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According to the original source, the bolide was 10 feet across, not 80 feet.

I've seen estimates of the 1908 Tunguska bolide being somewhere around 150 feet across. That bolide's explosion destroyed some 2000 square miles. The difference in damage is a function of the bolide's radius cubed so a doubling of the radius octuples the bolide's kinetic energy, assuming similar materials and velocities. There's a lot of uncertainty in these kinds of calculations because nobody knows much about the bolides in question. All that was left of the Tunguska event was a lot of destroyed landscape and in the case of the April 23 event, some recorded booms and flashes.

Other stuff we'd mine from the Moon because for use in space because it's much easier to get things to space from the Moon than from Earth. There's plenty of aluminum and titanium, both of which we already use in space. And there are a lot of oxides.

Clementine data shows where there are iron deposits, of up to 20% iron oxide. That's a low-grade taconite, although the processing techniques used on Earth would probably have to be modified for lunar gravity. Northern Minnesota has been mining taconite for a while. I don't know how hard it will be to find all the ingredients for steel on the Moon.

New Lunar Prospector studies suggest that the Clementine data is correct in location, but might be overestimating the abundance. Well, if we want to mine we'll be doing more prospecting -- at least we have LP maps and Clementine maps.

Other stuff we'd mine from the Moon because for use in space because it's much easier to get things to space from the Moon than from Earth. There's plenty of aluminum and titanium, both of which we already use in space. And there are a lot of oxides.

Clementine data shows where there are iron deposits, of up to 20% iron oxide. That's a low-grade taconite, although the processing techniques used on Earth would probably have to be modified for lunar gravity. Northern Minnesota has been mining taconite for a while. I don't know how hard it will be to find all the ingredients for steel on the Moon.

New Lunar Prospector studies suggest that the Clementine data is correct in location, but might be overestimating the abundance. Well, if we want to mine we'll be doing more prospecting -- at least we have LP maps and Clementine maps.

I think the better way to go with robots is the Mark Tilden route--BEAM

BEAM could work for large robots as well as it does for the bug size. As someone already pointed out dinosaurs had walnut sized brains. At the present time AI is so far from being feasible that you would only dely the introduction of truly useful robots while waiting for AI to catch up.

The interesting thing about Tilden's robots is they do inexplicable things like "learn"--they "remember" how to avoid obsticals, etc. Their resemblance to bugs is incredible.

Remember: Dinosaurs disappeared--cockroaches and beetles didn't.

Found a good page on Ruthenium, for those curious about it's uses, who discovered it, etc. 8-)

http://pearl1.lanl.gov/periodic/elements/44.html

• wx200d - a client/server based data collection and retrieval platform for Weather Station hardware.
  This solution requires a weather station, preferably an Oregon Scientific WM-918 or one of its variants (Radio Shack, etc.) You can write your own clients or use the shipping text-based, web-based or X-based client.

• gwx - X-based wx200d client
  This provides the same interface that the weather station hardware presents and connects to the wx200d server. It is multiuser and can support multiple monitor stations.

• wmWeather - a WindowMaker METAR retrieval system.
  This will retrieve live information from the National Weather Service right to your WindowMaker desktop. It sits on your dockbar and can query the station ID for your local city. No hardware is required.

Hope this helps. Have a good weekend!

-Pat

The best informed comment is probably the article itself. Check out pp.76-78 and the conclusions section.

Gravity at short ranges is being tested now (on scales of, like, inches) as a test of some superstring theories.

If gravity does not have a 1/r^2 dependence, things get really messy, really fast. First of all if you have to introduce a new length scale into the universe (such as a length within or beyond which a different law applies) then you have basically introduced a new constant of nature.

Secondly, it means that GR is wrong in some fundamental ways, so you have to work very hard to recover the successful tests of GR while still scrapping the guts theory itself.

Finally, remember that we HAVE tests of gravity at the ranges we're talking about -- Pluto's orbit is pretty well-determined, and Neptune and Uranus are out there, and Earth and Mars turn out to put very strong constraints on this, too (see the article for details, p.77); galaxies attract each other about the way we expect; there are plenty of long-period binary stars with this sort of separation that have been studied; etc.

I'm not saying that there's no way that gravity itself could be the culprit in the anomolous position of the craft; I'm just saying that the nature of gravity is pretty tightly constained by observation, so throwing stuff off like "it's different at large distances" opens a whole can of worms that have to be shoved back into some new theory.

