[Bart]

Janus, on 12 November 2011 - 07:09 PM, said:

1.His first argument is something we've already gone over and is easy to dismiss by the actual results from accelerator experiments. If the argument was true, particles leaving the accelerator would have much less energy than predicted by Relativity. Since we can measure the energy of these particles after they leave the accelerator and their energies equals those predicted by Relativity, the argument fails in the face of the physical evidence.

2. It is like arguing that rockets won't work in the vacuum of space because they would have nothing to push against. No matter how much you may believe that your argument is correct, the fact that real rockets in the real world do work in space makes it a pointless argument.


3. The second argument trying to link relativistic mass increase and length contraction is just silly. The idea that the density of the mass as viewed from different frames, must remain the same is misguided.

1. "Any number of experiments can not prove that I'm right: one experiment may show that I am wrong ". A. Einstein

2. A rocket is propeled by its own jet engine and not by an external system like protons in accelerators, so the above comparison is wrong.

3. What then is the formula for the increase of relativistic mass density? Does the density of mass can grow in a different proportion than the contraction?

This post has been edited by Bart: 5 December 2011 - 12:53 PM

[Janus]

Bart, on 5 December 2011 - 12:50 PM, said:

1. "Any number of experiments can not prove that I'm right: one experiment may show that I am wrong ". A. Einstein

And experiment has shown the argument put forth by the author of the page to be wrong.
If experiment does ever uncover a flaw in Relativity, It will not mean a reversion to Newtonian physics, because experiment has already shown that to be flawed. Any new theory supplanting Relativity would have to account for all observation made to date.

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2. A rocket is propeled by its own jet engine and not by an external system like protons in accelerators, so the above comparison is wrong.

You missed the point. I was not comparing rockets and particle accelerators in the physics sense. I was pointing out that both the argument made by the author and the argument against rockets were alike in that they both are based on misconception and are demonstratively wrong.

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3. What then is the formula for the increase of relativistic mass density? Does the density of mass can grow in a different proportion than the contraction?

Assuming that the idea of relativistic mass density is a valid concept, You would simply take the relativistic mass of the object per the gamma relationship divided by the volume per length contraction. Thus if the relative speed is 0.886 c, the length and thus the volume would halve, and the relativistic mass double, giving 4 times the density.

[Bart]

Janus, on 5 December 2011 - 05:04 PM, said:

Assuming that the idea of relativistic mass density is a valid concept, You would simply take the relativistic mass of the object per the gamma relationship divided by the volume per length contraction. Thus if the relative speed is 0.886 c, the length and thus the volume would halve, and the relativistic mass double, giving 4 times the density.

Then if the relative speed is 0.9999 c, the length and thus the volume would be contracted 70 times, and the relativistic mass increases 70 times, giving 5000 times the density.


1. What will happen then with the Mendeleev's Periodic Table of Elements?

2. What will be the speed of light, eg in air or water, when its density increases 5,000 times?

3. What will happen with the air pressure in the cabin of the rocket and what happens to the rocket itself, when the density of the rocket and air contained therein will grow 5,000 times ?

This post has been edited by Bart: 5 December 2011 - 07:39 PM

[swansont]

Bart, on 5 December 2011 - 07:33 PM, said:

Then if the relative speed is 0.9999 c, the length and thus the volume would be contracted 70 times, and the relativistic mass increases 70 times, giving 5000 times the density.


1. What will happen then with the Mendeleev's Periodic Table of Elements?

2. What will be the speed of light, eg in air or water, when its density increases 5,000 times?

3. What will happen with the air pressure in the cabin of the rocket and what happens to the rocket itself, when the density of the rocket and air contained therein will grow 5,000 times ?

In the rest frame, nothing at all happens.

[Janus]

Bart, on 5 December 2011 - 07:33 PM, said:

Then if the relative speed is 0.9999 c, the length and thus the volume would be contracted 70 times, and the relativistic mass increases 70 times, giving 5000 times the density.


1. What will happen then with the Mendeleev's Periodic Table of Elements?

2. What will be the speed of light, eg in air or water, when its density increases 5,000 times?

3. What will happen with the air pressure in the cabin of the rocket and what happens to the rocket itself, when the density of the rocket and air contained therein will grow 5,000 times ?

