Not neutrinos, muons. Neutrinos can barrel through a lightyear thick piece of lead without noticing, they only interact with normal matter via the weak force and are far too difficult to image with. Muons (leptons, -kinda like heavy electrons) which are continuously created in the upper atmosphere by cosmic ray collisions with the gasses there produce copious amounts of muons which rain down from abovde all the time. the muon has a short half life (2 microseconds) but are travelling so fast (high kinetic energy) that they experience time dilation (thx. Einstein!) and actually can penetrate thousands of feet into the ground before decaying/being absorbed. Because they have an electric charge (-1) they feel the electromagnetic force and are thus trivially easy to detect. So you can put an array of detectors below say, a pyramid, and simply look for areas where you see more muons on the array, that's where a void must be (less attenuation) and you go search there. I think this was done in the 60's by physicist Luis Alvarez. Here, for instance is an image of the shadow of the moon. Big deal you say? Well that image was taken "in muons" from 700 meters underground in the Soudan mine of Minnesota.
Wow so I guess from the "oh noes teh neutrons" drivel you're spouting here that you've never actually even read the wiki articles on fusion which all seem to address the issues of viability and neutronicity in extreme depth? Yeah, thought not.
"It is not clear from another plot where inertial confinement projects stand, except to say that they are still quite far from the ignition region."
Not exactly. In fact thermonuclear ignition will occur in the laboratory in ~3-4 years in an inertial confinement device. That's why they call it the National Ignition Facility. all scaled implosions and 3d simulations are pointing to fusion burn and HIGH GAIN from the NIF once its complete in a few years.
blue semiconductor lasers are EVEN MORE inefficient than blue LEDs. And I don't think (>microwatt level) UV semiconductor laser diodes that operate above cryogenic temperatures even exist yet.
"But probably the most significant future application for Shuji Nakamura's invention comes in the form of sterilizing drinking water, since the the water purification process can be made cheaper and more efficient with the use of ultraviolet LEDs. This can improve the lives and health of tens of millions people in developing countries."
This is absurd. No one with even the slightest clue about such things would ever make such a statement. Nakamura's blue and UV GaN/InGaN/AlInGaN leds and laser diodes are great but they will not be used for this purpose. The all emit in the near UV (350 nm or greater) this sucks for killing microorganisims. You want to cause a kink in a bacteria's dna by dimerizing adjacent thymine molecules, thus inhibiting replication. The germicidal efficacy curve which describes this phenomenon peaks at 260nm way below any LED with any kind of reasonable efficiency. A tenuous mercury plasma in a quartz bulb however, will blast out something like over 80% of its light right at this wavelength! There is no way you are going to beat the hugely efficient and dirt cheap germicidal uv lamps already on the market any time soon.
Can someone tell me why the above idiotic pablum is rated at a 4? Saying that CFCs "separate from air like oil and water" because they differ in molecular weight is so unbelieveably incorrect as to be lughable. and blaming the current "energy pinch" on the abandonment of CFCs in favor of HCFCs? hilarious. the above post is little more than contrarian cospiracy weaving cluelessness. hint: posts SOUNDING informative are NOT always such!
Why does anyone even use thier products at all anymore? Three little letters: A V G. after removing symantec's bloatcrap and installing AVG free its practically equivalent to gaining ~.5 GHz.
It it worth noting that the progress made in fusion research has been HUGE throughout the past 3-4 decades and while the next step is more difficult than the last we aew still making steady progress. JT-60 HAS attained a confinement quality in the deuterium-deuterium shots it has taken which are VERY good, so good that if they were done with deuterium-tritium mix they would firmly place JT-60 in the breakeven parameter space very near the ignition regime (they have not "gone DT" due to pain in the ass handling issues with the radioactive tritium). There is also always hope for a shocking surprise breakthrough too (but don't hold your breath). For example, 10 or so years ago, it was though there was no way you could get around having to build immensely expensive multi-hundred beam multi-MEGAjoule laser systems in order to make inertial confinement fusion work. Then along comes a cute little trick called Chirped pulse amplification and suddenly you can start talking about petawatt lasers being used to reduce the overall cost of the machine by 10 fold (fast ignition fusion schemes! That's why science is so great, there is always hope something better is just around the corner waiting to be discovered.
