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Luís F. Simões

Timelapse video of asteroid discoveries in our solar system from 1980-2010 (watch in 10... - 5 views

www.youtube.com/watch

asteroid detection solar system WISE

shared by Luís F. Simões on 13 Sep 10 - No Cached
Joris _ liked it
  • Ma Ru on 14 Sep 10
     
    Nice... Now I have a lame question: after you have discovered ~500k asteroids, all moving (I assume more or less) chaotically in that asteroid belt, how do you tell one from another?
  • ...1 more comment...
  • Joris _ on 14 Sep 10
     
    hmm, not very chaotic indeed - laws of Kepler plus some perturbations.
  • Ma Ru on 15 Sep 10
     
    That's what I thought but when presented as a green "goo" in the video, it appears rather unordered... so I guess this is just an impression evoked by a not-to-scale presentation?
  • Francesco Biscani on 19 Sep 10
     
    It depends... orbits can be chaotic if the orbital period is in a resonance with Jupiter, although such orbits are not stable. Such configurations tend to get disrupted pretty quickly (in cosmic terms :P) http://en.wikipedia.org/wiki/Kirkwood_gap
Joris _

SPACE.com -- Bigelow Aerospace Soars with Private Space Station Deals - 0 views

www.space.com/...tion-first-clients-101019.html

technology

shared by Joris _ on 20 Oct 10 - No Cached
  • A private space company offering room on inflatable space habitats for research has found a robust international market
  • A question that continues to float through the halls of NASA and the Congress: Is there a commercial market for utilizing space?
Joris _

Is It Time To Revamp Systems Engineering? | AVIATION WEEK - 1 views

www.aviationweek.com/...story.jsp

engineering

shared by Joris _ on 02 Nov 10 - No Cached
LeopoldS liked it
  • They both believe the systems engineering processes that have served the aerospace and defense community since pre-Apollo days are no longer adequate for the large and complex systems ­industry is now developing.
  • Joris _ on 02 Nov 10
     
    1) it has to actively work and produce a result that's what you intended 2) the design must be robust. 3) it should be efficient 4) it should minimize unintended consequences. "But we have to establish a formal, mathematically precise mechanism to measure complexity and adaptability . . . [where] adaptability means the system elements have sufficient margin, and can serve multiple purposes." "We need to break the paradigm of long cycles from design to product" some interesting questions....
  • ...1 more comment...
  • LeopoldS on 02 Nov 10
     
    indeed ... already hotly debated in CDF ... any suggestions in addition to what we already contributed to this (e.g. system level optimisation)
  • Joris _ on 03 Nov 10
     
    what is the outcome of the CDF study ? I think actually that optimisation is not at all the key point. As it is stressed in this news, it is robustness (points 2 and 4). This is something we should think about ...
  • Luzi Bergamin on 03 Nov 10
     
    SYSTEM OF SYSTEMS, SYSTEM OF SYSTEMS!!! :-D
Giusi Schiavone

Selective attention processes - 2 views

www.youtube.com/...NatureVideoChannel

shared by Giusi Schiavone on 27 Oct 10 - No Cached
  • Giusi Schiavone on 27 Oct 10
     
    they use invasive BCI for accessing to single neural cell on patiences with epilepsy.
  • ...1 more comment...
  • LeopoldS on 27 Oct 10
     
    scary ...
  • Giusi Schiavone on 27 Oct 10
     
    why? I think they used patients with epilepsy because they already had an implants with electrodes, for other reasons. Otherwise in normal subjects they could not obtain these results. I wonder who (among normal subject) would like to have electrodes implanted in the brain....thus they use subjects that already have an implant.
  • LeopoldS on 27 Oct 10
     
    well if I got it correctly then the had to cut and fizzle around in these brains ... always scaring, and then they claim that we have in our brains in single neurons abstract images e.g. of marilyn monroe . they speak even of Marilyn Monroe neurons :-) similarily his question "who is in control? are we in control of our neurons or our neurons in control of us? " ....
Joris _

changement_climatique__octobre_2010.pdf - 2 views

medias.lemonde.fr/...t_climatique__octobre_2010.pdf

climate change

shared by Joris _ on 28 Oct 10 - No Cached
  • Joris _ on 28 Oct 10
     
    Report commissionned by French ministry on the question of global warming and causes - in french though.
LeopoldS

