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This poster is entirely correct, except for one part.

imagine flying over Japan and watching North Korea

In truth, very detailed studies have found that the laser weapon the ABL uses, though flying in the stratosphere (above most weather) would be ineffective even though the thin clouds that sometimes form at that elevation. Even on a clear day, the range of the laser is quite limited, necessitating that the airplane fly within surface-to-air (SAM) missile range of North Korea to even hope of hitting any missiles. Iran was the other test case for this system, unfortunately Iran is much larger than North Korea, and the plane would have to be flying over Iran itself to be within range of interior missile sites.

This project is pretty much a handout to the defense industry and vestige of the beam weapon dreams held over from the Star Wars heydey under Reagan.

I happen to have written a semester essay (PDF) precisely on this topic. I wrote the essay for an excillent course that deals with nuclear weapons, ballistic missiles, missile defense, and arms control. The course website contains a host of up-to-date information and links, and is the longest running course of it's kind.

For a much broader and in depth view of boost phase missile defense, please see this APS study on the subject. I reccommend the brief, but informative executive summary. (PDF)

You can get the American Physical Society's report on boost phase missile defense here - its in lots of pdfs.

There is a lot of cool stuff in here. Airborne lasers are covered on pages 293 - 342.

Here are their conclusions from the executive summary

"Our main conclusions are the following:

1.Boost-phase defense against intercontinental ballistic missiles (ICBMs) hinges on the burn time of the attacking missile and the speed of the defending interceptor rocket. Defense of the entire United States against liquid-propellant ICBMs, such as those deployed early by the Soviet Union and the People's Republic of China (China), launched from countries such as the Democratic People's Republic of Korea (North Korea) and Iran, may be technically feasible using terrestrial (land-, sea-, or air-based) interceptors. However, the interceptor rockets would have to be substantially faster (and therefore necessarily larger) than those usually proposed in order to reach the ICBMs in time from international waters or neighboring countries willing to host the interceptors. The system would also require the capability to cope with at least the simplest of countermeasures.

2.Boost-phase defense of the entire United States against solid-propellant ICBMs, which have shorter burn times than liquid-propellant ICBMs, is unlikely to be practical when all factors are considered, no matter where or how interceptors are based. Even with optimistic assumptions, a terrestrial-based system would require very large interceptors with extremely high speeds and accelerations to defeat a solid-propellant ICBM launched from even a small country such as North Korea. Even such high-performance interceptors could not defend against solid-propellant ICBMs launched from Iran, because they could not be based close enough to disable the missiles before they deployed their munitions.

3. If interceptor rockets were based in space, their coverage would not be constrained by geography, but they would confront the same time constraints and engagement uncertainties as terrestrial-based interceptors. Consequently, their kill vehicles (the final homing stage of the interceptors) would have to be similar in size to those of terrestrial-based interceptors. With the technology we judge could become available within the next 15 years, defending against a single ICBM would require a thousand or more interceptors for a system having the lowest possible mass and providing realistic decision time. Deploying such a system would require at least a five- to tenfold increase over current U.S. space-launch rates.

4. The Airborne Laser now under development could have some capability against liquid-propellant missiles, but it would be ineffective against solid-propellant ICBMs, which are more heat-resistant.

5.The existing U.S. Navy Aegis system, using an interceptor rocket similar to the Standard Missile 2, should be capable of defending against short- or medium-range missiles launched from ships, barges, or other platforms off U.S. coasts. However, interceptor rockets would have to be positioned within a few tens of kilometers of the launch location of the attacking missile.

6.A key problem inherent in boost-phase defense is munitions shortfall: although a successful intercept would prevent munitions from reaching their target, it could cause live nuclear, chemical, or biological munitions to fall on populated areas short of the target, in the United States or other countries. Timing intercepts accurately enough to avoid this problem would be difficult."

And 8550% more volume in 11-dimensional space!

I never understood how quantum cryptography is not vulnerable to normal man in the middle attacks.

