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do you want to add some of that to the humanoids in space acta futura article?

I looked at the wiki input on this, but I don't know what I should do. Aren't you writing the article. I definitely think there are some stuffs to pick up on the list and develop further.

Aparently very interesting, will it survive the short hype? Relevant work describing mirror charges of topological insulators and the classical boundary conditions were done by Ismo and Ari. But the two communities don't know each other and so they are never cited. Also a way to produce new things...

Thanks for noticing! Indeed, I had no idea that Ari (don't know Ismo) was involved in the field. Was it before Kane's proposal or more recently? What I mostly like is that semiconductors are good candidates for 3D TI, however I got lost in the quantum field jargon. Yesterday, I got a headache trying to follow the Majorana fermions, the merons, skyrnions, axions, and so on. Luzi, are all these things familiar to you?

Ismo Lindell described in the early 90's the mirror charge of what is now called topological insulator. He says that similar results were obtained already at the beginning of the 20th century... Ismo Lindell and Ari Sihvola in the recent years discussed engineering aspects of PEMCs (perfect electro-megnetic conductors,) which are more or less classical analogues of topological insulators. Fundamental aspects of PEMCs are well knwon in high-energy physics for a long time, recent works are mainly due to Friedrich Hehl and Yuri Obukhov. All these works are purely classical, so there is no charge quantisation, no considerations of electron spin etc. About Majorana fermions: yes, I spent several years of research on that topic. Axions: a topological state, of course, trivial :-) Also merons and skyrnions are topological states, but I'm less familiar with them.

"Non-Abelian systems1, 2 contain composite particles that are neither fermions nor bosons and have a quantum statistics that is far richer than that offered by the fermion-boson dichotomy. The presence of such quasiparticles manifests itself in two remarkable ways. First, it leads to a degeneracy of the ground state that is not based on simple symmetry considerations and is robust against perturbations and interactions with the environment. Second, an interchange of two quasiparticles does not merely multiply the wavefunction by a sign, as is the case for fermions and bosons. Rather, it takes the system from one ground state to another. If a series of interchanges is made, the final state of the system will depend on the order in which these interchanges are being carried out, in sharp contrast to what happens when similar operations are performed on identical fermions or bosons." wow, this paper by Stern reads really weired ... any of you ever looked into this?

C'mon Leopold, it's as trivial as the topological states, AKA axions! Regarding the question, not me!

just looked up the wikipedia entry on axions .... at least they have some creativity in names giving: "In supersymmetric theories the axion has both a scalar and a fermionic superpartner. The fermionic superpartner of the axion is called the axino, the scalar superpartner is called the saxion. In some models, the saxion is the dilaton. They are all bundled up in a chiral superfield. The axino has been predicted to be the lightest supersymmetric particle in such a model.[24] In part due to this property, it is considered a candidate for the composition of dark matter.[25]"

Thank's Leopold. Sorry Luzi for being ironic concerning the triviality of the axions. Now, Leo confirmed me that indeed is a trivial matter. I have problems with models where EVERYTHING is involved.

Well, that's the theory of everything, isn't it?? Seriously: I don't think that theoretically there is a lot of new stuff here. Topological aspects of (non-Abelian) theories became extremely popular in the context of string theory. The reason is very simple: topological theories are much simpler than "normal" and since string theory anyway is far too complicated to be solved, people just consider purely topological theories, then claiming that this has something to do with the real world, which of course is plainly wrong. So what I think is new about these topological insulators are the claims that one can actually fabricate a material which more or less accurately mimics a topological theory and that these materials are of practical use. Still, they are a little bit the poor man's version of the topological theories fundamental physicists like to look at since electrdynamics is an Abelian theory.

I have the feeling, not the knowledge, that you are right. However, I think that the implications of this light quantum field effects are great. The fact of being able to sustain two currents polarized in spin is a technological breakthrough.

not sure how much I can contribute to your apparently educated debate here but if I remember well from my work for the master, these non-Abelian theories were all but "simple" as Luzi puts it ... and from a different perspective: to me the whole thing of being able to describe such non-Abelian systems nicely indicates that they should in one way or another also have some appearance in Nature (would be very surprised if not) - though this is of course no argument that makes string theory any better or closer to what Luzi called reality ....

Well, electrodynamics remains an Abelian theory. From the theoretical point of view this is less interesting than non-Abelian ones, since in 4D the fibre bundle of a U(1) theory is trivial (great buzz words, eh!) But in topological insulators the point of view is slightly different since one always has the insulator (topological theory), its surrounding (propagating theory) and most importantly the interface between the two. This is a new situation that people from field and string theory were not really interested in.

guys... how would you explain this to your gran mothers?

what is great exactly ? No human beings will put a foot on the Moon, or Mars, in the next 22 yrs and more ... what an awful waste!

No. People SHOULD look at alternative views to be more informed. Criticism of areas of science is a GOOD thing, it helps science to grow. Unfortunately, when it comes to this issue, people, including ACT members have a closed mind and do not want to listen to alternative view points. But I am sure many people in the group have seen it before. Have you?

interesting guy indeed ... "Forget today's green technologies like electric cars, wind turbines, solar cells and smart grids, in other words. None meets what Mr Khosla calls the "Chindia price"-the price at which people in China and India will buy them without a subsidy. "Everything's a toy until it reaches that point," he says. I also like this one since its a bit like ACT topic selection: ""I am only interested in technologies that have a 90% chance of failure but, if they do succeed, would change the infrastructure of society in some radical way," he says." should we propose SPS to him ? :-)

one more: ""I never compute returns. If you start forecasting cash flows, you lose innovation, you lose instinct. You average yourself down to mediocrity." "I've had many more failures than successes in my life," admits Mr Khosla. "My willingness to fail gives me the ability to succeed."

Watch out!! I read quite a lot about the contribution by EPFL (apparently coordinator) and their boss, Henry Markram. From what I read, this is not really science, but mainly a PR campaign. The main motor in this project is attracting a lot of money and the main aim to do so is promising a lot of stuff that nobody will be able to deliver. Accordingly, Markram is a very controversial person in the business...

Oups, sorry! Of course I meant, "the main MEAN to do so...", but the aim justifies the means. Well, that's exactly Markram's motto, I guess.

interesting info indeed ... I though still think that the overall goal of this project, even if too ambitious for the time being is interesting, no?

It's not about interesting or not, it's about serious science or not. Also the goal of a fortune-teller is interesting, isn't it? Any description of a good science project is too ambitious, that's normal and not necessarily PR. But personally I think there is a certain limit where a science project becomes a bad SciFi thriller. This one here is a dime novel, I think. But the too ambitious is not the only point I became very doubtful. I have seen quite a number of scientists and engineers from different fields; what I read about the character and attitude of this guy just hints towards the worst case scenario. It's presumptive evidence, I know...