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The unfortunate conclusion is that there is no magic bullet (solar, nuclear, wind, biomass) to replace fossil fuel at this time without major technological advances or environmental compromises.

Oh yea, we're running out of fossil fuel too. I feel screwed.

This article in Physics Today discusses the huge budget that CERN operates within as well as some rather large cost overages. So, put some cash in that birthday card!

The September issue of Physics Today also had a GLAT insert. I guess Google's trying for all sorts of backgrounds...

German lab wins linear collider contest

Particle physicists have chosen to base the proposed International Linear Collider on superconducting technology developed by an international collaboration centred on the DESY lab in Germany. The superconducting approach was chosen by an international panel ahead of a rival technology developed at Stanford in the US and the KEK lab in Japan. The eagerly-awaited decision was announced at the International Conference on High Energy Physics in Beijing today.

The 30-km-long International Linear Collider (ILC) will collide electrons and positrons together at energies of at least 500 billion electron volts. Particle physicists will use the ILC to make detailed studies of the Higgs boson and any other new particles, such as supersymmetric particles, that might be discovered at the Large Hadron Collider (LHC). It is envisaged that the ILC will turn on by around the middle of the next decade, about eight years after the start up of the LHC, which is currently being built at CERN in Geneva.

Is this the answer to God, the universe and all that?

Physicists plan £3bn experiment in a 20-mile long tunnel

They call it the God particle: a mysterious sub-atomic fragment that permeates the entire universe and explains how everything is the way it is. Nobody has ever seen the God particle; some say it doesn't exist but, in the ultimate leap of faith, physicists across the world are preparing to build one of the most ambitious and expensive science experiments the world has ever seen to try to find it.

ITER Impasse Illustrates Challenge of Site Selection

...indeed, site selection is often a thorny matter, even for scientific projects not as costly or international as ITER or the next-generation linear collider.

Just one example which I remember from the article. To supply 10% of the current US energy consumption from solar cells, one would need enough collectors with an area equal to the state of Massachusetts. We need to rethink our whole life style. Low cost energy fueled the economic boom of the last two centuries. The party is over. We are near the worldwide peak in oil production. See Hubbert Peak. As this is happening, China, India and other developing countries are increasing thier consumption.

We have enough coal to last a century or so, but we cannnot afford to put that much carbon dioxide into the air with making global warming totally intolerable.

If you think this is far into the future, check the current price of oil. Not only in dollars but in instability. While I do not think that oil is our chief reason for being in Iraq, it is obvious that if Saddam Hussein's chief export had been pistachio nuts, we would not be there.

"The Earth is the cradle of the mind, but one cannot live
forever in the cradle.". Konstantin Tsiolkovsky (1857 -- 1935)

Ever heard of the Matthew effect? It refers to how once someone achieves a certain level of accomplishment, people will attribute things to them whenever they don't know who really came up with them. It happens with Einstein, it happens with Feynman, and it also seems to happen an awful lot with Clarke.

I wonder what George O. Smith would make of it (Google for him if you don't know who he is).

There's another article on the subject in this month's issue of Physics Today: DOE Warms to Cold Fusion

The problem he addresses is that generally the research and university bureacracy has promoted a ``publish or perish'' mentality, where it's not the quality of work (or how often a work is cited) but how many papers are published that earns a researcher respect (or more earnings, grants, etc.). He illustrates a engineering dean that published on average a paper per week for a one year period. Admittedly, I suspect that most of the papers were actually written by graduate students or post-docs, but it does highlight that how much of that prolific output was new or novel, much less interesting!

Perhaps, going to a author-pays system may have some beneficial side-effects of reducing the amount of cruft that passes for a research paper nowadays. An author would have to balance his need to publish with his resources. Is the content worth it?

I no longer do physics (I'm a software developer now) because I could see the trend that it didn't matter what you wrote, but that you wrote a lot of it. I still toy with the idea of going back and doing some novel research. However, if I do, I intend to publish it on my own website, since I have no need to pad my resume' with a long list of publications, I would just want to get the results out there and indexed by google or other search engines, so anyone who cares and is looking could get instant access to it.

For those who are concerned about this concept of author-pays limiting the exposure of unknown or young researchers, they would have this option available to them also of posting their own work and letting their pool of peers discover them. If their work is truly unique and well done, then their standing will increase.

The Original article appeared in Physics Today, in November 2002.

Kadanoff both discuss the strong points of the book:

First, it is an excellent pedagogical tool for introducing a reader, even one who has no knowledge of advanced mathematics, to some of the concepts of modern computer science, mathematics, and physics. [...] This is a tour de force of clarity and simplicity.

But Kadanoff also points out several weaknesses:

However, the reporting of history is spotty and sometimes quite weak. [...] From my reading, I cannot support the view that any "new kind of science" is displayed in Wolfram's new book. I see no new kinds of calculations, no new analytic theory, and no comparison with experiment.

