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send individual to tech schools; we have LOTS of people that don't comb hair or talk.

Any technology can be used for good or evil. A board with a nail through it can be the beginning of a house for the homeless, or an instrument to bloody someone to death.

I'm a huge fan of new technology and was wondering when someone would start to broach this area. I've read several pages of different universities that were playing with this including my favorite Caltech. This is great as it's a step away from just having the patient hardwired into a computer system.

Sean Mauch has a free online book covering several areas of applied mathematics. It's not complete, but I've found it useful. The page for the book is here.

Sean Mauch has a free online book covering several areas of applied mathematics. It's not complete, but I've found it useful. The page for the book is here.

When I used to work at the LIGO 40 meter prototype, the primary laser there put out 4 watts in its primary mode. That mode (frequency or color) was in the visible band, a brilliant green. If an object like a plastic pen crossed the beam, it would immediately start to smoke and melt. We did not experiment with fingers (or eyes!), but it was pretty target-independent.

If one were to have a matchbox-sized battery-powered device that emits four watts of continuous focusable light energy in the visible band, I would call that device a weapon. Or at least a component in one. Even the (yes, fictional) laser rifle desired by the Terminator was a pulsed 40W; ten of your 4W projectors would make a continuous 40W beam. The military name for that weapon would probably be the Force Projector.

The laser was really generating around 30 watts(!), but across a number of frequencies (colors). For the simple task of burning things (or lab workers) that small variation in frequencies wouldn't matter. Of course, this laser required 48000 watts (480 volts at 100 amps), so it wasn't exactly lossless, but it does give a sense that a 4W beam of light isn't exactly minor.

When I used to work at the LIGO 40 meter prototype, the primary laser there put out 4 watts in its primary mode. That mode (frequency or color) was in the visible band, a brilliant green. If an object like a plastic pen crossed the beam, it would immediately start to smoke and melt. We did not experiment with fingers (or eyes!), but it was pretty target-independent.

If one were to have a matchbox-sized battery-powered device that emits four watts of continuous focusable light energy in the visible band, I would call that device a weapon. Or at least a component in one. Even the (yes, fictional) laser rifle desired by the Terminator was a pulsed 40W; ten of your 4W projectors would make a continuous 40W beam. The military name for that weapon would probably be the Force Projector.

The laser was really generating around 30 watts(!), but across a number of frequencies (colors). For the simple task of burning things (or lab workers) that small variation in frequencies wouldn't matter. Of course, this laser required 48000 watts (480 volts at 100 amps), so it wasn't exactly lossless, but it does give a sense that a 4W beam of light isn't exactly minor.

Interestingly, this is also true in the laser printer realm. I got sick of paying ~$35 every two months or so for an ink cartridge, so I started looking for a decent personal laser printer. I settled on the Lexmark e210 because it's fast, cheap, and uses USB. Though I don't have to replace the toner often, it's still expensive (about $70 a pop!) and I didn't feel like shouldering the expense. That's when I discovered that the Samsung ML1210 takes the EXACT SAME toner except for a minor difference. The Lexmark toner has tamper-proof screws; the Samsung doesn't. So, you make your slight modification to the printer, you buy one Samsung toner cartridge, and then dump toner in whenever you need more.

Judging by some of Hajimiri's "selected works" (for example, "A 24 GHz CMOS Front End"), it appears that they're talking about the carrier frequency, not the data rate. Of course, higher carrier frequency generally implies more bandwidth, but this isn't a wireless 24 Gbps backbone.

or an air traffic controller, who didn't do their job correctly, people died. Which may have led to his death. Miscalculations in programming too can cause computer error which can lead to problems.

The comparison here is more of direct cause. IT people do not directly cause people to die but based on what they've designed, could cause accidents that may lead to deaths. It's easier to relate and understand a situation where a fireman fails to put out a fire in time which leads to loss of lives than it is to a programmer that writes code to round down instead of round up, thus causing a miscalculation in the software that eventually leads to a disaster that claims lives. Granted that at that point in time, the programmer does not realize their mistake because it's too far into the future and difficult to foresee and thus does not cause him stress directly. What about the supposedly computer glitch that failed to set off alarms that eventually led to the East Coast blackout? No deaths reported directly though.

