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santecarloni

Has 'new physics' been found at CERN? - physicsworld.com - 1 views

physicsworld.com/...47844

LHC Phy science

shared by santecarloni on 18 Nov 11 - No Cached
LeopoldS liked it
  • santecarloni on 18 Nov 11
     
    Physicists working on the LHCb experiment at the CERN particle-physics lab have released the best evidence yet for direct charge-parity (CP) violation in charm mesons....While more data must be analysed to confirm the result, the work could point to new physics beyond the Standard Model and help physicists understand why there is more matter than antimatter in the universe.
  • LeopoldS on 22 Nov 11
     
    lot of new physics this year ...
jmlloren

Why starting from differential equations for computational physics? - 1 views

www.sciencedirect.com/...S0021999113005548

INF PHY

shared by jmlloren on 02 Dec 13 - No Cached
LeopoldS liked it
  • jmlloren on 02 Dec 13
     
    "The computational methods currently used in physics are based on the discretization of differential equations. This is because the computer can only perform algebraic operations. The purpose of this paper is to critically review this practice, showing how to obtain a purely algebraic formulation of physical laws starting directly from experimental measurements."
Isabelle Dicaire

Statistical physics offers a new way to look at climate - 2 views

www.sciencedaily.com/...130305145807.htm

physics climate

shared by Isabelle Dicaire on 07 Mar 13 - No Cached
  • Isabelle Dicaire on 07 Mar 13
     
    New Earth climate model based on statistical physics and available on the App Store !
  • LeopoldS on 10 Mar 13
     
    not overly intuitive ...
LeopoldS

Physicists twist water into knots : Nature News & Comment - 3 views

www.nature.com/...twist-water-into-knots-1.12534

mathematics

shared by LeopoldS on 01 Apr 13 - No Cached
  • LeopoldS on 01 Apr 13
     
    More than a century after the idea was first floated, physicists have finally figured out how to tie water in knots in the laboratory. The gnarly feat, described today in Nature Physics1, paves the way for scientists to experimentally study twists and turns in a range of phenomena - ionized gases like that of the Sun's outer atmosphere, superconductive materials, liquid crystals and quantum fields that describe elementary particles.

    Lord Kelvin proposed that atoms were knotted "vortex rings" - which are essentially like tornado bent into closed loops and knotted around themselves, as Daniel Lathrop and Barbara Brawn-Cinani write in an accompanying commentary. In Kelvin's vision, the fluid was the theoretical 'aether' then thought to pervade all of space. Each type of atom would be represented by a different knot.

    Related stories
    Solar magnetism twists braids of superheated gas
    Electron microscopy gets twisted
    Topological insulators: Star material
    More related stories
    Kelvin's interpretation of the periodic table never went anywhere, but his ideas led to the blossoming of the mathematical theory of knots, part of the field of topology. Meanwhile, scientists also have come to realize that knots have a key role in a host of physical processes.
santecarloni

Coherent Schrödinger's cat still confounds - physicsworld.com - 1 views

physicsworld.com/...47944

schrödinger cat phy

shared by santecarloni on 29 Nov 11 - No Cached
  • santecarloni on 29 Nov 11
     
    The famous paradox of Schrödinger's cat starts from principles of quantum physics and ends with the bizarre conclusion that a cat can be simultaneously in two physical states - one in which the cat is alive and the other in which it is dead. In real life, however, large objects such as cats clearly don't exist in a superposition of two or more states and this paradox is usually resolved in terms of quantum decoherence. But now physicists in Canada and Switzerland argue that even if decoherence could be prevented, the difficulty of making perfect measurements would stop us from confirming the cat's superposition.
Guido de Croon

Will robots be smarter than humans by 2029? - 2 views

robohub.org/be-smarter-than-humans-by-2029

AI

shared by Guido de Croon on 10 Mar 14 - No Cached
  • Guido de Croon on 10 Mar 14
     
    Nice discussion about the singularity. Made me think of drinking coffee with Luis... It raises some issues such as the necessity of embodiment, etc.
  • ...9 more comments...
  • Luís F. Simões on 12 Mar 14
     