Why Can't PCs Work More Like iPhones? - Bits Blog - NYTimes.com - 1 views

bits.blogs.nytimes.com/...ant-pcs-work-more-like-iphones

computing

shared by LeopoldS on 27 Feb 10 - Cached
  • LeopoldS on 27 Feb 10
     
    bye bye Francesco to your beloved command line ....
  • Francesco Biscani on 27 Feb 10
     
    I would love to see people working on touchscreens all day, orthopedics would have a field day :) Anyway, the answer to the original question is: because the JesusPhone is an appliance, a PC is not.
  • Luzi Bergamin on 01 Mar 10
     
    Luckily there is open source, so neither Steve Jobs nor NY Times decide for us what sort of OS we have to like! I'll join the "Jihad for the command line" troop!!
Francesco Biscani

The End Of Gravity As a Fundamental Force - 6 views

science.slashdot.org/...Gravity-As-a-Fundamental-Force

phy

shared by Francesco Biscani on 11 Jan 10 - Cached
LeopoldS liked it
  • Francesco Biscani on 11 Jan 10
     
    "At a symposium at the Dutch Spinoza-instituut on 8 December, 2009, string theorist Erik Verlinde introduced a theory that derives Newton's classical mechanics. In his theory, gravity exists because of a difference in concentration of information in the empty space between two masses and its surroundings. He does not consider gravity as fundamental, but as an emergent phenomenon that arises from a deeper microscropic reality. A relativistic extension of his argument leads directly to Einstein's equations."
  • ...8 more comments...
  • Dario Izzo on 12 Jan 10
     
    Diffcult for me to fully understand / believe in the holographic principle at macroscopical scales ... potentially it looks though as a revolutionary idea.....
  • pacome delva on 13 Jan 10
     
    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 ?
  • Luzi Bergamin on 13 Jan 10
     
    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.
  • Luzi Bergamin on 13 Jan 10
     
    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...
  • LeopoldS on 13 Jan 10
     
    is there any experimental or observational evidence that points to this "solution"?
  • Luzi Bergamin on 13 Jan 10
     
    Are you joking??? :D
  • pacome delva on 14 Jan 10
     
    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...
  • LeopoldS on 14 Jan 10
     
    Luzi, I miss you!!!
  • Luzi Bergamin on 14 Jan 10
     
    Leo, do you mean you liked my comment on your question more than Pacome's? Well, the ACT has to evolve and fledge, so no bullshitting anymore, but serious and calculating answers... :-) Sorry Pacome, nothing against you!! I just LOVE this Diigo because it gives me the opportunity for a happy revival of my ACT mood.
  • pacome delva on 14 Jan 10
     
    haha, today would have been great to show your mood... we had a talk on the connection between mind and matter !!
LeopoldS

Self-organized adaptation of a simple neural circuit enables complex robot behaviour : ... - 3 views

www.nature.com/...nphys1508.html

robotics

shared by LeopoldS on 19 Jan 10 - Cached
  • LeopoldS on 19 Jan 10
     
    is this really worth a nature paper??
  • Luzi Bergamin on 19 Jan 10
     
    Funny to read this question exactly from you, the all and ever fan of anything linked to bio :-) I have read worse papers in nature and in addition it's just "Nature physics", viz. "Nature garbage." Could be that they don't find enough really good stuff to publish in all their topical clones of Nature.
  • Nicholas Lan on 19 Jan 10
     
    francesco already posted this below
Tobias Seidl

Rules for Biologically Inspired Adaptive Network Design -- Tero et al. 327 (5964): 439 ... - 4 views

www.sciencemag.org/...439

BIO AI robot navigation paper

shared by Tobias Seidl on 22 Jan 10 - Cached
  • Tobias Seidl on 22 Jan 10
     
    Navigation for robtos. That's how we should have done the hybrid controller study.
  • ...3 more comments...
  • LeopoldS on 23 Jan 10
     
    and why didnt we?
  • Tobias Seidl on 25 Jan 10
     
    Because I have no clue about fungi. They are no animals. (Neither they are plants, of which I also don't have a clue.)
  • LeopoldS on 25 Jan 10
     
    so what are they then? ... and don't tell me "fungi" now ..
  • Tobias Seidl on 25 Jan 10
     
