My wife and I have been discussing Space my question is this?

Question

I say that if you travel from Earth on a rocket ship for a number of years time on Earth moves on more rapidly than time on the ship if you are travelling at the speed of light, for example Spacecraft travelling 5 years Earth time 20 years. Am I correct in this as my wife says im talking alolt of drivel, and if I am could you explain why im right thanks.

Answer 1

You are correct. Einstein theorised that, as you approach the speed of light, time slows for you.
this has been proved by comparing 2 atomic clocks - four of which was taken into aircraft and flown at high speeds (although only a tiny, tiny, fraction of the speed of light). The clock of the aircraft were different to reference clocks on the earth, by a fraction of a second

quote - from http://www.sfsite.com/fsf/2006/pmpd0604.htm
"In October 1971, two physicists flew four atomic clocks on commercial airliners twice around the world, once in an easterly direction, and once in a westerly direction. These clocks were accurate to within a few nanoseconds. (That's mighty accurate since there are 1,000,000,000 nanoseconds in a second.) Using calculations from the special theory of relativity, the physicists predicted how time measured by the clocks on the planes would differ from time measured by clocks on the ground. What do you know! The experimental results matched the predictions, confirming that time dilation actually does take place with real clocks."

It really pains me how people can give 'answers' which are based on their own tiny, uneducated minds, without bothering to even do a quick google search..... their ethos seems to be "If I can't understand it, it musty be wrong".... no wonder creationism and 'Intelligent design' are gaining ground in western society

Answer 2

You're correct, the theory goes that time will seem the same on the ship, but from an external view will have slowed down on board the ship. The astronauts will think that only a month or so has passed , but in reality, years have passed on Earth.

Nobody knows what the rate of this would be, so the astronauts could return to Earth after mankind has died out!

"If information could travel faster than c in one reference frame, causality would be violated: in some other reference frames, the information would be received before it had been sent, so the 'effect' could be observed before the 'cause' is. Due to special relativity's time dilation, the ratio between an external observer's perceived time and the time perceived by an observer moving closer and closer to the speed of light approaches zero. If something could move faster than light, this ratio would not be a real number. Such a violation of causality has never been observed."

Answer 3

Confident assertions that a thing is not so, do not make it not so. They do not have the status of facts, merely that of assertions. And they just confuse people and slow down the emergence of the truth.

It seems very few people have any understanding of the Special Theory of Relativity, your wife included. The person travelling near to the speed of light will age more slowly than the person left behind on earth. This is often referred to as the Twins Paradox.

A good way to think of it is that if you travel some distance at near the speed of light and then return to earth, is that your children, left behind on earth could well be older than you, when you get back, Certainly nearer your age, Your body clock will have meantime ticked more slowly than theirs. That is what is meant by time dilation.

An amusing little limerick that deliberately overstates this idea:

There was a young lady called Bright
Who could travel faster than light
She set out one day
In a relativistic way
And came back the previous night

It is pver a hundred years (1905) since Einstein first proposed the Special Theory of Relativity (1). Hasn't word got round yet? I knew about it as a teenager, nearly fifty years ago.

Here is some more news from that epoch that some contributors above and your wife might like to catch up on, too. Mafeking (2) has been relieved!

Answer 4

Yes, one of the insights of the Special Theory of Relativity isthat time is not a constant. Time is only relative to the oberserver's frame of reference. This has been proven by various experiments. One of which took two synchronized atomic clocks, left one at the lab and put the other on a jet. When the two clocks were brought back together, they were no longer in synch--they were a few billionths of a second off. The one that had been moving was a little behind. Time passes more slowly for a moving observer. But, for this to be significantly noticed, one must move at a large fraction of the speed of light.
The reason neither space nor time is an absolute when talking relativistically can be loosely explained by the simple equation for speed. Speed = distance/time
Well, if you plug in "c" for speed --"c" being the speed of light in a vacuum or a constant value, then you can manipulate the equation and realise that both d and t can have numerous different values--based upon the measurer's/observer's location relative to a gravity well and state of motion. And, "c" has been precisley measured numerous times in various experiments. So, say you are "stationary" in a frame of reference and turn on a flashlight. You would measure the photons moving away at "c". Now, say another observer is moving towards you from a distance away and decides to measure the photons speed. That observer would also measure them at "c", not observer speed plus "c", but always exactly "c". How is this possible? It makes no sense. But the moving observer's "time" is different than your "time" So, when plugged in to the equation you would both get "c" as a result using your different "d" and "t" values. Also, another observer moving away from you would measure the photons at "c", not "c" minus away speed. Time dilates and space warps. "c" is the only absolute constant.
Just research about the Special Theory, not the General Theory, of Relativity. There is quite a lot lot of information about it.

Answer 5

Time is a constant, it never changes. Just because you travel faster, it doesn't mean that time moves faster, same for the opposite. If you travel 5 years in a spaceship, then 5 years have passed on earth. If you travel at the speed of light, then you will be 5 light years from earth. Boils down to you are wrong.

Answer 6

The way you phrased the situation is incorrect.
Also, how did you get that conversion factor....5 years on a space ship = 20 years on Earth?

To briefly correct you,
all measurements need to be taken in a particular reference frame...in your case the reference frame (I assume) is Earth.
As the space ship approaches the speed of light, as seen by an observer on Earth, time begins to slow down (as seen on Earth). The closer the space ship is traveling to the speed of light, the more time appear to slow down from Earth. If (I say if because nothing with mass can ever actually attain light speed) the space ship gets to the speed of light, time would become 'infinitely dilated' and appear to stop completely as viewed from Earth.

Notice how many times I referenced Earth in the observations....this is important because if one was to change it around and make all the observations from within the spaceship the situation would change complete. The person inside the space ship would sense nothing is wrong with them however they would look onto Earth and see that time is speeding up from his perspective.

The amount of time dilation depends on the velocity of the object relative to the observer. One cannot just say that a space ship is traveling at 90% the speed of light since that assumes an absolute frame of reference, one needs to say that the object is travleling at 90% of the speed of light as seen from Earth.

Answer 7

You can travel as close to C as you like but you can never travel AT C because the energy required to do so would turn you into an infantly hot,dense mass. Time flows at a constant speed. It is your perception of time that changes relitive to your point of observation due to the time dilation effects of travelling so close to C.

Answer 8

Perceived time inside the ship would mimic Earth's while actual time outside the ship would be moving faster-or so Einstein theorized.

Answer 9

Drivel.

Time only exists because we keep counting it. Unless you created your own time on the ship and counted slower or faster, you would have counted the same number of years as everyone else when you got back no matter how fast you went.

Answer 10

You are wrong. You gain time and loose time and come back to the same time on earth. Like going from west to lax to east Ny and back. You gained 3 hours but lost when back at LAX.