Anyhoo, this could be a small example of The Butterfly Effect perhaps? (The theory not the movie).

In the manga, it shows a closeup of the vertical thrust vents on the bottom of the glider. There are no nozzles to rotate; a little hatch on the bottom swings open, and redirectors under the skin of the craft pump thrust out the new holes.

And as for whether it's a jet, I suspect it's either a pulsed-detonation engine or something a generation or three beyond that even. And the weight? well remember, this is a prototype. They didn't get the handles right, in shape or thickness, and there's a couple controls there that are missing on this guy's toy.

Would this be a good time to bring up Mechanized Propulsion?

Here's an introduction for idiots: hopefully it won't go over your head.

AGP was a hack onto PCI. PCI-Express will give us the symmetric bandwidth we need. Yeah!

I'm not sure what sort of image processing software NASA has. Astronomers are mostly using packages that are publically available, but not maintained by NASA. For the Magellan mission, Peter Ford at MIT made a great package called GIPS to reduce all the data. IPAC tends to make the image reduction pipelines for several missions as well as some ground based observatories, and they have some public domain software. The space telescope science institute has made their analysis software, built for hubble, publically available. They even contribute to open source numerical python libraries.

Caltech, SLAC, and LANL Set New Network Performance Marks

It would be difficult. I think you're talking about interferometry. This was originally developed for radio telescopes, and is harder to do at shorter wavelengths. The Submillimeter Array, working at the shorter submm wavelengths, has just opened on Mauna Kea, although some work has already been done with linking the James Clerk Maxwell Telescope and the Caltech Submillimeter Observatory. At optical wavelengths it gets harder still. An example is the Cambridge Optical Aperture Synthesis Telescope (COAST). There's also the proposed `Ohana project.

A major problem is that you have to preserve the phase information of the light when you combine the signals from the telescopes, so you can't just record images with a CCD (which only gets you the intensity) and then try to handle the rest of it in software.

Essentially this means that you'd have to combine light from the telescopes in real time and keep the path lengths between them accurate to a small fraction of the wavelength you're measuring. You can do this "off-line" at radio frequencies, for example with the Very Long Baseline Array (VLBA) but not at optical frequencies.

So, in summary, the Internet lets amateur observers collaborate in various ways. However, combining their optical telescopes to get the resolving power of a larger telescope (the size of the distributed collection of individual telescopes) through optical interferometry is not one of them.

Here are some links I dredged up last time this subject rolled through.

Wiki Textbooks
Light and Matter: Open physics textbooks.
An open math textbook
Project Gutenberg, for all the English majors out there.

There are also a lot of books out there which are freely downloadable, but not modifiable. Has anyone here used a free (in either sense) textbook as their primary learning tool in a college class? If so, what was your experience?

considering Bush's plan calls for a $1B increase in NASA funding over _5_ years, and plans for the first new moon landing is set for 2015.... it's obvious that Bush's plan is an investment into setting a new vision for NASA, not for implementing it. This is a big difference that I don't think many people fully appreciate.

This does raise some questions:

(1) What's the real mission gonna cost?

(2) How in the heck will we pay for it?
and most importantly:

(3) If we don't have really solid answers to (1) and (2), is a Mars study the best thing NASA can do with $5 billion?

I mean, think about it: That $5 billion would save the Hubble several times over, and fund more science missions like Mars Spirit Rover, Stardust GALEX, New Horizons, etc, etc. Doesn't it make more sense for the space scientists to decide how to spend the $5 billion than letting Washington politicians decide? The National Science Foundation, the National Institutes for Health, and DARPA all have a pretty good track record for peer-reviewed funding decisions; why not space science too?

Now think what you could build with that money in todays technology. I would suggest reusing some of the detectors designed for the next service mission. Use a modern light-weight mirror. No options for repear in space, just launch and forget. If it blows up, build another one. Mightbe be really modest in your goals, don't go for a design that is 10 times better than hubble, but try to equal it with a mirror of 1.5 - 2 meter. I don't know the exact number, but i believe SIRTF was built for something between 0.5 and 1B$. I would guess this could be done for less than 1B$ within 3 years to close the gap till NGST is built.

Really? Like 2 feet as in he's sitting in front of his PC? Oh, and it wasn't too long ago when laptops had 9-10" LCDs and people would read them all day long at 640x480 and 800x600.