As pointed out, nothing. In the rest frame of the rocket nothing has changed. In the frame where the rocket has a relative speed of 0.9999 c, The rocket behaves as a version of the rest frame that is shorter, time runs slower, and has a different notion of simultaneity. IOW, nothing untoward happens to the rocket (the rocket doesn't balloon out from increased pressure, etc) in the rest frame or any other.

Don't think about Relativistic effects as something that actively compresses objects or forces their internal movements to slow down.

Relativistic effects are just due to the fact that different inertial frames view and measure time and space differently from each other.

This post has been edited by Janus: 6 December 2011 - 12:18 AM

[Bart]

Janus, on 6 December 2011 - 12:17 AM, said:

As pointed out, nothing. In the rest frame of the rocket nothing has changed. In the frame where the rocket has a relative speed of 0.9999 c, The rocket behaves as a version of the rest frame that is shorter, time runs slower, and has a different notion of simultaneity. IOW, nothing untoward happens to the rocket (the rocket doesn't balloon out from increased pressure, etc) in the rest frame or any other.

Don't think about Relativistic effects as something that actively compresses objects or forces their internal movements to slow down.

Relativistic effects are just due to the fact that different inertial frames view and measure time and space differently from each other.

Thanks for your comments. I am now totally confused in these Earth explanations.

As apassenger, I now travel a rocket at a constant speed 0.98 c in relation to the Earth and I do not feel for this reason, any changes in my surroundings here. Just as on the Earth, I still have 180cm height and 80kg mass, my soccer ball is still round, and my dumbbells have weight 5kg. The only difference is that I see you on the Earth in a more red color due to your fast moving away from me (Doppler effect) and I hear your radio broadcasts more and more delayed, which is also understandable because of the increasing distance.

But I hear, that you there on the Earth, you say that my mechanical watch is five times slower than on Earth, and that I have now only 30 cm tall, that I have a mass of 400kg, that my soccer ball has now become a rugby ball, and my dumbbells have a mass of 25 kg and which I still brandishes as fast as on Earth. Is it in your view, that my strength also increased 5 times?

Neither you on the Earth nor I in the rocket are able to determine who of us is at rest and who is moving at speed of 0.98 c. We move away from each other with the speed 0,98c and that's all.

Neither your seeing me and not my seeing you, has no effect on the actual physical state of whoever of us. The relativistic effects are just an illusion, caused by the limited speed of transmission of the information (light speed). If we ever find a data transmission method much faster than light , then the present illusion at the speed of light will disappear, and the current supposed evidence of mass increase, time dilation,etc. prove to be only a measurement or interpretive errors.

I believe that sooner or later it will happen.

This post has been edited by Bart: 6 December 2011 - 07:07 PM

[Schrödinger's hat]

Bart, on 6 December 2011 - 07:02 PM, said:

The relativistic effects are just an illusion, caused by the limited speed of transmission of the information (light speed). If we ever find a data transmission method much faster than light , then the present illusion at the speed of light will disappear, and the current supposed evidence of mass increase, time dilation,etc. prove to be only a measurement or interpretive errors.

I believe that sooner or later it will happen.

This is most certainly not the case. If I do not correct for light delay there will be further distortions, but they are location dependant.
If you were moving towards me you would actually appear stretched.
Any experiment I do (including momentarily trapping you in a container as long as I open the doors in time to let you out) will show your size in one dimension to be smaller.
This is all a relic of us having a different definition of what constitutes time and space. If you consider all four dimensions, then the analogue of length (interval) remains constant

[Janus]

Bart, on 6 December 2011 - 07:02 PM, said:

Thanks for your comments. I am now totally confused in these Earth explanations.

As apassenger, I now travel a rocket at a constant speed 0.98 c in relation to the Earth and I do not feel for this reason, any changes in my surroundings here. Just as on the Earth, I still have 180cm height and 80kg mass, my soccer ball is still round, and my dumbbells have weight 5kg. The only difference is that I see you on the Earth in a more red color due to your fast moving away from me (Doppler effect) and I hear your radio broadcasts more and more delayed, which is also understandable because of the increasing distance.

But I hear, that you there on the Earth, you say that my mechanical watch is five times slower than on Earth, and that I have now only 30 cm tall, that I have a mass of 400kg, that my soccer ball has now become a rugby ball, and my dumbbells have a mass of 25 kg and which I still brandishes as fast as on Earth. Is it in your view, that my strength also increased 5 times?

