Post by: Michigander on August 17, 2007, 01:11:42 AM
By Nic Fleming, Science Correspondent
Last Updated: 12:01am BST 16/08/2007
A pair of German physicists claim to have broken the speed of light - an achievement that would undermine our entire understanding of space and time.
According to Einstein's special theory of relativity, it would require an infinite amount of energy to propel an object at more than 186,000 miles per second.
However, Dr Gunter Nimtz and Dr Alfons Stahlhofen, of the University of Koblenz, say they may have breached a key tenet of that theory.
The pair say they have conducted an experiment in which microwave photons - energetic packets of light - travelled "instantaneously" between a pair of prisms that had been moved up to 3ft apart.
Being able to travel faster than the speed of light would lead to a wide variety of bizarre consequences.
For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.
The scientists were investigating a phenomenon called quantum tunnelling, which allows sub-atomic particles to break apparently unbreakable laws.
Dr Nimtz told New Scientist magazine: "For the time being, this is the only violation of special relativity that I know of."
http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/08/16/scispeed116.xml
Post by: LadySmith on August 17, 2007, 01:25:57 AM
Although this part makes me a bit nervous:
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For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.
Post by: Manedwolf on August 17, 2007, 03:46:43 AM
BTW, Quantum Tunneling is incredibly cool, and one of those things that brings a grin once you understand it.
Quantum pair behavior is another one. Basically, if you separate a pair of quantum particles and move them any distance apart, if you reverse the spin on one, the spin on the other will flip as well...instantly, no matter how far away it is! This suggests that there's some thread below "our" perception of space that connects them. Which is incredibly cool.
I've also thought it could be used as a binary communicator across the solar system. If you assign one spin state as 1 and one as 0, every "flip" could be binary code in a sequence. Take a single pair or multiple pairs, separate them, put one half in a transceiver on earth, one half in one on a spaceship. Even out past the outer planets, you could have instant binary streams by rapid quantum flipping of one half of the pairs. Talk about never being out of reception range...anywhere in the universe!
Post by: K Frame on August 17, 2007, 03:50:16 AM
Anytime someone says there's donuts in the breakroom.
Post by: Fly320s on August 17, 2007, 04:57:20 AM
Sure, 186,000 miles per second sounds good, but that is an awful convenient number. Why not 186,211 miles per second? Are some energies faster while some are slower? Are x-rays faster than low-frequency radio waves? Has anyone measured light speed over an actual one mile course just to get a more accurate speed, like what is done for measuring vehicles?
Post by: wmenorr67 on August 17, 2007, 05:05:00 AM
Try this for some light reading. PUN intended.
Post by: Thor on August 17, 2007, 05:36:24 AM
Post by: Manedwolf on August 17, 2007, 05:49:27 AM
Quantum tunneling is going outside normal space, though. Or, more like beneath it. It's a dimension outside our perception. It's sort of a shortcut.
Post by: Len Budney on August 17, 2007, 05:52:50 AM
--Len.
Post by: Moondoggie on August 17, 2007, 06:16:26 AM
In other words, if we ever discover how to access this dimension of existence the possiblities are unimaginable. Time travel, instantaneous inter-galactic communication, extremely long range travel, possibly an entirely new form of existence.
Wow.
Post by: Manedwolf on August 17, 2007, 06:18:36 AM
Because the science and all the data point to the very real possibility that yes, perhaps one day, moving from point to point in real space by doing so in a quantum jump outside of real space is possible. We just need to figure out how not to be squished to subatomic particles in the process. Try looking up string theory. That's pretty awe-inspiring, too.
Post by: Michigander on August 17, 2007, 07:37:27 AM
http://phys.educ.ksu.edu/vqm/html/qtunneling.html
Einstein stated that time is an illusion, correct?
We know that time does not exist without space, right?
Hence we have space-time.
Therefore our "space-time" is an illusion, wouldn't it follow?
So this "tunneling" is operating outside our space-time illusion, yes?
I dunno!
Post by: Nitrogen on August 17, 2007, 11:50:17 AM
Post by: Tallpine on August 17, 2007, 01:18:58 PM
Imagine driving your new Toyota Quantum Leap to work ... you could sleep in till noon, and still get to work at 8am
I'd like to go back in time to some of my more foolish moments / missed opportunities
Post by: drewtam on August 17, 2007, 01:29:21 PM
Gamma rays, X-rays to light to radio waves, are all photons, packets of light. The only difference is the frequency on the FM dial. They all have the same speed.
186,000mps is for light through a vacuum. That doesn't say anything about light through a medium. In 99.9% of the cases, light through a medium is slower. But this is the second case I know of, where light through a medium is faster than the vacuum (space).
Particles going through a medium can go faster than light through the medium. Thats why the nuclear plant's swimming pools glow that awesome blue.
http://www.physlink.com/Education/AskExperts/ae219.cfm?CFID=20169337&CFTOKEN=44224634
Drew
Post by: Mabs2 on August 17, 2007, 04:24:08 PM
What moves at the speed of light? Light does.