    "Kurzweilians"... LOL. Still not sold on embodiment, btw.
  • Ma Ru on 12 Mar 14
     
    The biggest problem with embodiment is that, since the passive walkers (with which it all started), it hasn't delivered anything really interesting...
  • Paul N on 13 Mar 14
     
    The problem with embodiment is that it's done wrong. Embodiment needs to be treated like big data. More sensors, more data, more processing. Just putting a computer in a robot with a camera and microphone is not embodiment.
  • Marcus Maertens on 14 Mar 14
     
    I like how he attacks Moore's Law. It always looks a bit naive to me if people start to (ab)use it to make their point. No strong opinion about embodiment.
  • johannessimon81 on 14 Mar 14
     
    @Paul: How would embodiment be done RIGHT?
  • Guido de Croon on 16 Mar 14
     
    Embodiment has some obvious advantages. For example, in the vision domain many hard problems become easy when you have a body with which you can take actions (like looking at an object you don't immediately recognize from a different angle) - a point already made by researchers such as Aloimonos.and Ballard in the end 80s / beginning 90s. However, embodiment goes further than gathering information and "mental" recognition. In this respect, the evolutionary robotics work by for example Beer is interesting, where an agent discriminates between diamonds and circles by avoiding one and catching the other, without there being a clear "moment" in which the recognition takes place. "Recognition" is a behavioral property there, for which embodiment is obviously important. With embodiment the effort for recognizing an object behaviorally can be divided between the brain and the body, resulting in less computation for the brain. Also the article "Behavioural Categorisation: Behaviour makes up for bad vision" is interesting in this respect. In the field of embodied cognitive science, some say that recognition is constituted by the activation of sensorimotor correlations. I wonder to which extent this is true, and if it is valid for extremely simple creatures to more advanced ones, but it is an interesting idea nonetheless. This being said, if "embodiment" implies having a physical body, then I would argue that it is not a necessary requirement for intelligence. "Situatedness", being able to take (virtual or real) "actions" that influence the "inputs", may be.
  • Ma Ru on 17 Mar 14
     
    @Paul While I completely agree about the "embodiment done wrong" (or at least "not exactly correct") part, what you say goes exactly against one of the major claims which are connected with the notion of embodiment (google for "representational bottleneck"). The fact is your brain does *not* have resources to deal with big data. The idea therefore is that it is the body what helps to deal with what to a computer scientist appears like "big data". Understanding how this happens is key. Whether it is the problem of scale or of actually understanding what happens should be quite conclusively shown by the outcomes of the Blue Brain project.
  • johannessimon81 on 17 Mar 14
     
    Wouldn't one expect that to produce consciousness (even in a lower form) an approach resembling that of nature would be essential? All animals grow from a very simple initial state (just a few cells) and have only a very limited number of sensors AND processing units. This would allow for a fairly simple way to create simple neural networks and to start up stable neural excitation patterns. Over time as complexity of the body (sensors, processors, actuators) increases the system should be able to adapt in a continuous manner and increase its degree of self-awareness and consciousness. On the other hand, building a simulated brain that resembles (parts of) the human one in its final state seems to me like taking a person who is just dead and trying to restart the brain by means of electric shocks.
  • Paul N on 17 Mar 14
     
    Actually on a neuronal level all information gets processed. Not all of it makes it into "conscious" processing or attention. Whatever makes it into conscious processing is a highly reduced representation of the data you get. However that doesn't get lost. Basic, low processed data forms the basis of proprioception and reflexes. Every step you take is a macro command your brain issues to the intricate sensory-motor system that puts your legs in motion by actuating every muscle and correcting every step deviation from its desired trajectory using the complicated system of nerve endings and motor commands. Reflexes which were build over the years, as those massive amounts of data slowly get integrated into the nervous system and the the incipient parts of the brain. But without all those sensors scattered throughout the body, all the little inputs in massive amounts that slowly get filtered through, you would not be able to experience your body, and experience the world. Every concept that you conjure up from your mind is a sort of loose association of your sensorimotor input. How can a robot understand the concept of a strawberry if all it can perceive of it is its shape and color and maybe the sound that it makes as it gets squished? How can you understand the "abstract" notion of strawberry without the incredibly sensible tactile feel, without the act of ripping off the stem, without the motor action of taking it to our mouths, without its texture and taste? When we as humans summon the strawberry thought, all of these concepts and ideas converge (distributed throughout the neurons in our minds) to form this abstract concept formed out of all of these many many correlations. A robot with no touch, no taste, no delicate articulate motions, no "serious" way to interact with and perceive its environment, no massive flow of information from which to chose and and reduce, will never attain human level intelligence. That's point 1. Point 2 is that mere pattern recogn
  • Ma Ru on 18 Mar 14
     
