Has anyone actually listened to it? Oh my! I never knew high density polyethelene shielding of high energy cosmic radiation could be so faaaabulous sssweeetiessss! Who knew Carson Kressley has such a keen interest in astrophysics...
How stupid can you get. This is a laser with a beam diameter of certainly less than a couple feet which probably can't fire for more than a minute or two. To suggest that it could even possibly be used as a WMD is laughable idiocy.
FYI this is NOT a liquid laser. The term "liquid laser" is barely ever used in laser research and when it is, its used to referr to DYE lasers which are absolutely not what is being discussed here. It could concievably be used to describe a chemical laser where the chemicals are liquid before being reacted to lase but this would be incorrect because lasers are typically classified based on the phase of the medium which undergoes lasing. In the case of the chemical laser the lasing medium is a plasma formed in a reaction chamber by the mixed, previously liquid, chemicals. It's a gas laser. From what I can tell here though, neither of these things is what is being proposed for the HELLADS system. It looks like what they're trying to do is match the index of refraction of a cooling liquid to the index of refraction of the slabs of lasing material in a SOLID STATE laser such as Nd:glass. Thereby allowing the efficient removal of heat from the laser material while it is firing and while also preserving the quality of the beam. I would be willing to bet they are looking at using ytterbium-doped strontium fluoroapatite (Yb:S-FAP) slabs immersed in a very dense transparent flowing liquid (perhaps even a molten salt like NaNO3) which is optically pumped by specifically tuned solid state diode lasers.
Has the simple fact that both of your lists are essentially true (to varying degrees), honestly escaped you? And that the world is perhaps a nastily complicated place where confounding dichotomies are often the state of things? (Hint: Ancient Greece had democracy and (proto)science but also had slavery) Or have you allowed yourself (as have some here in the US) to become so consumed by your own cynical and closeminded in your worldview that you are only capable of seeing truth in one of your lists? Hmm?
Oh please, irrational much? You could probably count the number of recorded fatal accidents in the history of MRI on one hand and how many people have had the procedure? Tens of millions, likely. The benefits of having an MRI so vastly outweigh the risks it is not even a tradeoff worth talking about at all.
Anywho, I think that MRI is easily one of the most strangely fantastic technologies of the last 50 years. Its like a bit of the 21st century accidentally fell into the last quarter of the 20th. Think about it. This is a device which you can slide a person into and 15-20 minutes later have high resolution (millimeter scale and now in 3D if necessary) images of any part of the inside of their body, making diagnoses of certain diseases which were impossible before, possible, and doing it without any harm (not even exposure to any ionizing radiation) to the patient at all. The patient feels, smells, tastes, and sees nothing whatsoever during the entire process. It is amazing. If ever there were a technology which met Arthur Clarke's maxim of 'any sufficiently advanced technology being indistinguishable from magic', then this is it!
Could be useful for extremely clean (class 1) cleanrooms where particle contamination is always an issue. With vinyl curtains, they are always open a little and have to be touched in order to move them aside to moving through. This contaminates them and they are not very easily cleaned. With a conventional door, even sliding ones, it has to be opened very wide, allowing lots of contamination to enter everytime someone uses it. This would be an elegant solution to both problems. I think it is a mistake however, to make each slat have its own detector. It should instead use a simple, single, (low power) scanning laser a foot or two before the door to quickly characterize the size and shape of the person about to pass through.
Yeah, exactly, there's nothing revolutionary or "disruptive" about it. Its crap. If he were really looking for a useful new design he'd be looking at something like this that automatically adjusts for maximum efficiency as external pressure changes.
The SrxAlxOx is not the important part though. It is what is DOPED into the strontium aluminate that is important. Note that is says Sr4AL14O25: Eu Dy. That means dysprosium and europium are doped into the matrix of strontium aluminate. THESE are the important dopants which are responsible for the extremely long phosphorescent glow times.
No actually, it isn't. If you dont HAVE to use it for hauling garbage you can use it for other far more important things. Like scientific experiments! The cost of a Progress resupply vehicle is less than 10% of a shuttle mission.
Well Mr.Knowitall why DON'T they? I'd like to know. As long as you separate out anything potentially very hazardous (radioactives, heavy metals) and you don't throw out massively huge chunks of metal likely to make it through a re-enrty then what's the big deal? MIR did it all the time using old Progress resupply containers. It'd certainly be cheaper than sending a shuttle mission every time.
Actually the current thinking is that we will probably not, in fact, be fucked. The Earth's field will flip but is not thought that it will disappear in the interim. It is currently thought (using geodynamo simulations on supercomputers and giant rotating spheres of hot liquid sodium in the laboratory) that the field weaken and become severely contorted but will not completely vanish. The recent article in SciAm "Probing the Geodynamo" explains things very nicely.
