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LeopoldS

Macroscopic invisibility cloaking of visible light : Nature Communications : Nature Pub... - 3 views

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    and all this without magic metamaterials ...
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    Wellwellwell! I don't know how I have to complain, since I could not yet read the full article, but I'm sure I will :-).
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    It's funny to see how people get more and more humble in the desperate attempt to save their stupid ideas... At the beginning was the brave and bold aim to cloak something in free space (in a sphere or a cylinder). This requires inhomogeneous, anisotropic, magnetic materials; hopeless!! So one reduces to one polarization, now we have inhomogenous, anisotropic materials; still hopeless! At this point one downgraded the pretension: instead of cloaking in free space, we make a "carpet cloak" and hide an object behind an invisible dent in a mirror. But if that shall be continuous, we still need inhomogeneity and this is very hard. So now instead of a dent we take a cone and then it is claimed to work ... for ONE polarization. But of course the cloak can't work at all incident angles... irony of fate: everything is now made from birefringent media, the antithesis of what the metamaterials dogma was at the beginning!
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    Hi Luzi, can you please send me the paper. We are writing a project based on sulfates and carbonates, and all this BS sounds great for the introduction (The authors used Calcite as birefringent material)
LeopoldS

Golden Goal collaborates with Flamingo in conferring synaptic-layer specificity in the ... - 1 views

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    new interesting neuroscience article ... how can we learn from this for AI?
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    > how can we learn from this for AI? After reading the abstract only... it appears a bit too low-level to be relevant...
Isabelle DB

The emergent dynamics of biological systems - 3 views

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    Want to play football with paramecia?
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    Interesting lab: very young and still in building up / recruiting phase: "Our lab started officially February 2010 - and we are looking for new members! "
Luís F. Simões

Shell energy scenarios to 2050 - 6 views

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    just in case you were feeling happy and optimistic
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    An energy scenario published by an oil company? Allow me to be sceptical...
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    Indeed, Shell is an energy company, not just oil, for some time now ... The two scenarii are, in their approach, dependant of economic and political situation, which is right now impossible to forecast. Reference to Kyoto is surprising, almost out-dated! But overall, I find it rather optimistic at some stages, and probably the timeline (p37-39) is unlikely with recent events.
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    the report was published in 2008, which explains the reference to Kyoto, as the follow-up to it was much more uncertain at that point. The Blueprint scenario is indeed optimistic, but also quite unlikely I'd say. I don't see humanity suddenly becoming so wise and coordinated. Sadly, I see something closer to the Scramble scenario as much more likely to occur.
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    not an oil company??? please have a look at the percentage of their revenues coming from oil and gas and then compare this with all their other energy activities together and you will see very quickly that it is only window dressing ... they are an oil and gas company ... and nothing more
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    not JUST oil. From a description: "Shell is a global group of energy and petrochemical companies." Of course revenues coming from oil are the biggest, the investment turnover on other energy sources is small for now. Knowing that most of their revenues is from an expendable source, to guarantee their future, they invest elsewhere. They have invested >1b$ in renewable energy, including biofuels. They had the largest wind power business among so-called "oil" companies. Oil only defines what they do "best". As a comparison, some time ago, Apple were selling only computers and now they sell phones. But I would not say Apple is just a phone company.
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    window dressing only ... e.g. Net cash from operating activities (pre-tax) in 2008: 70 Billion$ net income in 2008: 26 Billion revenues in 2008: 88 Billion Their investments and revenues in renewables don't even show up in their annual financial reports since probably they are under the heading of "marketing" which is already 1.7 Billion $ ... this is what they report on their investments: Capital investment, portfolio actions and business development Capital investment in 2009 was $24 billion. This represents a 26% decrease from 2008, which included over $8 billion in acquisitions, primarily relating to Duvernay Oil Corp. Capital investment included exploration expenditure of $4.5 billion (2008: $11.0 billion). In Abu Dhabi, Shell signed an agreement with Abu Dhabi National Oil Company to extend the GASCO joint venture for a further 20 years. In Australia, Shell and its partners took the final investment decision (FID) for the Gorgon LNG project (Shell share 25%). Gorgon will supply global gas markets to at least 2050, with a capacity of 15 million tonnes (100% basis) of LNG per year and a major carbon capture and storage scheme. Shell has announced a front-end engineering and design study for a floating LNG (FLNG) project, with the potential to deploy these facilities at the Prelude offshore gas discovery in Australia (Shell share 100%). In Australia, Shell confirmed that it has accepted Woodside Petroleum Ltd.'s entitlement offer of new shares at a total cost of $0.8 billion, maintaining its 34.27% share in the company; $0.4 billion was paid in 2009 with the remainder paid in 2010. In Bolivia and Brazil, Shell sold its share in a gas pipeline and in a thermoelectric power plant and its related assets for a total of around $100 million. In Canada, the Government of Alberta and the national government jointly announced their intent to contribute $0.8 billion of funding towards the Quest carbon capture and sequestration project. Quest, which is at the f
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    thanks for the info :) They still have their 50% share in the wind farm in Noordzee (you can see it from ESTEC on a clear day). Look for Shell International Renewables, other subsidiaries and joint-ventures. I guess, the report is about the oil branch. http://sustainabilityreport.shell.com/2009/servicepages/downloads/files/all_shell_sr09.pdf http://www.noordzeewind.nl/
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    no - its about Shell globally - all Shell .. these participations are just peanuts please read the intro of the CEO in the pdf you linked to: he does not even mention renewables! their entire sustainability strategy is about oil and gas - just making it (look) nicer and environmentally friendlier
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    Fair enough, for me even peanuts are worthy and I am not able to judge. Not all big-profit companies, like Shell, are evil :( Look in the pdf what is in the upstream and downstream you mentionned above. Non-shell sources for examples and more objectivity: http://www.nuon.com/company/Innovative-projects/noordzeewind.jsp http://www.e-energymarket.com/news/single-news/article/ferrari-tops-bahrain-gp-using-shell-biofuel.html thanks.
LeopoldS

