Time Dilation and Deep space travel

I was watching the show Cosmos with Carl Sagan the other night and he was talking about near light speed travel and the effects of time dilation. For people that dont know what time dilation is I'll try to explain it as simply as I can. The faster you go the slower time gets. This effect has been proven with various experiments.

Getting back to Carl Sagan he said that if you had a ship that could travel near lightspeed say 99.9% LS (and theres no law that stops you from doing that) that you could travel to the center of the Milky way Galaxy from earth in 21 years your time But back on earth 30,000 years could have passed for the rest of us. Time would have slowed down so much for you on the ship that 30,000 years would be like 21 years for you.

He even went on to say if you pushed even closer to LS that you could in theory travel the entire known universe in something like 59 years your time but back on earth 10 billion years would have passed and the earth and sun would be long dead.

Was Carl Sagan correct? are the effects of time dilation near Light Speed that drastic? If so I have to say thats simply amazing that means humans can travel to the far reaches of the universe without any faster then light loopholes and still be alive for the end of the trip.

Originally posted by ShadowXIX

Was Carl Sagan correct? are the effects of time dilation near Light Speed that drastic? If so I have to say thats simply amazing that means humans can travel to the far reaches of the universe without any faster then light loopholes and still be alive for the end of the trip.

And when you get back, there will be no one left on earth to share the celebration booze with! ha.

Serisouly though. That's cool stuff. Is Nasa gonna test this in real life I wonder...if they ever get a ship to that speed...maybe by putting a monkey in space to the kupier and then back, mean while, 500 years later, when he gets back, we'll all have forgotten abou tit, and we'l think he's an alien, hahaha. I'm sorry for jacking the thread.

Carl Sagan's 'Cosmos' is an awesome program though.

The real problem is that even though time slows down, your life span is cut to about 1 millisecond and you die about the same time as all your cohorts. That is, if your spaceship doesn't collide with a microscopic piece of space dust first.

Originally posted by GradyPhilpott
The real problem is that even though time slows down, your life span is cut to about 1 millisecond and you die about the same time as all your cohorts.

Where did you get this from? If time slows down aging slows down as well.

How do you know that? Einstein said that time as measured by clocks slows down, but clocks don't measure time. All clocks have one thing in common--they move! We calibrate them and call it time. If time as measured by clocks slows then all that really happens is that everything that moves slows down. That doesn't mean you live longer.

Entropy is time. They have shown that the faster a particle goes the slower it decays. The same would apply to humans.

NASA has conducted experiments with synchonised atomic clocks both on the ground and on the ISS which is travelling in space much faster then the one on the ground, since we have no to the picosecond measurment to measure an Astronaughts age Atomic clocks will have to do. They found that the time dialation confirmed Einsteins theories in that respect.

[edit on 11-11-2005 by sardion2000]

[edit on 11-11-2005 by sardion2000]

Particles decay more slowly and cesium atoms oscillate more slowly, that says nothing about the life of a man, his corpse, perhaps, but not his life.

Carl sagan said that with time dilation all clocks would slow even biological clocks. Our bodies are one big biological clock.

Slowing down time would slow down every function in your body down to the rate cells divide.

Link

Originally posted by GradyPhilpott
The real problem is that even though time slows down, your life span is cut to about 1 millisecond and you die about the same time as all your cohorts.

Do you have ANYTHING to back this up?

Well I still stand by my statements as it there is 1. Wide support throughout the Physics community and 2. Experimental Evidance that helps to validate it. It won't be 100% confirmed until we develop an ultra-sensitive age measurment for biological organisms, but one way to get started is to send up some short lived creatures(very very short lived creatures) and see if they live longer on a Artificial Gravity well module on the ISS (or even a seperate station) to simulate conditions on earth put it into a very fast orbit and see how long they live. Elaborate experiment yes but it would prove conclusively what you doubt.

[edit on 11-11-2005 by sardion2000]

Heres a good explaination of why we age.

Your body is made up of around 100 million million cells. Some of them, including brain cells, are rarely replaced. Others are constantly replaced, as existing cells multiply to make new ones. However, each cell can only multiply a certain number of times before it dies. As more cells are lost or damaged, you start to show signs of ageing. For example, the fewer skin cells you have, the thinner your skin becomes.

Slowing time would slow the rate at which cells replicate by slowing down whatever chemical reaction cause them to do that. Slow that rate and you slow the ageing process.
link

Originally posted by GradyPhilpott
How do you know that? Einstein said that time as measured by clocks slows down, but clocks don't measure time. All clocks have one thing in common--they move! We calibrate them and call it time. If time as measured by clocks slows then all that really happens is that everything that moves slows down. That doesn't mean you live longer.

That's actually exactly what it means. Because time is relative. From the Earth's point of view, 30,000 years have passed and time has slowed down for you. From your point of view, time is normal and time on Earth has just sped up dramatically. Technically, you've only lived another 21 years from your point of view. And from Earth's point of view, it's lived another 30,000 years.

