Why we can never travel faster than the speed of light

[sjastro]

I'll maybe try something a little bit simpler, and that I can more easily get.

You are traveling along at 87% of c, time dilation is affected by a multiplying factor of two, etc. So, does the length contraction affect for the thing in motion (you) also become affected by a factor of two? Or is it directly proportional and equal always to time dilation?

Or are there other factors I'm unaware of right now/not considering that would increase length contraction slightly in order to make c the same always for all observers in their own frames of reference?

Or what am I missing here, etc?

Because both being affected by a factor of two is only 75%, correct? Not 87% IOW's, etc.

Much thanks.

Take Care/God Bless.

If you are travelling at 87% the speed of light you will observe length contraction such as the distance in the direction you have travelled by a factor 1/γ = 1/2.
Your clock will not slow down in your frame of reference, only a observer at rest relative to you will measure your clock as having slowed down or dilated by a factor γ =2.

 

[Neogaia777]

If you are travelling at 87% the speed of light you will observe length contraction such as the distance in the direction you have travelled by a factor 1/γ = 1/2.
Your clock will not slow down in your frame of reference, only a observer at rest relative to you will measure your clock as having slowed down or dilated by a factor γ =2.

I get that so far, but that's not what I was trying to address?

If time dilation is affected by a factor of two, and so is length contraction, then that's 75% of let's say "100", right? and that leaves 25, right? but shouldn't it be 13?

Maybe I need to think some more about this? I can't seem to properly get across what I'm trying to be asking right now, etc.

I maybe need to take it back to the drawing board maybe, so just nevermind for now, ok.

But thanks anyway.

Take Care/God Bless.

 

[SelfSim]

... The reality is if you want to understand SR you need to understand the mathematics.

... and that's a whole different truth compared with the truth currently being confronted by @Neogaia777, eh?

PS: Aka intuition just doesn't cover the ground necessary in order to gain the understanding.

 

[sjastro]

... and that's a whole different truth compared with the truth currently being confronted by @Neogaia777, eh?

PS: Aka intuition just doesn't cover the ground necessary in order to gain the understanding.

In an earlier post I quoted the Lorentz transformations without deriving them, I left it as an exercise for DeepSeek.
Its derivation took pages and pages and pages.................... no human would have gone down this line, it made a number of mistakes which it recognized and corrected before coming to the correct derivation.

The derivation of Lorentz transformation is textbook stuff, it could have accessed the information during its learning process instead it reinvented the wheel in the process.

Here is the long tortuous process it took to come up with the correct answer.

 

[sjastro]

I get that so far, but that's not what I was trying to address?

If time dilation is affected by a factor of two, and so is length contraction, then that's 75% of let's say "100", right? and that leaves 25, right? but shouldn't it be 13?

Maybe I need to think some more about this? I can't seem to properly get across what I'm trying to be asking right now, etc.

I maybe need to take it back to the drawing board maybe, so just nevermind for now, ok.

But thanks anyway.

Take Care/God Bless.

If time dilation is affected by the factor γ = 2, then the factor for length contraction is 1/γ =1/2.
I have no idea what the rest of your post is about.

 

[SelfSim]

In an earlier post I quoted the Lorentz transformations without deriving them, I left it as an exercise for DeepSeek.
Its derivation took pages and pages and pages.................... no human would have gone down this line, it made a number of mistakes which it recognized and corrected before coming to the correct derivation.

The derivation of Lorentz transformation is textbook stuff, it could have accessed the information during its learning process instead it reinvented the wheel in the process.

Here is the long tortuous process it took to come up with the correct answer.

View attachment 360625​

I'm blown away by its problem solving capabilities there!
I mean .. it makes suggestions and then pursues them to an end result .. even if it ends up being a dead end and then says: 'Let me think!' .. followed by yet another suggestion, (etc) ..!
That's amazing .. (and slightly scary!)

 

[SelfSim]

If time dilation is affected by the factor γ = 2, then the factor for length contraction is 1/γ =1/2.
I have no idea what the rest of your post is about.

To self: 'thank goodness its not just me'! ..

 

[sjastro]

To self: 'thank goodness its not just me'! ..

DeepSeek couldn't make heads or tails of it either.