Unbound or distant planetary mass population detected by gravitational microlensing : N... - 1 views

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    dark matter :-) ?? could there be loads of them?
santecarloni

Broadband graphene polarizer : Nature Photonics : Nature Publishing Group - 0 views

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    Graphene miracles
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    Actually since this graphene hype started, being more or less a physics laic, I keep wondering how much of these promised miracles will in fact be delivered? Any chance for an expert's opinion?
Luís F. Simões

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

  • 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.
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  • * 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.
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    Sounds good!
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    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
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    interesting stuff anyone read cryptonomicon by neal stephenson? similar theme.
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    :) 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...
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    One of my colleagues has made a nice, short write-up about BitCoin: http://www.pds.ewi.tudelft.nl/~victor/bitcoin.html
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    very nice analysis indeed - thanks Tamas for sharing it!
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    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.
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    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
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    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 ...
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    @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).
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    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 ?
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    well, from 1936 to 1993 the central bank of france was owned by the state and was supposed to serve the general interest...
santecarloni

Single-cell biological lasers : Nature Photonics : Nature Publishing Group - 0 views

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    Here, we show that fluorescent proteins4, 5 in cells are a viable gain medium for optical amplification, and report the first successful realization of biological cell lasers based on green fluorescent protein (GFP).
LeopoldS

Non-mare silicic volcanism on the lunar farside at Compton-Belkovich : Nature Geoscienc... - 1 views

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    a place to land ...
pandomilla

Bioinspired self-repairing slippery surfaces with pressure-stable omniphobicity : Natur... - 3 views

  • a strategy to create self-healing, slippery liquid-infused porous surface(s) (SLIPS) with exceptional liquid- and ice-repellency, pressure stability and enhanced optical transparency. Our approach—inspired by Nepenthes pitcher plants13—is conceptually different from the lotus effect, because we use nano/microstructured substrates to lock in place the infused lubricating fluid. We define the requirements for which the lubricant forms a stable, defect-free and inert ‘slippery’ interface.
  • ts capability to repel various simple and complex liquids (water, hydrocarbons, crude oil and blood),
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    ...This slippery surface was bio-inspired by the carnivorous plant I showed you sometimes ago! I was sure it was a good idea! next time I will be quicker!!
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    Shit. I am sure that there is more to do on this. Let's have a closer look.
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    And a good lesson that it is important to proceed quickly when you have an idea and don't wait ...
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    Yes, I will see what we could do, but they really did a good job, from the biomimetic of the surface, up to the realization of the material, and the tests...
pacome delva

Orbiting standards lab could improve climate predictions - physicsworld.com - 2 views

  • Policy makers would be much better placed to combat the effects of global warming if scientists had access to accurate measurements of the Earth's radiation balance from a dedicated satellite, claims an international group of physicists.
  • it estimates that the satellite could cut a decade or more from the time needed to make useful projections of global temperature at the end of the 21st century.
pacome delva

Galaxy clusters back general relativity - 0 views

  • The Copenhagen group discovered that the redshifts agreed with the predictions of both general relativity and f(R) gravity, the theory that tries to avoid dark energy. However, the error bars on the redshifts excluded MOND and TeVeS, the theories that try to avoid dark matter.
LeopoldS

Strong plasmonic enhancement of photovoltage in graphene : Nature Communications : Natu... - 0 views

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    graphene for solar cells ... who wants to have a closer look at it?
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    Why not but I'm not sure I have the competences/background to do much...
Dario Izzo

Nobel Laureate Ivar Giaever Quits Physics Group over Stand on Global Warming - Internat... - 1 views

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    mmm .. people are making a lot of overstatments on the issue ....
pacome delva

Physics - Atoms in a lattice keep time - 0 views

  • If your wristwatch was as accurate as today’s atomic clocks, it would not gain or lose a second in 80 million years.
  • The NIST group traps and cools neutral 171Yb atoms and loads them into a one-dimensional lattice, so that about 30,000 atoms fill several hundred lattice sites.
  • Lemke et al. compare their optical lattice clock with the current standard atomic fountain clock and find that the accuracy of the Yb lattice clock potentially challenges the current standard.
Francesco Biscani

DIRECT - Wikipedia, the free encyclopedia - 0 views

  • DIRECT is a proposed alternative Shuttle-Derived Launch Vehicle architecture supporting NASA's Vision for Space Exploration, which would replace the space agency's planned Ares I and Ares V rockets with a family of launch vehicles named "Jupiter."
  • DIRECT is advocated by a group of space enthusiasts that asserts it represents a broader team of dozens of NASA and space industry engineers who actively work on the proposal on an anonymous, volunteer basis in their spare time.
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    Just read about this, it looks like an interesting example of bottom-up innovation and self-organization.
Joris _

$21 Billion Orbiting Solar Array will Beam Electricity to Earth - 0 views

  • The project, to be undertaken by a research group from 16 companies including Mitsubishi Heavy Industries Ltd, aims to spend the next four years developing the technology needed to beam the electricity produced to earth
  • not be commercially viable at today's prices
nikolas smyrlakis

Should NIAC be Revived? | NASA Watch - 0 views

  • $4 million annual budge
    • nikolas smyrlakis
       
      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?
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    about the advanced concepts institute of NASA. Found via twitter
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