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Aurelie Heritier

New Planet Challenges Scientists - 0 views

www.local15tv.com/...hallenges-scientist-1550.shtml

shared by Aurelie Heritier on 12 Aug 13 - No Cached
  • Aurelie Heritier on 12 Aug 13
     
    NASA (WPMI) Glowing a dark magenta, the newly discovered GJ 504b, a Jupiter-sized planet with four times the mass, is posing a challenge to scientist on how giant planets are formed.
Aurelie Heritier

Team of scientists create cloned glow-in-the-dark rabbits - 3 views

www.independent.co.uk/...inthedark-rabbits-8756928.html

shared by Aurelie Heritier on 14 Aug 13 - No Cached
  • Aurelie Heritier on 14 Aug 13
     
    Fluorescent Bunnies!!!!
Paul N

Quantum gas goes below absolute zero - 4 views

www.nature.com/...es-below-absolute-zero-1.12146

science

shared by Paul N on 03 Dec 13 - No Cached
  • johannessimon81 on 04 Dec 13
     
    Quite intriguing!
  • LeopoldS on 09 Dec 13
     
    this is fantastic! If built, such systems would behave in strange ways, says Achim Rosch, a theoretical physicist at the University of Cologne in Germany, who proposed the technique used by Schneider and his team3. For instance, Rosch and his colleagues have calculated that whereas clouds of atoms would normally be pulled downwards by gravity, if part of the cloud is at a negative absolute temperature, some atoms will move upwards, apparently defying gravity4. Another peculiarity of the sub-absolute-zero gas is that it mimics 'dark energy', the mysterious force that pushes the Universe to expand at an ever-faster rate against the inward pull of gravity. Schneider notes that the attractive atoms in the gas produced by the team also want to collapse inwards, but do not because the negative absolute temperature stabilises them. "It's interesting that this weird feature pops up in the Universe and also in the lab," he says. "This may be something that cosmologists should look at more closely."
Paul N

Hacking Team Breach Shows a Global Spying Firm Run Amok | WIRED - 1 views

www.wired.com/...ws-global-spying-firm-run-amok

shared by Paul N on 08 Jul 15 - No Cached
LeopoldS liked it
  • Paul N on 08 Jul 15
     
    Few news events can unleash more schadenfreude within the security community than watching a notorious firm of hackers-for-hire become a hack target themselves. In the case of the freshly disemboweled Italian surveillance firm Hacking Team, the company may also serve as a dark example of a global surveillance industry that often sells to any government willing to pay, with little regard for that regime's human rights record. Scroll down for the commercial. :)) Funny that when I keep complaining about privacy and monitoring, people still point and laugh.
  • Alexander Wittig on 09 Jul 15
     
    And the direct link to the whole stash: https://ht.transparencytoolkit.org/ Their admin kept a plain text file with passwords on his desktop. Maybe they should have hired someone to do an audit :) More importantly, from the files it follows that this company found and exploited yet another vulnerability in Flash. So the current round of plugin/browser updates is thanks to this hack :)
  • Paul N on 09 Jul 15
     
    The vulnerability only seemed to affect some of the more recent versions. Maybe from time to time we should downgrade flash to avoid them :))
Thijs Versloot

New theory to lead to radiationless revolution - 3 views

www.anu.edu.au/...ad-to-radiationless-revolution

technology science

shared by Thijs Versloot on 01 Sep 15 - No Cached
  • Thijs Versloot on 01 Sep 15
     
    Physicists have found a radical new way to confine electromagnetic energy without it leaking away, akin to throwing a pebble into a pond with no splash. The theory could have broad ranging applications from explaining dark matter to combating energy losses in future technologies.
  • johannessimon81 on 01 Sep 15
     
    I think (but am not sure) that is related to a topic that Dirk Bouwmeester's group at Leiden University works on for a while now: "Linked and knotted beams of light" http://irvinelab.uchicago.edu/papers/nphys1056.pdf
Francesco Biscani

Apple's Mistake - 5 views

www.paulgraham.com/apple.html

shared by Francesco Biscani on 16 Jun 10 - Cached
LeopoldS liked it
  • Francesco Biscani on 16 Jun 10
     
