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How might Dr.Feynman intuitively explain time dilation?
How might the great Dr.Feynman explain proper time dilation of a
macroscopic object during a (real) round trip where it lands on
a hypothetical planet orbiting Proxima Centauri (4LY) and then returns
to earth in the most intuitive (simple) way? I'm asking on behalf of
a contact.
Respectfully, do not answer using arguments like
"space-time rotation matrices", "twin paradox", and
the like unless if is flat-out intuitive. I can envision
how he might do this. If said explanation exists, please
include it. As best I can tell, he always had a beautiful
simple way of explaining things like this.
Koshka, thank you for your answer. I really like it.
The other parts of the universe did not allow Steve's
family to physically go into the future (much) in my thought
experiment. So, time really did advance at a slow rate for them,
and, theoretically they still could have accumulated real time knowledge
in their thermodynamic states. The same physics that applied to them
could have been applied to Steve. You see, the universe itself had decided
to change the rate at which time (and knowledge) advanced for the family.
There is really no paradox.
I think my current question is much more interesting, and the fact
that Scythain says, "That's never been done either.", really
gives me pause. Again, I'm considering a real time-like trip using
macroscopic objects.
I looks like Scythian scared off all takers ;)
Here is the answer to my themodynaimc-relativistic
coffee-bean paradox that didn't garner much interest
while I wait a little longer.
The answer to the question simply put is:
Steve any his family fall asleep as a result of
some ponderable futhuristic themodynaimc effects.
Let's call them cryonics. Steve is sent off (asleep)
on his relativitic trip. Latter the ENTIRE family
wakes up from their themodynaimic sleep, finishes
eating there breakfast, walks out the door, and
realizes 8 years have passed on earth. Or if Steve
had never entered into cryogenic sleep, there would
be some confusion between him and his family. No big
deal, the laws of physics are invaiant under coordinate
transformation we think.
Interesting mix of relativity and themodynaimics?
I'll let you decide, but I thought other's might have some
fun solving what I considered to be an engineering puzzle;
no FTL and no instantaneous starts and stops a
llowed!
I want some brave takers of my current question right now! ;)
This is really interesting, at least to me.
@koshka, I quote myself (above):
"theoretically they still could have accumulated real time knowledge
in their thermodynamic states" You see, words like sleeping, frozen,
etc. get us into trouble. I was trying to generalize.
They could have been aware of events mentally and even in an animate way and
still not "aged". I thinks it's more interesting to "awaken" in the future
without prior knowledge of events. Remember, I pointed out Steve
could (or not) have also take part in "cryonics" during his trip. Real time is the
only criteria events or not.
Hello my friend. Thank you for your interest in my other answer.
WE, cannot do any of this NOW so there
is nothing to AGREE or DISAGREE about. Yes? Think
future. This a thought experiment. Yes? The human
brain has not been proven to RETAIN knowledge must less
RECEIVE R.T.K using using current technology yet, YES?
In my T.E. "the family" remains in a closed system relative
to the rest of the universe, but information "MAY" still pass
in and out of said system. Yes, entropy of the universe will
indeed increase, and I'm now going to throw you another curve:
Consider ONE more (notice that word ONE) extreme version OF MY
T.E. There is another chunck of universe I will again call the family.
It is protected from heat death compliments of its dying external
universe; the family's "microstates and knowledge are somehow conserved".
Indeed, in this ONE T.E. the universe may expand and/or contract
many times, but, by some ponderable physical means, much knowledge
(not all) is held in trust by the family. In the future, if human
entities cannot handle this then silicon based entities, for example,
containing your mind, feelings, and accumulating knowledge might.
There is no right or wrong answer. Theoretically, the laws of
physics do not bar any of this. So ideas like past-present-future
have no meaning. This "machine" keeps repairing itself without
end. I hinted in the other question there are many many scenarios.
So barring crazy answers, there is no right or wrong answer.
If this goes on we'll have PDF files up the ying yang :)
4 個解答
- Scythian1950Lv 79 年前最愛解答
As far as I know, Richard Feynman never really had a "beautiful, simple" way of explaining the Twin Paradox. I don't know if anybody ever has, because that would be providing a "flat out intuitive" explanation of special relativity. That's never been done either. The mathematics may be elementary, but the mind-bending consequences of it defies both intuition and common sense.
I would LOVE to see others offer "elegant Richard Feynman" explanations of special relativity, time dilation, and the Twin Paradox. Go for it, people!
- DaveWHLv 79 年前
I have Richard Feyman's famous 'Lectures on Physics' texts, and I often found his explanations rather difficult to follow!!
I'll try and give you an explanation, but its not easy!. The whole theory of Special Relativity is based around one premise, that the velocity of light is the same in ALL reference frames. Why? Well, for that, you have to look at Maxwell's field equations [ indeed, Einstein had to make sure that Special Relativity did not contradict these equations!]. Within these equations, there is a constant term that crops up when you go through the process of deducing the wave nature of electromagnetic radiation [ a standard exercise for undergraduates]. The term is
1 / √ (μo εo)
Now, μo, the permeability of free space and εo, the permittivity of free space, are the same, as far as we know, all over the universe. This term IS the velocity of light, c. So, you can see that the velocity of light depends ONLY on these two constants. The velocity of light is the ONLY velocity that is NOT RELATIVE TO ANYTHING ELSE!!. It is governed only by these two constants. So, it doesn't matter what your frame of reference is, these two constants are the same. If you were in a spaceship travelling at 90% of the speed of light, these constants are the same INSIDE YOUR SHIP as outside. So the velocity of light MUST be the same inside and outside your ship. BUT, in order for it to be MEASURED as being the same, THE METER RULES AND CLOCKS YOU USE MUST CHANGE. Your meter rule MUST be shorter that those on earth and your clocks MUST run more slowly than those on earth otherwise you would measure a DIFFERENT VALUE OF c than that on earth, which is not allowed. So your on-board clocks MUST run more slowly. But its not just the clocks, its time itself. All of the electrochemical processes in your body slow down too. Hence, you age more slowly and that's what leads to the twin paradox.
- Graham PLv 59 年前
Time dilation is tricky.
Take the example of two ships passing at high speed.
Each ship will feel at rest and assume the other ship is moving fast.
Time on the other ship is slowed by your view. You assume your time is fast from his perspective
BUT people in the other ship think your time is SLOWED.
When you slow the difference in speeds things magically sort themselves out.
It is during the accelerations and decelerations that fixes things.
- KoshkaLv 59 年前
Yes? yes.
Zap!
資料來源: Information seems to have passed outside of 'isolated' system (chunks/rimshot/cough-cough-spit hairball) after all, as your replies NOW seem to indicate some adiabatic access to it (the now 'zapped' past). The traces (bits of information) you left points to evidence that a conversation about a thought experiment on possible 'time warps' did occur. The only way to retrieve it (the past) would be IF it was C&P, printed or downloaded, whuch is most likely improprable. It was fun to give you a hard time and 'your contact' would have enjoyed giving Feynman a hard time, too. He might have explained and chances are he would say: 'If you don't like it, go somewhere else' =)