    All information *that gets processed* gets processed but now we arrived at a tautology. The whole problem is ultimately nobody knows what gets processed (not to mention how). In fact an absolute statement "all information" gets processed is very easy to dismiss because the characteristics of our sensors are such that a lot of information is filtered out already at the input level (e.g. eyes). I'm not saying it's not a valid and even interesting assumption, but it's still just an assumption and the next step is to explore scientifically where it leads you. And until you show its superiority experimentally it's as good as all other alternative assumptions you can make. I only wanted to point out is that "more processing" is not exactly compatible with some of the fundamental assumptions of the embodiment. I recommend Wilson, 2002 as a crash course.
  • Paul N on 24 Mar 14
     
    These deal with different things in human intelligence. One is the depth of the intelligence (how much of the bigger picture can you see, how abstract can you form concept and ideas), another is the breadth of the intelligence (how well can you actually generalize, how encompassing those concepts are and what is the level of detail in which you perceive all the information you have) and another is the relevance of the information (this is where the embodiment comes in. What you do is to a purpose, tied into the environment and ultimately linked to survival). As far as I see it, these form the pillars of human intelligence, and of the intelligence of biological beings. They are quite contradictory to each other mainly due to physical constraints (such as for example energy usage, and training time). "More processing" is not exactly compatible with some aspects of embodiment, but it is important for human level intelligence. Embodiment is necessary for establishing an environmental context of actions, a constraint space if you will, failure of human minds (i.e. schizophrenia) is ultimately a failure of perceived embodiment. What we do know is that we perform a lot of compression and a lot of integration on a lot of data in an environmental coupling. Imo, take any of these parts out, and you cannot attain human+ intelligence. Vary the quantities and you'll obtain different manifestations of intelligence, from cockroach to cat to google to random quake bot. Increase them all beyond human levels and you're on your way towards the singularity.
LeopoldS

Times Higher Education - Top nations in physics - 5 views

www.timeshighereducation.co.uk/story.asp

statistics physics PHY

shared by LeopoldS on 18 Feb 10 - Cached
  • LeopoldS on 18 Feb 10
     
    another stat on publication comparisons - this time physics
  • Nicholas Lan on 26 Feb 10
     
    see, it's not just football where Scotland compete separately from england
ESA ACT

Nature article on economics and physics - 0 views

www.nature.com/...4551181a.pdf

economy modelling INF physics economics

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    nice nature article on the need for economics to use more physics in their approach to model markets - LS
ESA ACT

FQXi: Foundational Questions in Physics & Cosmology - 0 views

www.fqxi.org

science Research physics astronomy cosmology PHY

shared by ESA ACT on 24 Apr 09 - Cached
  • ESA ACT on 24 Apr 09
     
    To catalyze, support, and disseminate research on questions at the foundations of physics and cosmology, particularly new frontiers and innovative ideas integral to a deep understanding of reality but unlikely to be supported by conventional funding sourc
Thijs Versloot

A Groundbreaking Idea About Why Life Exists - 1 views

www.businessinsider.com/g-idea-of-lifes-origin-2014-12

life physics mathematics

shared by Thijs Versloot on 15 Dec 14 - No Cached
  • Thijs Versloot on 15 Dec 14
     
    Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. The formula, based on established physics, indicates that when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy. This could mean that under certain conditions, matter inexorably acquires the key physical attribute associated with life. The simulation results made me think of Jojo's attempts to make a self-assembling space structure. Seems he may have been on the right track, just not thinking big enough
  • johannessimon81 on 15 Dec 14
     