Kadanoff both discuss the strong points of the book:

First, it is an excellent pedagogical tool for introducing a reader, even one who has no knowledge of advanced mathematics, to some of the concepts of modern computer science, mathematics, and physics. [...] This is a tour de force of clarity and simplicity.

But Kadanoff also points out several weaknesses:

However, the reporting of history is spotty and sometimes quite weak. [...] From my reading, I cannot support the view that any "new kind of science" is displayed in Wolfram's new book. I see no new kinds of calculations, no new analytic theory, and no comparison with experiment.

There is an excellent recent article on this subject, including information about melting of the Arctic Ocean ice and the Younger Dryas etc. in the latest issue of Physics Today

Doing a Google search for "Ophiocoma wendtii optical" came up with loads of articles about this, mostly similar, but some better than others.

A good one is from Physics Today.

Looking at the photomicrograph, you would never think "perfect lens". There are a bunch of bumps in a pretty random orientation. They can't be all focussing on the same spots.

While orienting the calcite crystals with the birefringent axis parallel to the optical axis so you don't get double images is a nice trick, Bell Labs is not going to be making their lenses from burefringent materials, so that trick won't be much use to them.

The other trick, using the "double-lens shape that closely resembles the shapes proposed in the 17th century by Descartes and Huygens to minimize spherical aberrations" is also nice, it would seem we have known how to do that for some time. (Aren't those two guys getting kind of old?)

I would speculate that the critter builds the lenses, and then the nerve cells and photosensitive pigments migrate to where the lens focuses the light. It might also modify the lenses as they grow, using feedback from the nerve cells. Perhaps Bell Labs can use similar feedback to get their optics the way they want them.

Aside from light gathering, it looks to me like this trick can work backwards also. You can economize on pigment containing cells by placing them only at the focus of the lenses. Now you can camouflage yourself by changing only those small spots to match your environment.

It might interest some to know that physicists are thinking a lot about grid computing, especially those who use computation heavily, such as numerical relativists and fluid dynamicists. An interesting article appeared last year in Physics Today. Let's hope that the academic community's tradition of openness takes root in the Grid.

I think maybe PhysicsGenius may not be 100% accurate, but I don't think he's trolling.

Here's a quote from an article claiming that this quote was a response from a patent officer about the patent application from Leo Szilard, which was applied for in 1928:

"Patents can be given only for inventions that permit a commercial use. However, the submitted procedure apparently has only a scientific value. Whether, in accordance with the invention, any commercially useful material can be produced by accelerating artificially- produced positively-charged corpuscles, appears from our present knowledge ruled out. In the whole application, no hint is found that the applicant has produced, or can produce, such material. Obviously the yield would be so tiny, as with atomic disintegration from the natural alpha rays of radioactive substances, that even in the future the prospect of using the invention in commerce has the highest degree of improbability.

So it was initially rejected, maybe not for the same reason the parent though, but the patent office gave him a hard time about getting the parent.

Moderators, please mod the parent of my post down as a troll. You can mod me as informative though ;)

It is the hunch that usually leads scientists to study the phenomena/theories in question in the first place. The hard part is devising an experiment to prove/disprove what you're looking for without too many intervening factors that can get in the way. In fact, sometimes just coming up with the experiment itself is worthy of a Nobel Prize.

But scientists should NEVER EVER fake data, no matter HOW STRONGLY they believe they are right. If they're that sure, then they can publish all the theoretical articles they want. But NEVER publish fraudulent data as true. Science is about truth, truth is about absolute, not about hunches. That's why scientists do (or should, if they don't shy away from it) report estimated uncertainties for all experimentally-determined values and data points. If scientists didn't adhere to these lofty expectations, one wouldn't be able to believe any of the journals, which would be a major setback for all fields of science. If you had inherent mistrust of scientists, then science would become just like politics.

I dont know what he was working on, but I would like to give the guy the benifit of the doubt until I can read the report and experimental data.

Sorry, this guy WAS given the benefit of the doubt for many years. His results were irreproducible, which as you know, is one of the main characteristics of science. Everything must be reproducible. He claimed to grow Aluminum Oxide films that could withstand far greater electric fields before breaking down than anyone else on the planet, which is odd considering people mimicked his exact sputtering/growth techniques. For years nobody could reproduce any of his experiments. Much of the discord boiled down to a specific sputtering chamber Schon had back in Germany, where he claimed he was able to grow his thin films. Eventually Schon tried to regrow some films again in this chamber, and said he was unable to repeat his earlier work.

I worked in a physics lab this past summer where nearly every day at lunchtime the professor (Dr. Michael Tinkham, who's rather reknowned in superconductivity circles) would hold up a copy of Physics Today with a picture of Schon and warn us of the consequences of abandoning truth in favor of increased publications.

