I Is it only experience that's relative?

[Elimelech70]

TL;DR Summary

Reading Einstein Relativity and the trains experiences lightening strikes differently to the embankment. Does it show experience is relative and time is finite, so is not a perfect measure?

Reading Einstein Relativity. The trains experiences lightening strikes differently to the embankment. So the two events are experienced differently from the two reference points because they have different distances to the events. Light from the events taking different times to reach each reference point due to different distances. It shows a reference point's proximity to the two different events will result in different experence due to the speed of light being finite. It does not represent time in a way that shows it to be relative, just that experience of events due to lights time to reach. The only way to prove simultaneity would be to use a measure that is instant rather that is finite like light. So is time relative, I am not convinced it has proven it.

 

[PeroK]

TL;DR Summary: Reading Einstein Relativity and the trains experiences lightening strikes differently to the embankment. Does it show experience is relative and time is finite, so is not a perfect measure?

Reading Einstein Relativity. The trains experiences lightening strikes differently to the embankment.

I must confess I don't like that Einstein thought experiment. I think it's very confusing.

So the two events are experienced differently from the two reference points because they have different distances to the events. Light from the events taking different times to reach each reference point due to different distances. It shows a reference point's proximity to the two different events will result in different experence due to the speed of light being finite.

The finite speed of light and the delay in light signals from an event reaching an observer is not what the theory of Relativity depends on. In fact, the first estimate of the speed of light (by Roemer in 1676) used the delay in light signals from one of Jupiter's moons:

https://en.wikipedia.org/wiki/Rømer's_determination_of_the_speed_of_light

This delay in signals always was part of the observational calculations in Newtonian physics.

It's a common misconception that relativity somehow depends on the finite speed of light.

It does not represent time in a way that shows it to be relative, just that experience of events due to lights time to reach. The only way to prove simultaneity would be to use a measure that is instant rather that is finite like light. So is time relative, I am not convinced it has proven it.

The historical development of the theory of relativity depends on the speed of light being invariant. That means a light signal is measured to have the same speed in all inertial frames of reference. This is quite simply incompatible with absolute space and time. I.e. incompatible with Newtonian physics.

The only alternative is Special Relativity.

To determine the issue you need an experiment. Relativity predicts that no particle can travel faster than the speed of light. If you design a particle accelerator and accelerate particles to high energies, then that should resolve the issue. If the particles get accelerated beyond the speed of light, then relativity would be wrong.

But, of course, when particles are accelerated at CERN (or any other experimental centre), not only is their speed limited by the speed of light, but all the other predictions of relativity are seen: energy-momentum equations and $E = mc^2$ etc.

 

[Ibix]

So is time relative, I am not convinced it has proven it.

The point of the experiment is that both the train observer and the platform observer say that the flashes were emitted the same distance from them, but one receives the flashes at the same time and one does not. If the postulate that the speed of light is the same in both frames is true, reasoning backwards from what they see leads one to conclude that the flashes must have been simultaneous and the other to conclude that they were not.

We are not making the mistake of saying "if I see two flashes of light arrive at the same time they are simultaneous". We are using our knowledge of the setup to reason about the emission of the flashes based on the reception times and travel distances.

 

[anuttarasammyak]

Everything is relative but relative ones are under definite transformation. I think this is the essence of relativity.

 

[Dale]

It does not represent time in a way that shows it to be relative, just that experience of events due to lights time to reach.

Actually, it does show that time is relative. The finite speed of light, what you call “experience of events due to lights time to reach”, is fully accounted for in the analysis. The relativistic effects are what remains after correctly accounting for experience.

The only way to prove simultaneity would be to use a measure that is instant rather that is finite like light.

And what if there is no such thing? How should simultaneity be established in a hypothetical universe where there is nothing that travels instantly but there is something that always travels at a known speed?

 

[FactChecker]

TL;DR Summary: Reading Einstein Relativity and the trains experiences lightening strikes differently to the embankment. Does it show experience is relative and time is finite, so is not a perfect measure?