    :-P Thanks Thijs... I do not agree with the premise of the article that a possible correlation of energy dissipation in living systems and their fitness means that one is the cause for the other - it may just be that both go hand-in-hand because of the nature of the world that we live in. Maybe there is such a drive for pre-biotic systems (like crystals and amino acids), but once life as we know it exists (i.e., heredity + mutation) it is hard to see the need for an amendment of Darwin's principles. The following just misses the essence of Darwin: "If England's approach stands up to more testing, it could further liberate biologists from seeking a Darwinian explanation for every adaptation and allow them to think more generally in terms of dissipation-driven organization. They might find, for example, that "the reason that an organism shows characteristic X rather than Y may not be because X is more fit than Y, but because physical constraints make it easier for X to evolve than for Y to evolve." Darwin's principle in its simplest expression just says that if a genome is more effective at reproducing it is more likely to dominate the next generation. The beauty of it is that there is NO need for a steering mechanism (like maximize energy dissipation) any random set of mutations will still lead to an increase of reproductive effectiveness. BTW: what does "better at dissipating energy" even mean? If I run around all the time I will have more babies? Most species that prove to be very successful end up being very good at conserving energy: trees, turtles, worms. Even complexity of an organism is not a recipe for evolutionary success: jellyfish have been successful for hundreds of millions of years while polar bears are seem to be on the way out.
LeopoldS

physicists explain what AI researchers are actually doing - 5 views

arxiv.org/1410.3831

AI PHY

shared by LeopoldS on 07 Dec 14 - No Cached
  • LeopoldS on 07 Dec 14
     
    love this one ... it seems to take physicist to explain to the AI crowd what they are actually doing ... Deep learning is a broad set of techniques that uses multiple layers of representation to automatically learn relevant features directly from structured data. Recently, such techniques have yielded record-breaking results on a diverse set of difficult machine learning tasks in computer vision, speech recognition, and natural language processing. Despite the enormous success of deep learning, relatively little is understood theoretically about why these techniques are so successful at feature learning and compression. Here, we show that deep learning is intimately related to one of the most important and successful techniques in theoretical physics, the renormalization group (RG). RG is an iterative coarse-graining scheme that allows for the extraction of relevant features (i.e. operators) as a physical system is examined at different length scales. We construct an exact mapping from the variational renormalization group, first introduced by Kadanoff, and deep learning architectures based on Restricted Boltzmann Machines (RBMs). We illustrate these ideas using the nearest-neighbor Ising Model in one and two-dimensions. Our results suggests that deep learning algorithms may be employing a generalized RG-like scheme to learn relevant features from data.
jcunha

The physics of life - 2 views

www.nature.com/...the-physics-of-life-1.19105

science BIO PHY

shared by jcunha on 07 Jan 16 - No Cached
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  • jcunha on 07 Jan 16
     
    Research in active-matter systems is a growing field in biology. It consists in using theoretical statistical physics in living systems such as molecule colonies to deduce macroscopic properties. The aim and hope is to understand how cells divide, take shape and move on these systems. Being a crossing field between physics and biology "The pot of gold is at the interface but you have to push both fields to their limits." one can read
  • LeopoldS on 17 Jan 16
     
    Maybe we should discuss about this active matter one of these days? "These are the hallmarks of systems that physicists call active matter, which have become a major subject of research in the past few years. Examples abound in the natural world - among them the leaderless but coherent flocking of birds and the flowing, structure-forming cytoskeletons of cells. They are increasingly being made in the laboratory: investigators have synthesized active matter using both biological building blocks such as microtubules, and synthetic components including micrometre-scale, light-sensitive plastic 'swimmers' that form structures when someone turns on a lamp. Production of peer-reviewed papers with 'active matter' in the title or abstract has increased from less than 10 per year a decade ago to almost 70 last year, and several international workshops have been held on the topic in the past year."
LeopoldS

Internet billionaire ponies up more cash for physics prizes : Nature News Blog - 1 views

blogs.nature.com/...e-cash-for-physics-prizes.html

prize physics PHY

shared by LeopoldS on 09 Oct 12 - No Cached
  • LeopoldS on 09 Oct 12
     
    good news for the theoretical physicists ...
Alexander Wittig

Has a Hungarian physics lab found a fifth force of nature? - 1 views

www.nature.com/...-fifth-force-of-nature-1.19957

science

shared by Alexander Wittig on 17 Aug 16 - No Cached
  • Alexander Wittig on 17 Aug 16
     