    Well, it has always been a long discussion. Fungi are according to the most recent findings definitely no plants. Since they have always been in botanic textbooks, I would assume that they were never considered animals.No fauna, no flora, no stones. Maybe they are extraterrestrials. But that wouldn't solve the questions. Maybe they are just "fungi"?
  • LeopoldS on 25 Jan 10
     
    what about then: "can we use them for space?"
Tobias Seidl

Questions Abound in Q-Fever Explosion in the Netherlands -- Enserink 327 (5963): 266 --... - 3 views

www.sciencemag.org/...266-a

shared by Tobias Seidl on 15 Jan 10 - Cached
  • Tobias Seidl on 15 Jan 10
     
    No comments
Joris _

Panel Picks 3 Finalists for ESAs Cosmic Vision M class Missions | SpaceNews.com - 3 views

spacenews.com/...ic-vision-mclass-missions.html

MAD Class_M Science Marco Polo

shared by Joris _ on 20 Jan 10 - Cached
pacome delva liked it
  • “superb from a science standpoint,” but beyond Europe’s current budget
  • There was some questioning of the cost estimate for Euclid, but at some point you have to decide: Either you don’t believe the estimates that [ESA science program managers] produced, or you assume their estimates are credible. Euclid was the one mission where costs were debated, but the consensus was to use the cost estimates presented to us.
  • pacome delva on 20 Jan 10
     
    finally cross-scale is not selected, it was the only cosmic vision mission with multi-satellites formation flying, since the concept for Xeus has changed. There is still Swarm but it's not really formation flying... So ESA is missing something here...
pacome delva

Physicists study how moral behaviour evolved - 2 views

physicsworld.com/...42540

phy ia cooperation

shared by pacome delva on 07 May 10 - Cached
  • A statistical-physics-based model may shed light on the age-old question "how can morality take root in a world where everyone is out for themselves?" Computer simulations by an international team of scientists suggest that the answer lies in how people interact with their closest neighbours rather than with the population as a whole.
  • pacome delva on 07 May 10
     
    Reminds me something... :)
  • nikolas smyrlakis on 07 May 10
     
    I check diigo for the first time since I left and my spirit is still there yeah !
Luís F. Simões

Bitcoin P2P Currency: The Most Dangerous Project We've Ever Seen - 10 views

launch.is/...dangerous-project-weve-ev.html

bitcoin p2p money disruptive

shared by Luís F. Simões on 16 May 11 - No Cached
LeopoldS liked it
  • After month of research and discovery, we’ve learned the following:1. Bitcoin is a technologically sound project.2. Bitcoin is unstoppable without end-user prosecution.3. Bitcoin is the most dangerous open-source project ever created.4. Bitcoin may be the most dangerous technological project since the internet itself.5. Bitcoin is a political statement by technotarians (technological libertarians).*6. Bitcoins will change the world unless governments ban them with harsh penalties.
  • The benefits of a currency like this:a) Your coins can’t be frozen (like a Paypal account can be)b) Your coins can’t be trackedc) Your coins can’t be taxedd) Transaction costs are extremely low (sorry credit card companies)
  • An individual with the name -- or perhaps handle -- of Satoshi Nakamoto first wrote about bitcoins in a paper called Bitcoin: A Peer-to-Peer Electronic Cash System.
  • ...1 more annotation...
  • * We made this term up to describe the “good people” of the internet who believe in the fundamental rights of individuals to be free, have free speech, fight hypocrisy and stand behind logic, technology and science over religion, political structure and tradition. These are the people who build and support things like Wikileaks, Anonymous, Linux and Wikipedia. They think that people can, and should, govern themselves. They are against external forms of control such as DRM, laws that are bought and sold by lobbyists, and religions like Scientology. They include splinter groups that enforce these ideals in the form of hacktivism, such as the takedown of the Sony Playstation Network after Sony tried to prosecute a hacker for unlocking its console.
  • Ma Ru on 17 May 11
     