The attenuation losses from even very very good fibers is quite large though and this would absorb the light very quicly as well. Though, you mention the possible use of solitons and this IS very interesting. Unfortunately it is where my knowledge ends and I do not know the energy loss mechanisms of solitons. However, I very strongly suspect when considering a perfect "photonic storage" device we are violating some physical law, which one I cannot quite put my finger on though...........physicists?
In short. No. The trouble is in the absorption of photons by your reflective trap. See, even the most perfectly reflective surfaces we're capable of making (~99.999% reflective) are not good enough to do this. There is a technique for measuring the reflectivity of these (VERY) expensive mirrors called cavity ring-down where a laser pulse is injected into a cavity created with a highly reflective mirror and you watch how quickly that light pulse decays and this tells you very accurately the reflectivity of the thing. After only some tens of microseconds you are left with mere fractions of a percent of your original pulse. So in short, even with super reflective walls, your photon storage unit will still very efficiently convert those initial photons to heat in short order.
"Once China and India and Indonesia can get phone and power service to the medievil huts the majority of its population lives in, then I'd worry about the massive population difference."
And how far off do you really suppose this is? I give it around 20 years (barring some catastrophic collapse of the government there, where it doesn't dissolve and reform into democracy but instead anarchy and I don't see any good reason why this would happen). The cell phone, for instance, makes it insanely cheaper to give huge numbers of people phone service because all you gave to do is throw a tower up, no costly digging and wiring. What other inventions will they use to lift themselves from thier current "second world" status? It will be very interesting to see.
"The Hubble is a great scope, but we need to go farther. The hubble has flaws of up to 1300 nanometers. Where the magellan has up to 15 nanometer flaws."
Where'd THAT come from?! hubble was designed to have an abberation less than 1/20 waves at the helium neon laser line of 633 nm (30 nm). It ended up with an error of ~ 1/2 wave and anyway this is irrelevant because the error was corrected completely with costar.
Sigh... I've always said that cryogenic liquids were the way to go. You CAN'T tell me that a 20L dewar of liquid air piped directly onto the driver's lap would cost much more than a regular AC unit!:)
Slashdot Mirror
Has anyone actually listened to it? Oh my! I never knew high density polyethelene shielding of high energy cosmic radiation could be so faaaabulous sssweeetiessss! Who knew Carson Kressley has such a keen interest in astrophysics...
you are an imbecile
How stupid can you get. This is a laser with a beam diameter of certainly less than a couple feet which probably can't fire for more than a minute or two. To suggest that it could even possibly be used as a WMD is laughable idiocy.
FYI this is NOT a liquid laser. The term "liquid laser" is barely ever used in laser research and when it is, its used to referr to DYE lasers which are absolutely not what is being discussed here. It could concievably be used to describe a chemical laser where the chemicals are liquid before being reacted to lase but this would be incorrect because lasers are typically classified based on the phase of the medium which undergoes lasing. In the case of the chemical laser the lasing medium is a plasma formed in a reaction chamber by the mixed, previously liquid, chemicals. It's a gas laser. From what I can tell here though, neither of these things is what is being proposed for the HELLADS system. It looks like what they're trying to do is match the index of refraction of a cooling liquid to the index of refraction of the slabs of lasing material in a SOLID STATE laser such as Nd:glass. Thereby allowing the efficient removal of heat from the laser material while it is firing and while also preserving the quality of the beam. I would be willing to bet they are looking at using ytterbium-doped strontium fluoroapatite (Yb:S-FAP) slabs immersed in a very dense transparent flowing liquid (perhaps even a molten salt like NaNO3) which is optically pumped by specifically tuned solid state diode lasers.
Has the simple fact that both of your lists are essentially true (to varying degrees), honestly escaped you? And that the world is perhaps a nastily complicated place where confounding dichotomies are often the state of things? (Hint: Ancient Greece had democracy and (proto)science but also had slavery) Or have you allowed yourself (as have some here in the US) to become so consumed by your own cynical and closeminded in your worldview that you are only capable of seeing truth in one of your lists? Hmm?
Oh please, irrational much? You could probably count the number of recorded fatal accidents in the history of MRI on one hand and how many people have had the procedure? Tens of millions, likely. The benefits of having an MRI so vastly outweigh the risks it is not even a tradeoff worth talking about at all.
Anywho, I think that MRI is easily one of the most strangely fantastic technologies of the last 50 years. Its like a bit of the 21st century accidentally fell into the last quarter of the 20th. Think about it. This is a device which you can slide a person into and 15-20 minutes later have high resolution (millimeter scale and now in 3D if necessary) images of any part of the inside of their body, making diagnoses of certain diseases which were impossible before, possible, and doing it without any harm (not even exposure to any ionizing radiation) to the patient at all. The patient feels, smells, tastes, and sees nothing whatsoever during the entire process. It is amazing. If ever there were a technology which met Arthur Clarke's maxim of 'any sufficiently advanced technology being indistinguishable from magic', then this is it!
