Relativity?

How does science work? And what's all this about quantum mechanics?

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Walker
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Re: Relativity?

Post by Walker »

ken wrote: Fri Oct 13, 2017 6:50 am...
Are you actually serious?
ken
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Re: Relativity?

Post by ken »

uwot wrote: Fri Oct 13, 2017 7:47 am
ken wrote: Fri Oct 13, 2017 4:17 amWhat role does photon play in making things happen.
This from wikipedia: "It turns out that all interactions which affect matter particles are due to an exchange of force carrier particles..." https://en.wikipedia.org/wiki/Exchange_force
Photon exchange is the basis for all chemical reactions. They in turn are responsible for every metabolic event that happens to you, and it is those events that determine the ageing process. At the speed of light, there can be no photon exchange, because it would require photons to exceed the speed of light. So: No photon exchange. No metabolic events. No ageing. The same is true for brain states; if you accept that the brain has at least some role in consciousness, then your consciousness is also affected, and very possibly stops altogether; which would be my guess.
This may be a ridiculous clarifying question but what do you mean by "At the speed of light, there can be no photon exchange?" Do you think photons only travel one way in the whole entire Universe?

To Me, it would not matter if at rest or travelling at the speed of light or any thing in between, photons are travelling in all directions. So, it would not matter at all if travelling at the speed of light there will obviously be light coming from the opposite and from all other directions also, at the speed of light too. There will be photon exchange no matter what because light photons travel in ALL directions. This is because there is a light source in ALL directions in the Universe. Therefore , there will be a metabolic event that happens always that will cause the ageing process, no matter if traveling at the speed of light or at rest, or anywhere in between.
uwot wrote: Fri Oct 13, 2017 7:47 am
ken wrote: Fri Oct 13, 2017 4:17 amWhat do you mean for the atoms nothing happens?

The atoms are still travelling between objects at the speed of light, so that is what is happening, is this wrong?
Fair enough. The atoms get from one place to another, but the types of interactions, the exchange of photons, for example, that take place between atoms at sub-light speed, simply cannot happen; if light speed really is the limit.
I do not know what you are trying to get at here?
uwot wrote: Fri Oct 13, 2017 7:47 am
ken wrote: Fri Oct 13, 2017 4:17 amI agree wholeheartedly that WHILE a human body was travelling at the speed of light, if they could, then for that person there MIGHT a perception outside of the body that no time was passing. But, to Me, from when that human body was last at rest, before travelling at the speed of light, if it could, up to when it was at rest again, after travelling at the speed of light, if it did, then the days or years that that body took to travel the distance that it did, at the speed of light, then that is how much that body would have aged by.
What experiments like Hafele-Keating, and relativistic muon decay (more wiki for you: https://en.wikipedia.org/wiki/Time_dila ... _particles ) is that speed does affect the rate at which things happen.
What actual evidence is there for this? The supposed evidence I have seen does not add up.
uwot wrote: Fri Oct 13, 2017 7:47 am So, weird as it is, the ageing of your body is determined by what happens to it, rather that the number of times the Earth goes round the Sun.
So, if the ageing of the body is determined by what happens to it, then what is the actually difference that happens to the body if it is at rest compared to when it is travelling at the speed of light?

To Me, photon exchange still happens and according to you photon exchange is the basis for all chemical reactions.
uwot wrote: Fri Oct 13, 2017 7:47 am
ken wrote: Fri Oct 13, 2017 4:17 amAnd, if for example that body was in front of a mirror when they were travelling, then for that person they would see a normal rate of change. If this is not correct, then why not?
Assuming that consciousness is a function of brain processes, they wouldn't see anything, because their brain would have stopped functioning.
Are you capable of imagining IF a human being with a functioning brain was traveling at the speed of light and looking at them self in mirror? IF you are capable of that, then what would be happening? Would that human body continue to age, or would it just stop ageing but continue to live, or would it just stop ageing and also stop breathing and stop pumping blood?
ken
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Re: Relativity?