So I'm going to go stuff a bunch of light bulbs and batteries in my car's gas tank and let you guys know what happens.
If that fails, I'm going to make a sail out of a bed sheet and put a spotlight behind it.
Post by: Manedwolf on August 17, 2007, 05:04:37 PM
If that fails, I'm going to make a sail out of a bed sheet and put a spotlight behind it.
You can do that in space with a sail several hundred miles wide, to catch the solar wind...but it'll take you a few thousand years to get up to any speed approaching C.
Post by: Tallpine on August 17, 2007, 06:14:18 PM
Post by: Perd Hapley on August 17, 2007, 08:56:49 PM
So I'm going to go stuff a bunch of light bulbs and batteries in my car's gas tank and let you guys know what happens. If that fails, I'm going to make a sail out of a bed sheet and put a spotlight behind it.
OK, I'm just going to go ahead and say that that's not going to work. Probably.
Post by: Antibubba on August 17, 2007, 10:44:43 PM
Being a Democratic Congress they'll believe that the mere passing of that law will prevent further violations.
Post by: Fly320s on August 18, 2007, 03:22:36 AM
But can you tack upwind
Sorry, no tackiness allowed, but you may slingshot yourself around the nearest gravitational body if you choose.
Post by: Tallpine on August 18, 2007, 04:54:11 AM
Post by: wmenorr67 on August 18, 2007, 05:32:21 AM
Post by: Sindawe on August 18, 2007, 05:34:52 AM
Where the heck is the freaking Jumpgate/Stargate/Warpdrive?
Post by: drewtam on August 18, 2007, 06:52:49 AM
In my worthless opinion, we need to dump the useless fusion research and mars travel and spend all that money on the physics of dimensions and faster than light travel.
Drew
Post by: Perd Hapley on August 18, 2007, 06:57:23 AM
Post by: Manedwolf on August 18, 2007, 06:58:47 AM
People use this to watch the famous events of human history and even religions as eyewitnesses, to see the truth. And society nearly collapses as a result of that, absolute and complete upheaval as the truth of so many things is revealed.
As for terraforming, one of the most viable schemes is to dump engineered organisms in massive quantities into atmospheres that are thick enough, but not anything we can use. Like, say, Titan. Or Venus, if something could be found that'd deal with the heat and sulfuric acid. Venus would be ideal for expansion, it's just that right now, it's covered with a dense atmosphere of superheated corrosives (932 degrees F) that would simultaneously crush, burn and dissolve you. A lot of people have described Venus as an Earth that just didn't work. It's similar in size and tectonically active, but a whole lot of carbon would need to be sequestered to cool it down. Others have suggested mining reflective minerals from the moon and scattering them around the planet to reflect some sunlight. In any case, it's so close to Earth's size that it's .9 G, making it absolutely ideal in terms of gravity. You'd only weigh 10% less, which would require no adaptation.
What Venus could look like, terraformed:
Mars is also a possibility, but it would need to be heated significantly, and have a much thicker atmosphere.
Post by: Perd Hapley on August 18, 2007, 07:31:57 AM
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You'd only weigh 10% less
After being crushed, burned and dissolved? I bet you'd way quite a bit less than that.
Post by: tyme on August 18, 2007, 08:14:41 AM
http://arstechnica.com/news.ars/post/20070816-faster-than-the-speed-of-light-no-i-dont-think-so.html
Bell's Speakable and Unspeakable in QM...
http://kempg2rlecgwrosm.onion/ebooks/physics/Bell,%20J.%20-%20Speakable%20and%20Unspeakable%20In%20Quantum%20Mechanics%20(Cornell-1987).djvu
Post by: Mabs2 on August 18, 2007, 12:04:33 PM
If that fails, I'm going to make a sail out of a bed sheet and put a spotlight behind it.
You can do that in space with a sail several hundred miles wide, to catch the solar wind...but it'll take you a few thousand years to get up to any speed approaching C.
Yes I'm the person who invented this theory a billion years ago.
My prototype just made it to 88MPH.
Post by: S. Williamson on August 20, 2007, 08:39:33 PM
Edit: Nevermind. Got to thinking about the laws of conservation of energy and just before my mind exploded I remembered why. Something to do with light = energy, energy is needed to propel, and since there's no such thing as perpetual motion there's no conventional way it can be done.
It'd suck, though, to walk in on your wife cheating on you with yourself from a couple hours ago.
Post by: LadySmith on August 21, 2007, 03:26:25 AM
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It'd suck, though, to walk in on your wife cheating on you with yourself from a couple hours ago.
That made my head hurt. 
Post by: AJ Dual on August 21, 2007, 08:28:39 AM
I could never figure out why the speed of light was supposed to be impossible to breach. It's just a speed, ain't it?
