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Dario Izzo

Bold title ..... - 3 views

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    I got a fever. And the only prescription is more cat faces! ...../\_/\ ...(=^_^) ..\\(___) The article sounds quite interesting, though. I think the idea of a "fake" agent that tries to trick the classifier while both co-evolve is nice as it allows the classifier to first cope with the lower order complexity of the problem. As the fake agent mimics the real agent better and better the classifier has time to add complexity to itself instead of trying to do it all at once. It would be interesting if this is later reflected in the neural nets structure, i.e. having core regions that deal with lower order approximation / classification and peripheral regions (added at a later stage) that deal with nuances as they become apparent. Also this approach will develop not just a classifier for agent behavior but at the same time a model of the same. The later may be useful in itself and might in same cases be the actual goal of the "researcher". I suspect, however, that the problem of producing / evolving the "fake agent" model might in most case be at least as hard as producing a working classifier...
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    This paper from 2014 seems discribe something pretty similar (except for not using physical robots, etc...): https://papers.nips.cc/paper/5423-generative-adversarial-nets.pdf
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    Yes, this IS basically adversarial learning. Except the generator part instead of being a neural net is some kind of swarm parametrization. I just love how they rebranded it, though. :))
Dario Izzo

IPCC models getting mushy | Financial Post - 2 views

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    why am I not surprised .....
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    http://www.academia.edu/4210419/Can_climate_models_explain_the_recent_stagnation_in_global_warming A view of well-respected scientists on how to proceed from here, that was rejected from Nature. In any case, a long way to go...
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    unfortunately it's too early to cheer and burn more coal ... there is also a nice podcast associated to this paper from nature Recent global-warming hiatus tied to equatorial Pacific surface cooling Yu Kosaka & Shang-Ping Xie Nature 501, 403-407 (19 September 2013) doi:10.1038/nature12534 Received 18 June 2013 Accepted 08 August 2013 Published online 28 August 2013 Despite the continued increase in atmospheric greenhouse gas concentrations, the annual-mean global temperature has not risen in the twenty-first century1, 2, challenging the prevailing view that anthropogenic forcing causes climate warming. Various mechanisms have been proposed for this hiatus in global warming3, 4, 5, 6, but their relative importance has not been quantified, hampering observational estimates of climate sensitivity. Here we show that accounting for recent cooling in the eastern equatorial Pacific reconciles climate simulations and observations. We present a novel method of uncovering mechanisms for global temperature change by prescribing, in addition to radiative forcing, the observed history of sea surface temperature over the central to eastern tropical Pacific in a climate model. Although the surface temperature prescription is limited to only 8.2% of the global surface, our model reproduces the annual-mean global temperature remarkably well with correlation coefficient r = 0.97 for 1970-2012 (which includes the current hiatus and a period of accelerated global warming). Moreover, our simulation captures major seasonal and regional characteristics of the hiatus, including the intensified Walker circulation, the winter cooling in northwestern North America and the prolonged drought in the southern USA. Our results show that the current hiatus is part of natural climate variability, tied specifically to a La-Niña-like decadal cooling. Although similar decadal hiatus events may occur in the future, the multi-decadal warming trend is very likely to continue with greenhouse gas
Dario Izzo

NASA Brings Earth Science 'Big Data' to the Cloud with Amazon Web Services | NASA - 3 views

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    NASA answer to the big data hype
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    "The service encompasses selected NASA satellite and global change data sets -- including temperature, precipitation, and forest cover -- and data processing tools from the NASA Earth Exchange (NEX)" Very good marketing move for just three types of selected data (MODIS, Landsat products) plus four model runs (past/projection) for the the four greenhouse gas emissions scenarios of the IPCC. It looks as if they are making data available to adress a targeted question (crowdsourcing of science, as Paul mentioned last time, this time climate evolution), not at all the "free scrolling of the user around the database" to pick up what he thinks useful, mode. There is already more rich libraries out there when it comes to climate (http://icdc.zmaw.de/) Maybe simpler approach is the way to go: make available the big data sets categorized by study topic (climate evolution, solar system science, galaxies etc.) and not by instrument or mission, which is more technical, so that the amateur user can identify his point of interest easily.
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    They are taking a good leap forward with it, but it definitely requires a lot of post processing of the data. Actually it seems they downsample everything to workable chunks. But I guess the power is really in the availability of the data in combination with Amazon's cloud computing platform. Who knows what will come out of it if hundreds of people start interacting with it.
Ma Ru