I agree with the original poster: all the guy did was use a old Mac PC as a case for his PC. I have no clue why he even bothered with the Mac logo on his window, it's like putting a Camaro Z28 emblem on your Civic.

I'm not impressed and don't think this should have even been on /. There's far more impressive conversions you can do with a old Mac case IMHO.

Oops, I forgot to mention that there is a linux client & GUI available too.

Happy cracking.

That depends entirely on the Uni you're attending. I go to Caltech. Here, reports of cheating among undergrads are handled entirely by fellow undergrads. The profs, beyond detailing the evidence or making the accusation, have no direct role in the process. It's rather like a trial, and it works. Students do get terminated for cheating, and, well, so far I haven't heard of any lawyer monkeys being successful. It's surprising how well this system works, actually --- the cheating rate is something like 2%-4% at most, even though all our midterms, finals, and most of our quizzes are self-proctored take-home exams.

It's also not necessarily true that a Uni will lose business upon getting rid of a student. Heck, undergrads are almost viewed as a necessary evil at times here --- even for students paying full tuition and everything else, Tech spends more on us than we do on it.

You are right on. Where I went to college our homeworks were collaborative and our tests were take home and usually open book. We had a student body of 800 though. If I went from there to any large college and took a test, I would probably have felt like there was a given level of distrust because of tests being held in lecture halls and monitored by the professors or teaching assistants. However most people would argue that this is necesarry. I think the McGill students submitting their papers to the plagiarism website is really an identical albeit new practice.

Replacement - The replacement for the HST is due to go up in 2012, so there's a relatively small window with no orbital telescope (at least, if all goes well)

Exactly. As an astronomer let me assure you that all of these are absolutely worthless, and all scientific progress will cease once this horribly-redesigned-to-justify-a-manned-shuttle, wasn't-even-built-right-by-political-contractees turkey that's reached the end of its operative lifetime.

Actually, it is a shame in a purely emotional way. Just like when MIR was deorbited. But it's still the right call.

And I don't mean to demean the astronauts who at risk to their own lives got that POS in something like working order, and finally gave everyone some pretty pictures.

News Flash: most of our space science comes from unmanned machines such as the Space Telescope, the Mars Spirit Rover, the Stardust comet explorer, and others. Did I mention the Mars Global Explorer, the Wilkinson Microwave Anisotropy Probe satellite, GALEX, the Cassini mission to Saturn, Genesis solar wind sampler, the New Horizons Pluto-Kuiper Belt mission (planned for 2006), etc, etc. Voyagers 1 and 2 have been operating since 1977 (are they older than you?) and are approaching the heliopause. Now that's what I call space exploration. The truth is, in space, robots rule!

Folks, I'm sorry to inform you; but unless there's serious funding, this is at best a publicity stunt, and at worst a president micro-managing NASA in a way that will get rid of the few remaining actual science programs.

Actually the decaying orbit releases its energy as gravitational waves. They stretch and compress dimensions of space by tiny amounts. I would guess that grav. waves would have to be generated very close to us to cause problems. I know for sure that double neutron star systems that have a tight enough orbit to coalesce (and emit big grav. waves) are exceedingly rare, though.

Check out LIGO to find out more about gravity waves and our attempts to detect them. Also Just posted on science page is a double pulsar story that discusses gravitational waves.

As an aside, with a system this unique, and not to sound too much like a loon, but perhaps we should look for an ET presence. Not as the creators, but there maybe unique physical process than can be exploited in such a system, and doing so may give off a detectable technological signature.

I would be very suprised if they could actually "prove" the existance of such waves. Gravity is such a weak force compared to the other three (strong, weak, and electromagnetic) that pulsars light-years upon light-years away would be washed out by the gravitational effects of, well, the rest of the universe! There's been conjecture about this for years, and entire theories to try and resolve this problem of no detection (several string theories have been developed around this problem) We've even built miles long observation "tools" (like this one in Livingston, LA). However, if we can solve the background noise radiation, and the pulsars are close enough to earth, and have a large enough gravity, they just might do it! Einstein's theory of general relativity states that two orbiting stars (two orbiting anythings, but stars have a lot of mass and therefore gravity, so it would be pronounced) will 'shed' some of their momentum through gravity waves. The detection of these waves could revolutionize physics! It would allow us to determine the existance of the graviton, and if we ever did that, the world as we know it would change. Because once we pin it down, we can start converting energy to it, and probably start research on a feasible "anti-graviton" of sorts. Warp Drives, here we come! (well, not likely, but a guy can hope)

