folk theories for folks on a ship

Raumschifferde was simply a great expedition. I love Hamburg, but more important the coffee was of superior quality. I unwittingly accepted an invitation from Matthias about speaking, and then found out that I had the keynote. It was however a fortunate set of circumstances. It so happened that the week before I was due to be in Athens where I did not have anything else to do than to work on my book, have a look at the Acropolis,  besides drinking coffee and doing a bit of Aikido with Sensei Jenny Flower. And so it was, plus a few more adventures including the preparation of this talk. By the way, most of the pics on the presentation are from Athens, the big exception being the four of the Basisbibliothek of the University of Bern. Even “le monde” of the 11th of february, used to quote Michel Foucault, was bought in Athens.

I will add a few notes to the presentation as soon as I get a few hours to work on those notes.

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Quantum leaves in fact and fiction

When one tries to wrap one’s brain around quantum mechanics chances are that the distinctions between fact and fiction blur, and on most good days that which we think to be logic eludes us. Those are the good days!

It surprised me to come across this little piece: Material witness: Quantum leaves in fact and fiction : Nature Materials : Nature Publishing Group: “Quantum coherence refers here to the way that electronically excited quantum states of the pigment chromophores called excitons maintain a correlated phase relationship for long enough to assist transfer of the excitation energy towards the reaction centre, where an electron is ejected from chlorophyll. These quantum dynamics depend on the precise nanoscale arrangement of the pigment molecules.”

Why? Oh why! I get excited about these things, passionate even. I think that what we think is logic is an insufficient (if not inadequate) guide to understanding our universe and the rules by which it plays with what we call chemistry and physics. The only trouble is that I have  yet to figure out what would complement or evolve our logic.

I have spent a few weeks around thoughts centered on nanotechnology, technology, discovery and invention because, whether you like it or not, there distinctions here that are economically relevant and that may infringe in that which we consider the common good. The common good that comprises humanity’s knowledge of the arts and sciences is what I like to call culture.

I can argue that perhaps information does not want to be free, only because information lacks a will, but when it comes to the rules by which the universe plays chemistry and physics, these are facts of nature that belong to us all. Now imagine that some multinational comes up with the idea of making a photovoltaic process that does nothing else than mimic what nature does in photosynthesis and then vaults that process in a patent. What consequences would that have? What kind of patents would be allowed? What kind of patents would not be allowed? Is the present patent system capable of adequately preserving our access to culture and knowledge?

Indeed, how the average plant leaf transfers energy from one molecular system to another is nothing short of a miracle (Ian McEwan, Solar). By the way, I have not yet read Solar, but it promises some delights in the confusion of climate change. What I find of more interest than the climate change debate itself, nanotechnology as such,  quantum mechanics, is the fact that humans will label anything which they can not comprehend with the rudiments of their logic as a miracle.

Written under a different tone but echoing some of my sentiments is another piece by Daniel Sarewitz that expresses in more details some of the ideas hinted at above.

Imitating the Sun on Earth: Fusion Reactors

Last week I visited the Wendelstein 7-X fusion device being built at the Greifswald branch of the Max Planck Institute for Plasma Physics (IPP) and was given a tour of the site in addition to an excellent presentation by former IPP director Professor Friedrich Wagner. This visit took place in the company of a group of young jurist from Germany, Austria and Switzerland who were meeting in Greifswald to discuss the topic of risk and law, or the law of risk. A report of the substantial discussion of the meeting will follow later and will be available from the NCCR Trade Regulation website. (photos)

The idea behind fusion research is to develop a power plant that releases energy by the same mechanism as the Sun does, that is, by fusing light atomic nuclei. What is special about nuclear fusion as a source of energy is that one gramme of fuel – hydrogen isotopes deuterium and tritium (produced from lithium) – generates as much energy as eleven tons of coal (90’000 kilowatt-hours of energy). When these two hydrogen isotope nuclei fuse, helium and neutrons are produced releasing large amounts of energy. In addition, the fuel itself is very abundant on earth and for all intent and purpose one may consider this to be a renewable source of energy. The energy is captured as thermal energy and converted to electrical power using turbine technology. Fusion reactors generate radioactive byproducts however these decay to background levels within one hundred years, and thus do not pose the problem of nuclear waste disposal that fission reactors do.

The sun, like other stars is a naturally occurring nuclear fusion reactor and exists not as a solid, but as a plasma. A plasma consists of electrically charged particles. The plasma of interest in the case of nuclear fusion consists of hydrogen isotope atoms that have been ionized, that is, where the electron that usually keep the atom in its neutral non ionized state has been supplied with enough energy to break loose. On earth, we have all seen plasmas in the form of neon signs or fluorescent light bulbs. Other examples include most flames, polar auroras, welding arcs, lightning and comet tails.

The first commercial commodity fusion power plant is still in the future. The two devices now under construction in Europe, ITER in France, and Wendelstein 7-X in Germany, are research devices meant to demonstrate proof of concept. In addition to these European efforts, there is the Large Helical Device (LHD) in Japan which is the largest supercoducting stellarator in the world. All of this confinement, that is the containment of the plasma is needed because like a coal fire, a fusion fire does not happen on its own, it must be ignited. To ignite a plasma and cause fusion to occur a plasma temperature of 100 million degrees is needed. To produce this kind of plasma temperature, one relies on magnetic a

Of the research fusion reactors being built, ITER is a tokamak and Wendelstein and LHD are stellerators. The difference is one of geometry. A tokamak has a magnetic toroidal confinement (like a doughnut) and the other a Möbius confinement for the plasma. In either case, the torus or the Möbius create a tube closing on itself where the plasma is confined. So, what is this plasma and why does it need confinement?

Last year a film made by the IPP on behalf of the European Fusion Development Agreement with funding from the European Union won the MIDAS Award. It is only nine minutes long and gives an entertaining and informative account on how a fusion power plat will work and what environmental properties are to be expected.