The quantum mechanics of time travel through post-selected teleportation - 3 views

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    Giving the title, I think the comment is not necessary...
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    Haha, nice article : One of the best-known versions of non-general relativistic quantum versions of time travel comes from Wheeler, as described by Feynman in his Nobel Prize lecture [16]: 'I received a telephone call one day at the graduate college at Princeton from Professor Wheeler, in which he said, "Feynman, I know why all electrons have the same charge and the same mass." "Why?" "Because, they are all the same electron!" And, then he explained on the telephone, "Suppose that the world lines which we were ordinarily considering before in time and space - instead of only going up in time were a tremendous knot, and then, when we cut through the knot, by the plane corresponding to a fixed time, we would see many, many world lines and that would represent many electrons, except for one thing. If in one section this is an ordinary electron world line, in the section in which it reversed itself and is coming back from the future we have the wrong sign to the proper time - to the proper four velocities - and that's equivalent to changing the sign of the charge, and, therefore, that part of a path would act like a positron."
Juxi Leitner

Technology Review: Blogs: arXiv blog: Physicist Discovers How to Teleport Energy - 4 views

  • He gives the example of a string of entangled ions oscillating back and forth in an electric field trap, a bit like Newton's balls. Measuring the state of the first ion injects energy into the system in the form of a phonon, a quantum of oscillation. Hotta says that performing the right kind of measurement on the last ion extracts this energy. Since this can be done at the speed of light (in principle), the phonon doesn't travel across the intermediate ions so there is no heating of these ions. The energy has been transmitted without traveling across the intervening space.
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    wonder if we can use that to power a moon base .... or on-board a SBSP satellite
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    will still have to read the actual article but am a bit sceptic if this interpretation really will hold ... what are our fundamental physicists saying about this?
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    I am not the physicist but I thought it might be interesting, from a space security point-of-view
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    Yes it seems really interesting and opens new possibilities. However this technology review article is not very good and the guy uses terms which have a precise meaning (like teleportation), which is different from the word we know... Quantum teleportation is what we use for designing quantum computers, but we are quite far from any practical applications. This energy teleportation will allow new scheme involving energy (if it is experimentally confirmed) which is very nice. However it seems this occurs in an entangled many-body system, which the only macroscopic one I know is a bose-eintein condensate (BEC). So it would mean infuse energy in the BEC by doing a measurement on one of the atom and extract it few millimeters away by doing a measurement on another atom. very far from any long distance power transmission...
pacome delva

Higgs hunters face long haul - 2 views

  • to reduce the chances of the LHC being derailed again by a similar accident, physicists at the Geneva lab have decided to run the collider at just half its design energy for the next 18-24 months.
  • Once the 7 TeV run is over, CERN will shut the LHC down in 2012 for a year or more to prepare it to go straight to maximum-energy 14 TeV collisions in 2013. This will be a complex job that will involve replacing some 10,000 superconducting magnet connections with more robust ones.
  • choosing to stay at lower energies is a big price to pay in terms of the Higgs search. "We will need more than twice the data at 7 TeV compared to that needed at 10 TeV to reach the same discovery potential," she says. "At this energy we can at best expect to exclude a Higgs with a mass between 155 and 175 GeV."
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    no Higgs boson before 2013... and a replacement of 10,000 superconducting magnet connections ! Reminds me of the the gravitational detectors... no detection before an upgrade in 2013...! There are the big announcements to make the cash flow... and reality !
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    Higgs is almost 81, so he should better invest in his health if he wants the Nobel prize... But who cares, it's another 5 years window where high-energy theorists can produce nonsense with no experimental evidence. They should be happy!
LeopoldS

