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While this does seem to be cheaper, and while I'm all for putting up solar power where it makes sense, when it makes sense, and all that, even with those improvements I wouldn't look to things to change all at once or anything. We're not going to be demolishing all the glass in our buildings to install this technology any time soon.

The best technology usually advocates itself.

Indeed, correct. Just to put a tangible front on that very valid theoretical answer, light, RF, etc. (the propagation of electromagnetic radiation) does not need a medium to wiggle around in. This is why it can traverse space so efficiently. Instead of a medium, the electic and magnetic fields wiggle each other.

Furthermore, EM emission of "stuff" is a bit weird. I assume you speak of a "photon" as stuff, however a photon can be simply thought of as a packet of energy. But a photon is simply a wave and vice versa. This is certainly an easily confused subject in which this link provides a bit of insight

So, I fail to understand the cause for your last statement.
I said There is no ``dark matter'' (i.e. exotic matter) and ``dark energy'' seems unlikely.
You seemed to object to my statement; you said "Actually... dark energy is one of the hottest fields in physics right now... I'd sure like to see the source for your statements.". Perhaps I was incorrect as viewing this as an objection to my comment; for the sake of argument, let us assume you were objecting. If you propose a new "mechanism" in physics (scalar field, whatever), you should have some reasonable explanation of how it works. Does "dark energy" arise from quantum mechanical effects? Is this a new "Higgs Field"? Right now "dark energy" is just a ad hoc theory for explaining observations, one form of which happens to bring back Einstein's cosmological constant. The history of physics includes many instances of ad hoc theories (e.g. steady state cosmology) which are proposed and later discarded. Based on this history, I would guess that the probability "dark energy" is correct (in the appropriate sense in physics) is less than one-half. (It is also my personal view that dark energy is not the correct explanation for current observations.)

There's lots of explanations of the original double slit experiment, like this and this (the second one is a java applet demonstration)

This experiment was originally performed with light and proved that it behaved like a wave. Essentially when two waves combine you can get constructive interference when they pile up on top of each other, or destructive interference when they cancel each other out. This can be observed as an alternating pattern of light and dark on a screen or photographic film.

Since 1905, however, we also know that light behaves like a particle. If we reduce the intensity of the light being shone at the slits to the point where only one photon is being emitted at a time, then you'd think that it would either go through one slit or the other. Since there's only one photon then there should be no interference effects. That's what I'd expect to happen anyway, but it turns out this isn't what happens - an interference pattern is still produced. This means that the photon must have passed through both slits, but it can't have passed through both slits because it's an indivisible photon and this is an example of quantum mechanics not making any sense. It doesn't make any sense to anybody, but somehow it's still a useful theory.

Later last century physicists performed the same experiment with 'real' particles like electrons, atoms, bucky-balls etc and got the same results. The particle went through both slits, but can't have gone through both slits because it's just a single particle..

This 'interference' in time experiment is very similar, but instead of an electron passing through different slits it is emitted from an atom at different times. This produce an interference pattern because, for example, the 'crest' of the later one will arrive at the detector at the same time as the 'trough' of the earlier one. But it can't have been emitted at both times because it's just a single electron ... you get the idea.

SIV seems harmless to chimps, but HIV seems harmless to people until they come down with AIDS. And if SIV never proceeds to an AIDS like condition in chimpanzees we do not know whether it was the chimps that adapted to the SIV, or the SIV that became less virulent to be able to spread better in chimps. I for one wouldn't bet on a not very virulent disease like HIV having any incentive to provide many more than 10 or at most 20 symptom free years in the name of spreading better, and I wouldn't expect the evolution from a moderately good spreader ( 10 years symptom free ) to a very good spreader ( 20 years symptom free ) to happen quickly.

If it was not the virus that evolved, but the chimps, then I would not neccessarily expect humans to have the genetic diversity to field an effective defense. Then again, a very small number of humans are natually immune to it ( search for "Naturally immune to HIV" in quotes using google to find it mentioned but not featured in various articles ).

One might assume HIV is anologous to Syphilus ( SIV evolved in chimps to become less virulent instead of chimps evolving to tolerate it ) but that would be baseless. There are people who have been multiple strains of HIV, and reinfection with syphilis after cure with antibiotics is possible.

Infection with one strain does not confer immunity to all strains ( or even the original strain ). This means that for all intents and purposes, each strain is a seperate disease not in competition with the other strains any more than say, HIV and Syphilis are in competition with each other or the common cold.

More virulent strains of Siphilis died out on their own because visible sores disgusted potential sex partners and probably caused pain for the infected genitals that made sex too painful to engage in. They did not die out because of competitive pressure from less virulent syphilis strains.