    MTA-Atomki A laboratory experiment in Hungary has spotted an anomaly in radioactive decay that could be the signature of a previously unknown fifth fundamental force of nature, physicists say - if the finding holds up. Would be cool, after all the high energy physics being done to verify the SM it could be extended at the other end where nobody bothered to look ;)
santecarloni

Special Relativity And The Curious Physics of Chronology - Technology Review - 0 views

www.technologyreview.com/...ity-and-the-curious-physics-of

relativity physics

shared by santecarloni on 22 Aug 12 - No Cached
  • santecarloni on 22 Aug 12
     
    Einstein showed that two unrelated events can appear in any order depending on your point of view. Now physicists have discovered the chronologies of three events, and more
santecarloni

The Counterintuitive Physics of Tarzan Swings - Technology Review - 1 views

www.technologyreview.com/...itive-physics-of-tarzan-swings

physics Phy

shared by santecarloni on 03 Sep 12 - No Cached
  • santecarloni on 03 Sep 12
     
    ...
santecarloni

Physics of writing is derived at last - physicsworld.com - 0 views

physicsworld.com/...47933

writing phy technology

shared by santecarloni on 29 Nov 11 - No Cached
  • santecarloni on 29 Nov 11
     
    While humans have been writing for at least 5000 years, we have surprisingly little understanding of the physics underlying how ink moves from pen to paper. Now, physicists in South Korea and the US have worked out a theory - backed by experiment - that suggests the ink's flow rate depends on a tug-of-war that is played out between the capillary properties of pen and paper.
santecarloni

More evidence found for quantum physics in photosynthesis - 3 views

arstechnica.com/...-physics-in-photosynthesis.ars

quantum physics photosynthesis BIO science

shared by santecarloni on 08 Dec 11 - No Cached
  • LeopoldS on 11 Dec 11
     
    see papers I have just sent you this afternoon ...
Thijs Versloot

Does your iPhone have free will? #arXiv - 3 views

medium.com/...1e223b77e60

technology behavior

shared by Thijs Versloot on 22 Oct 13 - No Cached
  • Thijs Versloot on 22 Oct 13
     
    If you've ever found your iPhone taking control of your life, there may be a good reason. It may think it has free will. That may not be quite as far-fetched as it sounds. Today, one leading scientist outlines a 'Turing Test' for free will and says that while simple devices such as thermostats cannot pass, more complex ones like iPhones might.
  • ...3 more comments...
  • Luzi Bergamin on 22 Oct 13
     
    An interesting paper about how you should *NOT* think about free will...
  • johannessimon81 on 23 Oct 13
     
    I must say that the fact that the outcome of a thought process is not evident to myself in advance sounds like a more plausible explanation than 'free will' being the product of quantum mechanics. The later would not only produce unpredictable decisions but probably also irrational ones...
  • Paul N on 24 Oct 13
     
    Even if it were the product of quantum mechanics, it's still the result of external interference and not the result of 'free' will. It doesn't matter if the external input is deterministic or random, it's still external and it's not "YOU" that decided stuff.
  • Luzi Bergamin on 24 Oct 13
     
    I don't know the inventor of that nonsense that the free will should be the result of QM. It's about the only point I agree with the author of the paper: QM is not necessary and doesn't help. What I meant: all these thought experiments done by typical ultra-naive realists (or ultra-naive physicalists, if you prefer) that cultivate the university departments of physics, computer science etc. are put the cart before the horse. First one has to clarify the role of physical theories and its concepts (e.g. causality) and then one can start to ask how "free will" could perhaps be seen in these theories. More than 200 years ago there existed a famous philosopher named Kant who had some interesting thoughts about this. But authors like Lloyd behave as if he never existed, in fact is view of the world is even pre-Platonic!
  • LeopoldS on 27 Oct 13
     
    Henry Kissinger How I'm missing yer And wishing you were here
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