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Sean Clayden
2006-Sep-26, 02:25 PM
Is it possible to travel faster than the speed of light. If not, isn't space travel outside our universe pointless ??

http://home.sunrise.ch/schatzer/space-time.html

antoniseb
2006-Sep-26, 03:25 PM
isn't space travel outside our universe pointless

I'm not sure what you mean here. So far as I know no one has attempted to travel outside our universe, or made any plans to do so.

Ronald Brak
2006-Sep-26, 05:02 PM
I'm sure Sean means solar system.

There are lots of ways around the problem. Develop immortality, freeze yourself during the trip, download yourself into robotic bodies and so on.

Then there is simply travelling at relavistic speeds so a thousand light year trips might only take a few years of subjective time. Of course travelling that fast will be tricky.

Sean Clayden
2006-Sep-26, 06:42 PM
http://home.sunrise.ch/schatzer/space-time.html

Interesting theory on light travel and beyond.

Sean Clayden
2006-Sep-26, 06:45 PM
What I meant was, if to travel at the speed of light was possible it would take too long to get anywhere.

Is the speed of light the ultimate velocity ?.

Sean Clayden
2006-Sep-26, 06:49 PM
If you were to travel away from the earth faster than the speed of light to a predetermined point, could you look back at the earth and potentialy see its creation ?

Sean Clayden
2006-Sep-26, 06:50 PM
Please explain relevistic speed ?

Ronald Brak
2006-Sep-26, 07:12 PM
Please explain relevistic speed ?

Well, basically the closer you get to the speed of light the slower time moves for you. So if you had a ship that could travel at close to the speed of light then you could travel to a distant star and one year might pass for you while a thousand years could pass for everyone back on earth.


If you were to travel away from the earth faster than the speed of light to a predetermined point, could you look back at the earth and potentialy see its creation ?

Well, since time your personal time slows down as you approach light speed some people think that if you traveled faster than light time would go backwards. However there is no way we can see that it is possible to travel faster than light.

If you search around I'm sure you'll find better explanations on the net.

Doodler
2006-Sep-26, 08:23 PM
Travelling at near the speed of light is plenty fast enough to get you anywhere locally, from the perspective of the traveller.

antoniseb
2006-Sep-26, 09:02 PM
Travelling at near the speed of light is plenty fast enough to get you anywhere locally, from the perspective of the traveller.
But not from the perspective of the person paying for it, or hoping for some kind of fiscally worthy result.

Van Rijn
2006-Sep-26, 09:17 PM
But not from the perspective of the person paying for it, or hoping for some kind of fiscally worthy result.

Exactly, and assuming it was technologically possible, there would be an enormous cost in energy, as well as very impressive particle shield requirements.

Doodler
2006-Sep-26, 10:37 PM
But not from the perspective of the person paying for it, or hoping for some kind of fiscally worthy result.

That'll depend entirely on who writes the check, and where they are when it launches. :)

Sean Clayden
2006-Sep-27, 02:02 PM
Exactly, and assuming it was technologically possible, there would be an enormous cost in energy, as well as very impressive particle shield requirements.


Send me a picture and then I can tell you there isn't.

Sean Clayden
2006-Sep-27, 02:03 PM
I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Send me a picture and then I can tell you there isn't.

01101001
2006-Sep-27, 04:58 PM
Send me a picture and then I can tell you there isn't.
Van Rijn's yard (http://www.bautforum.com/showthread.php?t=39521). Good luck.

Sean Clayden
2006-Sep-27, 05:18 PM
no elf there, must not be seeing things

Sean Clayden
2006-Sep-27, 05:29 PM
http://www.phys.unsw.edu.au/einsteinlight/jw/module4_time_dilation.htm

I'm sure that light does not change dependent on what angle you are looking at an object.

ie. if you were on Earth observing a star 10 light years away and at the same time a second observer was looking at the same star from Pluto. would what you are seeing different. I would assume that the difference in time is the distance between pluto/speed of light.

I don't see how the speed of light can slow time.

Sean Clayden
2006-Sep-27, 05:48 PM
http://www.phys.unsw.edu.au/einsteinlight/jw/module4_time_dilation.htm

I'm sure that light does not change dependent on what angle you are looking at an object.

ie. if you were on Earth observing a star 10 light years away and at the same time a second observer was looking at the same star from Pluto. would what you are seeing different. I would assume that the difference in time is the distance between pluto/speed of light.

I don't see how the speed of light can slow time.

Traveling faster than the speed of light, which is impossible, I can comprehend that can change time.

Dragon Star
2006-Sep-27, 10:00 PM
Mentioning causality (http://en.wikipedia.org/wiki/Causality_%28physics%29) would probably be beneficial to your understanding.

Van Rijn
2006-Sep-27, 10:48 PM
no elf there, must not be seeing things

Not visible, at any rate. As everybody knows, invisible elves don't photograph well.

PhantomWolf
2006-Oct-02, 02:58 AM
But not from the perspective of the person paying for it, or hoping for some kind of fiscally worthy result.

How about we send all the politicians on the planet to set up a colony somewhere else?

Ronald Brak
2006-Oct-02, 05:10 AM
How about we send all the politicians on the planet to set up a colony somewhere else?

Yes but the people who decide to send them there are making a political decision and are obviously politicians themselves.