There are probably a panoply of Siphilis strains that are adapted to produce more or less infectious sores with strains that produce more sores winning out by better spreading where antibiotics are not available and sores don't cause the host to obtain an immediate antibiotic cure. Where antibiotics are available, almost invisible cases that spread less easily win out, living under the radar of their infected hosts for long periods of time.

Therefore the existance of a less virulent strain of HIV that doesn't cause AIDS, therefore doesn't neccessarily mean the extinction of the more virulent strains.

But the presence of the less virulent phage-infected HIV will make it's hosts immune to non-phage infected strains of HIV, since the presence of the phage will mean any newly aquired strains are immediately infected so phage infected strains WILL be in competition with phage free strains, and so will act as a vaccine that may wipe out HIV sans phage like smallpox.

What evolutionary pressures will the new HIV+phage strain face? Will a person infected with HIV+phage be able to transmit the disease as easily as a person infected with only HIV was able to? Will there be pressure to develop other forms of virulency to increase transmission rate? Maybe the phage, which now requires HIV to survive will lose it's ability to prevent AIDS.

The HIV+phage strain will not face some of the barriers to spreading that HIV alone faced. A person infected with 'harmless' HIV+phage would not be as careful about spreading it as they would be about spreading HIV. People won't be as careful about not getting 'harmless' HIV+phage as they were about not getting HIV alone.

If

It's not a tempory name. That's it's offical IUPAC name.

No and yes. According to the article:

A committee will vote at this weekend's General Assembly of the International Union of Pure and Applied Chemistry (IUPAC) in Ottawa, Canada. It is expected to approve the element's informal moniker, 'darmstadtium', and give it the chemical symbol Ds.

According to IUPAC's naming rules for elements 101 and up:

The systematic names and symbols for elements of atomic numbers greater than 103 are the only approved names and symbols for those elements until the approval of trivial names by IUPAC.

In other words, the systematic name is official until a trivial name is approved. This means that the systematic name, although official, is temporary. In the case of ununnilium, it may shortly be officially renamed to "darmstadtium", which would imply that the name "ununnilium" is temporary.

That season (1997/1998), the fires spread because the forests were unusually dry. This was partly because it was an El Niño year, which caused severe drought.

But human activity was probably a more important factor--in the mid '90s large drainage canals were cut in the peat forests (as part of the Mega Rice Project), which dried out large areas of peat; and large areas of the forest have been damaged by other activities, especially logging. So the fires spread along the banks of the drainage canals (see this article from the Guardian), along logging roads, and in general, areas where humans had damaged the forest--pristine areas were far less affected by the fire, even when they did burn. (See Satellite shows how logging makes forest more flammable, which is based on an article in the Nov 22 2001 issue of Nature.)

So, yeah, I'd blame humans for this fire--they started the fires, human use of the forest made the fires both larger and more damaging than they would have been otherwise. El Niño was a huge factor in the spread of the fires, but humans made it way worse.

While the carbon released by the fires is something to worry about, these fires also caused a big loss of biodiversity. Borneo is one of the few places where orangutans are found in the wild, along with other endangered primates. The fires are thought to have killed thousands of orangutans and destroyed much of their habitat. This wouldn't be such a huge problem--forest can grow back, after all--except that Borneo is being heavily deforested, because of (largely illegal) logging, conversion to farmland, and so on. At current rates of deforestation, some think that Borneo's forest might be essentially gone in two decades, driving orangutans, proboscis monkeys, and other species to extinction.

Incidently, since these fires were burning in peat, some of them never really stopped--the peat has just been smoldering for years. It's an El Niño year right now (much weaker than '97/98), and there are fires on Borneo again (or at least there were, as of August--it's hard to find current information, though you can look at the Global Fire Monitoring Center's webpage for southeast Asia). Another chance to take measurements of carbon emissions, I guess.

There are lots of information sourced from documents at this page.

Maybe the discover will revolutionize the way humans feed - should help French vine to be even more flavorful too? :)

The said it was "a pentamethylcyclopentadienyl cation" which tells you exactly what they made if you have the right secret decoder ring.

penta- means five -methyl- refers to a methane group; a methane group is a carbon with all it's free bonds capped with hydrogen.

pentamethyl- means it has five methyl- groups dangling off of it; they don't tell us where, but we'll shortly see why they didn't bother.

-cyclo- means the base structure is a ring. -penta- is five again -dienyl- means alternating single and double bonds like so ...--C==C--C==C--C==...

-cyclopentadienyl- means that it's a ring of five carbons with every other other bond double. But wait, you say, what does "every other mean" in a five element ring? Thus we get to...

-cation means it's got a positive charge, so the whole bonding picture may be off, with the double bonds playing resonance leap-frog around the ring.

As for what it's good for, that depends. It could be good for a thesis, or for tenure, or for funding, or...it all depends on where you are in the food chain.