Edit: Nevermind. Got to thinking about the laws of conservation of energy and just before my mind exploded I remembered why. Something to do with light = energy, energy is needed to propel, and since there's no such thing as perpetual motion there's no conventional way it can be done.
It'd suck, though, to walk in on your wife cheating on you with yourself from a couple hours ago.
Edit: Nevermind. Got to thinking about the laws of conservation of energy and just before my mind exploded I remembered why. Something to do with light = energy, energy is needed to propel, and since there's no such thing as perpetual motion there's no conventional way it can be done.
It'd suck, though, to walk in on your wife cheating on you with yourself from a couple hours ago.
Yeah. Photons are massless, they're all "E" and no "m". So the instant you create one, it squirts off like a watermellon seed at c, but it can't go any faster than that (or slower, in a vacuum at least, either.)
If you were on a space ship travelling at 99.9% of c and stood on it's nose and shined a flashlight in front of you, the photons would still look to be travelling away from you at c, and to an observer in a stationary reference frame, the photons you shot off the nose of your ship would also arrive at c as well, but they'd express the difference in potential energy through a higher frequency, and the light would be severely blue-shifted, maybe even x-rays or into the gamma.
And yes, no material object can ever be accellerated to c either, just very close. Because a material object has mass, instead of how a photon emitted from relatavistic moving object gains or loses energy through frequency respective to a stationary reference frame, a material object gains more mass.
So as you start approaching exponentialy closer to c, you mass more, and it takes a commensurately larger energy increase to accelerate you further, and it keeps on increasing at an exponential rate, to the point that after 99.9999----9% whatever, of c there isn't enough energy in all the Universe to push a physical massed object, no matter how small to 100% of c, much less beyond it.
There are potential loopholes. While mass can't move at c or beyond it, it's been demonstrated, at least mathematically, that pieces of space-time themselves can be moved about at rates faster than c from the perspective of a stationary reference frame. Physicist Miguel Alcubierre postulated that a region of space with a gravity well in front of it, and a negative anti-gravity hill behind it could carry a ship or mass riding motionless within a piece of space-time along at speeds greater than c.
However, there are nearly insurmountable physics and engineering obstacles to producing gravity wells, much less anti-gravity "hills" using projected energy of some kind that are probably almost as bad as simply trying to garner the energy to push mass to c the "conventional" way.
Post by: mtnbkr on August 21, 2007, 08:42:17 AM
Chris
Post by: Manedwolf on August 21, 2007, 08:48:49 AM
That if you went out on a round trip at speeds approaching C, while only a year or so might pass for you, decades would have passed on earth. Time is not a constant.
Post by: zahc on August 21, 2007, 10:27:11 AM
Post by: Tallpine on August 21, 2007, 11:09:58 AM
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If you were on a space ship travelling at 99.9% of c and stood on it's nose and shined a flashlight in front of you, the photons would still look to be travelling away from you at c, and to an observer in a stationary reference frame, the photons you shot off the nose of your ship would also arrive at c as well, but they'd express the difference in potential energy through a higher frequency, and the light would be severely blue-shifted, maybe even x-rays or into the gamma.
That's just plain hard to imagine - it seems like the light from the flashlight would have to be moving at nearly twice the speed of light. For the light to be traveling at c relative to the spaceship and relative to a stationary object at the same time, then "space" could not be a fixed size (or maybe it's the time that is shifting?).
Also, if you were traveling somewhere nearly c, and sent a radio message back to earth, it seems like the message would never get back there.
Post by: Brad Johnson on August 21, 2007, 11:54:07 AM
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That's just plain hard to imagine - it seems like the light from the flashlight would have to be moving at nearly twice the speed of light.
And people wonder why Einstein's hair looked like that...
Brad
Post by: Tallpine on August 21, 2007, 12:29:21 PM
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And people wonder why Einstein's hair looked like that...
I heard that he never learned to tie his shoes, either
Post by: wmenorr67 on August 21, 2007, 04:20:06 PM
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And people wonder why Einstein's hair looked like that...
I heard that he never learned to tie his shoes, either
Why should he. He invented velcro.
Just didn't want the rest of the world to know. Got the idea from his hair.
Post by: drewtam on August 21, 2007, 04:24:47 PM
Quantum entanglement demonstrates that information can travel faster than the speed of light. I'm still not quite up on what the ramifications of that one are.
My reading suggest thats not true. That if you force one to change spin that it breaks the entanglement. The spin change is random but coupled somehow. So information can be passed since you can't control the spin change. I was disappointed when I read it.
Drew
Post by: Tallpine on August 21, 2007, 05:00:14 PM
Quote
If you were on a space ship travelling at 99.9% of c and stood on it's nose and shined a flashlight in front of you, the photons would still look to be travelling away from you at c, and to an observer in a stationary reference frame, the photons you shot off the nose of your ship would also arrive at c as well
Upon further reflection, I think I'm getting the hang of this.