Chip
2006-Oct-02, 09:09 AM
What I meant was, if to travel at the speed of light was possible it would take too long to get anywhere.

Is the speed of light the ultimate velocity ?.

You don't have to travel "at" the speed of light, just very close to it, and say good bye forever to all friends you leave behind - (or bring them with you.) Mass becomes infinite at the speed of light so it is not feasible for matter to travel at that speed, however physics does not forbid in principle material traveling somewhat close to light speed. (Current engineering does not allow this.)

To get a hypothetical spaceship to travel near "c" (light speed) would require quite a few technological hurtles and also likely involve transforming from one technology to another. Despite Star Trek, acceleration would have to accommodate human physiology. And then there is the whole relationship of relativity. Time dilation could mean a trip of six months to you could take a million years on Earth. (That's why you'd better take your friends, favorite movies, comicbooks and favorite snack foods with you. They won't be there if/when you ever return to Earth.)

The thing to remember is when a light beam travels at lightspeed away from you to a star four light years distant, it takes four years to reach the star from your perspective, but for the light beam the trip is instantaneous.

If a very fast spaceship leaves somewhat near the speed of light, it might take 8 years to travel four light years away from your perspective, but from the crew's perspective, the trip might last a week.

Ronald Brak
2006-Oct-02, 09:20 AM
Pssst... Chip! Brak here. Might want to change that last sentence to, "...it might take just over 4 years to travel four light years away..."

I know you have a lot on your forehead bulges and it's easy to make a little mistake like that. I'm just trying to help out, don't go sending the Mute Ant after me.

Chip
2006-Oct-02, 04:37 PM
Pssst... Chip! Brak here. Might want to change that last sentence to, "...it might take just over 4 years to travel four light years away..."

I know you have a lot on your forehead bulges and it's easy to make a little mistake like that. I'm just trying to help out, don't go sending the Mute Ant after me.

Hey Brak - haven't heard from you since Metaluna blew. (The Monitor was ****ed about you blowing up the Professor from Gilligan's Island in that pickup truck. But don't worry, he's toast too.)

Well, I was guessing when I said: "...very fast spaceship leaves near the speed of light, it might take 8 years to travel four light years away..." I should have defined "near" lightspeed with more precision. But OK, very very near lightspeed could be just over 4 years.

Mute Ant settled down, now owns a small restaurant in Chicago.

Doodler
2006-Oct-02, 10:24 PM
But not from the perspective of the person paying for it, or hoping for some kind of fiscally worthy result.

How about we send all the politicians on the planet to set up a colony somewhere else?


Because some dimwit will go and elect more of'em....

Sean Clayden
2006-Oct-03, 01:50 PM
[QUOTE=Chip;836881]You don't have to travel "at" the speed of light, just very close to it, and say good bye forever to all friends you leave behind - (or bring them with you.) Mass becomes infinite at the speed of light so it is not feasible for matter to travel at that speed, however physics does not forbid in principle material traveling somewhat close to light speed. (Current engineering does not allow this.)

To get a hypothetical spaceship to travel near "c" (light speed) would require quite a few technological hurtles and also likely involve transforming from one technology to another. Despite Star Trek, acceleration would have to accommodate human physiology. And then there is the whole relationship of relativity. Time dilation could mean a trip of six months to you could take a million years on Earth. (That's why you'd better take your friends, favorite movies, comicbooks and favorite snack foods with you. They won't be there if/when you ever return to Earth.)

"Does this mean you go faster than the speed of light? No. From the point of view of a person at rest on Earth, you never go faster than the speed of light. From your own point of view, distances along your direction of motion are Lorentz-contracted, so distances that are vast from Earth's point of view appear much shorter to you. Fast as the Universe rushes by, it never goes faster than the speed of light."

http://casa.colorado.edu/~ajsh/sr/wheel.html

Bokmakierie
2006-Oct-03, 02:36 PM
I like to play this little mind game.
500 years ago on a planet orbiting Antares, their "André Agassi" serves on court A. An intrepid cameraman decides to send the image towards Sol. The image reached me yesterday on my sattelite dish. What did I see? I saw "Agassi" serving the ball. For 5oo years time never changed on that beam of light or, better still, on the photons carrying the information towards my sattelite dish.

Phil

Chip
2006-Oct-03, 07:18 PM
...Does this mean you go faster than the speed of light? No.
http://casa.colorado.edu/~ajsh/sr/wheel.html

That's right. I wrote: "...a hypothetical spaceship to travel near "c"..."
("Near", but below the speed of light. "Hypothetical" also acknowledges the fact that its hard to do.

Sean Clayden
2006-Oct-03, 09:46 PM
That's right. I wrote: "...a hypothetical spaceship to travel near "c"..."
("Near", but below the speed of light. "Hypothetical" also acknowledges the fact that its hard to do.

Agassi will not return serve..........lol :( :sad:

tofu
2006-Oct-04, 06:11 PM
How about we send all the politicians on the planet to set up a colony somewhere else?

Or how about, we freeze the politicians and take them to another planet on DC-9's, where we drop them into a volcano which we cause to erupt by setting off H-bombs. Then we capture the politicians' spirits and brainwash them, then turn them loose on the native inhabitants.

ToSeek
2006-Oct-05, 06:02 PM
Moved from "Life in Space" to "Q&A."