The Internet Archive serves the hidden purpose of preserving the AI source-code DNA of artificial Minds.
Each AI Mind leaves a source code trace of itself as it evolves and proliferates across the 'Net and the parsecs of nearby meatspace.
Robot Minds will be able to look up their ancestors in the Internet archive, just as we humans do. However, when the Joint Stewardship of Earth by man and cyborg has arrived in the form of the Technological Singularity, robots will be able to resurrect their AI Mind ancestors and bring them back to alife from the Internet Archive.

Information on the Caltech research can be found here.

One line of speculation that has actually given me a little extra paranoia over the last few years, is the Bastard Aliens From Hell :) I first ran across this in an old Analog, the idea being that a competitive species might think it quite rational to, ahh, remove any potential competition before they develop sufficient technology to become a threat. In the story, this was done with relativistic speed kinetic energy weapons - notoriously difficult to defend against because the speed would significantly cut down on the warning time.

So, a young species like our own that has just recently begun emitting detectable amounts of electromagnetic radiation is greeted by a Microsoft-like neigbor with some near light speed "cease and desist" planet busters. We've been emitting since roughly the 1940's - so if one of these is within 30 light years (and expanding, of course), the weapons should be arriving any day now...

Another good one is that there are significant technological dangers along the usual species development path that might cause civilizational level extermination in a large percentage of the cases. Our tech has just started to be powerful enough to do this - global thermonuclear or biological war, nanotech accidents (read up on "grey goo" for some bonus worry), self replicating weapons...

Or, maybe there's something like Vernor Vinge's "singularity" that generally happens to species not much more advanced than we are currently...

It's a shame Hubble is our only orbiting telescope.

There's more to the electromagnetic spectrum than visible light you know. The Hubble Space Telescope is only one of NASA's four orbiting "Grand Observatories". Here are links to info about the other telescopes.

• Chandra X-Ray Observatory
• Compton Gamma Ray Observatory
• Spitzer Space Telescope

My two favorites are the high-level representation form available in ANDF (over a decade old), and the typed functional approach of modern meta-complier frameworks like the Mohave system at Caltech.

In any case, I do also hope that Sun and related parties get experts on this precise topic involved so that the huge amount of research available in the field will not go to waste.

P.S.
I will TRULY be amazed/stupified if this gets modded insightful.

Researchers at Caltech and other institutions have been looking at this for about three years. See "Sparse Matrix Solvers on the GPU: Conjugate Gradients and Multigrid" by Bolz, Farmer, Grinspun and Schroder (SIGGRAPH 2003), for example. The paper, illustrations, and movies are available from Dr. Grinspun's homepage. The primary problems with the approach at the time this work was done was the limited bandwidth of texture-related operations in OpenGL based upon improper assumptions in pipeline optimization.

Yeah. There was a previous image, but it was a calibration image taken before the telescope had cooled down to its final operating temperature, and /. jabbered about it. To get good quality data they have to subtract a dark-field image (basically a shot taken with the lens cap on) from the image of the subject (and do other stuff), but when the telescope was warm it would have imaged its own heat. Makes for noisy data, which is why they imaged really infrared-bright stars. As we already know stars emit infrared, the scientific value of the image was to make scientists salivate over the prospect of better images in the future.

Yep, you've just described the singularity.

No offense to the Anonomous Coward but... (gotta love that line...)

I'm more interested in the telescope/project than the astronomer.

http://www.astro.caltech.edu/observatories/tmt/

Hmmmm.... Thorazine....

The ROPOD.

I am not an astronomer, but I am a physisist and I have been at recent talks given by cosmologists who are ecstatic about the recent developments, namely the concordance model. It gets the name 'concordance' precisely because it brings all of the previously seemingly paradoxical observations into 'concordance' in one single unified model.

Now it doesn't actually explain much (it is a model, not a theory), for example it says that almost all of the energy in the universe is in the form of 'dark' matter or 'dark' energy, and it gives rather precise figures for exactly how much dark matter and energy there is, doesn't say what dark matter actually is. Nor does it say anything about inflation theories (except that space is flat, and inflation is a plausible reason for this).

