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Here's a link to some background on neutrinos, and particle physics in general (from the American Institute of Physics).

The basic idea is this: neutrinos seem to be fundamental particles. The more we understand about them (properties, interactions, etc) and the other elementary particles, the more we understand about how the universe works. This usually has "practical" applications in fields like astronomy and cosmology first. But don't worry, eventually there will be nice day-to-day applications (neutrino toasters, etc :-)

Heres a link to the actual artical in the Industrial physicist: http://www.aip.org/tip/INPHFA/vol-8/iss-2/p12.pdf

It seems as though its weather that would prevent us from using the earth as the primary solar center. Also it seems we are already exposed to microwaves as part of industrial radio, cell phones and other high frequency output devices.
The plan involves sending small manufacturing groups to the moon to both mine on the moon and use the supplies to build the solar bases. Kinda like MCV's(mobile construction units for all you non C&C players out there).

I on the otherhand think its just a secret plan created by doctor evil to put a "laser" on the moon.

There's an analysis called Skepticism Greets Claim of Bubble Fusion on Physics Today's web site.

Imagine fission at the turn of a switch!

Also, radioactive waste may not be a problem. Laser induced fission.

Essentially it means that radioactive waste can be recycled. Bombarding it with laser induced neutrons can force it to fizz until it is no longer radioactive, while hopefully still generating more energy than the laser costs to run. A second benefit is that nuclear plants no longer need to maintain critical mass. Turn on the laser, and watch the nuclear reaction go, turn off the laser, and see it stop!

Radioactive waste may not be a problem, actually. Laser induced fission.

Essentially it means that radioactive waste can be recycled. Bombarding it with laser induced neutrons can force it to fizz until it is no longer radioactive, while hopefully still generating more energy than the laser costs to run. A second benefit is that nuclear plants no longer need to maintain critical mass. Turn on the laser, and watch the nuclear reaction go, turn off the laser, and see it stop!

This article should be under "Science", not "Television". After all, wasn't Chuck Jones the discoverer of the cartoon laws of physics? ("Any body suspended in space will remain in space until made aware of its situation," etc.) These laws of nature are now common knowledge, probably even more so than laws from more stuffy, traditional branches of physics.

The main contoversy is over Heisenberg's interpretation of his role in the German WWII effort. In a book by a Swiss journalist (Brighter Than a Thousand Suns )Heisenberg claims that because of his refusal to work on the bomb the Nazis did not obtain it. The problem with his version is the fact that transcripts were taken secretly in the U.K. where many of the German nuclear physicists were held after being captured in Germany by the allieds (out of fear they could work for the Russians later!). From these transcripts it is concluded that the German effort concentrated on building a reactor to breed plutonium and use that as bomb fuel (hence the importance of heavy water, which is used to moderate reactors). It is very likely that the Germans overestimated the amount of fissible uranium needed for a chain reaction (critical mass) by a huge amount and therefore did not attempt to separate uranium isotopes.
The problem with Heisenberg was therefore perhaps not so much his role in WWII, but his dramatic reinvention of his role after the war. The Bohr papers again suggest that the failure of the German nuclear effort was due to Hitler being uninterested and their miscalculations rather than heroic resistance.
Things are of course very complicated and I am very impresessed by Bohr's handling of the whole affair.

Can be found here (in PDF form), for all those who like reading physicists physics.

This article discusses your question in the "Long before the Planck scale" section; the idea is that the size of the extra dimensions brings down the "effective" 4D Planck scale from the usual 10^19 GeV to about a TeV.

Apparently you something call a penning trap which does indeed use electromagnetic fields.

I find it particulary interesting what Carl Friedrich Freiherr von Weizsäcker exclaimated in this conversation:

I don't think we ought to make excuses now because we did not succeed, but we must admit that we did not want to succeed.

OK, there are many ways to interprete this, but it is a very interesting statement.

Actually, I asked Joseph Rotblat what he thought happened in Copenhagen that day. He didn't answer, really, he just pointed out the many different possibilities, but he did put some emphasis on the possibility that the group did block the development.

helps to explain how they're achieving this with a graphic representation. Still a little technical for me, but it kinda makes sense.