I disagree with most of your premise but it was the last line that really got me:
"Spending 30 minutes looking at Myspace will give you an indication of the amount of energy the NEXT generation will be willing to put into connecting online."
I can't look at Myspace for more than 30 seconds without requiring the use of a cyanide capsule. To imagine a world where Myspace morons run things is enough to make one contemplate building an isolated shack in rural Montana!
No, I'm afraid it is in fact a plasma. If you raise the temperature of a material sufficiently, the electrons become unbound from thier nuclei. that's a plasma. if you raise the temperature even further, the nucleons themselves dissolve, quarks become unbound from thier gluons (so to speak). that's a plasma too. and its called a quark gluon plasma.
??? there is no law stating that thermodynamic equilibrium must be defined as only applying to a group of whole atoms. the quark gluon plasma created upon ion collision is, for a time and in the tiny few cubic angstroms in which it is contained, certainly in thermodynamic equilibrium.
I would counter that by pointing out that a gold-gold ion collision on RHIC involves at least ~1200 particles (3 quarks per nucleon and a mass of ~200 AMU(daltons) per ion). this is to say nothing of the millions of particles that are created at the collision point and then explode outward (the kinetic energy of the fast ions is converted to mass). To speak of the 2 TeraKelvin temperature of a quark-gluon plasma of a heavy ion collision makes just as much sense as to talk about the 3 GigaKelvin temp. of a small amount of iron plasma in the Z machine.
I guess I still don't really "get it". Am I to seriously believe that throughout the entire 50 year history of pinch devices that nobody, until today, in the year 2006, has ever tried using wires wth a Z lower than W? I mean, that is just impossible. There had to be someone, somewhere along the line that wanted to investigate whether lower Z wires would cut brem. radiation losses or SOMETHING like that, so why is this effect only being discovered now? High energy X-ray spectrometers aren't THAT new!
oooh but just think, if you had a subscription you could've seen it even before the rest of us! ha. ScuttleMonkey has along with that other new editor, managed to flush any last vestiges of science story reputability this place ever had down the toilet long, long ago. This has got to be like the 50th bogus pseudoscience artice from "opensourcenergy" alone he's posted. I would be shocked to learn that/. even has a dozen subscribers left at this point. Who in thier right mind would actually pay to be insulted like this?
hehe. seriously. this is just an absolute joke./. has begun to suck so unbelieveably hard lately that I fear it may soon start to emit hawking radiation.
hmm no, when I said "the BIG shutdown" I mean THEE big shutdown, the final shutdown, the shutdown after which there can be no further shutdowns, the closing of the tevatron. I thought this was happening sometime soon after LHC starts up.....
interesting. I guess by shutdown, I meant..... "the big shutdown"....:( which must be coming down the pike pretty soon I'd imagine. Oh also one more if you please! Can you enter the tunnel AT ALL when the main ring is "charged" and particles are stored in it or is the synchrotron radiation too much of an issue to let people in there? I'm guessing you can't go in. (perhaps its not the synchrotron radiation that's a problem though b/c the protons are so heavy and maybe its because of random residual gas collisions with the beam? (cuz you musn't be able to get TOTAL vacuum and the beam must be SO intense and powerful....))
Here's something I have always wondered about. Doesn't the detector device (ie., CDF) eventually become so radioactive from being that close to the collision point that you just end up seeing particles flying everywhere from both the collision decay and the detector itself? It must get so messy how do you tell the difference!!? Also, when is the tevatron being shut down?
well...some people do.:D You can easily make the live feed of CDF and D0 from fermilab's tevatron into a simple screensaver. In fact, I rather like mine.:) Sometimes they shut down the feed and just keep cycling the last few frames but that's ok.