Suppose I am in that space ship traveling at 0.999c. But time has slowed down from my perspective, and since speed is expressed as distance/time, then I'm not really travelling that fast at all. (maybe I'm not even moving?) So when I turn the headlights on or key up the radio, the light/radio waves travel away from me at c just like I was sitting still, which maybe I am.
Or maybe not....
Post by: illinoisdeerhunter on August 21, 2007, 05:42:00 PM
Post by: Hawkmoon on August 21, 2007, 06:13:58 PM
The part I don't quite grok, though, is the statement that if an astronaut traveled faster than the speed of light he would arrive before he left. That doesn't make sense.
Suppose our intrepid hero is at point 'A' and that point 'A' is 558,000 feet from point 'B.' (558,000 conveniently being 186,000 x 3). Suppose our hero departs point 'A' and, through an undiscussed trick of physics is able to accelerate instantaneously to a velocity of 200,000 feet per second -- a mere 7.5% faster than the speed of light, but faster, nonetheless.
So the moment of departure is 0:00:00. 558,000 feet divided by 200,000 fps says to my tiny brain that the trip requires 2.79 seconds, making the time of arrival (assuming equally instantaneous deceleration at point 'B') 0:00:02.79. Our hero has NOT arrived before he departed. However, if an observer at point 'B' had an optical viewer capable of seeing point 'A,' the traveler would arrive at point 'B' before the observer saw him depart point 'A.'
Post by: S. Williamson on August 21, 2007, 11:47:20 PM
/nerd
Post by: AJ Dual on August 22, 2007, 06:33:04 AM
Quantum entanglement demonstrates that information can travel faster than the speed of light. I'm still not quite up on what the ramifications of that one are.
My crude understanding of quantum entanglment experiments is that no one has been able to prove that you can transmit meaningful information through quantum entanglement faster than light.
It's not like researchers have split a particle of some kind, then put one half in a box and shipped it to Japan, then wiggled the half that stayed in the lab to see if the one in Japan wiggled the same, making a "quantum modem". It doesn't work like that. (How I wish it did!) And at the scale of these lab experiments, the results themselves are measured at the speed of light or less, and interpreted by the researchers brains at a much slower speed than that. So no one has yet to transmit meaningful data faster than light and violate Ensteinean causality on the macro-scale.
The quantum entanglement phenomena is demonstrated via beams of light that are split producing quantum entangled photon-pairs. They then block or polarize one half of the beam, and the other does the same thing, instantly. That's spooky-cool as all hell. And they can measure it in the lab in such a way as to prove that it happens instantly. It's not as if researchers have figured out how to produce two quantum entangled chunks of matter that can then be placed into two separate communication devices that can be placed anywhere in the Universe.
So with the quantum entangled phenomena, if you wanted to send a message to Alpha Centauri, the quantum entangled beam would still take 4.3 years to get there and you've gained nothing beyond the distance of a few feet that the "local" beam was changed at the Earth communication station. So if the beam is split at Earth, and one is aimed at Alpha Centauri, and then the Earth beam gets modulated say 10 feet away from it's splitting point, the beam on it's way to Alpha Centauri will be modulated within the first 10 feet of it's travel too.
I suppose you could try to "stall" the Earth beam within a convoluted 4.3 light-year long fiber optic cable before modulating it, but the speed of light in matter is different than it is in a vacuum. Of course, trying to punch a single beam through a 4.3 light-year long piece of glass would be impossible. You'd need repeaters, and then the quantum entangled light would not be the same as the beam shot at Alpha Centauri once it hit the first optical repeater.
The quantum effect might be useful someday on the micro scale in optical and quantum computing, but I think it's unlikely that you'll be able to transmit information using quantum entanglement faster than light on the macro scale. I hope I'm wrong, FTL communications would revolutionize even things right here on Earth and the satellites that orbit it.
Beyond the weirdness of General and Special Relativity, and Quantum Mechanics, is that every time we find a "loophole", like quantum entanglement, there's some other compensating factor that suggests that the loophole can never be exploited in any meaningful way. It's like the Ten Commandments are written into something far more permanent than stone, the fabric of existence itself for us to find. These are God's laws, and the kinds of things that have pushed me back from agnosticism. At this point one starts running into discussions of the strong and weak Anthropomorphic principle which is a mind-bending discussion of it's own right.
Post by: Manedwolf on August 22, 2007, 07:01:51 AM
Hence the Picard maneuver.
/nerd
/nerd
That's the only time that show ever bothered with that.
And I prefer the Adama Maneuver.
Far more "pair of big brass ones"... http://www.youtube.com/watch?v=x52joWFK86I
Post by: AJ Dual on August 22, 2007, 11:17:08 AM
Hence the Picard maneuver.
/nerd
/nerd
That's the only time that show ever bothered with that.
And I prefer the Adama Maneuver.
Far more "pair of big brass ones"... http://www.youtube.com/watch?v=x52joWFK86I
That was indeed one of the best moments of small-screen Sci-Fi ever.