Post by ken »

surreptitious57 wrote: Fri Oct 13, 2017 7:56 am
ken wrote:
surreptitious57 wrote:

Because nothing travelling at the speed of light can experience time
Do you know a human being who has travelled at this speed and asked them to clarify for you
No but then why would I need a human being to tell me that time cannot be experienced when travelling at that speed
Are there not other ways knowledge can be acquired rather than from personal experience which is not always reliable
What other ways besides from personal experience can knowledge be acquired?
ken
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Re: Relativity?

Post by ken »

surreptitious57 wrote: Fri Oct 13, 2017 8:05 am
ken wrote:
if it takes a human being or a photon let us say 8 and half minutes to travel from the sun to the earth at the speed
of light to you it took no time at all but to most other human beings they would say it took 8 and half minutes
Were I travelling at the speed of light then it would take no time at all
And were I a stationary observer it would take eight and a half minutes
Although it MIGHT APPEAR to have taken no time for an observer travelling at the speed of light to travel that distance, to YOU how much time did it take?

You do KNOW the difference between what APPEARS to have happened and what ACTUALLY did happen, right?
ken
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Re: Relativity?

Post by ken »

Walker wrote: Fri Oct 13, 2017 10:54 am
ken wrote: Fri Oct 13, 2017 6:50 am...
Are you actually serious?
Were you meant to quote some thing that I said here?

Or, are you asking if I am actually serious about every thing that I write?
thedoc
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Re: Relativity?

Post by thedoc »

Walker wrote: Fri Oct 13, 2017 4:57 am
thedoc wrote: Fri Oct 13, 2017 3:42 am Or it could already be on it's way to becoming a train wreck like the evolution thread, just waiting for some creationist to chime in with "It's only a theory".
Have you ever heard the Dzogchen anecdote about distraction?
Not by that name, but the concepts were familiar.
thedoc
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Re: Relativity?

Post by thedoc »

What did I say? less than 2 days and the relativity deniers are coming out of the woodwork.
thedoc
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Re: Relativity?

Post by thedoc »

ken wrote: Fri Oct 13, 2017 1:34 pm
What other ways besides from personal experience can knowledge be acquired?
If you listen to other people, you don't have to make the same mistakes to learn not to do it. It's called learning form others.

You can look at the evidence and figure out why things are the way they are. Astronomy and Paleontology do this all the time.

You can learn from what others have discovered in the past, there is a popular phrase, "I can see far because I have stood on the shoulders of giants.

I don't have access to a large telescope or a particle accelerator or go on dinosaur digs, but I can read the reports of those who have this equipment or have done that.
davidm
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Re: Relativity?

Post by davidm »

ken wrote: Fri Oct 13, 2017 1:38 pm
surreptitious57 wrote: Fri Oct 13, 2017 8:05 am
ken wrote:
if it takes a human being or a photon let us say 8 and half minutes to travel from the sun to the earth at the speed
of light to you it took no time at all but to most other human beings they would say it took 8 and half minutes
Were I travelling at the speed of light then it would take no time at all
And were I a stationary observer it would take eight and a half minutes
Although it MIGHT APPEAR to have taken no time for an observer travelling at the speed of light to travel that distance, to YOU how much time did it take?

You do KNOW the difference between what APPEARS to have happened and what ACTUALLY did happen, right?
You seem to think there is some ABSOLUTE TRUE TIME independent of reference frames. There isn’t! That is the whole point.

To back up briefly, I think everyone should drop talk of “if a human (clock, dog, rocket ship, whatever…) could travel at the speed of light, what would it experience or how would it behave?” No object with mass can travel AT the speed of light. What can be discussed is what happens when an objects travels at relativistic velocities; i.e., ever closer to the speed of light.

Did you not look at this video?

In the moving reference frame, there is one tick of the light clock.

