Orestes  wrote:
There is still the idea of wormholes and bending space. Which could make the whole process last only a few weeks or days. BUT that of course will not happen for centuries or probably never will. Travelling at light speed is not feasible because if you hit something at that speed, good night sweet prince.

I recommend a good set of anti-lock brakes.

Vivus Hussein Denuo wrote:

I recommend a good set of anti-lock brakes.

JJMiller wrote:
The worst part is that you could pick a cool destination, but even if you got there in a second you could discover that it had blown up a million years ago!

Another worst part is coming back from alpha centauri and you're still 25, whereas your GF is 83.  Awkward.

Vivus Hussein Denuo wrote:

Another worst part is coming back from alpha centauri and you're still 25, whereas your GF is 83.  Awkward.

Yes but if you make the trip at light speed there will be no real age difference. 4 years going 4 years back.....

Allen Carbon wrote:
I strongly believe that we will discover ways to travel faster than light. Maybe not in my lifetime but sometime in the distant future.

Remember when calculations were made that said nothing could possibly exist smaller than an atom? cause then it would cease to exist completely.

It's highly unlikely that we've reached the peak of our physics and technological science a hundred years ago.

Remember when astronomers and ship captains navigated around the world using the basis that the universe revolved around the earth? Then poof we discovered otherwise and all our navigation made even more sense!
I find it exciting to think that things could still evolve to blow all our calculations out the window.

If we go faster than light won't it get dark?

Brooklyn Bridge Images wrote:
Some pretty interesting stuff right here in our own solar system if you ask me

I agree with this.

There's tons of stuff in our own neighbourhood to explore...... We've got Jupiter, Mars, we could orbit Venus or Mercury if we get better technology and send ships to these places......

Oh and don't forget mining asteroids and Jupiter Lots of stuff there to pillage, er mine conservatively

Shadow Dancer wrote:
If we go faster than light won't it get dark?

Actually, from the perspective (frame of reference) of the passengers of a spaceship traveling at very nearly the speed of light, the headlights on the front of the ship would still "appear" to generate light moving away from the ship at the speed of light.  The passage of time on ship would be slower relative to time of an observer from outside the ship and distances as measured on board the ship will be shorter relative to the same distances as observed from outside the ship.  (edit:  See chapter XXII of Part 1 - the Special Theory of Relativity)

I will have to check my math tomorrow, but does that mean that distance/time (velocity) of the light from the headlights as observed on board......relative to velocity as observed from outside the ship will be the same?   It is just that from the ship the light will appear to be moving away from the ship at nearly the speed of light, but an observer from outside the ship would see a ship traveling at very nearly the same speed as the light from the headlights.

AdelaideJohn1967 wrote:

Yes but if you make the trip at light speed there will be no real age difference. 4 years going 4 years back.....

I think you are kidding, but if you travel at nearly the speed of light for twice as long, 8 years instead of 4 years, the time distortion will double, regardless of the direction you are traveling.

HHPhoto wrote:

I think you are kidding, but if you travel at nearly the speed of light for twice as long, 8 years instead of 4 years, the time distortion will double, regardless of the direction you are traveling.

Oh OK I thought the relativistic effects would be minimal...... My bad

Shadow Dancer wrote:
If we go faster than light won't it get dark?

Interestingly, all light that impinges on an object travelling at the speed of light will strike the exact front of the object. That is, from the POV of the object the entire universe appears to be a single really bright dot directly ahead of its direction of travel. This would continue to be true for objects travelling faster than the speed of light.

As the speed of the object decreases, the dot begins to grow.

Here are some examples of the effect: (from http://math.ucr.edu/home/baez/physics/R … eship.html)





An engineering implication of this is that, when building a light-speed or FTL ship, you only need to put your radiation shielding in the front of your vessel.

Lawrence Guy wrote:

Interestingly, all light that impinges on an object travelling at the speed of light will strike the exact front of the object. That is, from the POV of the object the entire universe appears to be a single really bright dot directly ahead of its direction of travel. This would continue to be true for objects travelling faster than the speed of light.

As the speed of the object decreases, the dot begins to grow.

Here are some examples of the effect: (from http://math.ucr.edu/home/baez/physics/R … eship.html)





An engineering implication of this is that, when building a light-speed or FTL ship, you only need to put your radiation shielding in the front of your vessel.

Great link... Thanks for posting.

AdelaideJohn1967 wrote:
Yes but if you make the trip at light speed there will be no real age difference. 4 years going 4 years back.....