. . .take a look at some issues of Computing in Science & Engineering; they have a website, although much of the actual content isn't free. You'll find some successful OO applications there.

Since we don't have any idea how complex the simplest self-replicating molecule is, speculating on the odds of its forming is a bit pointless, don't you think?

However, if we're talking about something that actively seeks out food to convert to more of itself, either a larger ``it'' or more ``its,'' the smallest known (Mycoplasma genitalium) consists of 470 genes (another poster placed this at 400) with a 580,000 base-pair genome, of which about 300 are absolutely essential. Informed speculation has gone as low as 100 genes (which would imply around 130,000 base-pairs), going beyond this requires a hive- or colony-like structure and some means of collating enough genes to start a new group collective organism.

By contrast, each of your cells harbours DNA to the tune of around 3 billion bases. If a strand of this DNA were unwound, it would be several meters long. If your proteins also uncurled you'd look like the dust puppy from UserFriendy. At the other end of the scale, one of the smallest known (parasitic) organisms is the Q-beta virus, at 3 genes totalling about 4500 base-pairs. This is a long, long way from standalone.

This brings to mind the Tierra program (sorry, couldn't find a good link). It was a system that simulated evolution in a simple way.

It's been a while since we heard anything about Pioneer's anomalous acceleration. This sounds like the sort of thing that might be able to shed a little light.

Yeah yeah, it's all funny but it ticks me off that nobody is pointing out that The principle illustrated in Schroedingers "cat" thought experiment are NOT THE SAME as the Heisenberg Uncertainty Principle. In fact, it ticks me off that nobody knows what the Uncertainty Principle is really about and people constantly confuse it with the whole indeterminate quantum particle state and whether does in fact create quantum indeterminacy on the macro scale (if a tree falls in the forest...) issue. Heisenberg's Uncertainty Principle establishes a mathematically defined absolute uncertainty balanced between the momentum and position of a quantum scale particle. The corresponding thought experiment would be the gamma ray microscope.

That is the spookiness of quantum mechanics. See here for a summary of quantum teleportation using entangled particles.

The article seems to imply that you need a specially constructed sphere to make this work. One that lets light in at a specific point, and allows no light out. It also is built in such a way to detect when a photon hits the inside surface. Just take a look at the diagram.

So unless someone is stupid enough to try and sneak a bomb onto a plane in one of these spheres, it's not much use to the security guards.

Bose-Einstein matter was predicted decades ago.

There is also a 1986 PRL article, Diffraction of atoms by light - The near-resonant Kapitza-Dirac effect, which has as the abstract:

The Kapitza-Dirac effect is observed in the scattering of sodium atoms by a near-resonant standing-wave laser field. The data clearly show diffraction peaks of the atomic momentum transfer at even multiples of the photon momentum. Theoretical predictions for an off-resonant, adiabatic interaction with a two-state system are in reasonable agreement with the data.

It isn't clear whether a special case of the Kapitza-Dirac effect was first observed (e.g., the first time observed using an electron beam), but it seems that it wasn't the first time this effect was seen in the lab. (The press release also mentions that the basic physics demo of the double-slit experiment was Quantum Mechanics 101, when it really is High School Physics 101).

Here's a pdf article from The Industrial Physicist that talks not only about ion engines, but also other future engine concepts.

Actually, you might be a little disappointed in a certain republican, specifically our fine president.

Also, in the immediate future, publishers will likely only want to pay to digitise their bestsellers, not educational or special interest texts. But have a look on the ebooks usenet groups, and there are plenty of titles out there if you have a PC setup and aren't not that fussed about copyright - and remember, we're now talking about the impoverished here, where we're trying to educate people up to the stage where they do have the leisure and luxury to care about abstract issues like copyright.

I think you may have this backwards; the real economic benefit to publishers comes when they can do it the other way around.