-- MarkusQ

No, Copyright is not exclusive. Several people can share the copyright on one work and you can grant copyright to other people without invalidating your own copyright. So much about theory. In practice many publishers want you to grant (transfer) them exclusive copyright for unlimited future (so that you lose you right to copy your own work!). See e.g. the case of Eric Weisstein vs. CRC Press LLC, esp. point 5 in the Author Agreement. Some suggestions how to deal with publishers with respect to copyright can be obtained from the Mathematical Copyright page.

• VTKis a very good package for scientific visualization.
• Maxima is a Free computer algebra system, a bit like Mathematica. It can solve equations, do calculus, plot things, produce TeX output of what you've done, and lots more. Incredibly useful for long tedious bits of algebra.
• gnuplot is a versatile graphing package (2D and 3D, but maxima or VTK are IMO better for 3d stuff). As well as graphing, it can try to fit arbitrary functions to your experimental data.
• LaTeX -- it's very hard indeed to typeset equations better than LaTeX can.

A program in Equus was a constructive variety of "worm" program that sought out computing resources and adapted to changing environments.

See

T. Kindberg, A.V. Sahiner and Y. Paker (1987). Worm Programs, Distributed Operating Systems, Theory and Practice, Y. Paker, J-P. Banatre and M. Bozyigit, eds., NATO ASI Series F, vol. 28, 1987, pp. 335-379.

or

Equus: an Environment for Reconfigurable Distributed Computations, Tech. Report no. 591, Queen Mary & Westfield College Dept. of CS, 1992.

• Paul Verhelst, Computer Chess Programming. Includes many other links.
• T.A. Marsland, The Anatomy of Chess Programs. International Computer Chess Association.
• A.N. Walker, Notes for a course at the University of Nottingham.
• Fox, Williams, and Messina. Chapter from a book called Parallel Computing Works.

in 1993 the British Minister for Science challenged particle physicists to explain in one page or less what the Higgs Boson was and why they were so eager to find it.

http://hepwww.ph.qmw.ac.uk/epp/higgs.html

i think even if you spend 1 billion $ for a 100m aperture telescope on earth, that a e.g. 20m telescope in orbit will be better. Also i think that there's too much "competition" in the huge telescope market, we've got the GTC, the LBT, the SALT, the VISTA, the LAMOST, the DMT, the CELT, the XLT, the OWL, the LSST, the GSMT, the MAXAT, the ELT. Why? why not make only one bigger/better on earth, or even in space? the 2.4m HST proved the bettest scope is in space.
--
BeDevId 15453 - Download BeOS R5 Lite free!

'The Great Linux Debate'
Outside the show
Mailbox Internet

Abashed the Devil stood,
And felt how awful goodness is

'The Great Linux Debate'
Outside the show
Mailbox Internet

Abashed the Devil stood,
And felt how awful goodness is

'The Great Linux Debate'
Outside the show
Mailbox Internet

Abashed the Devil stood,
And felt how awful goodness is

Windows95 used to include the Sun PC-NFS client that might do what you're asking, but I'm not sure (as the last time I used Windows95 was several months ago and I don't have a test system to mess with).

If you're just trying to get Windows (NT) to log into an NIS domain, you can have a look at NISGINA. There's a neat article at LinuxWorld here. I poked around with this before I discovered Samba, but never really tested is. NISGINA's hopme page is here. NISGINA (and it's subsidiary utilities) come with source, too (which is nice).

Sun (I think..) also makes an NIS/NFS client for Win32 -- there's a technical run-through here. It's called the Solstice NFS Client for Windows and it probably doesn't come cheap.

Now, if anywone knows where I can get a cheap/free Macintosh NIS/NFS client... (and yes, I know about Netatalk, but I'd like to try anyways)

For several different explanations of Higgs, try http://hepwww.ph.qmw.ac.uk/epp/higgs.html . It's the results from a challenge to try to explain Higgs and its meaningfulness in one page.

The Higgs theory is an attempt to understand how particles have mass, by postulating the existence of a particle/field that interacts with particles, giving them mass.

I'm no physicist, so I would recommend taking a look at a few good, brief and easy-to-read essays, written by real physicists, on the Higgs theory here. I would especially recommend the essay Politics, Solid State and the Higgs, if only for its humourous content.

The Higgs theory is an attempt to understand how particles have mass, by postulating the existence of a particle/field that interacts with particles, giving them mass.

I'm no physicist, so I would recommend taking a look at a few good, brief and easy-to-read essays, written by real physicists, on the Higgs theory here. I would especially recommend the essay Politics, Solid State and the Higgs, if only for its humourous content.

Didn't happen, I believe :P

Still, I suppose scientists have to think about such matters. In this case, I'd say go for it! Mad science! Bwahaha!

Linux note: HEPpc: Linux Resources f or High Energy Physics