In the ground frame, there are three ticks of the light clock.

Now imagine that each tick of the clock represents ten years. This is true for both reference frames.

Imagine the two dudes above are twins. When the traveling twin leaves earth, he and his twin brother are 30 years old. Now he returns to earth and the twins compare their clocks.

Question: how old is each twin now?
thedoc
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Re: Relativity?

Post by thedoc »

davidm wrote: Fri Oct 13, 2017 4:52 pm
You seem to think there is some ABSOLUTE TRUE TIME independent of reference frames. There isn’t! That is the whole point.

To back up briefly, I think everyone should drop talk of “if a human (clock, dog, rocket ship, whatever…) could travel at the speed of light, what would it experience or how would it behave?” No object with mass can travel AT the speed of light. What can be discussed is what happens when an objects travels at relativistic velocities; i.e., ever closer to the speed of light.

Did you not look at this video?

In the moving reference frame, there is one tick of the light clock.

In the ground frame, there are three ticks of the light clock.

Now imagine that each tick of the clock represents ten years. This is true for both reference frames.

Imagine the two dudes above are twins. When the traveling twin leaves earth, he and his twin brother are 30 years old. Now he returns to earth and the twins compare their clocks.

Question: how old is each twin now?
This is a relatively simple math problem, the space traveling twin would be 40 years old and the Earth bound twin would be 60 years old.

Carl Sagan did something like this on the original Cosmos series, I didn't get to watch the new series with Neil deGrasse Tyson, the cartoon depictions of history put me off a bit.
Last edited by thedoc on Fri Oct 13, 2017 5:13 pm, edited 1 time in total.
davidm
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Re: Relativity?

Post by davidm »

BTW, that's a really quick video, just four seconds long, but if people view it again (or for the first time), ignore that clocks for a moment and pay attention to how the two stick figures are depicted. Notice the difference?
davidm
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Re: Relativity?

Post by davidm »

thedoc wrote: Fri Oct 13, 2017 5:08 pm
davidm wrote: Fri Oct 13, 2017 4:52 pm
You seem to think there is some ABSOLUTE TRUE TIME independent of reference frames. There isn’t! That is the whole point.

To back up briefly, I think everyone should drop talk of “if a human (clock, dog, rocket ship, whatever…) could travel at the speed of light, what would it experience or how would it behave?” No object with mass can travel AT the speed of light. What can be discussed is what happens when an objects travels at relativistic velocities; i.e., ever closer to the speed of light.

Did you not look at this video?

In the moving reference frame, there is one tick of the light clock.

In the ground frame, there are three ticks of the light clock.

Now imagine that each tick of the clock represents ten years. This is true for both reference frames.

Imagine the two dudes above are twins. When the traveling twin leaves earth, he and his twin brother are 30 years old. Now he returns to earth and the twins compare their clocks.

Question: how old is each twin now?
This is a relatively simple math problem, the space traveling twin would be 40 years old and the Earth bound twin would be 60 years old.
Correct. I don't think Ken is grokking this, though. :?
davidm
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Re: Relativity?

Post by davidm »

ken wrote: Fri Oct 13, 2017 1:28 pm
This may be a ridiculous clarifying question but what do you mean by "At the speed of light, there can be no photon exchange?"
Did you miss the part where he writes: ... because it would require photons to exceed the speed of light?
thedoc
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Re: Relativity?

Post by thedoc »

davidm wrote: Fri Oct 13, 2017 5:10 pm
Correct. I don't think Ken is grokking this, though. :?
How long has it been since you read about Valentine Michael Smith or Lazarus Long? I read them a long time ago and I remember reading about Lazarus Long, but I'm having a hard time remembering "Stranger in a Strange land".
davidm
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Re: Relativity?

Post by davidm »

I read Heinlein when I was a kid; I would also say he penned the best (and most accurate) time travel story ever written, "All You Zombies." I believe the full text can be found online.
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