A title with a huge run (in the hundreds of thousands) makes money at a resonable retail price. Publishers who can only hope to sell thousands (or hundreds, or dozens, even) of titles either make no profit or are forced to charge outrageous prices on their titles (or, often, both). Fewer units sold = more money per unit to cover the fixed costs of publication. Under the current system, the large-run mass-market books make money, while the small-run sleepers don't. Mass-market paberback titles are so cheap per unit to produce that the publishers will not even pay to have the books shipped back and re-processed. Retailers instead tear off the front cover and toss the book in the garbage/recycle bin.

With the current process for printing and selling books at a profit firmly established, don't expect publishers to move their most bankable commodities to a new, experimental technology. Rather, look for small publishers, self-publishers, and marginalized titles from the big guys to show up first on the POD machines. Only if this proves to be a widely-implemented standard will you see the bestsellers show up in this format.

What this says to me is that there is something smaller than the B meson and that the "positive" version is (now) much more prevalent than the "anti" version, such that anti-B mesons get annihilated in the sub-sub-atomic version of a matter-antimatter reaction faster than the B meson.

The experiment deals with decay, not annihilation. The B meson is made up of smaller particles, viz. a bottom quark and some other anti-quark (up, down, or strange); the B- meson is made up of an anti-bottom quark and some other quark. The other quarks (u, u-, d, d-, s, s-) are more stable than the bottom quarks; therefore, the decay of B and B- mesons is most likely caused by the decay of b and b- quarks (into charm and c- quarks). Seeing that B- mesons decay more quickly than B mesons, we infer that the b- quarks decay into c- quarks more quickly than b quarks decay into c quarks. That is, in this instance (as in the case of K mesons), the antimatter particle decays more rapidly than its matter counterpart. (We can't measure the decay rates of b and b- quarks directly because quarks are only observable in color-neutral particles, so we must observe these particles in their decay to determine the decay of these quarks.)

But as the experiment deals with decay, and not annihilation, the prevelance of one (matter/antimatter) over the other does not explain the results.

btw, here's a non-MSNBC article that deals with the issue. Here's a page that discusses the decay of b quarks in Bs (bottom-strange combination) mesons.

I'm thinking this is what they're talking about (haven't seen a mirror go up yet) http://www.aip.org/physnews/preview/1997/dpp97/sn8 7a.htm

Penning trap + diagram

There was the paper (abstract here, paper here (PDF)) mentioned in the Slashdot article here about the resilience of the 'net; crash 99% of the nodes at random and it'll still run. Which isn't bad.

Problem is of course when you crash the <1% of nodes that actually do the major routing.

Routing's getting hairier and hairier; it should really get fun once IPv6 kicks off and everyone and their dog have a squillion IP addresses each.

Just to summarize, the material has both a negative dielectric and a negative permeability. Velocity (both group velocity and phase velocity) remains sub-luminal because it is the product of the two that determines the speed of propagation.

-JS

P.S. This isn't really news anymore; the link I posted is 13 months old.

Second, people have been doing things sort of like this for a while, like the "left handed" materials.

Ng [...] finds [...] that the foaminess of spacetime leads to an uncertainty in timekeeping (the more accurate the clock, the shorter its lifetime) which in turn leads to a bound on information processing (speed and memory simultaneously) analogous to the Heisenberg bound on simultaneous measurement of momentum and position.

I'm not sure of the licensing issues, but the full journal article can be found on the Applied Physics Online web site, at this URL.

A good place to start would be this article. With quantum encryption you can determine whether there's an eavesdropper due to quantum entangled particles. Any eavesdropping will create a detectable effect on the message. There's relevant slashdot articles here and here.

The paper mentioned in the article is Journal of Applied Physics Vol. 89, No. 3, pp. 1625-- 1633, 1 February 2001. You can access the full text here if you have a subscription. Unfortunately I don't understand their technique. Can you explain it to us ?

....using the gas grill ignitor to shock your friends in the ass. >:]

Thanks Pierre and Jacques.

Actually even quantum-based security requires a a channel which is non-interceptable to work

Really? What about this then? Using entangled photons appears to actually get around this problem.