    Nice opinion piece.
  • LeopoldS on 16 Jun 10
     
    nice indeed .... especially like: "They make such great stuff, but they're such assholes. Do I really want to support this company? Should Apple care what people like me think? What difference does it make if they alienate a small minority of their users? There are a couple reasons they should care. One is that these users are the people they want as employees. If your company seems evil, the best programmers won't work for you. That hurt Microsoft a lot starting in the 90s. Programmers started to feel sheepish about working there. It seemed like selling out. When people from Microsoft were talking to other programmers and they mentioned where they worked, there were a lot of self-deprecating jokes about having gone over to the dark side. But the real problem for Microsoft wasn't the embarrassment of the people they hired. It was the people they never got. And you know who got them? Google and Apple. If Microsoft was the Empire, they were the Rebel Alliance. And it's largely because they got more of the best people that Google and Apple are doing so much better than Microsoft today. Why are programmers so fussy about their employers' morals? Partly because they can afford to be. The best programmers can work wherever they want. They don't have to work for a company they have qualms about. But the other reason programmers are fussy, I think, is that evil begets stupidity. An organization that wins by exercising power starts to lose the ability to win by doing better work. And it's not fun for a smart person to work in a place where the best ideas aren't the ones that win."
  • Ma Ru on 16 Jun 10
     
    Poor programmers can complain, but they will keep developing applications for iPhone as long as their bosses will tell them to do so... From my experience in mobile software development I assure you it's not the pain of the programmer that dictates what is done, but the customer's demand. Even though like this the quality of applications is somewhat worse than it could be, clients won't complain as they have no reference point. And things will stay as they are: apple censoring the applications, clients paying for stuff that "sometimes just does not work" (it's normal, isn't it??), and programmers complaining, but obediently making iPhone apps...
jmlloren

Exotic matter : Insight : Nature - 5 views

www.nature.com/...index.html

nan phy

shared by jmlloren on 03 Aug 10 - Cached
LeopoldS liked it
  • jmlloren on 03 Aug 10
     
    Trends in materials and condensed matter. Check out the topological insulators. amazing field.
  • ...12 more comments...
  • Luzi Bergamin on 03 Aug 10
     
    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...
  • jmlloren on 04 Aug 10
     
    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?
  • Luzi Bergamin on 04 Aug 10
     
    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.
  • LeopoldS on 04 Aug 10
     
    "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?
  • jmlloren on 04 Aug 10
     
    C'mon Leopold, it's as trivial as the topological states, AKA axions! Regarding the question, not me!
  • LeopoldS on 04 Aug 10
     
    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]"
  • jmlloren on 04 Aug 10
     
    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.
  • Luzi Bergamin on 04 Aug 10
     
    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.
  • jmlloren on 04 Aug 10
     
    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.
  • LeopoldS on 04 Aug 10
     
    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 ....
  • Luzi Bergamin on 04 Aug 10
     
    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.
  • Dario Izzo on 04 Aug 10
     
    guys... how would you explain this to your gran mothers?
  • jmlloren on 05 Aug 10
  • LeopoldS on 07 Aug 10
     
    *you* tried *your* best .... ??
Francesco Biscani

BBC News - Study hints at dark matter action - 0 views

news.bbc.co.uk/...8508662.stm

phy

shared by Francesco Biscani on 16 Feb 10 - Cached
Ma Ru liked it
  • "We can't rule them out as being a signal but we can't conclude that they are a signal."
  • Francesco Biscani on 16 Feb 10
     
    Gotta love the scientific method :)
  • Ma Ru on 16 Feb 10
     
    Have to remember this very useful sentence...
  • pacome delva on 16 Feb 10
     
    haha
pacome delva

Supernovae put dark matter in the right place - 3 views

physicsworld.com/...41399

phy astrophysics dark_matter supernovae

shared by pacome delva on 14 Jan 10 - Cached
  • “one of the best papers I have ever seen”
  • pacome delva on 14 Jan 10
     
    Well, with these huge numerical simulation you're never sure of anything... Anyway the idea sounds quite convincing and simple.
  • Francesco Biscani on 14 Jan 10
     
    Whops, sorry for the duplicate bookmark above :)
pacome delva

Galaxy study backs general relativity - 1 views

physicsworld.com/...41948

galaxy general_relativity gravitational_lensing survey

shared by pacome delva on 16 Mar 10 - Cached
  • The observed ratio, dubbed EG, has a value of 0.39 ± 0.06. This agrees with general relativity, which predicts a value of 0.4. Crucially, the measurement rules out the tensor, vector scalar (TeVeS) model of modified gravity, which has an EG of 0.22 and does not need dark matter. The result does not, however, preclude the f(R) theory – which is more similar to general relativity and has EG values in the 0.328–0.365 range.
  • pacome delva on 16 Mar 10
     
    mmm, i wonder if this study takes into account the non linearities studied in the Ariadna on galaxies...
  • LeopoldS on 16 Mar 10
     