Slashdot Mirror
Not neutrinos, muons. Neutrinos can barrel through a lightyear thick piece of lead without noticing, they only interact with normal matter via the weak force and are far too difficult to image with. Muons (leptons, -kinda like heavy electrons) which are continuously created in the upper atmosphere by cosmic ray collisions with the gasses there produce copious amounts of muons which rain down from abovde all the time. the muon has a short half life (2 microseconds) but are travelling so fast (high kinetic energy) that they experience time dilation (thx. Einstein!) and actually can penetrate thousands of feet into the ground before decaying/being absorbed. Because they have an electric charge (-1) they feel the electromagnetic force and are thus trivially easy to detect. So you can put an array of detectors below say, a pyramid, and simply look for areas where you see more muons on the array, that's where a void must be (less attenuation) and you go search there. I think this was done in the 60's by physicist Luis Alvarez. Here, for instance is an image of the shadow of the moon. Big deal you say? Well that image was taken "in muons" from 700 meters underground in the Soudan mine of Minnesota.
Wow so I guess from the "oh noes teh neutrons" drivel you're spouting here that you've never actually even read the wiki articles on fusion which all seem to address the issues of viability and neutronicity in extreme depth? Yeah, thought not.
"It is not clear from another plot where inertial confinement projects stand, except to say that they are still quite far from the ignition region."
Not exactly. In fact thermonuclear ignition will occur in the laboratory in ~3-4 years in an inertial confinement device. That's why they call it the National Ignition Facility. all scaled implosions and 3d simulations are pointing to fusion burn and HIGH GAIN from the NIF once its complete in a few years.
the blasting through mountains part has its benefits. highway road cuts are fantastic places to go fossil hunting.
blue semiconductor lasers are EVEN MORE inefficient than blue LEDs. And I don't think (>microwatt level) UV semiconductor laser diodes that operate above cryogenic temperatures even exist yet.
"But probably the most significant future application for Shuji Nakamura's invention comes in the form of sterilizing drinking water, since the the water purification process can be made cheaper and more efficient with the use of ultraviolet LEDs. This can improve the lives and health of tens of millions people in developing countries."
This is absurd. No one with even the slightest clue about such things would ever make such a statement. Nakamura's blue and UV GaN/InGaN/AlInGaN leds and laser diodes are great but they will not be used for this purpose. The all emit in the near UV (350 nm or greater) this sucks for killing microorganisims. You want to cause a kink in a bacteria's dna by dimerizing adjacent thymine molecules, thus inhibiting replication. The germicidal efficacy curve which describes this phenomenon peaks at 260nm way below any LED with any kind of reasonable efficiency. A tenuous mercury plasma in a quartz bulb however, will blast out something like over 80% of its light right at this wavelength! There is no way you are going to beat the hugely efficient and dirt cheap germicidal uv lamps already on the market any time soon.
Can someone tell me why the above idiotic pablum is rated at a 4? Saying that CFCs "separate from air like oil and water" because they differ in molecular weight is so unbelieveably incorrect as to be lughable. and blaming the current "energy pinch" on the abandonment of CFCs in favor of HCFCs? hilarious. the above post is little more than contrarian cospiracy weaving cluelessness. hint: posts SOUNDING informative are NOT always such!
Why does anyone even use thier products at all anymore? Three little letters: A V G. after removing symantec's bloatcrap and installing AVG free its practically equivalent to gaining ~.5 GHz.
alpha testing more like.
It it worth noting that the progress made in fusion research has been HUGE throughout the past 3-4 decades and while the next step is more difficult than the last we aew still making steady progress. JT-60 HAS attained a confinement quality in the deuterium-deuterium shots it has taken which are VERY good, so good that if they were done with deuterium-tritium mix they would firmly place JT-60 in the breakeven parameter space very near the ignition regime (they have not "gone DT" due to pain in the ass handling issues with the radioactive tritium). There is also always hope for a shocking surprise breakthrough too (but don't hold your breath). For example, 10 or so years ago, it was though there was no way you could get around having to build immensely expensive multi-hundred beam multi-MEGAjoule laser systems in order to make inertial confinement fusion work. Then along comes a cute little trick called Chirped pulse amplification and suddenly you can start talking about petawatt lasers being used to reduce the overall cost of the machine by 10 fold (fast ignition fusion schemes! That's why science is so great, there is always hope something better is just around the corner waiting to be discovered.