Human Brain Project - Goals - 3 views

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    can we contribute in any way to this - or alternatively benefit from this research already now?
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    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...
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    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.
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    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?
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    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...
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    that bad! wow ....
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    You know me, I'm the bullshitter... You remember Kurzweil and his Singularity-nonsense. In a way this was very similar. Though I think Kurzweil and Markram are very different characters (The Singularity essentially is a religion, I can't see anything like that in Markram's claims) they seem to share an important point: they are both complete nerds that apparently never spent a single thought on the limits of science (in its English meaning) in general nor of their particular research field in specific. One may find this excusable, I don't. But even then, they make claims that the nerdest nerd must know that they are completely unrealistic and thus I just have to assume that they claim their nonsense on purpose. The reason in Markram's case clearly seems to be money. But all this does not mean that these nerds cannot produce valuable results.
LeopoldS

The Moon's mantle unveiled - 2 views

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    first science results reported in Nature (as far as I know) from the Yutu-2 and Chang'e mission .... and they look very good!
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    Sure they are very useful! It will be even better if they manage to fit the data to modeled circulation of the lunar magma ocean that was formed posterior to the "Theia" body collision with Earth. The collision was the cause of the magma ocean in the first place. The question now is how this circulation pattern of the lava-moon "froze" in time upon phase transition to solid. Because, what crystallizes last in sequence, is more rich in "incompatible" with the crystal structure, elements, we might combine data+models to predict their location. Those incompatible tracers are mainly radioactively decaying elements that produce heat (google publications about lunar KREEP elements (potassium (K), rare earth elements(REE), and phosphorus(P)). By knowing where the KREEP is: - we know where to dig for them mining (if they are useful for something, eg. Phosphorus for plants to be grown on the Moon) - we avoid planning to build the future human colony on top of radioactives, of course. The hope is that the Moon, due to lack of plate tectonics, has preserved this "signature of the freezing sequence". Let's see.
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    thanks Nasia! very interesting comment
Marion Nachon

Observation : this month, four planets aligned in the early morning sky. - 9 views

This month, some 30 minutes before the sunrise, look to the East, and if the sky is not too cloudy you will see Mercure, Venus, Mars and Jupiter very close, so close that it will be possible to hid...

http:__ciencia.nasa.gov_ciencias-especiales_09may_morningplanets_ space

started by Marion Nachon on 11 May 11 no follow-up yet
LeopoldS liked it
jaihobah

New Boson Claim Faces Scrutiny - 0 views

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    "The Atomki group has produced three previous papers on their beryllium-8 experiments - conference proceedings in 2008, 2012 and 2015. The first paper claimed evidence of a new boson of mass 12 MeV, and the second described an anomaly corresponding to a 13.45-MeV boson. (The third was a preliminary version of the Physical Review Letters paper.) The first two bumps have disappeared in the latest data, collected with an improved experimental setup. "The new claim now is [a] boson with a mass of 16.7 MeV," Naviliat-Cuncic said. "But they don't say anything about what went wrong in their previous claims and why we should not take those claims seriously." One naturally wonders, he said, "Is this value that they quote now going to change in the next four years?""
jaihobah

The Network Behind the Cosmic Web - 1 views

shared by jaihobah on 18 Apr 16 - No Cached
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    "The concept of the cosmic web-viewing the universe as a set of discrete galaxies held together by gravity-is deeply ingrained in cosmology. Yet, little is known about architecture of this network or its characteristics. Our research used data from 24,000 galaxies to construct multiple models of the cosmic web, offering complex blueprints for how galaxies fit together. These three interactive visualizations help us imagine the cosmic web, show us differences between the models, and give us insight into the fundamental structure of the universe."
santecarloni

Was a giant planet ejected from our solar system? - physicsworld.com - 0 views

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    A fifth giant planet was kicked out of the early solar system, according to computer simulations by a US-based planetary scientist. The sacrifice of this gas giant paved the way for the stable configuration of planets seen today, says David Nesvorný, who believes that the expulsion prevented Jupiter from migrating inwards and scattering the Earth and its fellow inner planets.
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    A fifth giant planet was kicked out of the early solar system, according to computer simulations by a US-based planetary scientist. The sacrifice of this gas giant paved the way for the stable configuration of planets seen today, says David Nesvorný, who believes that the expulsion prevented Jupiter from migrating inwards and scattering the Earth and its fellow inner planets.
johannessimon81