No. If I , On Earth calculate the energy you expend moving a weight according to what I measure I will calculate the same energy that you calculated that you spent. I jut have to make sure that I apply [i]all[/] the rules of SR properly. For example: if you accelerated a mass forward by 0.001c, as measured by you, by the rules of Relativistic velocity addition I would only see a change in the velocity of the mass change by 0.0004c.

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Neither you on the Earth nor I in the rocket are able to determine who of us is at rest and who is moving at speed of 0.98 c. We move away from each other with the speed 0,98c and that's all.

Neither your seeing me and not my seeing you, has no effect on the actual physical state of whoever of us. The relativistic effects are just an illusion, caused by the limited speed of transmission of the information (light speed). If we ever find a data transmission method much faster than light , then the present illusion at the speed of light will disappear, and the current supposed evidence of mass increase, time dilation,etc. prove to be only a measurement or interpretive errors.

I believe that sooner or later it will happen.

It must be wonderful to be able to just claim that anything that "confuses you" is wrong. Do you reserve this right to just yourself, or can others use it? Imagine the joy of all those school children confused by fractions that can now just claim that the whole idea of fractions is just wrong.

[ravell]

Janus, on 6 December 2011 - 12:17 AM, said:

As pointed out, nothing. In the rest frame of the rocket nothing has changed. In the frame where the rocket has a relative speed of 0.9999 c, The rocket behaves as a version of the rest frame that is shorter, time runs slower, and has a different notion of simultaneity. IOW, nothing untoward happens to the rocket (the rocket doesn't balloon out from increased pressure, etc) in the rest frame or any other.

Don't think about Relativistic effects as something that actively compresses objects or forces their internal movements to slow down.

Relativistic effects are just due to the fact that different inertial frames view and measure time and space differently from each other.

If in the rest frame of the rocket nothing has changed, then how we can reliably confirm that mass of the protons moving in the LHC, at speed of 0.999999 c is increased?



The experiments in the LHC accelerator are being performed in a single frame of reference. The source of the protons, the accelerator, and the device which measures the speed of protons and their energy (and the staff) are all at rest with respect to each other.

This post has been edited by ravell: 6 March 2012 - 06:14 PM

[Janus]

ravell, on 6 March 2012 - 06:13 PM, said:

If in the rest frame of the rocket nothing has changed, then how we can reliably confirm that mass of the protons moving in the LHC, at speed of 0.999999 c is increased?



The experiments in the LHC accelerator are being performed in a single frame of reference. The source of the protons, the accelerator, and the device which measures the speed of protons and their energy (and the staff) are all at rest with respect to each other.

But the protons aren't, they are moving at 0.999999c with respect to the LHC. In the rest frame of the protons, you would measure no difference in terms of their mass, but to measure their mass in their rest frame, you would have to yourself moving at 0.999999c with respect to the LHC. Though to be accurate, They really don't talk about the mass the protons changing, as "mass" generally refers to the proper or invariant mass. Instead it is said that the kinetic energy of the protons increase asymptotically as the speed of the photons approach c. This is different from Newtonian physics which predicts an exponential increase which approaches infinity as the speed approaches infinity.

It really isn't any different than measuring the KE of a moving object with Newtonian physics, the an object's KE with respect to itself is 0, what we measure is its KE from is a frame which it is moving with respect to. One way is to smack it into a target and see what happens. The whole point is that Newtonian physics predict one result and Relativity predicts another. The results we get from such experiments give results that agree with Relativity.

[ravell]

Janus, on 6 March 2012 - 08:11 PM, said:

But the protons aren't, they are moving at 0.999999c with respect to the LHC. In the rest frame of the protons, you would measure no difference in terms of their mass, but to measure their mass in their rest frame, you would have to yourself moving at 0.999999c with respect to the LHC. Though to be accurate, They really don't talk about the mass the protons changing, as "mass" generally refers to the proper or invariant mass. Instead it is said that the kinetic energy of the protons increase asymptotically as the speed of the photons approach c. This is different from Newtonian physics which predicts an exponential increase which approaches infinity as the speed approaches infinity.