    Luzi: any comment?
Luzi Bergamin

Physics in a Crisis - 3 views

www.rqm.ch/physics_in_a_crisis.htm

phy LHC crackpot fun

shared by Luzi Bergamin on 30 Mar 10 - Cached
  • Luzi Bergamin on 30 Mar 10
     
    Luckily I'm far away from Geneva, but this has to be said today, when the LHC starts! No, not tiny black holes will eat us (what a nonsense!), but the supernovae energy will let LHC explode!!! Pacome, I expect you to debunk this with gratest care!
  • ...2 more comments...
  • pacome delva on 30 Mar 10
     
    wtf is this! As I read this morning in the newspaper (not even a scientific one), 1 TeV is the kinetic energy of a flying mosquito... so be careful ! It seems they already sloved every thing on this website: "At the Institute for Space Quantum Physics ISQP, it was already proved in 1991-1992 that dark matter is in magnetic fields as magnetic space quantum flux." This website is the biggest source of crackpots i have seen in a long time...! (http://www.supernovae-energy.com/)
  • Ma Ru on 30 Mar 10
     
    Come on guys, this website is hilarious! "The HAITI EARTHQUAKE (...) were impossible for the Institute for Space Quantum Physics (ISQP) to compute because on one single planet was on a common line or axis with the Sun: Venus."
  • Luzi Bergamin on 30 Mar 10
     
    Unfortunately, most information I have about the guy (Hans Lehner, a Swiss) is in German, his official homepage is http://www.rqm.ch/ According to EsoWatch he is the Swiss analogue to Dr. Mills and his Blacklight power. Lehner apparently founded a company, which should have produced a "Raum-Quanten-Motor" that -- of course -- produces energy out of nothing. The theory is based on spookey forces mediated by Lehneronen. 11 Million Swiss Franks (about 8 Million Euro) were lost when the company bankrupt. And the guy is selling new stocks on his homepage again... Lehner calls another crackpot named Oliver Crane Zweistein (from Einstein being "Onestone") and himself "Dreistein". Now he is looking for Mister or Misses Vierstein. Perhaps you should apply, good luck!!
  • Nicholas Lan on 30 Mar 10
     
    i like the first line of their supernovae energy technology document "Dear potential investor:"...
LeopoldS

BBC News - New method 'confirms dark energy' - 3 views

www.bbc.co.uk/...science-environment-13462926

shared by LeopoldS on 20 May 11 - No Cached
  • LeopoldS on 20 May 11
     
    Look at this!!
  • pacome delva on 20 May 11
     
    well, this confirms the standard cosmological model as a coherent model... however who is satisfied with a model where 96% of the content is unknown...?
ESA ACT

Glow in the Dark - 0 views

www.nature.com/...nphoton.2007.275.html

BIO Photonics

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    The ability of living organisms to generate light by bioluminescence is a fascinating phenomenon. Nature Photonics spoke to Yoriko Ando from the University of Tokyo about her recent quantitative analysis of the effect in fireflies.
ESA ACT

Experimental Observation of an Extremely Dark Material Made By a Low-Density Nanotube A... - 0 views

pubs.acs.org/...nl072369t.html

NAN optics technology

shared by ESA ACT on 24 Apr 09 - No Cached
  • ESA ACT on 24 Apr 09
     
    The integrated total reflectance from carbonnanotube arrays is three times lower than the lowest-ever reported values of optical reflectance from any material, making it the darkest man-made material ever.
ESA ACT

Forget Dark Matter: This Astrophysicist Found the Fastest Way to Board a Plane - 0 views

www.wired.com/...boarding

optimization

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    these astrophysicists are universally employable ...
ESA ACT

dark matter rap - 0 views

www.astronomy.ohio-state.edu/...silliness.html

phy fun

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    another science rap. Less musical, but very informative.
ESA ACT

BMW Gina news - His dark materials - 0 views

www.topgear.com/...2936

Technology car fun

shared by ESA ACT on 24 Apr 09 - No Cached
  • ESA ACT on 24 Apr 09
     
    Great concept!
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