It is vulnerable, or at least present protocols are. True, once the secure channel is set up, a MITM can be detected, but the problem lies with the initial key exchange. It is impossible to be sure that the transmitted quantum key belongs to the person it claims to come from.

There have been proposals to circumvent this problem (e.g. using a trusted center), but the problem always remains the same. If the channel between Alice and Bob cannot be trusted, the channel between Alice or Bob and the center may be insecure as well.

Guess why the last meeting (march) of the American Physical Society (APS) was held in Montreal...

Also, guess why the APS have in their website a section related to visa information.

Guess why the last meeting (march) of the American Physical Society (APS) was held in Montreal...

Also, guess why the APS have in their website a section related to visa information.

At least all those other technical areas have had even less money invested in them than space launch - so there's good reason to hope all the needed breakthroughs can be made soon - with some R&D money.

"This is no more going to lead to a new superweapon [in and of itself] than any other increase in efficiency in power generation: we already have nuclear fusion bombs."

Uhhh.. NOT.

Apparently you haven't been paying attention. Most of the research in progress at the national labs deals not with larger-yield weapons, but with smaller-scale weapons. From Park's What's New column of November 28 of last year,

The $400B Defense Authorization bill was signed by the President on Monday. Among other things, it lifted a decades-old ban on research into low-yield nuclear weapons and authorized $15M for continued research on a nuclear bunker-buster. The deal was that only 6.1 (basic) and 6.2 (applied) research could be funded. Advanced development (6.3), which includes testing, is ruled out, but that's clearly where we're headed.

Where does NIF come into this? It gives direct experimental measurements of materials under extreme conditions. That data (equation of state, opacities, etc.) is what goes into computer simulations which bomb builders use.

The prospect of the US developing low-yield nuclear weapons, which could ultimately fall into the wrong hands, should scare the hell out of you.

Weinberg's opinion is no news. Bob Park already said it in his book Voodoo Science: The Road from Foolishness to Fraud and in his testimony before the Commitee on Sicence, Subcommitee on Space and Aeronautics (April 9th, 1997)

Up until recently, most physics journals would accept electronic submissions only in LaTeX-format. That has, thankfully, changed now. Even the venerable APS caved in a few years ago.

Foreign Missile Developmentsand the Ballistic Missile Threat Through 2015

APS Study Group on Boost-Phase Intercept Systems for National Missile Defense

We can never build a foolproof system. The technical hurdles involved are immense and expensive, while the countermeasures are relatively simple and inexpensive.

How much money will it take to convince you that you're safe?
Why don't we buy North Korea if we're willing to spend billions of dollars a year on safety? Im sure the people in North Korea wouldn't mind not starving.

How's develpment on the transporter coming?

Quantum teleportation is progressing slowly. Teleporting electrons using quantum entanglment has been done. Scaling it up to macroscopic sizes and massively superposed states is not trivial.

The paper's going to be in Physics Review E, not Physics Review Letters, which is where your link led. Check out the first two sentences of the article:

Physical Review E has announced the publication of an article by a team of researchers from Rensselaer Polytechnic Institute (RPI), Purdue University, Oak Ridge National Laboratory (ORNL), and the Russian Academy of Science (RAS) stating that they have replicated and extended previous experimental results that indicated the occurrence of nuclear fusion using a novel approach for plasma confinement.

This approach, called bubble fusion, and the new experimental results are being published in an extensively peer-reviewed article titled "Additional Evidence of Nuclear Emissions During Acoustic Cavitation," which is scheduled to be posted on Physical Review E's Web site and published in its journal this month.

I did a search at the Physics Review E site, but it's not there yet.

Nevertheless, like you, I feel that the arrival of a press release before the paper appears is something of a red flag - Especially in this particular subfield of physics.

When scientists are sure of their data, the first thing they do does not involve a press release. I'll be more convinced once I've seen it in a reputable journal

Here's a link that summarizes a lot of this research the last time this went around.

Until this is confirmed with careful studies that really measure this effect on humans, I think a betting person would bet that this will go away. The hype, unfortunately, won't as most people still believer power lines are harmfull to your health.

