Qzit's interpretations are not flat out wrong, they are poorly defined.
Yes, I understand your point. Only the one comment was flat out wrong, the rest could be either wrong or right depending on the "poorly defined" details.
 
  • #35
nitsuj said:
Your last comment, if I understand right, yes if Qzit wants to stay "true" to SR (or physics in general), the "reality" is the observation (measurement +calculation). But it is merely a prefference, and not crackpottery.
Let me clarify my intention.

DaleSpam said:
Qzit said:
Now what is physically happening and what you observe to be happening are two different things because of the speed of your synapsis and the cycling electrons in your FoR.
This is a LET interpretation, not a SR interpretation. However, interpretations cannot be experimentally proven one way or the other, so I have no objection other than a kind of general distaste for LET as a pet theory of crackpots.
In LET it is true that what is physically happening and what you observe to be happening are two different things. In LET as you move relative to the aether your lengths contract and times dilate such that the measurements you make are incorrect. Specifically, your coordinate time is an incorrect measure of the aether coordinate time, and so forth. Only the physics in the aether frame are "physically happening".

On the other hand, in SR every reference frame is equally valid. So both of our observations are equally valid observations of what is physically happening. The disagreements between our observations are not because one of us "distorted" and the other is not but rather simply because we are each observing the same physics from different but valid perspectives. In this view, your coordinate time is a correct measure of the proper time, and so forth.

Both of the above interpertations are valid, and in principle I have no problem with the LET interpretation. However, most of the proponents of LET that I have encountered are crackpots and my interactions with them are usually fairly unpleasant. So I have a certain "guilt by association" distaste for LET. I was not calling Qzit a crackpot nor even implying it, merely expressing the source of my distaste for LET.
 
<h2>1. Why do the effects of Time Dilation last forever?</h2><p>The effects of Time Dilation are caused by the relationship between an object's speed and the passage of time. As an object approaches the speed of light, time slows down for that object. This means that the object experiences time at a slower rate than a stationary observer. This effect is permanent because it is a fundamental aspect of the universe and cannot be reversed.</p><h2>2. How is Length Contraction different from Time Dilation?</h2><p>Length Contraction is the phenomenon where an object's length appears to decrease as it moves closer to the speed of light. This is due to the fact that the object's mass increases as it approaches the speed of light, causing it to become more compact. Unlike Time Dilation, the effects of Length Contraction are not permanent and can be reversed once the object returns to a slower speed.</p><h2>3. Why is Time Dilation considered a permanent effect?</h2><p>Time Dilation is considered a permanent effect because it is a fundamental aspect of the universe and is a result of the relationship between an object's speed and the passage of time. As an object approaches the speed of light, time slows down for that object. This means that the object will always experience time at a slower rate than a stationary observer, regardless of its speed.</p><h2>4. Can the effects of Time Dilation be reversed?</h2><p>No, the effects of Time Dilation cannot be reversed. This is because they are a fundamental aspect of the universe and are a result of the relationship between an object's speed and the passage of time. As an object approaches the speed of light, time slows down for that object, and this effect cannot be reversed or undone.</p><h2>5. Why is Length Contraction not a permanent effect?</h2><p>Length Contraction is not a permanent effect because it is a result of an object's mass increasing as it approaches the speed of light. Once the object returns to a slower speed, its mass decreases and its length returns to its original size. Unlike Time Dilation, which is a fundamental aspect of the universe, Length Contraction is a result of an object's speed and can be reversed once the object's speed changes.</p>

1. Why do the effects of Time Dilation last forever?

The effects of Time Dilation are caused by the relationship between an object's speed and the passage of time. As an object approaches the speed of light, time slows down for that object. This means that the object experiences time at a slower rate than a stationary observer. This effect is permanent because it is a fundamental aspect of the universe and cannot be reversed.

2. How is Length Contraction different from Time Dilation?

Length Contraction is the phenomenon where an object's length appears to decrease as it moves closer to the speed of light. This is due to the fact that the object's mass increases as it approaches the speed of light, causing it to become more compact. Unlike Time Dilation, the effects of Length Contraction are not permanent and can be reversed once the object returns to a slower speed.

3. Why is Time Dilation considered a permanent effect?

Time Dilation is considered a permanent effect because it is a fundamental aspect of the universe and is a result of the relationship between an object's speed and the passage of time. As an object approaches the speed of light, time slows down for that object. This means that the object will always experience time at a slower rate than a stationary observer, regardless of its speed.

4. Can the effects of Time Dilation be reversed?

No, the effects of Time Dilation cannot be reversed. This is because they are a fundamental aspect of the universe and are a result of the relationship between an object's speed and the passage of time. As an object approaches the speed of light, time slows down for that object, and this effect cannot be reversed or undone.

5. Why is Length Contraction not a permanent effect?

Length Contraction is not a permanent effect because it is a result of an object's mass increasing as it approaches the speed of light. Once the object returns to a slower speed, its mass decreases and its length returns to its original size. Unlike Time Dilation, which is a fundamental aspect of the universe, Length Contraction is a result of an object's speed and can be reversed once the object's speed changes.

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