And it's simply because the writers had the vision to explore some of the broader ramifications of their fictional technologies and true desperation scenarios.
Unlike Star Trek, which tends towards focusing on the minutiae of those technologies, and producing Ex-Machina solutions far too often.
Post by: tyme on August 22, 2007, 12:48:07 PM
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Beyond the weirdness of General and Special Relativity, and Quantum Mechanics, is that every time we find a "loophole", like quantum entanglement, there's some other compensating factor that suggests that the loophole can never be exploited in any meaningful way. It's like the Ten Commandments are written into something far more permanent than stone, the fabric of existence itself for us to find.
I can imagine someone a few hundred years ago making just such a claim about finding a loophole that would enable a metal shell with hundreds of people to fly over the oceans.
Just because everything we've seen so far indicates that current theories of relativity and QM are fairly solid, that doesn't mean some crazy physicist or patent clerk won't put a metaphorical propeller on a metaphorical wing and blow those theories to pieces.
It upsets me greatly whenever someone like you alludes to some ultimate truth as the reason why physics hasn't advanced in some area. What is the use of that kind of thinking, besides discouraging people from pursuing research in those areas? Even if we've hit the wall, we can never know that for sure, and unless people constantly try to push the wall, we don't have even a modest assurance that our current physical theories are sound.
Post by: Brad Johnson on August 22, 2007, 12:52:59 PM
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that doesn't mean some crazy physicist won't put a metaphorical propeller on a metaphorical wing and blow those theories to pieces.
I'll see your metaphors and raise you a simile.
Brad
Post by: Perd Hapley on August 22, 2007, 02:04:43 PM
Post by: AJ Dual on August 22, 2007, 04:48:32 PM
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Beyond the weirdness of General and Special Relativity, and Quantum Mechanics, is that every time we find a "loophole", like quantum entanglement, there's some other compensating factor that suggests that the loophole can never be exploited in any meaningful way. It's like the Ten Commandments are written into something far more permanent than stone, the fabric of existence itself for us to find.
I can imagine someone a few hundred years ago making just such a claim about finding a loophole that would enable a metal shell with hundreds of people to fly over the oceans.
Just because everything we've seen so far indicates that current theories of relativity and QM are fairly solid, that doesn't mean some crazy physicist or patent clerk won't put a metaphorical propeller on a metaphorical wing and blow those theories to pieces.
It upsets me greatly whenever someone like you alludes to some ultimate truth as the reason why physics hasn't advanced in some area. What is the use of that kind of thinking, besides discouraging people from pursuing research in those areas? Even if we've hit the wall, we can never know that for sure, and unless people constantly try to push the wall, we don't have even a modest assurance that our current physical theories are sound.
I can only conclude you missed the parts where I mentioned hoping I was wrong about that more than once.
So please stop trying to lump me in with Luddites of 100 years ago. I would love nothing better than for there to be a "trick" to FTL communication, much less travel. Growing up as a hard-core SF fan and seeing visions of our future slip away as I learned more and more about physics and relativity was at best, dissapointing, and at worst, heartbreaking.
The Western Civilization mindset that perhaps has some of the needed vision, and the best chance to develop the needed technology unfortunately has a hard time thinking (By "thinking", I mean politically and meaningfully as a group, not just individual dreamers and pundits) more than a decade in advance. And the Eastern mindsets that can think in terms of the centuries only seem to do so with a view towards blood-feuds and religious zealotry.
When we can't even plan for 50 years into the future, journeys of hundreds, if not thousands, of years are unthinkable, whether or not we develop the technology. No one may bother. So I sincerely hope there are loopholes in the fundamental laws of the universe that will give us goals that are attainable in both time and space, otherwise I suspect mankind will go extinct.
I am simply commenting that as we do discover potential loopholes, to date there seems to be a chilling symmetry with very good fundamental constraints on why we can't use them in any meaningful way.
Post by: drewtam on August 22, 2007, 05:29:54 PM
I would love nothing better than for there to be a "trick" to FTL communication, much less travel. Growing up as a hard-core SF fan and seeing visions of our future slip away as I learned more and more about physics and relativity was at best, dissapointing, and at worst, heartbreaking.
My sentiments, exactly put. My hopes lie in greater exploration and understanding of the graviton (if it exists) and its properties and how we can control it (if possible).
Drew
Post by: Perd Hapley on August 22, 2007, 05:32:43 PM
Post by: Tallpine on August 22, 2007, 05:47:13 PM
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Why do we need deep-space travel? Not that I'm against it, but why would we need to go anywhere?
1) overpopulation
2) old Sol is going to burn out in another couple billion years
3) Why not? We found and settled the New World, and explored the Polar regions. What else is there to do between crops?
Post by: tyme on August 22, 2007, 05:54:48 PM
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I am simply commenting that as we do discover potential loopholes, to date there seems to be a chilling symmetry with very good fundamental constraints on why we can't use them in any meaningful way.