NASA was planning only Space Station compatible orbits as one of the safety mechanisms

Note, this suggestion isn't original; I think Bob Parks made it somewhere in What's New.

Tooting my own horn dept: as I said here, Bush's Mars plan is wildly underfunded, and that unless there's serious funding the Mars plan 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. Decomissioning Hubble is exhibit A for that argument.

In answer to the original question, "Is repairing the Hubble worth 5 astronaut's lives?" I'd just like to say that I'll go. I'll risk my life for science (and maybe the adventure of a lifetime in LEO).

If you want the actual paper, and have access to the journal, it's published on the online version of Physics Review Letters Phys. Rev. Lett. 92, 040403 (2004)

abstract here for those with access.

And diamond made of pure C-12 is about 3500 W/mK. link (full article requires subscription). Natural diamond has only about 1% of C-13 but these isotopic impurities result in phonon scattering which slows down the heat transfer. At 0.1% C-13 concentration it is already about 3000 W/mK and these diamonds can be made albeit they are quite expensive.

This is great. It's not to do computations. Really, silicon is good and fast enough for that right now (of course it would be real cool if possible, but that won't work). However, couple this effect with phototransistors which already are in the domain of high frequency (at least theoretical results suggest so - 10 GHz here) and you end of with the dream of board engineers - forget wiring chips with metal. Interconnect them with fiber! Certainly with germanium it's gonna bit a bit difficult, but it's worth it: all you need to wire to chips is power, end of distance limit between chips, and forget problems of spilling something on the board! Even with current germanium version it'll work perfect for connectors between boards.

"Earlier experiments on the storage of light stored only the 'signature' of the light pulses in a process somewhat similar to creating a hologram," said Bajcsy. "There were no signal photons present in the medium when the light was being stored. Our experiment, on the other hand, 'traps' actual signal photons inside the rubidium vapour in such a way that the overall signal pulse does not travel."

They are quite literally stopping the light.

Photons are quanta of energy; they are quite incapable of being split or combined. Consult your local library for books on quantam physics...

You'd go to the public library to learn about physics? No wonder your understanding is so botched and incomplete... I suppose you think what happened in this experiment is a figment of everyone's imagination? Quantum electrodynamics predicted that photons can split decades ago, and now they've done an experiment to prove it.

Press release after a recent APS conference

Extended summary of research (PDF) and

Research projects currently underway by the same U of Michigan group. Some cool stuff. Check it out. The microwave noise project is the first link. Nice PIC of the setup. Also a couple audio files showing the noise interference to a cordless phone before and after the modification.

Press release after a recent APS conference

Extended summary of research (PDF) and

Research projects currently underway by the same U of Michigan group. Some cool stuff. Check it out. The microwave noise project is the first link. Nice PIC of the setup. Also a couple audio files showing the noise interference to a cordless phone before and after the modification.

Robert Park is best known as the wit behind the APS What's New newsletter, a fantastic weekly mailing of science and policy-related blurbs. Park is also responsible for Voodoo Science, a book that debunks science myths and demonstrates how to identify science scams.

While Bob Park's name still appears in the credits, I think his involvement with the newsletter has lessed somewhat since his run-in with an oak tree a few years back. The witty remark per sentence ratio just hasn't been the same.

Robert Park is best known as the wit behind the APS What's New newsletter, a fantastic weekly mailing of science and policy-related blurbs. Park is also responsible for Voodoo Science, a book that debunks science myths and demonstrates how to identify science scams.

While Bob Park's name still appears in the credits, I think his involvement with the newsletter has lessed somewhat since his run-in with an oak tree a few years back. The witty remark per sentence ratio just hasn't been the same.

Robert Park is best known as the wit behind the APS What's New newsletter, a fantastic weekly mailing of science and policy-related blurbs. Park is also responsible for Voodoo Science, a book that debunks science myths and demonstrates how to identify science scams.

While Bob Park's name still appears in the credits, I think his involvement with the newsletter has lessed somewhat since his run-in with an oak tree a few years back. The witty remark per sentence ratio just hasn't been the same.