" ... the powerful percolation-based approach may help Internet architects to maximize resistance against Internet attacks, by controlling the distribution of nodes having certain numbers of connections."

You can read about the details of these wonderful devices in the Applied Physics Letters.

AnHTML version.
ASectioned HTML version
Or download thePDF.

You can read about the details of these wonderful devices in the Applied Physics Letters.

AnHTML version.
ASectioned HTML version
Or download thePDF.

You can read about the details of these wonderful devices in the Applied Physics Letters.

AnHTML version.
ASectioned HTML version
Or download thePDF.

Read it again. Materials which have the desired properties for microwaves and radio waves already exist.

If you read the abstract of his paper here, you will see he hypothesizes you could do this with optical light using silver.

Materials science is one of the fastest moving fields there is, I would not underestimate how fast this could change optics. And saying something is "just theory" completely denigrates how important an idea can be in changing a field.

If you're going to get informed on the platforms, you might as well get informed on the decisions that really matter.

The source listed at the bottom of the article Physics Review Letters (vol 85, p1674) is incorrect.

It looks like the correct source should be Physical Review Letters -- August 21, 2000 -- Volume 85, Issue 8, pp. 1642-1645

The Abstract is available here

You can download the .PDF or gziped PS version of the article for $20 US but I'm not that interested.

• quantum gravity
• understanding the nucleus
• fusion energy
• climate change
• turbulence
• glassy materials
• high-temperature superconductivity
• solar magnetism
• complexity
• consciousness

note that the definition of "physics" being used here is pretty broad. :-)

http://www.aip.org/pt/june00/current.htm

Let's see, from next year's appropriations, in millions...

Space Science Total $2,398.8
Life/Microgravity S&A Total $302.4
Earth Science Total $1,405.8
SPACE STATION $2,114.5
SPACE SHUTTLE $3,165.7

(<pre> would be a nice tag to allow here, Mr. Slash coder...)

So shuttle plus station is getting slightly more than science. I'd prefer more for science, but it's hardly nothing.

Source: American Institute o' Physics

As I understand it (IANAP) c cannot be reached by a chunk of mass because you would need an infinite amount of momentum to push anything to c ... it's an asymptope in space-time. Where relativity comes in is when gravity meets c, or meets photons travelling at the speed of light. In relativity, Einstein showed that motion has a gravitational force (relative to the object at rest on the body of motion ... which is only in motion from another frame of reference) and that gravitation bends space-time in such a way that it modifies the path of light but that, from the reference point of the photon, the path has not changed at all and it travels unaffected. The trick is that from both frames of reference, the speed of light doesn't vary.

Anyway, you might find this website to be of some help to you. The Michelson-Morley experiment is pretty famous for showing that the speed of light is constant and doesn't change with respect to oppositional or parallel motion. This experiment happened before Einstein came out with his theory but it was General Relativity that explained it.

Well, back to looking for a burger-flipping job. :grumble:

The truth about gravity is very interesting. However, my knowledge cannot be passed on to you because my life holds greater value than the dissemination of this info (from my point of view). I apologize for my selfishness, but must point out that this what society has taught me.

Search here.

Well if you really want to understand the journal article, you need to do what researchers do, a literature search. The Nature article references a Physical review letters article which has further references which you can look up. This process generally takes at least a few days (if you have access to a good research library) and an understanding of the basic concepts involved (this is why NYT doesn't reference "evanescent waves" but the Nature article does, Nature expects anyone reading the article to understand the basic concepts involved) IAAP (I am a Physicist) but this is not my area of expertise, IIRC evanescent waves are the part of the wave that enters a surface (for instance the cladding around an optical fiber) and propagates through it for a short distance rather than being reflected back into the incident medium. As to why they can't carry information the Physical review article goes into this in a little more depth, I suggest you try to read it (though it is more technical than the Nature article so might not be of much use to you but the relavent section is the last couple of paragraphs of the article.)

So it's a matter of which wall we hit first: the physical or the economic.