Would you like a short demonstration of the theory of relativity?

Question

I was asking some questions yesterday about relatiivity and it seemed that some folks in R&S don't 'believe' in it. And while much of it is complicated, the basic building blocks of it can be demonstrated by thought experiments (this is actually how Einstein did some of his early work).

Here's one example I posted last night (I've altered it just a little bit):

Imagine you are sitting in a train that is leaving town. Your seat is facing backward and you are looking back at the clock in the town square. Just as the clock hits 1:00:00, the train instantly accelerates to the speed of light. You continue watching the clock. What do you think happens?

It's a simple example, but it provides a glimpse as to why time is relative. Even though the clock continues to move, you only see it at 1:00:00:

If you slowed down just a fraction, the clock would move, but the rate of movement that you saw would be much slower than the rate of movement of somebody still and observing the clock.

Clair, when the train stops, you are back in the same relative frame as the clock.

It would feel like the blink of an eye. You have to go deeper into the theory to see this. And I don't claim to fully understand to the point that I can expaln it. But mathematically, it has to be that time slows down.

BTW, Relativity has been demonstrated in an umber of astronomical measurements - including the relativity of time.

Answer 1

I like the example Penrose gave in 'the emperor's new mind' with the astronaut falling in to it. It explained special relativity and the event horizon in one swoop. I dont know, maybe it only worked because I'd read Hawking first.

I'd be happier if you explained evolution - lol - might save us from answering a lot of dumb questions!

Answer 2

"Imagine you are sitting in a train that is leaving town. Your seat is facing backward and you are looking back at the clock in the town square. Just as the clock hits 1:00:00, the train instantly accelerates to the speed of light. You continue watching the clock. What do you think happens?"

Well, after a nanosecond I would not see the clock anymore, duh! In one second I would've moved 299,792,458 meters.

Anyway, I get your point, frame of reference of the observer and all that ;)

Answer 3

Right. If it moved at the speed of light, I would keep looking at that number.
But for how long is it moving at the speed of light and when it stops, what does the clock say?
If it was moving for say three minutes and 23 seconds at the speed of light, it would go from saying 1:00:00 to 1:03:23 and how long would it feel to you?
would it feel like the blink of an eye went by in that three minutes or would it feel like three minutes?

Answer 4

Well, how about this, --The conductor comes by your seat and says that when the train stops you will die because he heard from maintenance that the brakes can't support that amount of speed and it cannot stop without a disaster but the engineer says over the intercom that he has heard what the conductor has said but, he doesn't think that is true so he will continue on his way. Who do you believe? At that point do you think there is an absolute truth?

Answer 5

if moving at the speed of light for three minutes and 20 seconds, the clock would move one second for one second, but because i am traveling at the same speed as the light at that 1:00 mark, i wouldn't be able to see anything but that same image, i would think i would still be able to move my head around,

this of course is all an academic since no one has a machine that can go the speed of light,

heres some more relativity for you,

e=mc2

i dont think the human ever will becaues it would require too much energy to get the mass of the human and the machine to go that light speed,

its worth trying cause of the benefits to technology in trying but ultimately i think we would fail,

funny cause electrons go that light speed all the time, "or do they?"

unified theory and all

Answer 6

Relativity is the idea that observations count number on the body of reference. some examples: - The classical relativity concept (Gallilei, Newton): the speed of an merchandise relies upon on the speed of the observer. in case you go by potential of one hundred kilometers per hour even as bypassing a automobile that is going by potential of ninety km/h, you be conscious the different automobile as going 10 km/h backwards. - The particular relativity concept (Einstein, Lorentz): also the mass of an merchandise, the time between events etc. relies upon on the article's velocity relative to the observer. also, the classical relativity concept is somewhat faulty (in uncomplicated words significant for extraordinarily extreme speeds). - the speed of sunshine isn't relative (Einstein, Michelson, Morris): no count number who observes a photon in vaccum, all of them agree that it strikes by potential of three*10^8 meter per second. E=mc^2 isn't the most perfect area of the concept of relativity yet likely were given wide-spread because it really is so uncomplicated. It says that mass and potential is "an identical". The consistent of proportionality is c^2 or 9*10^16 joule per kilogram.

Answer 7

Let me see if I can understand what your saying. You are saying that if an astronomer was to see a star being born 100 million light years from earth, if he was to get on that train travailing at the speed of light and go to that star he would get their to see the star born as if time stood still?

Answer 8

Time observed is relative.
Time cannot stop.
The clock continues irregardless of observation.
The same clock on the train would move at the same time as the one at the station.

What is your point?

Answer 9

Well, in my reading... two trains are moving at a different direction, and you could still see the person in its wholeness and entirety... which proves the bends of lights.

As from your point of view, I believed that it was basing it on another object is the basis of that. As it was explained that no objects are moving without its basis.

Peace.

Answer 10

A student riding in a train looks up and sees Einstein sitting next to him. Excited he asks, "Excuse me, professor. Does Boston stop at this train?"