Robert Park's a University of Maryland Physics professor (emeritus? on leave?), Director of Public Information, Washington Office of the American Physical Society and writer of the American Physical Society's weekly What's New column, and is the author of "Voodoo Science: The Road From Foolishness to Fraud." You can download his CV here , and it will basically tell you he's a scientific somebody.

What they said was correct at one time. It is no longer correct.

It actually isn't all that hard to predict their motion. There's a new mathematical tool, the Parker-Sochacki solution to the Picard Iteration, that has made great strides in the ability to predict this.

What's even better, this solution method is incredibly easy, conceptually simple, ideal for initial value problems, yields exact functional solutions, involves simple algebra [yes, that's right: simple algebra solutions to almost any set of partial differential equations] and turns out doubling precision for every iteration.

Oh, yes: there is a version out for Maple, too.

The solution that it turns out is a MacLauren series [functionally equal to the Taylor Series] dependant on as many variables as you need. However, for this you'd have everything dependent on time.

Also, this method *has* been used to predict planetary, moon, and asteroid motion. It works.

[PS: That last link has code for you code monkeys]

What they said was correct at one time. It is no longer correct.

It actually isn't all that hard to predict their motion. There's a new mathematical tool, the Parker-Sochacki solution to the Picard Iteration, that has made great strides in the ability to predict this.

What's even better, this solution method is incredibly easy, conceptually simple, ideal for initial value problems, yields exact functional solutions, involves simple algebra [yes, that's right: simple algebra solutions to almost any set of partial differential equations] and turns out doubling precision for every iteration.

Oh, yes: there is a version out for Maple, too.

The solution that it turns out is a MacLauren series [functionally equal to the Taylor Series] dependant on as many variables as you need. However, for this you'd have everything dependent on time.

Also, this method *has* been used to predict planetary, moon, and asteroid motion. It works.

[PS: That last link has code for you code monkeys]

Cold fusion is impossible: it goes against the Second Law of Thermodynamics.

Every announcement of somebody getting cold fusion to work is only a fraud or a mistake.

There's a good book by Robert L. Park (Nobel Prize of Physics) dealing with cold fusion and other scientific frauds (such as perpetual movement engines): Voodoo Science

Robert Park also writes a column for the American Physical Society.

Cold fusion is impossible: it goes against the Second Law of Thermodynamics.

Every announcement of somebody getting cold fusion to work is only a fraud or a mistake.

There's a good book by Robert L. Park (Nobel Prize of Physics) dealing with cold fusion and other scientific frauds (such as perpetual movement engines): Voodoo Science

Robert Park also writes a column for the American Physical Society.

A cool picture of one of the earlier experiments can be found here.

I think that anyone who plays games can attest to the fact that AI has already come a long way. A few short years back (the last two titles in the Doom series come to mind), the AI couldn't do much more than shoot a gun aimlessly. Now, in Doom III, for example, I'm going to hazard a guess that the AI can be set way up into the unplayable levels.

This is but one small segment of AI. The research into AI that is already going on with a much smaller sum of money (into neural nets and such), if it continues at this rate, may well come up with an equivalent intelligence far greater than the cockroach that you mentioned. The field of quantum computing also promises to open up new doors for AI.

As for your subject line, not only are the technical hurdles unsurmountable (impossible to get there in a reasonable amount of time, impossible to extract the raw materials for living once there, impossible to sustain an ecosystem--as the failure of Biospere II shows--and impossible to get back) that it is not worth the trouble, but Mars can already be explored satisfactorily with robots such as the rover that fascinated the world back in 1997. I would think we would have learned our lesson from Columbia that human lives are too valuable to gamble with when it is not necessary. (You can use these search results on the American Physical Society's site to find out the case against manned missions to Mars.)

The PBMR reactors are supposed to be immune from meltdown, since the fuel pellets are embedded inside spheres that prevent a critical mass, but that does not mean that they are guaranteed safe reactors.

