this is the problem. i dont know how many of you ahve worked with CS doctorates, but they are some of the most obtuse people i know, and dont generally have any idea what it is the average person wants or needs. (which, imho is what drives this industry)
For most ground level practical work, you're probably correct. But the people that make real waves are the super-smart PhD computer scientists and mathematicians. Think of Google, Alan Turing, Xerox Parc, etc.
Blasting something up with lasers is less expensive than using mechanical coupling. Though I agree, putting solar panels on the cars to power them is sort of silly. I'd run parallel rails up the beanstalk and let the cars tap the electricity.
There's something else you've overlooked: A car coming DOWN can use regenerative braking and feed power INTO the rails. If we're going to be mining for metals in space, we might wind up generating more electricity from the cars coming down than we'd spend in bringing cars UP. Net profit, even before selling the metals.
You can't use parellel rails. These cars would require thousands of amps, which is too much to carry in a poorly conducting carbon fiber ribbon which weighs one kilogram per kilometer. You'd need a big thick copper cable, which is unfeasable for obvious reasons. Thus, the energy must be beamed up by laser.
To low earth orbit, yes. But remember that the cable is stationary above the Earth, so one orbit is exactly 24 hours (it's more like 90 minutes in LEO). Thus, to move fast enough to actually be in orbit, rather than just falling back down to Earth, the elevator must go all the way to geosynchronous orbit, which is more like 24,000 miles out.
Ignition isn't Q=1. Breakeven is Q=1. To be economical, a D-T reactor's going to have to hit Q ~= 20; that is, 20 times as much energy coming out as you're putting in.
Ignition is what you get when the reaction sustains itself with no input energy at all; Q = infinity, basically.
although complex, if there IS a net gain, couldn't that be used to keep the reaction going, even without ignition?
That's pretty much the definition of ignition. It turns out you need a lot of net energy to keep everything at the proper temperature. So Q=1 is not nearly sufficient.
Magnetic containment. This isn't like fission reactions. There isn't a "pile." Just a couple of grams of non-radioactive deuterium and radioactive but fairly benign tritium. In the event that the magnets somehow fail, the reaction will stop, with just a bit of erosion on the sides of the reactor.
It was successful in that it fused deuterium and tritium. Of course, the break even point doesn't matter. To be economical, the reactor realistically has to hit ignition, which only the ITER could hope to do.
[i]One of Newton's laws is that Force = Mass * Acceleration. Rearrange this a bit and you get acceleration = force / mass. Decrease the weight/mass of the bullet and it will travel/accelerate faster. Hence, a lighter bullet could actually be good. [/i]
Bullet mass doesn't impact velocity that much. As somebody said previously, it more has to do with barrel length. A heavier bullet exits the barrel at an almost as high speed, but takes more energy from the gases.
They already have caffeinated energy drinks in the form of Sparks (absolutely disgusting). A problem with caffeiene and alcohol is that both are duiretics. That will make for a much worse hangover.
The television, airplane, the transistor, the CPU, AC power, and numerous other inventions and scientific achievements all belong to the US. Furthermore, the US is still the world leader physics, space exploration, and computer technology. I'd say that at this point in time, America still eclipses the rest of the world in science in technology, even if it doesn't in pure academics.
Good MBA programs are fairly difficult, and involve a lot of analytical skills, especially in the field of finance (which is quite similar to economics). Someone with an MBA and a Master's in CS could go onto become a quantitative analyst, where salaries can go well in excess of a half a million.
"They're good at the 'D' word, demographics," said Bruce Campbell, a star of B movies who also wrote, directed and starred in the "Screaming Brain" film, to be shown in September. "I think they're micromarketing," he said, "which in this fragmented world makes sense. They're saying, 'Who's at home on Saturday night?' "
Is there a chance that what you call "the expanding universe" is not the universe itself but a bunch of galaxies that happen to be closer to each other, and the universe is in fact much larger but we just can't see it?
Due to cosmic expansion of space by the Hubble Constant (which exceeds the speed of light over ultra-large distances) the vast majority of the universe is not visible. That's where the term "visible universe" comes from. But it certainly is not infinite.
ZPE is what they think is forcing the galaxies apart.
No, it isn't. Zero point energy is inherently useless as a power source. It is an equal and isotropic pressure across all space. It would be just the same as trying to use ambient temperature as an energy source. Just can't happen by thermodynamics.
Except that research shows that the human gene pool has a rather significant bottleneck, wherein we all descend from a small set of individuals not to far in the past. There is so little genetic variation in humans that if some of us have Neanderthal genes, then all of us do.
No, the genetic bottleneck occured far before homo sapiens escaped Africa and made contact with Neanderthals in Europe and the Middle East. H. Sapiens only reached Europe around 45,000 years ago. The genetic bottleneck occured 150,000 years ago or so in sub-Saharan Africa when humanity almost went extinct.
Thus, Asians and especially sub-Saharan Africans would show no Neanderthal genes, while caucasians would, if there was interbreeding.
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I'd like to point out that it is actually completely legal to prescribe drugs for "off label" uses. It is just very illegal to promote it.
Endoubitably, the cromulence of LCDs has continued to increase as well.
this is the problem. i dont know how many of you ahve worked with CS doctorates, but they are some of the most obtuse people i know, and dont generally have any idea what it is the average person wants or needs. (which, imho is what drives this industry)
For most ground level practical work, you're probably correct. But the people that make real waves are the super-smart PhD computer scientists and mathematicians. Think of Google, Alan Turing, Xerox Parc, etc.