The interstellar medium (interstellar gas & dust) is much less dense than normal around our solar system due to the Scorpius-Centaurus Association superbubble and the Geminga supernova bubble. Perhaps we're seeing a slight increase in the ISM density -- of course these researchers should know all about this, so it's still a puzzle...

Check out the JPL final paper on this.

Possibles are :
(a) Heat Ejection (b) Gas Leak (c) Clock Drift (d) Anomalous objects (pretty dead, despite BBC giving prominence) (e) modifications to gravity (f) solar radiation pressure (g) systematics of observations (h) antenna radiation pressure

Let the armchair speculation begin. (But remember to read the paper to check your answers!) Have Fun!

Notice, however, that they specifically suspect that a supernova shock wave could have caused what they measured. I assume that their literature search revealed the 35 kyr-old Be-10 anomalies, which probably were caused by a supernova shockwave. Indeed, footnote 4 (page 17 of PostScript paper) of "Geological Isotope Anomalies as Signatures of Nearby Supernovae" refers to Raisbeck finding a rise in the C14/C12 ratio during the period of this stalagmite study.

Of particular interest is Chapter 6, where they say the following:
Our starting point was the enticing notion of being able to run a quantum computer `for free'. The quotation marks here were very necessary, however, for it is not at all clear what if anything comes for free. A CF protocol requires the computer to be present, and due time must allowed for the machine not to run.

They go on to explain why any attempt to use the times when the computer is "off" for other computation will ruin the original computation. The bottom line is that the story is fascinating and the model may be useful for analyzing various phenomena, but apparently this trick will not save any physical resources beyond "standard" quantum computation.

Of more pseudo-practical interest is the issue of interaction-free measurement (the "bomb testing problem" mentioned in the paper). For a nice introduction see The Tao of Interaction-Free Measurements.

Of particular interest is Chapter 6, where they say the following:
Our starting point was the enticing notion of being able to run a quantum computer `for free'. The quotation marks here were very necessary, however, for it is not at all clear what if anything comes for free. A CF protocol requires the computer to be present, and due time must allowed for the machine not to run.

They go on to explain why any attempt to use the times when the computer is "off" for other computation will ruin the original computation. The bottom line is that the story is fascinating and the model may be useful for analyzing various phenomena, but apparently this trick will not save any physical resources beyond "standard" quantum computation.

Of more pseudo-practical interest is the issue of interaction-free measurement (the "bomb testing problem" mentioned in the paper). For a nice introduction see The Tao of Interaction-Free Measurements.

Well, as is, one could theoretically argue that the law would prohibit the use of hardware the contains proprietary microcode (since it is a form of software). An enterprising IT manager might be able to get copies of the Linux BIOS installed as a replacement for the regular PC BIOSes. However, such changes would take a lot of time and effort, wouldn't provide a substanial benefit, and still wouldn't address the issue of other installed microcode.

The easiest solution, in my mind, would be to include an exception clause (as others have pointed out). This would be especially important for cases where an open-sourced alternative does not exist (for example, try finding open-sourced firmware replacements for most hospital equipment).

Nod, see xxx.lanl.gov.

Tell me how this isn't the best way to get peer reviews. I wonder why other fields don't follow the Physicists' lead and make themselves a preprint archive...

"Creating a Global Knowledge Network"
By P. Ginsparg
http://cnls.lanl.gov/aux/oneday?daypat=20010425

If the went a step further and arranged for the peer-review process to take place, kept a second database for reviewed documents and distributed print versions for university libraries. They could basically replace all the old paper journal within a few year. Good thing too. Ditch the B-arkers.

Interesting. I don't see any problem with this and I could say I agree. However, the new theories mentioned in the article are explicitly about real higher dimensions. They say gravity is much weaker than other fundamental forces because, in a small scale, gravitational flux is spread out in a higher number of dimensions. Here is the theory paper.

In a way you could also argue that the three dimensions we know are merely a way of organizing our ideas about the surrounding world. If we never directly observe the dimension in which the spacetime is curved, it cannot be said to be real, but nevertheless it is a useful concept. You probably know there are many similar 'devices' in physics such as the quantum mechanical wavefunction. In the end reality is only what we perceive and even the three spatial dimensions are thus not real, for we only see 2-D projections of things. Now I better stop before going on deeper and referring to the Matrix ;-)

--

can be found here, at xxx.lanl.gov, which means it is free, and quite fast to download. (No banner ads or other bs)

can be found here, at xxx.lanl.gov, which means it is free, and quite fast to download. (No banner ads or other bs)

The confinement scheme you are talking about (commonly referred to as an "electrostatic confinement" or a "Penning trap") is actually closer to hot fusion than cold fusion. The device works by making a spherical electrostatic potential that both confines ions and causes them to oscillate about the center of the device. If the electric field is sufficiently strong that the relative speeds of the ions is high, then collisions among the particles can, on occasion, lead to fusion reactions.