They use graphite as a coolant, and there may be significant risk of a graphite fire (chernobyl, anyone?). Also, unlike a fuel rod, where the waste products are the fuel, the PBMR system produces much more waste, since the coolant and spheres must be properly disposed of.

Here's a link that discusses much of this. (apologies for the PDF, I know it sucks ass, but that's the format this is in)

It addresses well how the notion of differentiation, where movement is divided into inifitesimally small space and time intervals of constant motion, was crucial to the development of modern physics and how it sometimes fails in multidimensional physics of elementary particles.

Yes, the American Physical Society accepts LaTeX files submitted electronically. It is pretty big news that they are now about to accept Microsoft Word format as well. (Note that they just began accepting Word format this June - although PRL (the rapid communication journal) has been accepting since all of July 2002!)

The learning curve to latex is steep but not really long. Whatever you are thinking about doing in LaTeX has probably already been done, so try to get a template if you can and just begin playing around with it - this is the best advice I can give you.

I used word until I began my thesis. Then I learned latex, beginning with a sample thesis file from my friend. (But most universities have sample files on file somewhere if you ask around.) At the end I handed it in to be checked and the graduate division found about 4 or 5 formatting problems. The nice lady who broke the news to me was quite used to pitched battles with M$ word users unwilling to go back and even try to get word to make their margins line up - even with the help of good old Clippy. I told her none of the things she talked about were difficult to fix, and I had the new copy back in a few hours. She almost had kittens.

I now use latex for quizzes because it takes me about the same time to write the entire quiz that it would for me to enter two equations into the M$ word equation editor - and this is something that latex is kind of bad at (since consistant formatting, which is one of latex's strengths, is unimportant). At the end of last semester I ran dvipdf on all the quizes and put them up on my homepage. No one complained about unreadable formuli. I have tried this with Word files and there was much wailing and gnashing of teeth.
__________________________________________ _______

For physics publications, see the following: REVTex4

So he screwed us in scientific research how?

He has increased the budget of the National Science Foundation for the next fiscal year by only 3.2%, compared to 10.4% this year. He thereby ignores a law, which he has himself signed into effect, to double the NSF budget within 5 years.

Various important fields of research have to live with increases below the inflation rate. A group of Nobel Laureates and industry leaders already see the leading role of the USA endangered.

BTW, I'm not a US citizen, so I follow the political activities in the USA only very loosely. I'm sure you know the various budget proposals in your own country better than I do, so you should have no difficulties in understanding what Bush does to your scientific research.

This was also stated some years ago by Robert L. Park in his book "Voodoo Science".

And this is the second time I recommend this book in Slashdot in two days. Hell, go and buy it!

Before talking about hydrogen vehicles, you should read Robert L. Park's "Voodoo Science". It explains clearly why all this hype about hydrogen is just crap.

Seems it has been accepted. Here is the abstract I found in the "Accepted Papers" section of PRL's site.

Seems it has been accepted. Here is the abstract I found in the "Accepted Papers" section of PRL's site.

Not much more information than in the article, but here's the abstract. This is pretty similar to Bragg scattering, which is a well known effect that uses sound waves to upshift the frequency of light. Current Bragg cells are very inefficient and are limited to small shifts in frequency. A high efficiency Bragg cell capable of shifting frequency by a large amount would be extremely interesting.

From Physical Review Letters.

Color of shock waves in photonic crystals
Evan J. Reed, Marin Soljacic, and John D. Joannopoulos

Unexpected and stunning new physical phenomena result when light interacts with a shock wave or shock-like dielectric modulation propagating through a photonic crystal. These new phenomena include the capture of light at the shock wave front and re-emission at a tunable pulse rate and carrier frequency across the bandgap, and bandwidth narrowing as opposed to the ubiquitous bandwidth broadening. To our knowledge, these effects do not occur in any other physical system and are all realizable under experimentally accessible conditions. Furthermore, their generality make them amenable to observation in a variety of time-dependent photonic crystal systems, which has significant technological implications.