Sigh... where is the -1 clueless mod when you need it?
I disagree with most of your premise but it was the last line that really got me:
"Spending 30 minutes looking at Myspace will give you an indication of the amount of energy the NEXT generation will be willing to put into connecting online."
I can't look at Myspace for more than 30 seconds without requiring the use of a cyanide capsule. To imagine a world where Myspace morons run things is enough to make one contemplate building an isolated shack in rural Montana!
No, I'm afraid it is in fact a plasma. If you raise the temperature of a material sufficiently, the electrons become unbound from thier nuclei. that's a plasma. if you raise the temperature even further, the nucleons themselves dissolve, quarks become unbound from thier gluons (so to speak). that's a plasma too. and its called a quark gluon plasma.
??? there is no law stating that thermodynamic equilibrium must be defined as only applying to a group of whole atoms. the quark gluon plasma created upon ion collision is, for a time and in the tiny few cubic angstroms in which it is contained, certainly in thermodynamic equilibrium.
beat you! :0) :)
I would counter that by pointing out that a gold-gold ion collision on RHIC involves at least ~1200 particles (3 quarks per nucleon and a mass of ~200 AMU(daltons) per ion). this is to say nothing of the millions of particles that are created at the collision point and then explode outward (the kinetic energy of the fast ions is converted to mass). To speak of the 2 TeraKelvin temperature of a quark-gluon plasma of a heavy ion collision makes just as much sense as to talk about the 3 GigaKelvin temp. of a small amount of iron plasma in the Z machine.
I guess I still don't really "get it". Am I to seriously believe that throughout the entire 50 year history of pinch devices that nobody, until today, in the year 2006, has ever tried using wires wth a Z lower than W? I mean, that is just impossible. There had to be someone, somewhere along the line that wanted to investigate whether lower Z wires would cut brem. radiation losses or SOMETHING like that, so why is this effect only being discovered now? High energy X-ray spectrometers aren't THAT new!
please note: you are an idiot. that is all.
oooh but just think, if you had a subscription you could've seen it even before the rest of us! ha. ScuttleMonkey has along with that other new editor, managed to flush any last vestiges of science story reputability this place ever had down the toilet long, long ago. This has got to be like the 50th bogus pseudoscience artice from "opensourcenergy" alone he's posted. I would be shocked to learn that /. even has a dozen subscribers left at this point. Who in thier right mind would actually pay to be insulted like this?
hehe. seriously. this is just an absolute joke. /. has begun to suck so unbelieveably hard lately that I fear it may soon start to emit hawking radiation.
you're stupid. HAND
hmm no, when I said "the BIG shutdown" I mean THEE big shutdown, the final shutdown, the shutdown after which there can be no further shutdowns, the closing of the tevatron. I thought this was happening sometime soon after LHC starts up.....
interesting. I guess by shutdown, I meant..... "the big shutdown".... :( which must be coming down the pike pretty soon I'd imagine. Oh also one more if you please! Can you enter the tunnel AT ALL when the main ring is "charged" and particles are stored in it or is the synchrotron radiation too much of an issue to let people in there? I'm guessing you can't go in. (perhaps its not the synchrotron radiation that's a problem though b/c the protons are so heavy and maybe its because of random residual gas collisions with the beam? (cuz you musn't be able to get TOTAL vacuum and the beam must be SO intense and powerful....))
Here's something I have always wondered about. Doesn't the detector device (ie., CDF) eventually become so radioactive from being that close to the collision point that you just end up seeing particles flying everywhere from both the collision decay and the detector itself? It must get so messy how do you tell the difference!!? Also, when is the tevatron being shut down?
well...some people do. :D You can easily make the live feed of CDF and D0 from fermilab's tevatron into a simple screensaver. In fact, I rather like mine. :) Sometimes they shut down the feed and just keep cycling the last few frames but that's ok.