what do u think of Albert Einstein's theory of relativity????

Question

hi I was thinking about the speed of light and Albert Einstein's theory of relativity. Now im not really into books and stuff and i go to an art school so this is totally out of my rage.But ill give it a shot .So lets assume that a space ship is going from point A to point B and the distance between is 1 year light.So the ship has to go at the speed of light to make it for one year to point B!! but since the theory don't allow the ship to go at the peed of the light because x factor ,,the ship will be going 70% the speed of light and it should be able to get to point B for little over a year but as the theory says ;time passes faster on earth than the space ship which is traveling at 70% the speed of light .I don't have the skills to figure it out how many years have passed on earth but a guess is 10 years.now imagine we can see the ship for all the distance it did and the ob vies answer is that we see the ship going 10 times slower than the speed of light . So what do u think????

what im saying is ;!!! 1 if throw a telescope we could see the ship going to point B !!! than we would see the ship going slow right ? because on earth are passing many years right ?? correct me if im wrong

Answer 1

Here's part of an explanation which may or may not help. It explains one of the effects of relativity.

Assume that Einstein was right when he said that light appears to travel at the same speed for every observer, no matter how fast or which direction they're moving.

Assume also that the speed of light is 200,000 miles per second. I know that's a bit fast, but it makes the calculations easier, and I'm just demonstrating the idea.

You are looking up at the sky. You see an alien spacecraft travelling from your left to right at half the speed of light, 100,000 miles per sec.

You see the craft send out a light beam in front of them. You see it travelling at the speed of light. They see it travelling at the speed of light.

1 second later for you, you see the light beam is 200,000 miles from where they sent it. In that time, though, the craft has travelled 100,000 miles. So after one second, the light is only 100,000 miles in front of them.

1 second later for them, they see the light beam is 200,000 miles ahead of them.

BUT, if the light is 200,000 miles ahead of them, YOU would see it 300,000 miles from the point of origin. For you, this must be 1.5 seconds after they sent it out.

In other words, when one second has passed for them, 1.5 seconds has passed for you. This is the effect that travelling very fast has on time.

Now, I can't get my head around why that means a 10 light-year journey at near-light speed doesn't fell like ten years to the traveller, while it does seem to take that long to someone watching the journey from a distance. Over to someone else...?

Answer 2

First of all, your estimate of 10 years if way, way off. Someone else has provided the answer for you but it doesn't take a genius to figure out that if you travelled at 50% the speed of light, a distance of 1 light year would take two years to traverse, so obviously traveling at 70% will take even less time.

Relativity is all about "frames of reference" or perspectives. When I say the journey at 50% of light speed takes two years, I mean two years from the perspective or reference frame of an observer on Earth. To the pilot of the spaceship, the journey would have been shorter in his or her reference frame due to the time dilation effects of special relativity. Travelling at 70% light speed would result in a more substantial dilation effect.

So to answer your question, an observer on Earth would not see the ship travelling slowly. They would see it travelling at 70% the speed of light.

Answer 3

OK, the star is 1 light year away and the spaceship is going 70% of the speed of light. For the earth, the voyage takes 1/.7=1.42 years.

For the spaceship, the time goes slower by a factor of sqrt[1-(.7)^2]=.7, so the journey takes (1.42)(.7)=1 year according to it.

Your numbers are unusual in that the speed and the time dilation factor are the same. This happens at 70% of the speed of light, but not at other speeds.

Answer 4

If a ship is traveling at 70% light speed, it will take it 1.42 years to travel 1 light year. What Einstein's theory says is that is observer X is moving relative to observer Y, observer Y will see that time has slowed down for observer X. So, using your example, a person on Earth will observer time slow down for a person on the ship. The Earth observer will also notice that the ship is shortened in the direction of travel so that, if the ship is 100 meters long in the direction of travel, the Earth observer will see that the ship is less than 100 meters.

The weird part comes about when you realize that motion is relative. The person on the ship notices that the person on Earth has her time slowed down and she is shortened in the direction of her travel... which is 70% light speed relative to the ship.

If the ship returned to Earth, the round trip will take a total of 2.84 years (ignoring speed up and slow down times). The person on Earth will have aged 2.84 years. The person on the ship will have aged a lesser amount. The reason the ship person aged less is because of the shortening effect. To the person on the ship, the 1 light year destination was shortened, so the ship (from the ship person) traveled less than 1 light year (less that 2 light years for the round trip). So, he was out in space for less than 2.84 years and so, aged less.

Finally, at 70% light speed, these effects aren't all that great. Time is slowed so that 1 second on Earth equals 1.4 seconds on the ship (assuming I did the math right)

Answer 5

By extrapolation of James Clerk Maxwell's equations, Einstein realised a funny thing about a quanta of electromagnetic radiation, or photon. Every observer in any frame of reference will always measure the speed of a photon in a vacuum as a constant, usually labelled "c". Now, any high school physics student will tell you the equation for speed is s=d/t or speed equals distance divided time. In our slow moving existence, a distance in space and an interval of time are pretty much constant with an object's speed being the calculated variable. This does not apply at relativistic speeds. No matter the state of motion of the observer nor the state of motion of the source of the light, the speed of the photon will always be constant. This must mean that time and distances do not remain the same. They don't; time dilates and space contracts relative to the observer's state of motion
Another aspect is that our total energy of motion through space multiplied by our total motin through time will equal c. Again, in our normal slow moving life, most of our motion is through time. The faster you move through space, the less you move through YOUR time by someone else's observation. But, time and space are relative to the frame of reference of the observer. Two observers in two different frames of reference can observe the same thing and measure different values for time intervals and distance and, here's the really headache inducing bit, BOTH observers are absolutely correct. Both the person on earth and the person on the ship will have the same definition for how long a second is. Both will have clocks ticking away one of their seconds at a time. When the person on the ship slows down to same speed and frame of reference, and the clocks are brought back together, they will say differing amounts of seconds have elapsed for the whole trip, but they will both begin measuring the same interval of a "second", cause they'll both now be in the same relativistic frame of reference again. hrmm, in other words, a "second" is a second for everyone relative to their clock, but not everyone's second may equal everyone else's.

Answer 6

Whatever it is, your (or my) intuition won't help. But I think the effective equation is sqrt ( 1- (v/c)^2 ) so it would be 9.8 years. Somebody who really knows, feel free to correct me!

Answer 7

If the theory is right, we need not have crafts flying from one area to the other; we can stay in the atmosphere above earth from our place, say Australia and when Africa appears, descend...... May be a dumb answer.

Answer 8

I think it graduated into The LAW of Relativity.

Answer 9

I don't get it. I think you should re-phrase your answer to be more clear and concise. However, I don't see anything in Einstein's Theory (E=MC^2) that says that time passes faster on earth than space...

Answer 10

time passes fast when your busy & slow when your not