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help I dont understand relativity
BahamutZERO
Registered User regular
Registered User regular
To peel this out of the tabletop thread: The speed of light is constant relative to reference points right? But what if a different reference point perceives the same object traveling at the speed of light, and that reference point is moving relative to the first one? My head hurts
BahamutZERO on
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Everyone sees light moving at the same speed
anyways I'm fairly sure this is where time dilation starts kicking in to even out the perception
What's not to understand?
What we call the speed of light (or c) is the speed at which all massless particles travel in a vacuum, it is the speed of causality
Do the same for three more hamsters, three more wheels. Attach the wheels to a tiny car. In the tiny car is a parrot wearing a bowler hat. The sun is setting in San Francisco, Toto by Africa is playing.
Oh yeah, look at it go. Honk honk, parrot driver, follow your dreams.
Special relativity has to be accounted for with GPS and communication satellites because of the speed they move compared to earth bound observers.
On one ship we had a comms officer who denied this was true while simultaneously using the calculations required to accurately contact satellites.
I struggle with that more than I do special relativity.
Why can’t causality move faster
This.
A good thought experiment to illustrate it is imagine riding on a train, and suddenly another train goes by in the opposite direction.
Both trains are traveling 100mph, but relative to you, traveling 100mph south, the other train is traveling 200mph north.
Similarly, if you're on the same train and pull alongside another train going in the same direction at 100mph, relative to you, the other train has zero speed.
Now imagine the trains are in a vacuum and capable of incredible speed. As you accelerate to approach the speed of light, the speed of the other trains relative to you change the faster you go, and yet, if you stood at the front of the train and shone a flashlight out the front, the light would accelerate away from you at the speed of light.
So you're alongside that train traveling in the same direction again, this time you are going .9C and the other train is going .8C. Relative to that train, you're traveling .1C, and if you and someone on the other train shone a flashlight out the front, the light would accelerate away from both trains at C, as if you were standing perfectly still.
Need some stuff designed or printed? I can help with that.
Now, you know one twin only tells the truth while the other only tells lies. What one question do you ask to determine which one is which?
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In relativity, any hypothetical particle moving faster than the speed of light "breaks" causality - it can be used to send signals into the past (this doesn't work in a single reference frame but starts to become very feasible as soon as you have at least two, for example earth and a spaceship traveling away from earth)
Einstein realized this early on and this is why Einstein is often associated with time travel in science fiction
As to why this speed limit exists in the first place, we don't really know, c is considered a fundamental physical constant
the sun is a sith got it
Only for the teensy bit of time it takes for it and everything around it to undergo some very drastic changes in its state of existence.
I believe the reference points experience however much time dilation relative to each other is needed to make everything line up.
If E=MC², how can photons have energy if they do not have mass? Anything times 0 should remain 0, right? Also, if photons are massless, how does light have mass? Or maybe what I should be asking is, what is the difference between a photon and light?
it'd be fucking sick as hell though
It's my plan for my funeral pyre
a photon has a rest mass of zero but is also has a rest mass of not zero and we kind of have to accept both of these as true because of they weren't it'd break a lot of other things we've measured
This video rules.
Accept oblivion, pet dogs.
Thanks. This doesn't really help me understand anything but I guess it's as as close to an answer I can understand as exists.
It's not likely that this is true and anyway it doesn't matter because all the math works either way, but it's neat to think about.
a photon carries a charge though
So it can sack a quarterback?
like, I don't want to live through it, but I'm interested to see how the world ends up in a couple decades.
could I conceivably get into some manner of satellite and orbit Earth fast enough that I can take a day long Klonopin nap and wake up 20 years later?
yeah, it's like the feynman video
basically, because theoretical physics is completely fucking insane and alien to anybody who does not study it, theres just some shit you kinda have to accept even if it sounds dumb as hell because there is absolutely no reference point
A lot of the way we think and talk about photons is an approximation for human convenience, because what stuff like the double slit experiment reveals about the underlying nature of reality super doesn't jive with how we actually experience that reality. So you get statements like "photons have a rest mass of zero but also a rest mass of greater than zero" which are nonsensical on their face because they're trying to break quantum field theory down into human language that's spectacularly ill-suited to describing it.