A link for large-scale structure is here. As for why galaxies collide, well, they attract each other gravitationally! If they are too close together, they collide. Where is the deep mystery? The link has more info on galaxy formation too.

Here are Terrestrial Planet Finder links at:

• NASA JPL (Flash animation)
• Caltech
• Space.com

How much does your nation give in foreign aid and assistance?

Perhaps you are referring to the ROPOD. I imagine aligning the lasers to project precise graphics would be somewhat more difficult than placing LEDs on a bar.

Caltech Streaming Theater

A paper of hers from 2001 presents information on the Mount Pinatubo eruption. An abstract of the paper discussed in the ABC story is also available.

A paper of hers from 2001 presents information on the Mount Pinatubo eruption. An abstract of the paper discussed in the ABC story is also available.

A paper of hers from 2001 presents information on the Mount Pinatubo eruption. An abstract of the paper discussed in the ABC story is also available.

No, the most successful class of Asynchronous circuits is wire length invariant. It's called QDI (Quasi-Delay Insensitive). The challenge is asynchronous logic is implementing efficient logic that obeys the hankshaking between concurrent processing elements.

Most of the popular press articles on async are bogus. If you really care, you should read some technical papers

It's your responsibility to *disprove* it with numbers: that's science. Meanwhile, your quibbles are easily dispelled:

Flares are BIG (I used the approximation "ginormous"). Even if the efficiency of the flare capture is .000000001% (probably lots more 0s than that), the payoff is bigger than all the chemical energy in the Earth's crust. Even 1990s microwave laser transducer tech is >90% efficient in e- -> uw -> e-, so once we've grabbed a tiny chunk at the scales we can process, we can hold on to it. Who says the power arrives in one pulse? The battery could be many sub-batteries, each accepting its maximum pulse, and pooled for discharge. Or maybe it's just a magnetic bubble in acute-ecliptic orbit, containing asteroidal nickel-iron, or several of them. The metal is lasered to plasma by the incoming pulses, which is condensed later to power lasers for discharge. The total storage of the battery is likely the bottleneck, so lots of the R&D would focus on that - great spinoff tech once the flare has passed, and we ride its wave until the next one.

With planning, civilization would become dependent on the *battery*, not the flares. Each flare is unpredicted, but the probability of a flare in a decade is predictable enough. And the energy to build, launch and maintain a dozen or so "Brilliant Pebble" satellites is already being expended now, for Star Wars tech more opposed to human development than supporting it. We can redirect that effort, investing it in a payoff that could overwhelm our scarcity-oriented security concerns with plenty. We don't worry that radioactive decay is unpredictable when we harness nuclear fission reactions in power plants, or that it's really energy-expensive to refine the fuel, because whenever the particles are inevitably emitted, the payoff is so huge. Solar wind power would use the mind-bendingly huge solar fusion power products in a flare to win the biggest lottery in history.

While we wait for a flare, the satellites would beam back the much smaller take from the ambient solar radiation, which itself would dwarf our terrestrial energy production. That's certainly worthwhile in itself for the power obtainable in a satellite's lifespan, with over 50KW/m^2 of light in at Mercury's orbit, not counting the kinetic power in the solar wind particles. The satellites pay big dividends immediately they are deployed, and the real payday comes when a flare ends their lifecycle in a blaze of glory. Once future generations deplete the battery, redeploy and catch another.

The perfect is the enemy of the merely good. We can hold out for "maximum efficiency", and miss everything, or do what we can with what we've got to get there, and actually get there.

"Just get away from the shady turf
And baby go catch some rays on the sunny surf
And when you catch a wave you'll be sittin on top of the world"

It is a picture from the Heath group at Caltech, and the wires are made in a so-called SNAP process. Read about it in the Science article (PDF)

From the description of the system it seems that they use superposition of polarization of photons. Any measurements across the path of the photons would destroy the superposition. Therefore, any amplifier that transforms optic data into electric data and back into optical would destroy the quantum state. However, purely optical polarization maintaining amplifiers exist and they might preserve the superposition.

Quantum state can also be transmitted via Quantum Teleportation but this is much more sophisticated.