A Different Form of Color Vision in Mantis Shrimp - 4 views

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    Mantis shrimp seem to have 12 types of photo-receptive sensors - but this does not really improve their ability to discriminate between colors. Speculation is that they serve as a form of pre-processing for visual information: the brain does not need to decode full color information from just a few channels which would would allow for a smaller brain. I guess technologically the two extremes of light detection would be RGB cameras which are like our eyes and offer good spatial resolution, and spectrometers which have a large amount of color channels but at the cost of spatial resolution. It seems the mantis shrimp uses something that is somewhere between RGB cameras and spectrometers. Could there be a use for this in space?
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    > RGB cameras which are like our eyes ...apart from the fact that the spectral response of the eyes is completely different from "RGB" cameras (http://en.wikipedia.org/wiki/File:Cones_SMJ2_E.svg) ... and that the eyes have 4 types of light-sensitive cells, not three (http://en.wikipedia.org/wiki/File:Cone-response.svg) ... and that, unlike cameras, human eye is precise only in a very narrow centre region (http://en.wikipedia.org/wiki/Fovea) ...hmm, apart from relying on tri-stimulus colour perception it seems human eyes are in fact completely different from "RGB cameras" :-) OK sorry for picking on this - that's just the colour science geek in me :-) Now seriously, on one hand the article abstract sounds very interesting, but on the other the statement "Why use 12 color channels when three or four are sufficient for fine color discrimination?" reveals so much ignorance to the very basics of colour science that I'm completely puzzled - in the end, it's a Science article so it should be reasonably scientifically sound, right? Pity I can't access full text... the interesting thing is that more channels mean more information and therefore should require *more* power to process - which is exactly opposite to their theory (as far as I can tell it from the abstract...). So the key is to understand *what* information about light these mantises are collecting and why - definitely it's not "colour" in the sense of human perceptual experience. But in any case - yes, spectrometry has its uses in space :-)
Thijs Versloot

Electromagnetism generated by symmetry breaking in dielectrics - 0 views

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    Using dielectric materials as efficient EM radiators and receivers can scale down these antenna's to the chip level, reducing both weight and power consumption. The infamous internet-of-things one step closer. But could we also transmit power this way?? "In dielectric aerials, the medium has high permittivity, meaning that the velocity of the radio wave decreases as it enters the medium," said Dr Dhiraj Sinha, the paper's lead author. "What hasn't been known is how the dielectric medium results in emission of electromagnetic waves. This mystery has puzzled scientists and engineers for more than 60 years." The researchers determined that the reason for this phenomenon is due to symmetry breaking of the electric field associated with the electron acceleration The researchers found that by subjecting the piezoelectric thin films to an asymmetric excitation, the symmetry of the system is similarly broken, resulting in a corresponding symmetry breaking of the electric field, and the generation of electromagnetic radiation.
Francesco Biscani

Gamers beat algorithms at finding protein structures - 0 views

  • Foldit takes a hybrid approach. The Rosetta algorithm is used to create some potential starting structures, but users are then given a set of controls that let them poke and prod the protein's structure in three dimensions; displays provide live feedback on the energy of a configuration. 
  • By tracing the actions of the best players, the authors were able to figure out how the humans' excellent pattern recognition abilities gave them an edge over the computer.
  • Humans turn out to be really bad at starting from a simple linear chain of proteins; they need a rough idea of what the protein might look like before they can recognize patterns to optimize. Given a set of 10 potential structures produced by Rosetta, however, the best players were very adept at picking the one closest to the optimal configuration.
  • ...1 more annotation...
  • The authors also note that different players tended to have different strengths. Some were better at making the big adjustments needed to get near an energy minimum, while others enjoyed the fine-scale tweaking needed to fully optimize the structure. That's where Foldit's ability to enable team competitions, where different team members could handle the parts of the task most suited to their interests and abilities, really paid off.
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    Some interesting ideas for our crowdsourcing game in here.
Luís F. Simões