What Prof. Tinkham pointed out to us is that Schon became something of a minor deity in the realm of experimental physics, getting significant publications, usually quite often in the top physics journals such as Nature, Science, Physical Review, etc. The problem was that he soon had a reputation of greatness to maintain, so he may have gotten a little clumsy regarding data acquisition and analysis, in favor of keeping his astonishing rate of publications steady.

Eventually, things caught up to him. I'm not sure how much of his questionable work was little details that slipped though his fingers, how much was semi-conscious oversight, and how much was flat-out fabrication and fraud. But after he was caught then all his work became suspect.

The worst thing he did was re-use a dataset entirely, claiming it was a plot of something else, and left the exact same noise spurs and other anomalies.

Usually it's rare to find such blatant scientific fraud, but there was another recent fraud.

At least he's not moving the Lab's money into offshore shell companies to show earnings.

Sure, and at least he's also not killing people. But in the realm of science, what he's done is destroy the credibility that scientists strive for, and even NEED to be respected for. It's great that he's been caught, and hopefully it'll be a lesson to any up-and-coming experimentalists that no matter how much you believe in your theories, you have a committment to truth.

Maybe there should be some kind of hippocratic oath for scientists, that would be cool.

http://www.physicstoday.org/vol-55/iss-9/p55.html

Not to mention the sort of perpetual game of "who's the smartest" that takes the place of constructive dialog at all levels of physics discourse. Nobody at physics seminars actually understands more than about the first 20% of a talk, but no one will speak up for fear of looking like an idiot. Some physicists are very adept at putting together a few keywords from a talk that they didn't understand and asking a question that makes them look smart. The presenter, if he's "good", will repond with some more key words that the questioner will pretend to understand. But if the presenter doesn't have an answer, or hasn't heard of some theory or thought about how it would apply to his work, then he's the one that's stupid.

What put things in perpective for me was a book
by Martin J. Rees called "Just Six Numbers : The Deep Forces that Shape the Universe".

We, as a race, have a lot of work to do.

Augustz is certainly correct. Hydrogen is not free. Indeed, 90% of the hydrogen produced now is made through steam reforming of hydrocarbons, which produces carbon dioxide as a biproduct, and wastes 30% of the energy.

A much better way to produce hydrogen is through the hydrolysis of water (the reverse reaction to what a fuel cell does), which requires an emissions-free source of electricity. Believe it or not, nuclear power is becoming safer with every generation. Another alternative is direct hydrolysis through solar semiconductors that can split water directly to hydrogen and oxygen. A review by Nate Lewis in last December's Nature (article not available on the web, but 414, 569, 2001) talks about new work in In/Ni doped TiO2 that have yields as high as 1%.

This article at Physics Today has a good discussion of many of the topics. Unfortunately, the excellent follow-up articles on hydrogen fuel and nuclear power are not availble on the web.

I forget which novel I read it from (it was years ago), but there was a sci-fi author (Asimov?) who put forth the idea that maybe there could be an intelligent life form that is electro-magnetic based

What the letters make clear is that Bohr felt very threatened by Heisenburg's visit and that he assumed that Heisenburg would be working to create a Nazi A-bomb.

What will never be known is what Heisenburg's intent actually was. Clearly his post-war statements should be viewed with suspicion, but, to give him the benefit of the doubt, he claimed to have been misunderstood by Bohr because he was afraid that the SS was spying on them, which is certainly a possibility.

I am working in the MEMs area these days. So here are some shameless plugs.

Here
is an general interest article from the group in which I work with some details oriented towards these types of mesoscopic MEMs.

Here
is a neat picture of a Mesoscopic MEMs device (an acceleratometer resting on top the middle part of the "8" in a 1998 penny.

And though my research at Berkeley wasn't MEMS oriented, Berkeley MEMS is pretty active. Here is a link to that.

As the article points out, MEMS are finding applications in cell phones because it is easy to make very small RF filters using inertial effects to provide inductive-like impedences. (In the past, the inductive like parts of a cell-phone filter would either be done with spiral inductors, which are unwieldly or via other microwave circuit voodoo.)

However, beyond cell phones is a grab bag of MEMs applications already at or beyond the prototype stage:
- Car air bag detectors (the above accelerometer)
- Laser gyroscopes
- Projection displays (pixel mirrors arrays)
- Optical fiber switches
- Medical applications (microfluidics, bio-chips, ...)
- Remote sensing (minaturized microphones, or in the future, smart dust)

Enjoy
Kevin

I am working in the MEMs area these days. So here are some shameless plugs.

Here
is an general interest article from the group in which I work with some details oriented towards these types of mesoscopic MEMs.

Here
is a neat picture of a Mesoscopic MEMs device (an acceleratometer resting on top the middle part of the "8" in a 1998 penny.