Originally posted by Esoterica
That's actually exactly what it means. Because time is relative. From the Earth's point of view, 30,000 years have passed and time has slowed down for you. From your point of view, time is normal and time on Earth has just sped up dramatically. Technically, you've only lived another 21 years from your point of view. And from Earth's point of view, it's lived another 30,000 years.

Excellant explanation I was struggling to explain It's exactly as Einstein said it(or near enough anyway)

Originally posted by Amuk

Originally posted by GradyPhilpott
The real problem is that even though time slows down, your life span is cut to about 1 millisecond and you die about the same time as all your cohorts.

Do you have ANYTHING to back this up?

Amuk! Long time no see!

That statement was made tongue-in-cheek. Still, there is nothing in the theory of relativity that suggests that human travel at or near "c" is possible or that doing so would make one live longer. There's no reason not to suggest that at those speeds a man would have the lifespan of a fruitfly.

First, time dilation has never been proven, second, it doesn't exist. In the case of the twins, they will always be relative to each other, so I don't see why the one twin doesn't age as much as the other.

I would really love to hear the chemistry and biology behind this from any believers.

Originally posted by GradyPhilpott
That statement was made tongue-in-cheek. Still, there is nothing in the theory of relativity that suggests that human travel at or near "c" is possible or that doing so would make one live longer. There's no reason not to suggest that at those speeds a man would have the lifespan of a fruitfly.

Frosty
First, time dilation has never been proven, second, it doesn't exist. In the case of the twins, they will always be relative to each other, so I don't see why the one twin doesn't age as much as the other.

I would really love to hear the chemistry and biology behind this from any believers.

You two are obviously very ignorant of what you're trying to talk about.

Time Dilation Experiment: Proof of Time dilation

I will say it again Time is relative. This has been theorized and proven. If you two can't comprehend what relativity means, that's not your fault. But apparently neither of you have even tried to understand it.

Originally posted by Esoterica

Originally posted by GradyPhilpott
That statement was made tongue-in-cheek. Still, there is nothing in the theory of relativity that suggests that human travel at or near "c" is possible or that doing so would make one live longer. There's no reason not to suggest that at those speeds a man would have the lifespan of a fruitfly.

Frosty
First, time dilation has never been proven, second, it doesn't exist. In the case of the twins, they will always be relative to each other, so I don't see why the one twin doesn't age as much as the other.

I would really love to hear the chemistry and biology behind this from any believers.

You two are obviously very ignorant of what you're trying to talk about.

Time Dilation Experiment: Proof of Time dilation

I will say it again Time is relative. This has been theorized and proven. If you two can't comprehend what relativity means, that's not your fault. But apparently neither of you have even tried to understand it.

I understand relativity, I don't understand Einstein's relativity.

There were so many things wrong with that experiment. Einstein's time dilation relates to obtainig near light speed velocities not miniscule fractions of it, right? Cs Clocks are also unreliable and are known to compromise their integrity when exposed to cosmic rays (like up in the air). It is even stated in your article that they are attempting ot make improvements. If the clocks were already off by nanoseconds what would be the point in running an experiment which relies on a difference of nanoseconds between two clocks?

Of course time is relative, but what are the biological implications to suggest that one person won't age as much as the other? Does anyone have a link to this?

If it takes 1 light year to reach a point from a planet in a spacecraft, and neglecting any difference in change of direction, it should take 2 years to go from this planet to the point and come back, right?. 2 years should pass for people on the planet too right? Not 40 or however many.

I can walk down and back up the street (and my friend stays at the point of origin), the same amount of time will have elapsed for me as that of my friend who stayed at the point where I started from, right?

[edit on 11-11-2005 by Frosty]

Originally posted by Frosty
I can walk down and back up the street (and my friend stays at the point of origin), the same amount of time will have elapsed for me as that of my friend who stayed at the point where I started from, right?

[edit on 11-11-2005 by Frosty]

Time dilation works at any speed even the 3MPH or so walking speed of humans. But it would be such a small fraction of a second you would never notice it.

Theres formulas to measure the time dilation effect at any speed. For example if you are in a plane going 550 MPH for six hours the time dilation effect is 0.000,000,01 of one second.

link

Plug your walking speed into that formula and you can figure out how much time dilation occured between you and your friend.

That would be cool to do hell it would be cool just to have flying cars but i don't see any of this being done while am alive and i am only 24. The reason i think this is because our government doesn't care about this stuff at all right now they all about war and #.

Well first off. Yes we have proved time dilation exists to some degree and all but proved it effects living organism's life spans.

The amount of time dilation at/near light speed really isnt known. It is rather guessed at. Many disagree about just how drastic it is. Imo we really wont know until we can accelerate and measure something at a decent fraction of light speed. Until then we do not really know how exponentially the effects ramp up.

Also you need to take into account that the normal "laws" of physics including Einsteins theories are turning out to not be nearly correct or inclusive. Faster then light travel of some sort has been measured. Certain particles do not follow current "laws" and behave radically and as of yet to us randomly. In the end many of the higher theories may be proven wrong.