It really isn't any different than measuring the KE of a moving object with Newtonian physics, the an object's KE with respect to itself is 0, what we measure is its KE from is a frame which it is moving with respect to. One way is to smack it into a target and see what happens. The whole point is that Newtonian physics predict one result and Relativity predicts another. The results we get from such experiments give results that agree with Relativity.

Thank you Sir for your response. In such a case it is possible to create in the laboratory a closed ball, inside which will be installed a mini accelerator, enabling acceleration of particles to the speed of light, and thus we'll be able to arbitrarily increase the mass of this ball. The rest mass of the ball in the laboratory will be then variable and will depend on the tricks performed by us inside the ball. Is it so?

[swansont]

ravell, on 8 March 2012 - 02:49 PM, said:

The rest mass of the ball in the laboratory will be then variable

Not sure what you mean by this. Rest mass won't change as the ball changes speed.

[Janus]

ravell, on 8 March 2012 - 02:49 PM, said:

Thank you Sir for your response. In such a case it is possible to create in the laboratory a closed ball, inside which will be installed a mini accelerator, enabling acceleration of particles to the speed of light, and thus we'll be able to arbitrarily increase the mass of this ball. The rest mass of the ball in the laboratory will be then variable and will depend on the tricks performed by us inside the ball. Is it so?

So let me get this straight, you have a self enclosed system which consists of mini-accelerator capable of accelerating particle up to near light speed, which is enclosed in a ball sitting in a larger lab. You are asking if the apparent mass of this ball would appear to change as measured from the outside lab frame as the mini-accelerator brought particles up to near light speed. As long as the "lab in a ball" is a closed system (contains its own energy source), then the answer is no.

The energy stored in the ball that is used to run the accelerator and accelerate the particles is already there. it already contributes to the balls "relativistic mass". Converting this energy to kinetic energy in the form of moving particles does not change its contribution. As long as the system remains closed,(no energy in or out), the "apparent mass" as measured in the outer lab remains unchanged.

[ravell]

Janus, on 6 December 2011 - 12:17 AM, said:

As pointed out, nothing. In the rest frame of the rocket nothing has changed. In the frame where the rocket has a relative speed of 0.9999 c, The rocket behaves as a version of the rest frame that is shorter, time runs slower, and has a different notion of simultaneity. IOW, nothing untoward happens to the rocket (the rocket doesn't balloon out from increased pressure, etc) in the rest frame or any other.

Don't think about Relativistic effects as something that actively compresses objects or forces their internal movements to slow down.

Relativistic effects are just due to the fact that different inertial frames view and measure time and space differently from each other.

One more question Sir. If in the rest frame of the rocket does not change anything, so I do not understand why in the Michelson- Morley experiment, to explain the achieved equal round trip time for the light beams in the arms of the interferometer, the Fitzgerald-Lorentz contraction has been applied, for the arm parallel to the movement of earth (rocket). All equipment used in the MM experiment, were after all in a single frame of reference and were at rest with respect to each other.

[Janus]

ravell, on 9 March 2012 - 07:12 PM, said:

One more question Sir. If in the rest frame of the rocket does not change anything, so I do not understand why in the Michelson- Morley experiment, to explain the achieved equal round trip time for the light beams in the arms of the interferometer, the Fitzgerald-Lorentz contraction has been applied, for the arm parallel to the movement of earth (rocket). All equipment used in the MM experiment, were after all in a single frame of reference and were at rest with respect to each other.

You are confusing Lorentzian Relativity and Special Relativity.

Lorentz tried to preserve the idea of the aether by proposing that movement through it caused clocks to run slow and objects to contract. He came up with the equations that we still name after him to describe this, however his derivation was basically ad-hoc. They worked just because he chose equations that would.

Einstein took a different approach. He showed that you could derive the same equations from two simple postulates which did not rely on the existence of an aether. With SR, the equations do not deal with effects caused by absolute motion( which SR denies) but with transforming between frames with relative motion. They describe what you measure as happening to a frame moving with respect to you. You never apply the Lorentz contractions to your own frame because it is at rest with respect to you. So, in SR the reason You get equal round trip times for the Michelson_ Morley experiment is that, as far as the apparatus is concerned, there is no difference between it being at rest or moving. It would only be someone that the apparatus was moving with respect to that would apply the Lorentz contractions to the apparatus in order to explain the equal round trip times.