And though my research at Berkeley wasn't MEMS oriented, Berkeley MEMS is pretty active. Here is a link to that.

As the article points out, MEMS are finding applications in cell phones because it is easy to make very small RF filters using inertial effects to provide inductive-like impedences. (In the past, the inductive like parts of a cell-phone filter would either be done with spiral inductors, which are unwieldly or via other microwave circuit voodoo.)

However, beyond cell phones is a grab bag of MEMs applications already at or beyond the prototype stage:
- Car air bag detectors (the above accelerometer)
- Laser gyroscopes
- Projection displays (pixel mirrors arrays)
- Optical fiber switches
- Medical applications (microfluidics, bio-chips, ...)
- Remote sensing (minaturized microphones, or in the future, smart dust)

Enjoy
Kevin

You are right in the sense that today the speed of light in vacuum is a defined constant (299 792 458 m/s). The same holds true for the second, which makes the meter a derived unit. There was an interesting article on length measurements in the March 2000 issue of Physics Today.

I mean, they have those traces-printed-on-plastic ribbon cables connecting things like keyboards and calculator screens to components. And printer heads in inkjets.

Flex's are made using a similar process to that used to make printed circuit board. A layer of copper is stuck to a sheet of plastic and then photo etched. This is cheap but not as cheap as a normal printing process.

Plus, we have alloys which can be deposited on substrates a micron-layer at a time.

This can be done (crisp packets for example (sorry - chip packets for you yanks)) but most processes require high temperatures which don't do much good to a layer of plastic.

How tough is it to dope conducting inks with Gallium-Arsenide? (Or whatever).

Physics Today have an article about the University of Cambridge printing transistors using ink jet printers. Conducting inks are not unusual - indeed most mass produced PCBs are put together with screen printed solder paste. Its a bit of a step to call this an ink but it gives you an idea of what's possible.

Why the heck hasn't this technology been around for a decade or more? It doesn't seem so much like an advance as it does a, "They finally got off their asses and assembled the stupid thing."

The devel is in the detail. Sure I can demonstrate printing to you using some chimney soot and half a potato. Its quite a bit harder to produce a 100,000 copies of a newspaper (including those AOL CD's) for just a few pence. Development always takes many times longer than you think and far more money.

The comments I've seen all seem oriented to nanoscopic devices. That technology is still in blue sky phase (lots of potential, but nobody really knows what to do with it and it is still not practical for large scale manufacturing). Mesoscopic MEMs (devices on the order of microns in size instead of angstroms) are already used in commerical products. In fact, chances are, you already own a few and didn't even know it.

Here is an article with some details oriented towards mesoscopic MEMs.

Here is a neat picture of a Mesoscopic MEMs device.

(Bias warning: the supervisor of my research group was co-author of this article.)

Kevin

The comments I've seen all seem oriented to nanoscopic devices. That technology is still in blue sky phase (lots of potential, but nobody really knows what to do with it and it is still not practical for large scale manufacturing). Mesoscopic MEMs (devices on the order of microns in size instead of angstroms) are already used in commerical products. In fact, chances are, you already own a few and didn't even know it.

Here is an article with some details oriented towards mesoscopic MEMs.

Here is a neat picture of a Mesoscopic MEMs device.

(Bias warning: the supervisor of my research group was co-author of this article.)

Kevin

There was a good profile (well, I would say that as I wrote it :->) on Physics Today about Goldin and where he sees NASA going. You can read it here.

How scattering can create additional usable channels, from the current Physics Today:

http://physicstoday.org/pt/vol-54/iss-9/p38.html

The article focuses on one piddly part of quantum crypto. It's more powerful than it reveals, as this /. thread and it's related article discuss.

This article has a few more facts about this technology, and its references are from journals like "Science" and "Applied Physics Letters" and "Chemical Review," so you can do some in-depth research if you wish. It's not so complicated that the layman could not read it, and it has some information not covered in the howstuffworks.com article. I did like some of the pictures in the howstuffworks.com article.

The electron mobility in polymers is MUCH lower than Si (a slow semiconductor), a fact that is mentioned in the article, but glossed over on this page. Overclocking these guys still won't get you very far.

One thing not mentioned is the short shelf life of these things. They tend to degrade in days to weeks, depending on the material.

I could go on, but I won't. I'm just glad to see this finally out in the popular media.

Thanks; that's much more credible.

Two corrections to my original post: GRAB's sigint role was declassified in 1998, and the correct URL has no space.

I just bought a drum of 50km of fiber optic and this evening i'll blow my tv's tube to get a photon source. The rig seems easy to set up for any decent overclocker d00d.
I will start a souceforge page for the project and if enough developers join soon we'll have: "ssh -c B92" and "ssh -c BB84" :)
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