 

[Neogaia777]

I'm going to work on learning more, and acquiring more knowledge (which will take time), I just maybe figured you guys might have been getting kind of bored with the more quote/unquote "normal" believers or religious folks/types you're most usually used to dealing with most of the time on here maybe, etc.

But and/or anyway, have fun with them, ok. I'll be back at some point, but it will/might take a little bit of time. Unfortunately, I can't learn quite as fast as AI, etc. I still have to eat, sleep, shower, shave, take care of the things I need to take care of, pay attention to my cats, that sort of thing, etc, and AI doesn't have to do any of these things, etc.

Take Care/God Bless.

 

[Neogaia777]

I'm going to work on learning more, and acquiring more knowledge (which will take time), I just maybe figured you guys might have been getting kind of bored with the more quote/unquote "normal" believers or religious folks/types you're most usually used to dealing with most of the time on here maybe, etc.

But and/or anyway, have fun with them, ok. I'll be back at some point, but it will/might take a little bit of time. Unfortunately, I can't learn quite as fast as AI, etc. I still have to eat, sleep, take care of the things I need to take care of, pay attention to my cats, that sort of thing, etc, and AI doesn't have to do any of these things, etc.

Take Care/God Bless.

The idea will probably be just simply solved/resolved with a little more learning, I was just trying to think outside of the normal usual box for a minute, and maybe let you guys in on how I was currently thinking, but I'm pretty sure it will be resolved with a little more learning, etc. I do this kind of thing all of the time, and it's kind of a part of the process of how I try to reason things out/think, and it certainly wouldn't be the first time, and probably most definitely won't be the last, that it is just put on the back burner until later when most of them are most usually solved or resolved with a little more knowledge, or learning, or thinking, that happens over time, etc.

Anyway, have fun with the other guys you most usally run into/know/already always know, on here, or can already read/predict/know like a book most of the time always on here, ok. I know I get bored with it sometimes, which is why I also like to come on here and try to engage with people more like you guys sometimes, etc.

But I'll come back another time, and probably after I know a little bit more preferably, ok.

Take Care/God Bless/Later.

 

[Mark Quayle]

I'm not sure about this, but I get the sense that you may be trying to visualise spacetime like what many around here call a 'physical', or a 'material' object? If so, it very clearly isn't either of those.

Its a model (which differs from a tangible material thing) and it has changed over time. @sjastro has pointed out, it has changed 3 times: '(i) classical physics space, (ii) spacetime in the form of a vacuum is a quantum field in the lowest energy state from which virtual particles pop into and out of existence which has been indirectly observed in laboratory experiments' and (iii) Dark energy was included as a parameter of GR's spacetime in order to account for the observed the expansion (acceleration) of the universe.

I'm unclear on whether that may help a little(?) I'm just trying to assist with the visualisation here .. (its not easy to bridge the conceptual gap).

Thanks. I'm at least encouraged by the "model" thing. The way they (science magazines) talk, that 'model' is what is moving(?) the distant galaxies away from us. But since you say it is only a mental model, and not a force or medium or any material thing, then, I have to conclude, it is only a mental crutch to help us think about how those galaxies have gone(?) so far so fast, or at least why they are (or were, some billions of years ago) receding away from us so fast. The fact is, they definitely are receding that fast, and the measurement is consistent in spite of 'grid expansion'. It's not double-talk, it's just that we have to think of it that way.

So, since we don't know what is beyond our sight, it's useless to guess at a static center of the universe. I'm wondering if, from any particular point in distant space, the universe would appear to have that for the center point, everything at the outer edges of visibility a circular globe 14 billion light years away.

I have heard an authority (don't remember who) on this subject, or maybe it was on quantum theory, say that anyone who thinks they understand it doesn't.

Beats me.

 

[Hans Blaster]

Thanks. I'm at least encouraged by the "model" thing. The way they (science magazines) talk, that 'model' is what is moving(?) the distant galaxies away from us. But since you say it is only a mental model, and not a force or medium or any material thing, then, I have to conclude, it is only a mental crutch to help us think about how those galaxies have gone(?) so far so fast, or at least why they are (or were, some billions of years ago) receding away from us so fast. The fact is, they definitely are receding that fast, and the measurement is consistent in spite of 'grid expansion'. It's not double-talk, it's just that we have to think of it that way.