I am simply saying that that line of thinking dismisses a long history of technological plateaus and cliffs, after which humans have climbed up higher than before. Do you think people who questioned the ability of heaving things to fly didn't feel exactly the same way about it that we feel about holes in GR or QM? I doubt it. Just because we have made tremendous technological advancements recently doesn't mean we're any better equipped to judge when our working theories are more than an approximation that ceases to hold if someone merely comes up with the right trick to get around them.
Post by: AJ Dual on August 23, 2007, 08:46:35 AM
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Why do we need deep-space travel? Not that I'm against it, but why would we need to go anywhere?
1) overpopulation
2) old Sol is going to burn out in another couple billion years
3) Why not? We found and settled the New World, and explored the Polar regions. What else is there to do between crops?
1. We'd never be able to export population off the planet fast enough to solve overpopulation that way. Plus even if we could, there's the issues of who would go, and who stays. (Easier, I suppose if Earth were so miserable the decision to leave was a no-brainer.) However, space resources (Asteroid metals, Geostationary solar power, moving "dirty" industries off-planet, etc.) could provide a first-world standard of living to everyone on Earth, which seems to be the only proven way to stem population growth we've seen to date.
2. If we should survive until the sun leaves the main sequence, and there is some continuity of humanity that still survives until that time, we'll probably either possess the engineering prowess to deal with it, or we'll be so far evolved that such things won't harm us. One could argue a cyclical civilization, and "falls" or dark ages, but if that happens humanity will eventually succumb to climate change, disease, supervolcanisim, asteroid/comet impact, technological "oopses", or war long before then, well within a million years, or less. So if we survive until the sun itself starts changing, humanity (or what passes for it by then) by default will be able to deal with it.
3. Very true, some of the best success stories in our history are when we were challenged with "somewhere to go" and something to do. And unlike the Earth, we're much less likely to repeat the tragedies that accompanied the era of exploration. (i.e. "native populations") Space is huge, other sentient species, even if common, are still widely separated in both space and time. There is plenty of "elsewhere" to go to. And assuming we've mastered robust at-will interstellar travel, from a technological standpoint there is very little we couldn't produce ourselves or synthesize after only minor sampling and study. So even if our morality did not evolve, simple economics makes the Universe a very unlikely place for either conflict or exploitive colonization.
I disagree with some of the details, but in the general thrust of his arguments, Tallpine is right. If we don't expand off of Earth, humanity will go extinct. It's possible we could develop sufficient technology AND social organization to live on Earth indefinitely in peace and safety, but the historical record on the human scale does not make me very confident, and neither does the natural disaster record on the geological scale.
We are not "special". Forces beyond our control could remove humanity in an eye-blink. The mitochondrial DNA record of humanity's maternal line already indicates that humanity has already faced extinction several times, we've been winnowed down to a mere 20 or 30 fertile females in the past more than once.
As long as we are on Earth, and only Earth, all of our eggs metaphorically, and literally, are in one basket.
Post by: Manedwolf on August 23, 2007, 08:50:29 AM
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As long as we are on Earth, and only Earth, all of our eggs metaphorically, and literally, are in one basket.
And nature proves that no animal that just sits in its birth-nest and soils it will survive for long.
At some point, you need to leave the nest and head outwards.
Post by: Tallpine on August 23, 2007, 09:03:25 AM
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We'd never be able to export population off the planet fast enough to solve overpopulation that way.
Sure we can - we just "beam" them out to the extra-stellar colonies or wherever.
Or don't you think that by the time we figure out beaming(wormhole/FTL/whatever) that we couldn't build a machine that did more than one person at a time?
Not for me though ... I'd just as soon spend my remaining years among the pines, rimrocks, and prairies.
(We will stay where the rivers run through the range and the sky, buckskin and blue ...)
Post by: Manedwolf on August 23, 2007, 09:24:26 AM
Now, THAT is a place that's worthy of the name Vulcan or Hephaestus...and that'd be something I'd want to see in person.
While well-insulated, of course.
Post by: Tallpine on August 23, 2007, 12:28:03 PM
Quote
One of the possible planets they've discovered around a nearby star is seemingly hot enough, and has a probable atmospheric composition such that it might well have clouds of superheated metal vapor and rain drops of molten iron.
Global warming caused by SUVs no doubt ...
Post by: Balog on August 23, 2007, 01:27:39 PM
Quote from: drewtam
We could strip mine all the useless planets, terra-form the better ones.
Best. Plan. Ever.
Post by: drewtam on August 23, 2007, 02:34:53 PM
Read here for a more indepth explanation.
http://www-formal.stanford.edu/jmc/progress/population.html
2. Who cares what happens in a billion years (literally, a billion years).
3. Its nice to travel. It is a romantic notion to "walk among the stars" (name that tv series)
Another good reason:
4. Theres gold in them hills. With a few million planets in our galaxy, I'm sure we could all become wealthy from the natural resources.