Read up on "time dilation".  There will be a *huge* age difference.  The traveller will have aged 4 years (for each leg of the journey) but those of us on earth would have aged much much more.  If they travel at .99999c then we will have aged almost 900 years (1800 upon their return)

Lawrence Guy wrote:
Alcubierre warp drive might (huge emphasis on *might*) be possible, which would give us Star-Trek faster-than-light travel. Tricky part there is figuring out how to make something with negative mass.

Bussard ramscoops could get us up to 1/3 the speed of light. Combine that with genetic engineering to make people effectively immortal, or the old idea of generation ships, would mean we could colonize the galaxy in less than half a million years, which is a blink of the eye in cosmological terms.

If we could travel at near the speed of light without bursting into flame from all the particle collisions, relativistic time dilation would mean that passengers would experience the journey in a blink of the eye in human terms.

Why not Halo faster-than-light travel? I mean damn look at those UN warships in Halo jumping from the Epsilon Eridani system to the Sol System in a matter of days or to the edge of the galaxy in a matter of weeks with no time differences, Get with the times man   lol

Orestes  wrote:

Why not Halo faster-than-light travel? I mean damn look at those UN warships in Halo jumping from the Epsilon Eridani system to the Sol System in a matter of days or to the edge of the galaxy in a matter of weeks with no time differences, Get with the times man   lol

Because the Halo FTL drive is not a warp drive, while Star-Trek FTL is, and I was talking about physics that is at least acknowledged as possible by working physicists.

Lawrence Guy wrote:
Interestingly, all light that impinges on an object travelling at the speed of light will strike the exact front of the object. That is, from the POV of the object the entire universe appears to be a single really bright dot directly ahead of its direction of travel. This would continue to be true for objects travelling faster than the speed of light.

Very counter-intuitive! I would expect the forward light sources to be shifted up and past the blue into and past the X-ray realm of the spectrum while the stern would be shifted to longer and longer wavelengths. Both without the light-concentrating aspect they describe.

Lawrence Guy wrote:
An engineering implication of this is that, when building a light-speed or FTL ship, you only need to put your radiation shielding in the front of your vessel.

But what a shield it would have to be! Think of hitting atoms at light-speed...

Managing Light wrote:
Very counter-intuitive! I would expect the forward light sources to be shifted up and past the blue into and past the X-ray realm of the spectrum while the stern would be shifted to longer and longer wavelengths. Both without the light-concentrating aspect they describe.

Everything is blueshifted, but that means infrared and longer wavelengths could end up in the visible spectrum. The second set of pictures I posted incorporates the blueshifting, while the first doesn't.

Managing Light wrote:
But what a shield it would have to be! Think of hitting atoms at light-speed...

Forget atoms. Even photons are a problem. Remember, everything is blueshifted, so the photons are higher energy (x-ray and shorter wavelengths become more common). To make it worse, all the photons come at you from just one direction. On top of that, time dilation combined with high speed means you're dealing with a vastly increased photon flux (it's like running through a rainstorm - the faster you run, the more raindrops you hit per second). You're dealing with a tremendous amount of energy.

Lawrence Guy wrote:
You're dealing with a tremendous amount of energy.

Hey, no problem!  You managed to come up with the infinite amount of energy it took to get to light speed, just find a bit more...

Good Egg Productions wrote:
We haven't even explored the whole of this earth that we're living on.  There are parts of the bottom of the ocean that we've never seen or been to.

But hell... let's go see what's going on at Alpha Centauri.

Dude, this planet is boring and has been fucked up beyond repair, plus all this RAP music is enough to make anyone want to head for the stars!

The future is out there...somewhere!

Managing Light wrote:

Hey, no problem!  You managed to come up with the infinite amount of energy it took to get to light speed, just find a bit more...

Actually I didn't mention lightspeed travel. I suggested FTL using Alcubierre warp drive and 1/3 c with Bussard ramscoop. Then I speculated on particle collisions being problematic at near-lightspeed and posted some info on what things would look like at significant fractions of c.

/pedantic

MerrillMedia wrote:
The earth is flat.

You are living in the distant past!

Managing Light wrote:
Hey, no problem!  You managed to come up with the infinite amount of energy it took to get to light speed, just find a bit more...

Lawrence Guy wrote:
Actually I didn't mention lightspeed travel. I suggested FTL using Alcubierre warp drive and 1/3 c with Bussard ramscoop. Then I speculated on particle collisions being problematic at near-lightspeed and posted some info on what things would look like at significant fractions of c.

/pedantic

Sorry - bad wording.  The "You" meant the original scenario which suggested speeds of just under lightspeed, not you, Lawrence.