    Sounds good!
  • ...9 more comments...
  • pacome delva on 18 May 11
     
    wow it's frigthening! it's the dream of every anarchist, every drug, arm, human dealer! the world made as a global fiscal paradise... the idea is clever however it will not replace real money because 1 - no one will build a fortune on bitcoin if a technological breakthrough can ruin them 2 - government never allowed parallel money to flourish on their territory, so it will be almost impossible to change bitcoin against euros or dollars
  • Nicholas Lan on 18 May 11
     
    interesting stuff anyone read cryptonomicon by neal stephenson? similar theme.
  • Luís F. Simões on 18 May 11
     
    :) yes. One of the comments on reddit was precisely drawing the parallels with Neal Stephenson's Snowcrash / Diamond Age / Cryptonomicon. Interesting stuff indeed. It has a lot of potential for misuse, but also opens up new possibilities. We've discussed recently how emerging technologies will drive social change. Whether it's the likes of NSA / CIA who will benefit the most from the Twitters, Facebooks and so on, by gaining greater power for control, or whether individuals are being empowered to at least an identical degree. We saw last year VISA / PayPal censoring WikiLeaks... Well, here's a way for any individual to support such an organization, in a fully anonymous and uncontrollable way...
  • tvinko on 18 May 11
     
    One of my colleagues has made a nice, short write-up about BitCoin: http://www.pds.ewi.tudelft.nl/~victor/bitcoin.html
  • LeopoldS on 18 May 11
     
    very nice analysis indeed - thanks Tamas for sharing it!
  • pacome delva on 20 May 11
     
    mmm I'm not an expert but it seemed to me that, even if these criticisms are true, there is one fundamental difference between the money you exchange on internet via your bank, and bitcoins. The first one is virtual money and the second one aims at being real, physical, money, even if digital, in the same way as banknotes, coins, or gold.
  • nikolas smyrlakis on 20 May 11
     
    An algorithm wanna-be central bank issuing untraceable tax free money between internet users? not more likely than the end of the world supposed to take place tomorrow, in my opinion. Algorithms don't usually assault women though !:P
  • LeopoldS on 21 May 11
     
    well, most money is anyway just virtual and only based on expectations and trust ... (see e.g. http://en.wikipedia.org/wiki/Money_supply) and thus if people trust that this "money" has some value in the sense that they can get something of value to them in exchange, then not much more is needed it seems to me ...
  • pacome delva on 23 May 11
     
    @Leopold: ok let's use the rigth words then. Bitcoin aim at being a currency ("physical objects generally accepted as a medium of exchange" from wikipedia), different than the "demand deposit". In the article proposed by Tamas he compares what cannot be compared (currencies, demand deposits and their mean of exchange). The interesting question is wether one can create a digital currency which is too difficult to counterfeit. As far as I know, there is no existing digital currency except this bitcoins (and maybe the currencies from games as second life and others, but which are of limited use in real world).
  • nikolas smyrlakis on 23 May 11
     
    well of course money is trust, and even more loans and credit and even more stock and bond markets. It all represents trust and expectations. However since the first banks 500 years ago and the first loans etc. etc., and as well the fact that bonds and currencies bring down whole countries (Greece lately), and are mainly controlled by large financial centres and (central) banks, banks have always been on the winning side no matter what and that isn't going to change easily. So if you are talking about these new currencies it would be a new era, not just a new currency. So should Greece convert its debt to bitcoins ;P ?
  • pacome delva on 23 May 11
     
    well, from 1936 to 1993 the central bank of france was owned by the state and was supposed to serve the general interest...
Luís F. Simões