5. Personal freedom. If there is enough room for all of us to have our own continent, what reason would there be for crime or police or governments? How would government survive. If they try to oppress you, leave well beyond the borders of where they can find you.
Drew
Post by: Manedwolf on August 23, 2007, 04:02:06 PM
If they try to oppress you, leave well beyond the borders of where they can find you.
Drew
Drew
Take my love, take my land
Take me where I cannot stand
I don't care, I'm still free
You can't take the sky from me
Take me out to the black
Tell them I ain't comin' back
Burn the land and boil the sea
You can't take the sky from me
Post by: Harold Tuttle on August 24, 2007, 07:32:20 AM
Quote
May I pass along my congratulations for your great interdimensional breakthrough.
I am sure, in the miserable annals of the Earth, you will be duly enshrined.
I am sure, in the miserable annals of the Earth, you will be duly enshrined.
Post by: Gewehr98 on August 24, 2007, 08:35:49 AM
(Gawd, I love that movie!)
Post by: CAnnoneer on September 22, 2007, 09:42:59 PM
What is necessary is creativity and innovative inquisitive thinking. Incrementalism would not produce revolutionary breakthroughs, because it is inherently based on old conceptions of how the world works.
For example, there are very good-looking arguments that could have been (and probably were) made before the steam engine, to the effect that transportation speed and capacity are ultimately limited by horsepower. Since it is not practical to yoke 500 horses to the same cart, cargo size is limited. More horses would also still travel at best at the maximal speed of any horse, and therefore any landbased transportation is inherently limited by the speed of the fastest horse. Such arguments are literally right, but their broader conclusions are based on the underlying assumption is that there are no other physical means of harnessing energy and generating mechanical work. The steam engine and later the internal combustion engines broke both cargo and speed limitations without violating the fundamental physical laws. Moreover, the study of electromagnetism provided yet other means of locomotion, among many other things.
In the same way, we should continue fundamental experimentation to look for "loopholes" if you will, filling gaps and discovering breaches of our current understanding, as well as innovative engineering solutions to harness what is already known in the fundamental physical perspective.
If there is a difference with respect to the past, it is that in most areas of experimental science, it seems it is no longer possible for a loner in a basement to discover something hugely significant by himself, because the equipment necessary for the measurements is generally far more elaborate and expensive, and takes many more manyears to design, build, assemble, test, and use. But all of that are funding, cultural, and organization issues, rather than fundamental science limitations.
One of the examples I can think of is controlled fusion. The field has been around for many decades now, but it is not aggressively funded and a lot of their time and effort is based on incrementalism in small improvements to existing techniques and geometries. That is why they appear stuck with being unable to sustain and control the fusion reaction, and so they end up investing more energy than they get out due to fusion. The obvious solution to me is completely new ideas about ignition, containment, scales, and materials involved, rather than crawling incrementally to no visible advantage. Moreover, we know that fusion works (we see it every day), so there isn't even a fundamental physical secret to uncover; instead the problems seems mostly an engineering one.
Post by: S. Williamson on September 22, 2007, 09:59:03 PM
...did it really take you a month to write that?
Post by: Mabs2 on September 23, 2007, 03:48:23 PM
Well then beam me up, Scotty!
Although this part makes me a bit nervous:
Yea, I really don't understand this stuff.Although this part makes me a bit nervous:
Quote
For instance, an astronaut moving faster than it would theoretically arrive at a destination before leaving.
With all the distances involved in space, light seems pretty darn slow...
Wtf goes on that makes this crazy stuff happen? D:
Post by: Nick1911 on September 24, 2007, 04:30:41 AM
Post by: Mabs2 on September 24, 2007, 06:58:20 AM
Old guys are funny.
Post by: CAnnoneer on September 24, 2007, 10:21:55 AM
CAnnoneer, posts like yours are why I read APS.
Thanks, I appreciate it. I share the sentiment and motivation.
Post by: tyme on September 24, 2007, 11:15:30 PM
Quote from: CAnnoneer
Moreover, we know that fusion works (we see it every day), so there isn't even a fundamental physical secret to uncover; instead the problems seems mostly an engineering one.
The kind of fusion we see every day is not the same fusion reaction attempted in terrestrial fusion reactors, nor are there the same fuel constraints as there are on Earth. Notably, hydrogen-burning stars use fusion reactions that are more difficult to achieve; we have to look for easy fusion reactions, which at the moment means deuterium-tritium. Unfortunately, tritium has to be produced by fission of lithium-6. Not only is fission is here to stay, but lithium-6 is quite expensive.
Here's what hydrogen-burning stars do: http://en.wikipedia.org/wiki/Proton-proton_chain_reaction
So we have to manufacture tritium (from lithium-6) ourselves (at least for deuterium-tritium fusion used in JET and planned for ITER and the far-future DEMO reactor).