Picbreeder: Collaborative Interactive Art Evolution (Genetic Art) - 1 views

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    Following up on our coffee-time discussion, here's an Evolutionary Algorithm where you are the fitness function, and evolution is guided by your subjective artistic sense. Start from scratch, or pick an existing image in the database, and start evolving. At every generation, you are presented with the individuals/images in the population. Pick the ones you like. Those will be the parents from which the next generation will be bred. Repeat, repeat... where do you get to? If you want to learn more about the science behind this, check the tutorial below by Kenneth Stanley, who is also this site's supervisor: http://dx.doi.org/10.1145/1830761.1830920
pacome delva

[1012.1194] Does an atom interferometer test the gravitational redshift at the Compton ... - 0 views

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    Here is a probably definite answer to the strong polemics around the test of gravitational redshift with atom interferometers, which would be far better than the one done by ACES/PHARAO. Read the abstract it's very ACT like, Luzi should like it :) The original Nature paper is the one of Muller, Peters and Chu (the nobel and secretary of energy in the US): http://www.nature.com/nature/journal/v463/n7283/full/nature08776.html
jcunha

Accelerated search for materials with targeted properties by adaptive design - 0 views

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    There has been much recent interest in accelerating materials discovery. High-throughput calculations and combinatorial experiments have been the approaches of choice to narrow the search space. The emphasis has largely been on feature or descriptor selection or the use of regression tools, such as least squares, to predict properties. The regression studies have been hampered by small data sets, large model or prediction uncertainties and extrapolation to a vast unexplored chemical space with little or no experimental feedback to validate the predictions. Thus, they are prone to be suboptimal. Here an adaptive design approach is used that provides a robust, guided basis for the selection of the next material for experimental measurements by using uncertainties and maximizing the 'expected improvement' from the best-so-far material in an iterative loop with feedback from experiments. It balances the goal of searching materials likely to have the best property (exploitation) with the need to explore parts of the search space with fewer sampling points and greater uncertainty.
santecarloni

Getting to the froth of the matter - physicsworld.com - 1 views

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    Whether it is the frothy milk on your cappuccino, the soapy suds in your bath or the large-scale structure of the universe, foams have intrigued physicists for many years. Now, for the first time in a lab, an international group of scientists has made the Weaire-Phelan foam - which physicists believe is the lowest-energy structure for a foam formed of equal-volume bubbles.
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    Does this mean that there is foam that is non regular that can have even less energy structure? "which physicists believe is the lowest-energy structure for a foam formed of equal-volume bubbles."
Luís F. Simões

NASA Goddard to Auction off Patents for Automated Software Code Generation - 0 views

  • The technology was originally developed to handle coding of control code for spacecraft swarms, but it is broadly applicable to any commercial application where rule-based systems development is used.
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    This is related to the "Verified Software" item in NewScientist's list of ideas that will change science. At the link below you'll find the text of the patents being auctioned: http://icapoceantomo.com/item-for-sale/exclusive-license-related-improved-methodology-formally-developing-control-systems :) Patent #7,627,538 ("Swarm autonomic agents with self-destruct capability") makes for quite an interesting read: "This invention relates generally to artificial intelligence and, more particularly, to architecture for collective interactions between autonomous entities." "In some embodiments, an evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy." "In yet another aspect, an autonomous nanotechnology swarm may comprise a plurality of workers composed of self-similar autonomic components that are arranged to perform individual tasks in furtherance of a desired objective." "In still yet another aspect, a process to construct an environment to satisfy increasingly demanding external requirements may include instantiating an embryonic evolvable neural interface and evolving the embryonic evolvable neural interface towards complex complete connectivity." "In some embodiments, NBF 500 also includes genetic algorithms (GA) 504 at each interface between autonomic components. The GAs 504 may modify the intra-ENI 202 to satisfy requirements of the SALs 502 during learning, task execution or impairment of other subsystems."
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