This link takes you to web pages describing (and showing nice color photos of) an ongoing Penning trap fusion experiment being conducted at the Los Alamos National Laboratory. The main drawback to devices of this type for power production is that one is limited in the number of ions that can be confined (the Brillouin limit) due to space-charge effects. Even without achieving breakeven, these devices are still very interesting, however, as enough fusion reactions take place in a small enough package to make the Penning trap devices attractive neutron sources: unlike radionucleides, you have both an on-off switch (making them easier and safer to handle and operate), and you can dial the flux of neutrons you want (making them more flexible).

The confinement scheme you are talking about (commonly referred to as an "electrostatic confinement" or a "Penning trap") is actually closer to hot fusion than cold fusion. The device works by making a spherical electrostatic potential that both confines ions and causes them to oscillate about the center of the device. If the electric field is sufficiently strong that the relative speeds of the ions is high, then collisions among the particles can, on occasion, lead to fusion reactions.

This link takes you to web pages describing (and showing nice color photos of) an ongoing Penning trap fusion experiment being conducted at the Los Alamos National Laboratory. The main drawback to devices of this type for power production is that one is limited in the number of ions that can be confined (the Brillouin limit) due to space-charge effects. Even without achieving breakeven, these devices are still very interesting, however, as enough fusion reactions take place in a small enough package to make the Penning trap devices attractive neutron sources: unlike radionucleides, you have both an on-off switch (making them easier and safer to handle and operate), and you can dial the flux of neutrons you want (making them more flexible).

Try xxx.lanl.gov

My lisp instructor recently gave a keynote speech at Los Alamos entitled When are we going to get it right. The speech does a great job covering many of the security issues regarding double click and just the overall state of security on the web. Its a good watch if you have the time. You can see the whole thing in realvideo from the link above.

-gerbik

Sure, Kevin. I'm a 42-year-old guy with a degree in engineering, but who happens to find all this breakneck-paced technological development fascinating; I guess it suits my temperament. In that my daughter is going into the field (genetic counseling, which apparently combines the disciplines of genetic and ethics; she wants to help people make decisions in light of the advances available to them via genetics / proteomics et al). I find it incredibly fascinating (I think I mentioned that) because the ramifications of all this knowledge - what being able to do with it means to us as a culture and a society - are far-reaching. You yourself are going into the field of medical science and there are profound ethical questions you will wrestle with. I determined early on that I needed harder science, but found that my dilemmas were no less difficult. The arena of global thermonuclear warfare can be tricky as well.

It is good that you agree that public discourse on the subject is not only valid, but vital. I grew up believing in the ideal of the pure scientist, one for whom questions of ethics didn't really exist because his motives were purely driven by his inquisitive nature. In this day and age, unfortunately, that isn't the case. One can never be sure of an individual's trustworthiness; in fact it is the danger in this technology being delivered into the wrong hands that is often a big argument for continuing research wherever it might lead, so that we might be able to combat the "Dr. Evils' of the future world when they discover the technology independently*. This was also the argument in the 1950's for continuing research on atomic weapons. I don't have to tell you where that led: Plutonium Injections, the 'Green Run', and all sorts of environmental clean-up issues that persist today.

I don't know how to stop the incredible hubris of people, now that pure scientists don't exist so much anymore, or if they do, are overshadowed by greedy and evil men, or utter fools. But I can set them all up for one massive 'told ya so'!

What I meant about those questions should not need to be raised: hypothetically, sure, but perhaps not in real life. My kids have a cousin who was born to two Moms... so far, so good. Oh! That made me think of a fleeting thought I had about an hour ago. Such births to me (sorry if I offend) are not about loving a child, they are about people having a child for themselves. I actually do consider such acts selfish ones. Creation of a child out of Love comes only from God. There goes the Luddite side of me again. I sincerely do not get all excited about the possiblities of cloning. Genetics, sure, but not cloning. I am not a religious man, but I like to think I know God a little, and I am pretty sure that the job of creating life is still best left to Him. We are bound to cock it up!

