Relation of time and speed of light

[michel123456]

 

 

Yes, precisely. Information transfer would happen instantaneously, which is a viable solution. Other than nature doesn't happen to work that way.

More than that. If a single particle can be at different points of space at the same instant it poses a question about what "is" that make a particle unique.

What is the thing that makes a particle different from another? It is that a particle occupies a space at a certain instant. If a particle occupies 2 different places at the same time, it is not unique anymore. It gets then the property of ubiquity.

Edited June 16, 2016 by michel123456

[swansont]

More than that. If a single particle can be at different points of space at the same instant it poses a question about what "is" that make a particle unique.

What is the thing that makes a particle different from another? It is that a particle occupies a space at a certain instant. If a particle occupies 2 different places at the same time, it is not unique anymore. It gets then the property of ubiquity.

 

 

Classically, a particle can't be at different points at the same time, so this is all moot, isn't it? We're discussing relativity here. Even under Einstein's relativity (i.e. finite c), a particle does not occupy more than one point at a time. So I'm still not seeing how you are getting this — you seem to be assuming the answer, rather than concluding it from other principles.

[TakenItSeriously]

"Just a theory" is a red flag of a phrase in a science discussion. It suggests you don't understand what a theory is, in a scientific context. (it doesn't mean guess, it doesn't mean untested)

I'm not sure how that comment applies to my understanding of what a theory is.

 

I did misunderstand the derivations for Planck numbers was what linked their values in the first place, which was never an issue for me as an engineer.

 

So When Imatfal's, mentioned that time and distance were equal for planc units, at first, I didn't notice that it was due to how they were derived and I erroneously initially thought the matching numbers proved the link of space and time which made me question why it wasn't considered a law or principle. though I corrected that oversight a minute later.

 

Perhaps I should have deleted the erroneous statement but I'm in the habit of forums permanently reflecting errors in posts. So I added corrections for the comment instead of replacing it which may have confused you somehow? IDK.

 

 

I can assure you that I have a pretty solid understanding of what qualifies a theory now vs what may have been required earlier and why the shift in requirements is important.

 

It essentially amounts to validating a new theory vs adding new portions of theory for completing a theory.

 

Solving problems that existing theories fail to solve while remaining consistent within the complex set of theories already vetted over time is self vetting for the most part. It is the complexity and the broad range of vetted theories that it needs to conform to that makes solving multiple problems, while conforming to known data and doing it in a consistent manner a very difficult task to achieve with an invalid theory.

 

It's just fitting too many variables that makes it self validating like matching 15 points on a finger print.

Edited June 16, 2016 by TakenItSeriously

[disarray]

Strange: You write that "This entangled "thing" can be spread over half the universe, but that's OK because quantum effects are inherently non-local anyway (in time and space)."

 

From what I gather, the idea that an 1) electron's field can span great distances and that 2) that two entangled particles become a single particle until observed is a fairly recent concept gaining more and more followers. Indeed, as I recall from following a blog in researchgate involving the author, Johan Prins, of the book, "The Physics Delusion": The urgent need to reinterpret modern physics", he claimed exactly that, but the person he was debating with (another quantum physicist) said that this view is not in keeping with mainstream quantum physics (e.g., as per Bohr).

 

However, he argued, as I recall, that this meant that entanglement was not nonlocal.

 

 

Edited June 16, 2016 by disarray

[Strange]

From what I gather, the idea that an 1) electron's field can span great distances and that 2) that two entangled particles become a single particle until observed is a fairly recent concept gaining more and more followers.

 

 

I'm pretty sure that neither of these are new concepts.

 

The fact that electric fields are infinite in extent is a classical concept - after all it follows an inverse square law and therefore the field extends forever.

 

Similarly, my understanding is that entangled particles have always been described by a single wave function. That is what entangled mean. (But I'm sure one of the experts will correct me if I am wrong.)

 

 

However, he argued, as I recall, that this meant that entanglement was not nonlocal.

 

Indeed. And that was part of Einstein's objection to it.

[disarray]

well yes, I understand the inverse square law, but in most cases, once two things are at a certain distance from each other, the effects are, for all practical purposes, negligent, (e.g., would we have to remove the moon very far from the earth before it just went its merry way?).

 

But yes, I see that entanglement provides a special case, though I don't know if anyone has a clear idea about just what is going on when they are entangled...kind of sounds like it might look those charts on mitosis....but I jest.

