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Well nVidia provides 10.000 "cores" in a single rack on thei Teslas...

remember that you were recommending its purchase already some time ago ... still strong reasons to do so?

we... the article is a bit overblown in my view ... except maybe the last paragraphs: "The collision between universe's is a variation on this theme. "The "colliding universe" scenario can be realized as a simple extension of our earlier experiments simulating the spacetime geometry in the vicinity of big bang," he says. He simulates an expanding universe using concetric rings of gold separated by a dielectric. "When the two concentric ring ("universe") patterns touch each other ("collide"), a Minkowski domain wall is created, in which the metallic stripes touch each other at a small angle," he says. Being able to recreate these exotic events in the lab is certainly interesting but it is beginning to lose its novelty. The problem is that this work is not telling us anything we didn't know--the universe behaves the same way inside a metamaterial as it does outside. What Smolyaninov needs is a way of using his exotic materials to do something interesting. In other words, he needs a killer app. Any ideas? "

well sure competitiveness is good but to verify (and that should be the case for scientific experiments) the code should be public, it would be nice to have something like bibtex for code libraries or versions used.... :) btw I fully agree that the code should go public, I had lots of trouble reproducing (reprogramming) some papers in the past ... grr

Diffcult for me to fully understand / believe in the holographic principle at macroscopical scales ... potentially it looks though as a revolutionary idea.....

never heard about it... seems interesting. At first sight it seems that it is based on fundamental principle that could lead to a new phenomenology, so that could be tested. Perhaps Luzi knows more about this ? Did we ever work on this concept ?

The paper is quite long and I don't have the time right now to read it in detail. Just a few comments: * We (ACT) definitely never did anything in this direction? But: is there a new phenomenology? I'm not sure, if the aim is just to get Einstein's theory as emergent theory, then GR should not change (or only change in extreme conditions.) * Emergent gravity is not new, also Erik admits that. The claim to have found a solution appears quite frequently, but most proposals actually are not emergent at all. At least, I have the impression that Erik is aware of the relevant steps to be performed. * It's very difficult to judge from a short glance at the paper, up to which point the claims are serious and where it just starts to be advertisments. Section 6 is pretty much a collection of self-praise. * Most importantly: I don't understand how exactly space and time should be emergent. I think it's not new to observe that space is related to special canonical variables in thermodynamics. If anybody can see anything "emergent" in the first paragraphs of section 3, then please explain me. For me, this is not emergent space, but space introduced with a "sledge hammer." Time anyway seems to be a precondition, else there is nothing like energy and nothing like dynamics. * Finally, holography appears to be a precondition, to my knowledge no proof exists that normal (non-supersymmetric, non-stringy, non-whatever) GR has a holographic dual.

Update: meanwhile I understood roughly what this should be about. It's well known that BH physics follow the laws of theormodynamics, suggesting the existence of underlying microstates. But if this is true, shouldn't the gravitational force then be emergent from these microstates in the same way as any theromdynamical effect is emergent from the behavior of its constituents (e.g. a gas)? If this can be prooven, then indeed gravity is emergent. Problem: one has to proof that *any* configuration in GR may be interpreted as thermodynamical, not just BHs. That's probably where holography comes into the play. To me this smells pretty much like N=4 SYM vs. QCD. The former is not QCD, but can be solved, so all stringy people study just that one and claim to learn something about QCD. Here, we look at holographic models, GR is not holographic, but who cares... Engineering problems...

is there any experimental or observational evidence that points to this "solution"?

Are you joking??? :D

I was a bit fast to say it could be tested... apparently we don't even know a theory that is holographic, perhaps a string theory (see http://arxiv.org/abs/hep-th/9409089v2). So very far from any test...

Luzi, I miss you!!!

Don't know if you have full text access, so here goes the quote: "Recently, Izzo et al. designed in [27] a heterogeneous asynchronous island model for DE. They considered five islands and five DE strategies (DE/best/1/exp, DE/rand/1/exp, DE/rand-to-best/1/exp, DE/best/2/exp, and DE/rand/2/exp), and studied five distributed DEs using the same DE strategy in all the islands, and a heterogeneous model with one different DE strategy in every island. As a result, the heterogeneous model is not outstanding, but performs as well as the others."

Perhaps some of ACTers will find this conference interesting... One of the talks: "Would Einstein be on Twitter? Exploring the potential and limits of Web 2.0 in science & science communication" [Edit] Oh, I see someone has already posted this link... a year ago. Anyway, if anyone of you plans to go, let me know - I'll be around ;-)

Just came back from ESOF 2010... I was on look for ACT agents undercover, but either they were not there or the cover was good enough... Anyway here's a few remarks from me (I could write a nice report... if you paid): 1) In general, to say that ESA was underrepresented on the conference as a whole is not enough (I guess ESA just failed to notice the event taking place). For instance, on the GMES presentation, ESA as such was not mentioned at all... at some point I started to wonder if ESA is actually involved in the project, but now I checked the website and apparently it is. On the other hand, GMES presentation was crap anyway, as after 1:15 of talking, I didn't gain any knowledge of what GMES is and what its contributions to the EU community will be. 2) There was a lot of talk about LHC and particle research (well, at least among those that I attended). Some of them were very good, some of them rather crap... 3) "Would Einstein be on Twitter? Exploring the potential and limits of Web 2.0 in science & science communication" talk - quite interesting, but focusing mainly on Science-to-Wide Public and Science-to-Journalists communication. Not really on Science-to-Science (as in Ariadnet). There was quite an extensive discussion with the public. You may be interested that Nature is trying to stimulate Web 2.0 communication, running blog service, but also I think a kind of social network - perhaps you'd like to have a look. In general the conclusion was that Web 2.0 is not so useful for scientific communication because practising it requires TIME (blogs, etc.) and often some professional skills (podcasts/videocasts, etc.), and scientists have neither of these. This can be run on corporation level (like ESA does actually), but then it looses the "intimate" character. 4) "How much can robots learn?" talk... very nicely presented: understandable by the wide public, but conveying the message... which is something like "we can already make the robots do stuff absolutely imp

Well, my comment was cut in half, and I don't feel like typing it again... the most important highlight from the rest is that the only presenter from ESA (ESTEC) did not show up on his talk because his department was undergoing some sort of audit on the same day :)

Fantastic comment - or better report!! thanks very much Marek! Who was the supposed no-show speaker from ESA?