Time is just not as simple as previously thought. Special Relativity gives the exact formula for converting elapsed time in one reference frame to another, so it is still a very good, essential, measure. You should be aware that there is never enough disagreement about elapsed time so that one frames "cause - effect" time sequencing is reversed in another frame.

Reading Einstein Relativity. The trains experiences lightening strikes differently to the embankment. So the two events are experienced differently from the two reference points because they have different distances to the events. Light from the events taking different times to reach each reference point due to different distances. It shows a reference point's proximity to the two different events will result in different experence due to the speed of light being finite.

Correct.

It does not represent time in a way that shows it to be relative, just that experience of events due to lights time to reach. The only way to prove simultaneity would be to use a measure that is instant rather that is finite like light.

No. Simultaneity is also relative. Different reference frames determine "simultaneous" differently. Although it is a fundamental fact of SR, the relativity of simultaneity is the most often overlooked fact by people who are stumped by a claimed SR "paradox".

So is time relative, I am not convinced it has proven it.

Experimental results "proved" it, not the logic of a theory. The SR theory was a way of explaining some experimental results. Many people hated the idea of elapsed time being relative but they could never explain some known experimental results. The experimental evidence became overwhelming and undeniable.

 

[Sagittarius A-Star]

So is time relative, I am not convinced it has proven it.

Time is relative. Maybe you can better understand the related scenario of Morin.
A light flash happens in the middle of a train.

• In the train-frame ($A$, figure 1.9), the light hits both ends of the train simultaneously.
• In the embankment-frame ($B$, figure 1.10), the light hits first the rear end of the train and then the front end of the train.

Source:
https://scholar.harvard.edu/files/david-morin/files/relativity_chap_1.pdf

via:
https://scholar.harvard.edu/david-morin/special-relativity

 

[Elimelech70]

Special Relativity shows the limit of the speed of light giving different experiences based on spacetime. Does it prove time is not absolute, or just that light takes different times to get to two different points separated by different spacetime measures?

If we had matter at point A and another piece of matter at point B. The spacetime between them is unknown.
We have reference point C with a piece of matter 'a' entangled with the piece of matter at point A. Also, we have matter 'b' at location C entangled with matter at point B. So point C has 'a' and 'b' in the same proximity with no timespace separation.

We now have events at A and B referenced a point C immediately due to the fact that the two pieces of matter 'a' and 'b' are entangled to the matter at the points A and B. Events experience at C no longer determined by the finite speed of light.

Events happening at A and B affect 'a' and 'b' immediately, not requiring light to travel to C and give the appearance of a different spacetime experience. C can experience events as they happen. The experience of events at both A and B will be experienced at C as they happen at A and B through entangled 'a' and 'b' because entanglement means events experienced at C as they happen at A and B.

So let's say Einstein could get the special weatherman to get lightning to strike A and B at the same moment. C would experience the immediately through 'a' and 'b' due to entanglement not being limited by the speed of light. Special relativity, the proof that experience is limited by the speed of light is no longer relevant. So does instant experience through entangled matter question the special relativity concept that time is not absolute? Time is a measurement of the experience of events. If a finite constant such as light is used to measure the difference in experience of course experience is different due to different spacetime. But not if experience is instant when measured through instant entanglement is time therefore absolute for entangled matter?

 

[PeroK]

Special Relativity shows the limit of the speed of light giving different experiences based on spacetime ...

Your post makes no scientific sense. It's more a stream of consciousness than physics.

 

[Elimelech70]

if entanglement means experience is immediate between the entangled pieces of matter, then we don't need light to be the 'time delayed' conveyor of experience. If we don't relay on the speed of time, special relativity is no longer important. Time just is and the experience is immediate not time delayed.

 

[Elimelech70]

Finite measures like light even if constant in a vacuum is not proof that time is not absolute.

 

[Doc Al]

This thread has gone on long enough. Note: Personal theories are not permitted.