BTW, you will almost Never see me comment on Linux issues or servers, although I read the posts. Programming in perl will have to be done in a future life. heh, maybe my clone will pick up on it...

One more personal note: you should not post as an AC, you have too much to offer this forum, and unless astute moderators pick up on your posts and elevate them, we might never get to see them.

*- and the fact that, as it turns out, cloning is not much more difficult than IV fertilization makes it especially dangerous. Very few people today can build a back-yard H-bomb.

Umm....maybe. After this "direct detection" was announced, another group, with BETTER detection capability, failed to find the claimed signal.

The original group then admitted that the supposedly directly detected planet was not so bright

Why all the controversy?

the signal was 20000 times fainter than the noise

Repeat:

the signal was 20000 times fainter than the noise

More than you ever wanted to know about this star

----
cliamer: IAAPA

Umm....maybe. After this "direct detection" was announced, another group, with BETTER detection capability, failed to find the claimed signal.

The original group then admitted that the supposedly directly detected planet was not so bright

Why all the controversy?

the signal was 20000 times fainter than the noise

Repeat:

the signal was 20000 times fainter than the noise

More than you ever wanted to know about this star

----
cliamer: IAAPA

Sorry, I'm new at this. The inventor has disavowed the press release. Look down the middle of this page. This is the original press release.

The inventor has disavowed the press release. Look down the middle of this page. This is the original press release.

This wouldn't be suitable for most computing applications, where designing software for a generalized processor would be easier and more effective most of the time.

But for dedicated and experimental electronics, it'd be golden. Just think how much this would accelerate prototyping and design for BEAM robots, since you don't have to mess around with soldering bunches of components!

According to this article from the LANL e-prints server, MgB2 appears to be a phonon mediated BCS superconductor. Of course, since the initial discovery was only a few weeks ago, it is hard to say.

These BEAM robots - among them the featured one - are in most cases nonprogrammable, hardwired machines like photovores. While small, simple robots have a certain fascination, quite a number of them are extremely "dumb" (because hardwired). It can be quite a lot of fun to work with these, though.

In contrast, there's lots of activity over at LinuxBIOS.

since a lot of projects like linuxBIOS and real time linux are starting to mature. Why use "somewhat free" when you can have "all free."

Anybody know where to buy a small (set-top sized) case for a Micro-ATX motherboard? I don't need any space for drives, because it won't have any.

Research is, in fact, one of the most open sourced processes going on.

Researchers get their status and thus their grant money from the number of publications and the number of times their publications are quoted by other publications, so it is in their best interest to make publications as easily obtainable as possible

For example, check out the arXiv preprint archive, which contains a large proportion of all publications in physics (at least for my field, soft condensed matter physics), in postscript and LaTeX source (!).

Of course, commercial journal publisher (like Elsevier) use this to obtain full copyright on articles, and publishing them in journals which cost 10s of thousands of dollars for a subscription. A good university or institute can't do without them, because they have a natural monopoly on what's published.


Sander

...LinuxBIOS or some other embedded Linux kernel.
Tetris on drugs, NES music, and GNOME vs. KDE Bingo.

LinuxBIOS LinuxBIOS Home also posted last June on Slashdot here at LinuxBIOS Project will give you the ability to have any startup logo you wish, allow for faster reboots, better system configuration and also get rid of all the obsolete BIOS support for things like DOS.

DocBook is your friend

DocBook is a lot to digest at one time, but it is well worth the effort. Personally I prefer DocBook XML and use Norm Walsh's XSLT stylesheets to transform the XML to anything I want... HTML, PDF, whatever.

Here are some resources for your reading pleasure.

• OASIS DocBook Site
• Norm Walsh's DocBook Site
• Get Going With DocBook - Mark Galassi
• SGML for Windows NT
• DocBook tools

DocBook is Open Source, freely available on all platforms of interest, can be used for simple documents to complex books, separates presentation from content, and is extensible. What more could you want from a document format?

I hadn't heard of DocBook, so I went fishing on docbook.org for some basic info.

The state of the documentation for this product is fairly lacking. (Hey, it's a DOCUMENT application!) There's no "getting started with DocBook" stuff. There's no official tutorial.

The closest thing to a tutorial I found is this page: DocBook intro. I'll excerpt the front page.

• DocBook intro

• Here is my tutorial on DocBook. I never completed it, but it is still useful, since others don't focus on a complete beginner tutorial.

  Last modified: Mon Jul 27 11:19:57 1998

Frankly, this sums up my issue with many Open Source projects: making a technically superior tool is not enough to generate wide user acceptance. There has to be an easy migration path from what the user's already got.