For example, the famous protein crystals were no better than earth-grown ones, and the flu drug came from an Australian crystal, not a Space Lab 1 crystal.. Other than spiders in zero G, very little research has been done on the ISS (International Space Station), and none of it needed human minders.

For example, we could float about 10 more space telescopes for the cost of the ISS. And in fact, NASA repeatedly transferred money out of research to cover ISS cost overruns.

Don't get me wrong, the shuttles and the space station are great for inspiring school kids, but they really soak up $billions that could go to research.

As for shooting down Dinosaur Killers, what Bruce Willis movie have you been watching? An unmanned rocket that can send a robot to Mars can deliver a warhead to an incoming asteroid, and several ground based radars and space based telescopes can scan the skies much better than an astronaut looking out the ISS window!

For example, the famous protein crystals were no better than earth-grown ones, and the flu drug came from an Australian crystal, not a Space Lab 1 crystal.. Other than spiders in zero G, very little research has been done on the ISS (International Space Station), and none of it needed human minders.

For example, we could float about 10 more space telescopes for the cost of the ISS. And in fact, NASA repeatedly transferred money out of research to cover ISS cost overruns.

Don't get me wrong, the shuttles and the space station are great for inspiring school kids, but they really soak up $billions that could go to research.

As for shooting down Dinosaur Killers, what Bruce Willis movie have you been watching? An unmanned rocket that can send a robot to Mars can deliver a warhead to an incoming asteroid, and several ground based radars and space based telescopes can scan the skies much better than an astronaut looking out the ISS window!

For example, the famous protein crystals were no better than earth-grown ones, and the flu drug came from an Australian crystal, not a Space Lab 1 crystal.. Other than spiders in zero G, very little research has been done on the ISS (International Space Station), and none of it needed human minders.

For example, we could float about 10 more space telescopes for the cost of the ISS. And in fact, NASA repeatedly transferred money out of research to cover ISS cost overruns.

Don't get me wrong, the shuttles and the space station are great for inspiring school kids, but they really soak up $billions that could go to research.

As for shooting down Dinosaur Killers, what Bruce Willis movie have you been watching? An unmanned rocket that can send a robot to Mars can deliver a warhead to an incoming asteroid, and several ground based radars and space based telescopes can scan the skies much better than an astronaut looking out the ISS window!

For example, the famous protein crystals were no better than earth-grown ones, and the flu drug came from an Australian crystal, not a Space Lab 1 crystal.. Other than spiders in zero G, very little research has been done on the ISS (International Space Station), and none of it needed human minders.

For example, we could float about 10 more space telescopes for the cost of the ISS. And in fact, NASA repeatedly transferred money out of research to cover ISS cost overruns.

Don't get me wrong, the shuttles and the space station are great for inspiring school kids, but they really soak up $billions that could go to research.

As for shooting down Dinosaur Killers, what Bruce Willis movie have you been watching? An unmanned rocket that can send a robot to Mars can deliver a warhead to an incoming asteroid, and several ground based radars and space based telescopes can scan the skies much better than an astronaut looking out the ISS window!

Yes, Neutrinos have mass. This is old news dude.

When the neutrons get absorbed into the walls, they wreck so much havok on the material that the walls aren't really walls anymore; they're more like cottage cheese. That is a serious problem.

There was talk about creating some type of liquid wall that could absorb the neutrons and then be continuosly replaced, but I personally believe that this problem will ultimately be solved with transparent aluminium.

Boyd anticipates that the slow light device will find a role in the telecommunications industry. When two signals from fiber optic lines merge, the two signals may reach the merging router at the exact same moment and need to be separated slightly in time so they can be laid down one after another. Like two cars merging on a highway where one may need to slow down to let another car into the lane, a light-slowing device could help ease congestion on fiber optic lines and simplify the process of merging signals on busy networks.

However, there has been an interesting exchange (with comment and reply) in Physical Review Letters refuting such claims. (These are subscription journals but should be available in most academic and research institutions).

Finally, read the Seven Warning Signs of Bogus Science by Bob Park (even though rule 1 does not apply here).