The galaxies are moving because space is expanding. The model is just the device used to understand it.

So, since we don't know what is beyond our sight, it's useless to guess at a static center of the universe. I'm wondering if, from any particular point in distant space, the universe would appear to have that for the center point, everything at the outer edges of visibility a circular globe 14 billion light years away.

The Universe is not static, it is expanding. Nor does it have "center". From all points in the universe it appears to be expanding away in all directions. The visible horizon (the furthest that can be seen) is much further than 14 billion ly away due to expansion.

I have heard an authority (don't remember who) on this subject, or maybe it was on quantum theory, say that anyone who thinks they understand it doesn't.

Beats me.

 

[sjastro]

I'm blown away by its problem solving capabilities there!
I mean .. it makes suggestions and then pursues them to an end result .. even if it ends up being a dead end and then says: 'Let me think!' .. followed by yet another suggestion, (etc) ..!
That's amazing .. (and slightly scary!)

While it came up with a very messy derivation of the Lorentz transformation I asked it a far more challenging question.

In dark energy modeling derive the K-essence energy density: ρₖ = [2XK’(X) – K(X)] + V(ψ).

First the preliminaries in layman terms, dark energy causes the expansion of the universe to accelerate and one model to explain dark energy is quintessence which posits the existence of a dynamic scalar field. This scalar field is a changing energy field like an invisible fluid that permeates space and evolves with time.
The quintessence field is like a ball rolling down a hill where the shape of the hill, the potential V(ψ), controls how the ball moves and depending on how fast or slow it moves the energy changes, which determines how fast the universe expands.
Potential energy is converted into kinetic energy which determines the speed at which the ball moves or universe expands.

However the universe can accelerate or slow down without being dependant on the potential energy, the kinetic energy can change alone which is known as K-essence.

Here is DeepSeek's derivation of the equation which is remarkable, it asks questions, and answers them which leads to the derivation.

 

[SelfSim]

While it came up with a very messy derivation of the Lorentz transformation I asked it a far more challenging question.


First the preliminaries in layman terms, dark energy causes the expansion of the universe to accelerate and one model to explain dark energy is quintessence which posits the existence of a dynamic scalar field. This scalar field is a changing energy field like an invisible fluid that permeates space and evolves with time.
The quintessence field is like a ball rolling down a hill where the shape of the hill, the potential V(ψ), controls how the ball moves and depending on how fast or slow it moves the energy changes, which determines how fast the universe expands.
Potential energy is converted into kinetic energy which determines the speed at which the ball moves or universe expands.

However the universe can accelerate or slow down without being dependant on the potential energy, the kinetic energy can change alone which is known as K-essence.

Here is DeepSeek's derivation of the equation which is remarkable, it asks questions, and answers them which leads to the derivation.

View attachment 360652​

.. goodness me! Simply amazingly stunning!

What kind of learning approach is that?

Whatever its called, the above example demonstrates its problem solving capabilities in action!

We can actually see how its thinking there!

PS: I notice the Australian Federal government has banned this AI from being installed on their official mobile phones, eh? (I saw this in the news, just today).

 

[sjastro]

.. goodness me! Simply amazingly stunning!

What kind of learning approach is that?

Whatever its called, the above example demonstrates its problem solving capabilities in action!

We can actually see how its thinking there!

Its training involves reinforcement learning but the exact details are a trade secret and it tows the party line.

​

When it came to criticizing my layman explanation of K-essence it had no such reservations.

​

This highlights the pitfalls of giving a simplified explanation of a complex subject given accuracy can be compromised.

​

PS: I notice the Australian Federal government has banned this AI from being installed on their official mobile phones, eh? (I saw this in the news, just today).

I saw this on the news recently, I doubt having been a forensic scientist in the field of forensic engineering in the automotive industry will make China a greater superpower, the Americans probably know more about me through GPT-4o and Google.

I did however ask DeepSeek a loaded question having known the answer beforehand whether it can be run on a GPU with a sufficiently high VRAM.
Here it can be run as a standalone utility if one is worried about personal information being spread around the internet.

It again gave the standard party line response.

OpenAI on the other hand had no such reservations.