DocBook needs at least ONE of the following to get people going:

RTF/DOC/FrameMaker/TeX to DocBook converters, supporting at least a good 75% of basic features,

A usable migration tutorial that assumes the user already makes RTF/DOC/FrameMaker/TeX documents,

A usable editor that shows the results, even if it has to be two-paned to show both source and results.

I'm not flaming Open Source in general, but this is not the first time I have heard of a tool that would fit my needs exactly, except they put very large barriers to entry in my path.

Here's a link to the scientific paper

We do have people working on it. Instead of Intel doing it though, we have some Linux hackers taking a stab at it. Check it out - Linux Bios project.

http://xxx.lanl.gov/pdf/quant-ph/9910032 is a link posted by user freeinformation. This is a redirect to a 19 page PDF file by Dr. Bandyopadhyay.

Is looks to me like this guy Supriyo Bandyopadhyay really is doing some good work.

Is not simple though. I couldn't see the average graphics designer learning to code in it. Thanks to macros and variables Tex is more than a markup like its also a Turing complete programming language, though is almost never used that way. The print quality is wonderful. Its such a downgrade to be writing stuff in even the todays best word processors, you never match the quality of the automatically constructed fonts that Metafont provides. Need a gothic Aleph in 600dpi, it will be constructed on the fly. Finally Donald Knuth did literally write the book on computer science. Yes I love Latex more than a german fetishist ever could. IBM alphaworks did a believe construct a brower for LaTex some three years ago. It was called something like techworks. But it never caught on and I wouldn't expect it to now. Its doesn't have the bitmaps graphics porn appeal or crappy banner adverts, and just wouldn't be marketable on todays internet.

But just try writing the Einstein field equations in HTML. no, well here it is in Tex.

$$ G^{\mu\nu} - \Lambda g^{\mu\nu} = 8\pi T^{\mu\nu} $$

There is some work that is already in progress for integrating TeX (and LaTeX) with the Web. One procedure is to convert LaTeX to HTML - done by programs like latex2html . What the original post is asking for - is done by HyperTeX.

One reason that LaTeX would not be popular is the way it forces you to write well structured documents - something that can be done in HTML if you wish, but you won't be forced to do so. The more common objection to LaTeX - cryptic commands and no WYSIWYG editor - LyX provides a decent enough WYSIWYG editor.

So, some crazy wording going on here. Think Carbon 12 vs. Carbon 14, both have percentages in carbon based life forms that allow for Carbon 14 dating to be applied... now slide down a row in the periodic table, and we have Silicon. Both are have four valence electrons, but silicon is our favorite for making semiconductor devices. Now in order to make semiconductors, you need to have "pure" silicon in the first place, which you can then add dopants to to make it an n-type (negative charge carriers) or p-type (positive charge carriers) semiconductor. This electronics grade silicon is elementally pure, but as this article suggests, isotopically not... (some atoms weigh more, extra neutrons!!!)

Now isotopically pure silicon requires that you separate out all of the heavier silicon atoms in your batch, so you only have the "perfect" 14 protons, 14 neutrons and 14 electrons. As one could guess from some general knowledge of thermodynamics, and crystal lattice structure, an isotopically pure crystal would have a natural tendency to shake in a purer way (hence have temperature) without little heavier marbles, (the Si with more than 14 neutrons) becoming centers (defects) holding more heat ( 1/2(mass)(velocity^2) <- mass gets higher, more ability to hold higher than the average kinetic energy and mess up the nearest neighbor atoms and melt the little solder droplets or copper channels or whatever they're afraid of).

So to review.

• Isotropic: having the same properties in all directions throughout the crystal.
• Isotopic(ally pure): the same number of neutrons in each atom... which will then effect the directional isotropy of the bulk crystal.

Perhaps most interesting is the cost of this... Any way I can think of to split off the heavy atoms is not cheap, so hence the isotopically/isotropically pure silicon boules -> wafers get more expensive...

hopefully I haven't put in extra r's where they shouldn't be and confused people more... aaaargh... stupid words.

Fun isotropy fact: Tungsten is the most isotropic metal around, all of it's properties are the same in every direction!... w00t. (it is also highly resistive, but has a reeeeeally high melting point)

Looks like college is paying off... ... err...

at http://xxx.lanl.gov/pdf/cond-mat/0007048

The full article is available without subscription to PRL ... you can get it from the lanl archive here.