When Astronomy Met Computer Science | Cosmology | DISCOVER Magazine - 1 views

discovermagazine.com/...astronomy-met-computer-science

astronomy INF data mining

shared by Luís F. Simões on 25 Jul 11 - No Cached
LeopoldS liked it
  • “That’s impossible!” he told Borne. “Don’t you realize that the entire data set NASA has collected over the past 45 years is one terabyte?”
  • The LSST, producing 30 terabytes of data nightly, will become the centerpiece of what some experts have dubbed the age of peta­scale astronomy—that’s 1015 bits (what Borne jokingly calls “a tonabytes”).
  • A major sky survey might detect millions or even billions of objects, and for each object we might measure thousands of attributes in a thousand dimensions. You can get a data-mining package off the shelf, but if you want to deal with a billion data vectors in a thousand dimensions, you’re out of luck even if you own the world’s biggest supercomputer. The challenge is to develop a new scientific methodology for the 21st century.”
  • LeopoldS on 25 Jul 11
     
    Francesco please look at this and get back wrt to the /. question .... thanks
Joris _

DailyTech - NASA Releases iPhone App - 2 views

www.dailytech.com/...article16613.htm

shared by Joris _ on 26 Oct 09 - Cached
  • The U.S. space agency has worked more diligently the past few years to better interact with the public.
  • Joris _ on 26 Oct 09
     
    what about ESA?
  • ...3 more comments...
  • LeopoldS on 26 Oct 09
     
    have already sent it as a suggestion to our com department ... btw: installed the app and its really well done!!
  • Francesco Biscani on 27 Oct 09
     
    God no, why give more taxpayers' money to the shittiest, greediest and most closed company out there??
  • LeopoldS on 27 Oct 09
     
    why "more" ... do they get any taxpayers money? answer to your question: because its the most efficient (and coolest) platform to convey your message to a larger audience with relatively little effort ... btw: just ordered a time capsule for home :-)
  • Francesco Biscani on 27 Oct 09
     
    I said "more" because we already gave them money in the form of Sophia and Atlas :) If we want to be consistent in promoting "open" efforts (open innovation, open source, open governance, etc.) we should avoid Apple like the plague. They are far far worse than Microsoft in terms of closedness, secrecy, shady market practices and vendor lock-in. Just google a bit and you will find lots of example of their behaviour.
  • nikolas smyrlakis on 28 Oct 09
     
    cant' really argue about the Apple practices, although I ve read some things. I think the NASA app is more like a news feed and nothing more. But that online crowdsourcing game we had in mind, now that would be cool in a mobile version - new mobiles also have accelerometers nowadays
Tobias Seidl

Plagiarism: Consider the Context -- Roig 325 (5942): 813 -- Science - 0 views

www.sciencemag.org/...813-c

Plagiarism

shared by Tobias Seidl on 14 Aug 09 - Cached
  • Practices such as patchwriting and authors' recycling of their previously published text should not just be regarded as questionable—they should be unequivocally classified as inappropriate scholarship
nikolas smyrlakis

Should NIAC be Revived? | NASA Watch - 0 views

www.nasawatch.com/...should_niac_be.html

niac advanced concepts nasa space

shared by nikolas smyrlakis on 12 Jun 09 - Cached
  • $4 million annual budge
    • nikolas smyrlakis
      nikolas smyrlakis on 12 Jun 09
       
      To my knowledge (readers correct me if I'm wrong) no where else within NASA do people get paid to just think very long range ideas. My question: does such a group belong in NASA and should it or something like it be revived? And if you think so, what should its highest priority be? Propulsion? Artificial gravity systems? Space Elevator?
  • nikolas smyrlakis on 12 Jun 09
     
    about the advanced concepts institute of NASA. Found via twitter
ESA ACT

A Cosmic Question: How to Get Rid Of All That Orbiting Space Junk? - WSJ.com - 0 views

online.wsj.com/...lMyQjAxMDI5MzE2MTcxMjE4Wj.html

debris

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    nice article on space debris
ESA ACT

Dumb eco-questions you were afraid to ask - 0 views

www.newscientist.com/...ns-you-were-afraid-to-ask.html

ecology recycling green environment

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    Everything you wanted to know about se... um... ecology. Very interesting, myth-busting article.
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