Could be useful for extremely clean (class 1) cleanrooms where particle contamination is always an issue. With vinyl curtains, they are always open a little and have to be touched in order to move them aside to moving through. This contaminates them and they are not very easily cleaned. With a conventional door, even sliding ones, it has to be opened very wide, allowing lots of contamination to enter everytime someone uses it. This would be an elegant solution to both problems. I think it is a mistake however, to make each slat have its own detector. It should instead use a simple, single, (low power) scanning laser a foot or two before the door to quickly characterize the size and shape of the person about to pass through.
Tip: refrain from rubbing unwashed pears on ballsack prior to consumption.
wtf!?
Really erroneus? What "time period" did you grow up in pray tell?
It says more about a school when it looks like thier entire site was made with geocities geobuilder and Front Page 97.
Lie.
Yeah, exactly, there's nothing revolutionary or "disruptive" about it. Its crap. If he were really looking for a useful new design he'd be looking at something like this that automatically adjusts for maximum efficiency as external pressure changes.
The SrxAlxOx is not the important part though. It is what is DOPED into the strontium aluminate that is important. Note that is says Sr4AL14O25: Eu Dy. That means dysprosium and europium are doped into the matrix of strontium aluminate. THESE are the important dopants which are responsible for the extremely long phosphorescent glow times.
Progress can haul back ~2 tons of trash. I'd say that's pretty economical.
No actually, it isn't. If you dont HAVE to use it for hauling garbage you can use it for other far more important things. Like scientific experiments! The cost of a Progress resupply vehicle is less than 10% of a shuttle mission.
Well Mr.Knowitall why DON'T they? I'd like to know. As long as you separate out anything potentially very hazardous (radioactives, heavy metals) and you don't throw out massively huge chunks of metal likely to make it through a re-enrty then what's the big deal? MIR did it all the time using old Progress resupply containers. It'd certainly be cheaper than sending a shuttle mission every time.
I bet there's no kind of atmosphere.
Actually the current thinking is that we will probably not, in fact, be fucked. The Earth's field will flip but is not thought that it will disappear in the interim. It is currently thought (using geodynamo simulations on supercomputers and giant rotating spheres of hot liquid sodium in the laboratory) that the field weaken and become severely contorted but will not completely vanish. The recent article in SciAm "Probing the Geodynamo" explains things very nicely.
The attenuation losses from even very very good fibers is quite large though and this would absorb the light very quicly as well. Though, you mention the possible use of solitons and this IS very interesting. Unfortunately it is where my knowledge ends and I do not know the energy loss mechanisms of solitons. However, I very strongly suspect when considering a perfect "photonic storage" device we are violating some physical law, which one I cannot quite put my finger on though. ..........physicists?
In short. No. The trouble is in the absorption of photons by your reflective trap. See, even the most perfectly reflective surfaces we're capable of making (~99.999% reflective) are not good enough to do this. There is a technique for measuring the reflectivity of these (VERY) expensive mirrors called cavity ring-down where a laser pulse is injected into a cavity created with a highly reflective mirror and you watch how quickly that light pulse decays and this tells you very accurately the reflectivity of the thing. After only some tens of microseconds you are left with mere fractions of a percent of your original pulse. So in short, even with super reflective walls, your photon storage unit will still very efficiently convert those initial photons to heat in short order.
"Once China and India and Indonesia can get phone and power service to the medievil huts the majority of its population lives in, then I'd worry about the massive population difference."
And how far off do you really suppose this is? I give it around 20 years (barring some catastrophic collapse of the government there, where it doesn't dissolve and reform into democracy but instead anarchy and I don't see any good reason why this would happen). The cell phone, for instance, makes it insanely cheaper to give huge numbers of people phone service because all you gave to do is throw a tower up, no costly digging and wiring. What other inventions will they use to lift themselves from thier current "second world" status? It will be very interesting to see.
Wow holy fucking shit you cracked it! Hundreds of physicists are left scratching thier heads but your stupendous intellect came through! 'tard.
"The Hubble is a great scope, but we need to go farther. The hubble has flaws of up to 1300 nanometers. Where the magellan has up to 15 nanometer flaws."
Where'd THAT come from?! hubble was designed to have an abberation less than 1/20 waves at the helium neon laser line of 633 nm (30 nm). It ended up with an error of ~ 1/2 wave and anyway this is irrelevant because the error was corrected completely with costar.
I know what cryocoolers are. It was a JOKE :)
Sigh... I've always said that cryogenic liquids were the way to go. You CAN'T tell me that a 20L dewar of liquid air piped directly onto the driver's lap would cost much more than a regular AC unit! :)