A success with ITER will not address the costs of maintaining/fueling a real fusion power plant, nor the cost or energy requirements for fueling enough fusion plants to supply most of the world's electricity.
http://math.temple.edu/~wds/homepage/fusion.boondog
Based on that very detailed analysis, D-T fusion, even if it works, is not economical, and suffers from more resource constraints (supply of lithium-6) than fission. We should be funding more general nuclear, particle, and QM physics research in an effort to make D-D or ideally B-H fusion feasible.
Post by: LadySmith on September 25, 2007, 12:37:40 AM
I'm looking forward to the day that I can go back to make sure I unplugged the iron before I even leave home.
Post by: AJ Dual on September 25, 2007, 06:00:10 AM
Quote from: CAnnoneer
Moreover, we know that fusion works (we see it every day), so there isn't even a fundamental physical secret to uncover; instead the problems seems mostly an engineering one.
http://math.temple.edu/~wds/homepage/fusion.boondog
Based on that very detailed analysis, D-T fusion, even if it works, is not economical, and suffers from more resource constraints (supply of lithium-6) than fission. We should be funding more general nuclear, particle, and QM physics research in an effort to make D-D or ideally B-H fusion feasible.
I agree, or perhaps He3 fusion using He3 extracted from the lunar regolith. (which would also have the advantage of jump-starting space infrastructure industry in general..)
I've sen some stuff on the net about B-H "garage fusion", but everything I saw had the stink of the "perpetual motion guys" on it. Any semi laman links to serious B-H fusion research?
Post by: CAnnoneer on September 25, 2007, 08:49:29 AM
During WW2, the Germans essentially convinced themselves that they could not produce the A-bomb, because Heisenberg calculated that under certain assumptions the critical mass would be the size of a very large beachball. "Obviously then", not enough could be purified in meaningful time. In addition, Hitler spent the bulk of research money on the V-2 project instead of the A-bomb. Finally, because of scarcity of funds and political rivalry, there were actually several separate groups working on the same A-bomb project without collaboration.
Except, Heisenberg's calculation was right only within the constraints of the assumptions he made, so the general conclusion was ultimately incorrect. The Manhattan Project calculated the critical mass to be the size of a golf ball, and they were right under their own assumptions, arriving at the respectively different conclusion. Also, many times the funds were invested in a large, unified project where enrichment was done on gigantic industrial scale. Oppenheimer got the bomb and Heisenberg did not.
For all the bile boondog has for the plasma physics community (probably a failed gradstudent), he essentially recongizes the above albeit tacitly and circuitously. Why is it that those workers concentrate on incrementalism? Because of stupidity, incompetence, greed, or dishonesty? If they really wanted to make money, they would not be in science, and considering how much intellectual effort and training and work is involved in getting where they are, they certainly are no fools. In fact the only ones left in that field are the believers, because with the meagerness of funding, it certainly is not a good career move.
The reality is that the underlying problem is the structure and amount of funding, i.e. ultimately fedgov policy. They bellyache every time the gas goes up and throw a bit of money that way to shut up critics, and then it is business as usual. The field has been left for many years on barely subsistence level, and that is why most workers leave it after they complete the PhD. There is a simple analogy - if you are starving, you tend to conserve your strength, you don't take risks, you don't run around, you severely limit what you do, you mostly drag your feet and go for small, easy prey, because going after the big prey will likely kill you. You must show some progress each year, to get the next leg of funding. That means you cannot pursue high-risk high-reward ideas, because it would take so much time to first good results that you will be forced out of funding by then, by incrementalists. And that is assuming the little morsel you got this year can actually cover the entry cost of the big risk even if you went crazy and did decide to go for it.
That's the reality. It ultimately stems from the fact that gov policy on research is strongly influenced if not completely dictated by beancounters, essentially accountants and lawyers, who have a very weak idea of the technical challenges and the resulting imperatives for efficient policy-making. The other half of the issue is that elected officials want to do things that make them good NOW, not in 10 years. Therefore, only a few eccentrics are truly interested in long-term policies, which might reach fruition long after the expiration of their mandate. Add to that environmentalists with a knee-jerk reaction to nuclear power of any sort, even if it is not fission, as well as "social progressives" who would say the money would be better spent on their pet social project handouts, and finally sensation-hungry media who think that everything in nature must move at the speed of their 24-hour news cycle, or it is a "quagmire".
Post by: Phyphor on September 25, 2007, 10:20:51 AM
http://discaircraft.greyfalcon.us/DIE%20GLOCKE.htm
Post by: AJ Dual on September 25, 2007, 10:58:29 AM
That and the Germans were too busy ringing "The Bell (Die Glocke) "
http://discaircraft.greyfalcon.us/DIE%20GLOCKE.htm
http://discaircraft.greyfalcon.us/DIE%20GLOCKE.htm
I'm sorry, but I looked at the rest of that site...
The world production of Bauxite ore for Aluminum is not sufficient to make the required headgear...