Twin paradox (split)

[Mordred]

24 minutes ago, Abouzar Bahari said:

For us it is a real physical change orelse the relativity is useless completely. However, we use it in our satellites, airplanes, or others today. Please do not scape from the reality. The ZPF (vacuum/ Ether) is the absolute frame. 

 

there is no absolute frame of reference that in itself is not supported by mainstream physics hence one of the reasons why this is in speculation and not mainstream physics. An absolute frame doesn't even exist in any quantum treatment with regards to decays and aging. Those formulas you claimed do not matter in fact show the above quotation as false.

 

Edited September 7 by Mordred

[exchemist]

1 hour ago, Abouzar Bahari said:

Yes, true. In our frame (stationary frame (S)), the muons' life is extended. That is, we say, a real physical change. Hence, the clock of a high-speed rocket is really dilated, as in the Hafele-Kitting experiment for an airplane. However, the clock on the earth is not dilated for the S' observer on the rocket (contrary to what SR says). 

 

This  does not make sense. Your rocket is analogous to the muons. The clock in the rocket will only show time dilation to observers on the ground, not to those aboard the rocket. Observers on the rocket will see clocks ticking at the normal rate. So it makes no sense to say time aboard the rocket is "really" dilated. There is no greater "reality" for observers on the ground than for observers aboard the rocket.

(Observers on the rocket will however see a shortening of the distance it has to travel, relative to objects at rest with respect to the Earth, just as with the muons.) 

I think you need to abandon this idea of one perspective being more "real" than another. It seems to me to be a fatal error to think in this way. 

 

Edited September 7 by exchemist

[Harrot]

On 9/7/2024 at 1:50 AM, swansont said:

No physical properties change, as such. They just don’t have the same value, since they are relative to the frame from which they are measured. The value is not intrinsic or absolute. A meter stick measured by an observer in relative motion has a length shorter than 1m. But nothing physical has happened to the meter stick. It does not physically shrink just because I observe it. Thus, no mechanism is necessary.

But the explanation of the relative measurement is well known: c is invariant 

To be more precise, the mathematical explanation is well known: C is invariant.

But it's not the physical explanation: the physical explanation answer the question "why is c invariant", and it's only when someone can explain why c is invariant that he can claim that something is physically shrinking or not. To do otherwise is mere speculation.

So what is the phenomenology that would enable us to transform this principle (c is invariant) into a physical necessity?

[swansont]

10 minutes ago, Harrot said:

To be more precise, the mathematical explanation is well known: C is invariant.

Lorentz transformations are mathematical, so yeah.

10 minutes ago, Harrot said:

But it's not the physical explanation: the physical explanation answer the question "why is c invariant", and it's only when someone can explain why c is invariant that he can claim that something is physically shrinking or not. To do otherwise is mere speculation.

So what is the phenomenology that would enable us to transform this principle (c is invariant) into a physical necessity?

I’m not sure what you mean by physical explanation; nothing about the meter stick physically changes, as I said, so there’s nothing “physical” to explain.

The contention was “SR does not explain why the physical properties of the moving bodies are transformed’
“why is c invariant?” is a different question. Physics is an attempt to try and explain/predict how nature behaves, not why it is the way it is. 

The claim that nothing is shrinking is based on c being invariant. The ramifications are predicted and experiments confirm it. That’s in the domain of physics. “Why” is in the domain of metaphysics.

[Markus Hanke]

3 hours ago, Harrot said:

But it's not the physical explanation: the physical explanation answer the question "why is c invariant"

If c wasn’t invariant, there’d be a plethora of unresolvable physical paradoxes, and the universe wouldn’t have evolved. An invariant c is a fundamental prerequisite for any internally self-consistent notion of spacetime and causality, among other things.

To put it differently, in the abstract space of all conceivable sets of laws of physics, only those with an invariant c can give rise to a macroscopic, self-consistent spacetime.

[Harrot]

7 hours ago, swansont said:

“why is c invariant?” is a different question. Physics is an attempt to try and explain/predict how nature behaves, not why it is the way it is. 

Okay, so your misunderstanding stems from the fact that you've never noticed that when we talk about a “why question” in physics, scientists are of course talking about a “how question”.

Why does heat flow from hot to cold?

Why is the density of water lower in its solid state than in its liquid state?

Why is the sun's corona so hot?

Why can an airplane fly?

Etc.

You see, these are all questions of why, and scientists don't react in this way: “There's the word ‘why’, it's once again a metaphysical question and physics doesn't deal with it”.

That would be a poor excuse to hide the fact that we don't know the answer, don't you think?

Now that we know that the question “why is c invariant” is a scientific question, not a metaphysical one, does anyone have a hypothesis to explain this fact?

 

5 hours ago, Markus Hanke said:

If c wasn’t invariant, there’d be a plethora of unresolvable physical paradoxes, and the universe wouldn’t have evolved. An invariant c is a fundamental prerequisite for any internally self-consistent notion of spacetime and causality, among other things.

Probably, but the question isn't “what would happen if c wasn't invariant”, but “why is c invariant”, and I'll translate it for you into a clearer sentence.

Old version: “How does nature make c invariant?"

Modern variant: “What's the phenomenology behind it?" As with heat flow, ice density, the way an airplane can fly, electrical charges, etc., for which we now know there's something going on behind the curtain that we can describe further.

Because if you were to stick to the other way of looking at things, to the question: “Why is water less dense in its solid state?”, you'd have the same answer: “there would be a plethora of unsolvable physical paradoxes, and the universe wouldn't have evolved” and I'm sure you understand that this isn't the right way to do physics. Of course, if you assert something that isn't observed, it would make the world incoherent soon or later, but this reasoning says nothing about the phenomena we do indeed observe.

It would be simpler to say, “That's because things are the way they are” and that was the answer before the invention of the scientific method, but I don't think it's very useful when we want to use the force of nature, like for space travel and so on.

 

 

 

 

[Genady]

25 minutes ago, Harrot said:

“why is c invariant”

Because space and time rotate into each other without stretching. For c not to be invariant, they would need to rotate AND stretch.

[swansont]

25 minutes ago, Harrot said:

Okay, so your misunderstanding stems from the fact that you've never noticed that when we talk about a “why question” in physics, scientists are of course talking about a “how question”.

Why does heat flow from hot to cold?

Why is the density of water lower in its solid state than in its liquid state?

Why is the sun's corona so hot?

Why can an airplane fly?

Etc.

You see, these are all questions of why, and scientists don't react in this way: “There's the word ‘why’, it's once again a metaphysical question and physics doesn't deal with it”.

I was careful not to say that physics doesn’t answer why questions, so this is moot.

 

[Mordred]

Why c is invariant is one of those questions that has no answer. We know that c is invariant. That has been confirmed to extremely high precision but the closest answer afiak is that

All massless (uncoupled) particles travel at c and this is reflected in the permittivity and permeability relation of the vacuum.

\[c^2=\frac{1}{\mu_0\epsilon_0}\]

So one could argue it is due to the permittivity and permeability of the vacuum along with the nature of an observers lightcone.

Edit just noticed the person I was replying to is now banned.

Edited October 9 by Mordred