Robb Mann wrote:
If you're traveling at the speed of light and turn on your headlights, do they do anything?

Not sure about the "at the speed of light" situation, since that is a mathematical singularity.  But at near lightspeeds, your lights look normal to you if I remember my physics correctly.  'Course, I've slept since then...

Robb Mann wrote:
If you're traveling at the speed of light and turn on your headlights, do they do anything?

From the frame of reference of those on the ship.... I thought the answer was yes.  (see my post above)  However the post to link regarding how all star light appears to originate from ahead of the ship has me wondering if what I read on this subject years ago is accurate.

edit:  in my first post to this thread approximately half a page above I indicated what I believed to be the case at "nearly" the speed of light.  I agree with the post immediately above this one.  ....
Except that headlights appearing to be normal is probably a generalization.  When driving a car at high speeds in the dark, the driver has the sensation of outrunning the headlights.  This isn't because the car is approaching the speed of light but because the lights aren't bright enough to illuminate the road ahead far enough to compensate for driving faster than the speed limit in the dark.

TKPhotos wrote:
I'm still counting on the Infinite Improbability Drive. I have my cup of hot tea all ready to go...

The  Impossible Drive -- close enough

Nasa validates 'impossible' space drive
http://www.wired.co.uk/news/archive/201 … pace-drive

NASA microwave thruster deemed ‘impossible’ might actually work
http://www.techtimes.com/articles/12089 … y-work.htm

Michael Bots wrote:
The  Impossible Drive -- close enough

Nasa validates 'impossible' space drive
http://www.wired.co.uk/news/archive/201 … pace-drive

NASA microwave thruster deemed ‘impossible’ might actually work
http://www.techtimes.com/articles/12089 … y-work.htm

Interesting stuff.  No reaction mass.  I read about this last week.  I wasn't impressed by the "between 30 and 50 micronewtons of thrust".  My uninformed view was that it wouldn't be very useful in obtaining near light speed velocity, but who knows.

Toto Photo wrote:
At close to the speed of light, the human beings and ship would have close to infinite mass. I wonder what would happen to a human being at that mass?

From the point of view of the spaceship and the crew everything would seem normal because everything would be normal. From the point of view of the outside observer not only their mass would change, their size would change as well. If it was possible to observe it's not possible to observe the phenomenon but it's clear in the math and analogies help us to grasp the concept. I'm talking about the spaceship apparently getting larger as it approaches the speed of light. From the point of view of an outside observer. I read a book that provided a really cool example that helps to get an idea about the the relativistic effects from the point of view of an observer and the traveler. I'm going to try to make it as simple as possible.
There is an elevator (a lift). The elevator is outside the building and it's an opaque box with the exception of a lens on one side that projects image on the opposite wall of the elevator. It's a camera obscura moving up or down very fast. Now, let's imagine that light travels slowly, let's say walking speed. There are also two groups of observers, one inside the elevator and one outside. The outside group can only see the light hitting the lens. The inside group of observers can only see the light projected on the wall opposite the lens.
Let's hit floor 10 button and see what happens. The outside observers see the light hitting the lens all the way up to floor 10. Nothing exciting to see. The observers inside the elevator see the image projected by the lens. Nothing exiting to see either. But let's say one of the people inside the elevator is a smoker and exhales a puff of smoke making the light rays visible. If that happened the observers in the elevator would experience an illusion of the light coming in through the lens and then bending down before hitting the screen because the elevator is moving up as the light travels through it. In real science this is not possible to experieence directly, by human sense.
BTW, if you got through this long post and read it with understanding - congrats, this is what Einsteins' special theory of relativity in a nutshell.

London Fog wrote:
Not possible according to Einstein, and from his calculations we cannot make any object travel faster than 186,000 miles per sec?

But wait, what if we could make an object travel at 185,999 miles per sec, would that work? If so, we could reach Proxima Centauri in about 4 years, meet up with the locals and return back to earth in another 4.

Even then travelling that fast it would take us many hundreds of centuries to cover the entire width of our galaxy! So, it seems hopeless that even at this rate that we'll ever get anywhere near to finding out anything even remotely interesting in the Universe!

No, sorry. Not possible if our current understanding of basic physics is correct. To be clear, the reason why we can say that travel at speeds close to the speed of light is not possible isn't because we haven't understood some hidden laws of physics. The reason why we can say it's impossible is because the basic laws of nature do not allow it.
But if our understanding of the basic laws of nature is incorrect then, heck, who knows what is possible or impossible.