Blasting something up with lasers is less expensive than using mechanical coupling. Though I agree, putting solar panels on the cars to power them is sort of silly. I'd run parallel rails up the beanstalk and let the cars tap the electricity.
There's something else you've overlooked: A car coming DOWN can use regenerative braking and feed power INTO the rails. If we're going to be mining for metals in space, we might wind up generating more electricity from the cars coming down than we'd spend in bringing cars UP. Net profit, even before selling the metals.
You can't use parellel rails. These cars would require thousands of amps, which is too much to carry in a poorly conducting carbon fiber ribbon which weighs one kilogram per kilometer. You'd need a big thick copper cable, which is unfeasable for obvious reasons. Thus, the energy must be beamed up by laser.
To low earth orbit, yes. But remember that the cable is stationary above the Earth, so one orbit is exactly 24 hours (it's more like 90 minutes in LEO). Thus, to move fast enough to actually be in orbit, rather than just falling back down to Earth, the elevator must go all the way to geosynchronous orbit, which is more like 24,000 miles out.
Ignition isn't Q=1. Breakeven is Q=1. To be economical, a D-T reactor's going to have to hit Q ~= 20; that is, 20 times as much energy coming out as you're putting in.
Ignition is what you get when the reaction sustains itself with no input energy at all; Q = infinity, basically.
That's basically what I was getting at.
although complex, if there IS a net gain, couldn't that be used to keep the reaction going, even without ignition?
That's pretty much the definition of ignition. It turns out you need a lot of net energy to keep everything at the proper temperature. So Q=1 is not nearly sufficient.
Magnetic containment. This isn't like fission reactions. There isn't a "pile." Just a couple of grams of non-radioactive deuterium and radioactive but fairly benign tritium. In the event that the magnets somehow fail, the reaction will stop, with just a bit of erosion on the sides of the reactor.
It was successful in that it fused deuterium and tritium. Of course, the break even point doesn't matter. To be economical, the reactor realistically has to hit ignition, which only the ITER could hope to do.
I'm not quite understanding "Must not loose!" Would it be bad for the USA to throw something?
[i]One of Newton's laws is that Force = Mass * Acceleration. Rearrange this a bit and you get acceleration = force / mass. Decrease the weight/mass of the bullet and it will travel/accelerate faster. Hence, a lighter bullet could actually be good. [/i]
Bullet mass doesn't impact velocity that much. As somebody said previously, it more has to do with barrel length. A heavier bullet exits the barrel at an almost as high speed, but takes more energy from the gases.
They already have caffeinated energy drinks in the form of Sparks (absolutely disgusting). A problem with caffeiene and alcohol is that both are duiretics. That will make for a much worse hangover.
Fortunately you would only need shielding on one side of the reactor. The waste heat problem does suck, however.
The television, airplane, the transistor, the CPU, AC power, and numerous other inventions and scientific achievements all belong to the US. Furthermore, the US is still the world leader physics, space exploration, and computer technology. I'd say that at this point in time, America still eclipses the rest of the world in science in technology, even if it doesn't in pure academics.
biologist, economist, statistician, or MBA
Good MBA programs are fairly difficult, and involve a lot of analytical skills, especially in the field of finance (which is quite similar to economics). Someone with an MBA and a Master's in CS could go onto become a quantitative analyst, where salaries can go well in excess of a half a million.
Just trail a thin wire through.
There isn't much in space. Even space junk isn't usually a huge concern.
"They're good at the 'D' word, demographics," said Bruce Campbell, a star of B movies who also wrote, directed and starred in the "Screaming Brain" film, to be shown in September. "I think they're micromarketing," he said, "which in this fragmented world makes sense. They're saying, 'Who's at home on Saturday night?' "
I love Bruce Campbell.
Some people have a different sense of humor than you.
Is there a chance that what you call "the expanding universe" is not the universe itself but a bunch of galaxies that happen to be closer to each other, and the universe is in fact much larger but we just can't see it?
Due to cosmic expansion of space by the Hubble Constant (which exceeds the speed of light over ultra-large distances) the vast majority of the universe is not visible. That's where the term "visible universe" comes from. But it certainly is not infinite.
ZPE is what they think is forcing the galaxies apart.
No, it isn't. Zero point energy is inherently useless as a power source. It is an equal and isotropic pressure across all space. It would be just the same as trying to use ambient temperature as an energy source. Just can't happen by thermodynamics.
Except that research shows that the human gene pool has a rather significant bottleneck, wherein we all descend from a small set of individuals not to far in the past. There is so little genetic variation in humans that if some of us have Neanderthal genes, then all of us do.
No, the genetic bottleneck occured far before homo sapiens escaped Africa and made contact with Neanderthals in Europe and the Middle East. H. Sapiens only reached Europe around 45,000 years ago. The genetic bottleneck occured 150,000 years ago or so in sub-Saharan Africa when humanity almost went extinct.
Thus, Asians and especially sub-Saharan Africans would show no Neanderthal genes, while caucasians would, if there was interbreeding.
It didn't exceed the escape velocity of the solar system, Einstein.
Scientists have pretty much discarded the interbreeding theory, as there isn't any detected neanderthal DNA intermixed with caucasian DNA.
Repeat after me 10 times:
Public debt is not like private debt...
The Great Depression was largely caused by overzealous stock speculation. America hardly had any debt at that time.