Edited June 17, 2016 by disarray

[Strange]

But we aren't talking about "practical purposes".

[swansont]

I'm not sure how that comment applies to my understanding of what a theory is.

 

 

"Just a theory" implies that one does not acknowledge that theory is the pinnacle of the scientific hierarchy.

Strange: You write that "This entangled "thing" can be spread over half the universe, but that's OK because quantum effects are inherently non-local anyway (in time and space)."

 

From what I gather, the idea that an 1) electron's field can span great distances and that 2) that two entangled particles become a single particle until observed is a fairly recent concept gaining more and more followers. Indeed, as I recall from following a blog in researchgate involving the author, Johan Prins, of the book, "The Physics Delusion": The urgent need to reinterpret modern physics", he claimed exactly that, but the person he was debating with (another quantum physicist) said that this view is not in keeping with mainstream quantum physics (e.g., as per Bohr).

 

However, he argued, as I recall, that this meant that entanglement was not nonlocal.

 

 

 

Since Prins is apparently challenging mainstream physics, I find it odd that he would be arguing for the current view on entanglement; especially in light of your recollection that he was arguing the opposite regarding locality. His book has Einstein's "God does not play dice" quote on it.

[michel123456]

 

 

Classically, a particle can't be at different points at the same time, so this is all moot, isn't it? We're discussing relativity here. Even under Einstein's relativity (i.e. finite c), a particle does not occupy more than one point at a time. So I'm still not seeing how you are getting this — you seem to be assuming the answer, rather than concluding it from other principles.

But if one consider that velocity has no limit that becomes untrue. For infinite velocity, a particle can be at 2 places at the same moment.

[TakenItSeriously]

But if one consider that velocity has no limit that becomes untrue. For infinite velocity, a particle can be at 2 places at the same moment.

Nice! This is a good explanation for why their must be a theoretical maximum on speed.

 

Edit to add:

Upon reflection, while it does sound like a paradoxical result, I'm not certain that it actually leads to a paradox.

 

The dual existence could only last for an instant in time like teleportation. One could imagine teleportation without creating paradox. For instance it doesn't violate cause and effect.

Edited June 17, 2016 by TakenItSeriously

[swansont]

But if one consider that velocity has no limit that becomes untrue. For infinite velocity, a particle can be at 2 places at the same moment.

You need to explain how infinite speed light propagation allows this, rather than just repeating it.

[michel123456]

You need to explain how infinite speed light propagation allows this, rather than just repeating it.

Infinite speed. Not especially infinite speed light propagation.

 

I thought it was trivial

 

for v=infinite you have δt=0, the interval of time between 2 positions is null.

Edited June 20, 2016 by michel123456

[swansont]

Infinite speed. Not especially infinite speed light propagation.

 

I thought it was trivial

 

for v=infinite you have δt=0, the interval of time between 2 positions is null.

 

 

I was talking about light speed, and AFAICT, so was everyone else.

[michel123456]

 

 

I was talking about light speed, and AFAICT, so was everyone else.

That is because light speed is a maximum.

The question was why is there a maximum at all. I tried to answer that question.

After answering that question, one could raise the question why does this maximum correspond to light speed.

[swansont]

That is because light speed is a maximum.

The question was why is there a maximum at all. I tried to answer that question.

After answering that question, one could raise the question why does this maximum correspond to light speed.

 

 

Light can travel at whatever speed is possible without having an infinite amount of energy. Massive particles can't. Thus, they are constrained to values below the maximum.

[michel123456]

My understanding is that SOL is the maximum speed at which information can be received. This interpretation makes SOL both a maximum and a relative.

 

 

 

Light can travel at whatever speed is possible without having an infinite amount of energy. Massive particles can't. Thus, they are constrained to values below the maximum.

What did you wrote there? I am afraid this might be misunderstood.

[swansont]

My understanding is that SOL is the maximum speed at which information can be received. This interpretation makes SOL both a maximum and a relative.

 

What did you wrote there? I am afraid this might be misunderstood.

 

 

We're talking about SOL having different values. Whatever that is, it's the limit. But whatever that value is, the energy of the light is finite. Not so with massive particles. Thus, massive particles will never travel at that speed.

[michel123456]

 

 

We're talking about SOL having different values. Whatever that is, it's the limit. But whatever that value is, the energy of the light is finite. Not so with massive particles. Thus, massive particles will never travel at that speed.

I understand nothing.

SOL has a single value depending on the medium. For void, SOL is c. For light, it is not only a maximum, it is also a minimum: it is The speed, there is no other. It is a constant.

A massive particle has not the same requirement to travel at a specific speed. A massive particle can travel at any speed it pleases. In fact it depends solely on the relative velocities with the different observers. If there are 100 observers traveling at 100 different velocities, each one of them will observe the same particle traveling at a different speed.

Now, Einstein tells us that if the particle is massless (a photon), the 100 observers will all measure the same particle traveling at the same speed. That is because for the 100 observers, time & space will change differently and give the same result to each observer.

My understanding of this is that in fact, the time-space transformation is an observational phenomenon

Edited June 22, 2016 by michel123456

[swansont]

I understand nothing.

SOL has a single value depending on the medium. For void, SOL is c. For light, it is not only a maximum, it is also a minimum: it is The speed, there is no other. It is a constant.

A massive particle has not the same requirement to travel at a specific speed. A massive particle can travel at any speed it pleases. In fact it depends solely on the relative velocities with the different observers. If there are 100 observers traveling at 100 different velocities, each one of them will observe the same particle traveling at a different speed.

Now, Einstein tells us that if the particle is massless (a photon), the 100 observers will all measure the same particle traveling at the same speed. That is because for the 100 observers, time & space will change differently and give the same result to each observer.

My understanding of this is that in fact, the time-space transformation is an observational phenomenon

 

 

And the photon's energy is not dependent upon the speed. That's the point. No matter your frame, the photon's energy will be finite. Not so for a massive particle that was hypothetically traveling as fast as a photon. Its energy would be infinite. Thus, it can't travel that fast, and we don't have to worry about it being in two places at once. It can't travel at a speed where that would be an issue. Your objection is not valid.

[disarray]

Swansont: Don't mean to be contentious or uppity (I'm sure you know a thousand times more about physics than I do), but I thought I read that a photon always travelled at c (never more nor less), but just seemed to go slower through a medium, e.g., a sheet of plastic, because it had to bounce around while in the plastic, but nevertheless was still bouncing at c.

 

Also, do you agree that time-transformation (as Michel says) and thus time dilation are observational and thus in the eye of the 100 beholders mentioned in the anecdote above.

How can it be "observational" if even atomic (and perhaps photon??) clocks slow down under certain conditions (e.g., not only with reference to an inertial observer, but also within a gravitational field, when accelerating, or whatever?). And indeed, do we take the twin paradox literally....If I put a banana in an extremely fast centrifuge, is it going to spoil and develop spots more quickly after an hour of twirling around than the one I leave outside the centrifuge?

 

As for space curvature...If we only take space curvature in a metaphorical abstruse sense (i.e., as einstein apparently admitted, we can't visualize space curvature and it is only an 'expression' after all to talk about what the math tells us), why do we take it in a literal sense when we talk about light curving as it passes the sun owning to spacetime curvature?

 

Seems to be a some confusing misnomers in advanced physics...If "time" is just a fourth dimension of space (e.g., owing, I am guessing, to the expansion of the universe at around the speed of c),then why don't we use a different term that sound more like it refers to space, since even time in the popular sense is measured by the (comparative) movement of things (such as the hands on a clock) through space

Edited June 26, 2016 by disarray

[Mordred]

You seem to have the wrong notion of time dilation. Time dilation isnt merely some mechanical clock slow down. It doesnt matter what type of clock you use and has nothing to do with the particles or components that make up the clock.

 

For example the Earth surfaces is bombarded with muons. Those muons have too short a mean lifetime to be able to reach the Earths surface. The only possible way they can do so is time dilation which has nothing to do with how we measure it.

 

It is something that will occur regardless if there is an observer or not.

This is one example of the reality of time dilation.

Another aspect is measurable gravitational redshift.

 

The twin paradox itself is an artifact of the coordinate system used in the paradox. It is solvable using a different coordinate system. The age of both twins are effected. The solution is in this article which details numerous poorly misunderstandings in GR due to various coordinate system artifacts.

http://www.blau.itp.unibe.ch/newlecturesGR.pdf "Lecture Notes on General Relativity" Matthias Blau

 

Curvature as mentioned is measurable. We even have a satellite doing just that near Earth.

 

https://en.m.wikipedia.org/wiki/Gravity_Probe_B

 

https://en.m.wikipedia.org/wiki/Time_dilation_of_moving_particles

 

The last link details several experiments on how time dilation affects the mean lifetimes of particles

Edited June 26, 2016 by Mordred

[disarray]

Mordred: Thanks. Will wade through your links.

For now, I would just mention that I was under the impression that clocks actually slowed down, e.g. planes taking a clocks around the world to show Einstein's time dilation effect, and the results showing a tiny difference in what the clocks said.

 

The key problem I have with relativity is the notion of time slowing down:

 

Does time really slow down for the muons entering the atmosphere, or does the curvature of spacetime cause them to age more quickly, much like the skin of a person who stays out in the sun too long will age more quickly. In short, is there any way that time dilation can be seen as a physical process?

[swansont]

Swansont: Don't mean to be contentious or uppity (I'm sure you know a thousand times more about physics than I do), but I thought I read that a photon always travelled at c (never more nor less), but just seemed to go slower through a medium, e.g., a sheet of plastic, because it had to bounce around while in the plastic, but nevertheless was still bouncing at c.

That's true and has nothing to do with what's being discussed.

 

Also, do you agree that time-transformation (as Michel says) and thus time dilation are observational and thus in the eye of the 100 beholders mentioned in the anecdote above.

How can it be "observational" if even atomic (and perhaps photon??) clocks slow down under certain conditions (e.g., not only with reference to an inertial observer, but also within a gravitational field, when accelerating, or whatever?).

Time is relative to the observer's frame, which is why 100 different observers can get 100 different answers.

 

And indeed, do we take the twin paradox literally....If I put a banana in an extremely fast centrifuge, is it going to spoil and develop spots more quickly after an hour of twirling around than the one I leave outside the centrifuge?

No, because time in the centrifuge's moving frame will run slower. It will take more time to do so. Unfortunately, to have an effect measurable in that way would require a speed large enough that the banana would be squished.

 

 

As for space curvature...If we only take space curvature in a metaphorical abstruse sense (i.e., as einstein apparently admitted, we can't visualize space curvature and it is only an 'expression' after all to talk about what the math tells us), why do we take it in a literal sense when we talk about light curving as it passes the sun owning to spacetime curvature?

 

Seems to be a some confusing misnomers in advanced physics...If "time" is just a fourth dimension of space (e.g., owing, I am guessing, to the expansion of the universe at around the speed of c),then why don't we use a different term that sound more like it refers to space, since even time in the popular sense is measured by the (comparative) movement of things (such as the hands on a clock) through space

We came up with the notion of time long before we realized the relationship with space. That dictates the terminology.

Mordred: Thanks. Will wade through your links.

For now, I would just mention that I was under the impression that clocks actually slowed down, e.g. planes taking a clocks around the world to show Einstein's time dilation effect, and the results showing a tiny difference in what the clocks said.

 

The key problem I have with relativity is the notion of time slowing down:

 

Does time really slow down for the muons entering the atmosphere, or does the curvature of spacetime cause them to age more quickly, much like the skin of a person who stays out in the sun too long will age more quickly. In short, is there any way that time dilation can be seen as a physical process?

Clocks on a plane slow down because time on that plane slowed down, and clocks measure time.

 

Fast-moving muons don't age more quickly. They age more slowly.

[disarray]

Swansont: Sorry, I meant fast-moving muons age more slowly. But again, do they age more slowly because of some physical reason other than time slowing down? (I can't get over thinking of time as an abstraction...so am looking for some other explanation.) And of course, how could one say that it is an observational thing...I presume the muons would age more slowly even though no one is observing them.

(Thanks for taking a moment to answer questions).

[swansont]

Swansont: Sorry, I meant fast-moving muons age more slowly. But again, do they age more slowly because of some physical reason other than time slowing down? (I can't get over thinking of time as an abstraction...so am looking for some other explanation.)

 

Time slowing down is the best fit to our understanding. There's no evidence that it's any kind of interaction.

 

And of course, how could one say that it is an observational thing...I presume the muons would age more slowly even though no one is observing them.

One can say almost anything if one's understanding is incomplete.