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Dario Izzo

Miguel Nicolelis Says the Brain Is Not Computable, Bashes Kurzweil's Singularity | MIT ... - 9 views

www.technologyreview.com/...the-brain-is-not-computable

Singularity AI Brain

shared by Dario Izzo on 28 Feb 13 - No Cached
LeopoldS liked it
  • Dario Izzo on 28 Feb 13
     
    As I said ten years ago and psychoanalysts 100 years ago. Luis I am so sorry :) Also ... now that the commission funded the project blue brain is a rather big hit Btw Nicolelis is a rather credited neuro-scientist
  • ...14 more comments...
  • LeopoldS on 28 Feb 13
     
    nice article; Luzi would agree as well I assume; one aspect not clear to me is the causal relationship it seems to imply between consciousness and randomness ... anybody?
  • Luís F. Simões on 01 Mar 13
     
    This is the same thing Penrose has been saying for ages (and yes, I read the book). IF the human brain proves to be the only conceivable system capable of consciousness/intelligence AND IF we'll forever be limited to the Turing machine type of computation (which is what the "Not Computable" in the article refers to) AND IF the brain indeed is not computable, THEN AI people might need to worry... Because I seriously doubt the first condition will prove to be true, same with the second one, and because I don't really care about the third (brains is not my thing).. I'm not worried.
  • Dario Izzo on 01 Mar 13
     
    In any case, all AI research is going in the wrong direction: the mainstream is not on how to go beyond Turing machines, rather how to program them well enough ...... and thats not bringing anywhere near the singularity
  • Luís F. Simões on 01 Mar 13
     
    It has not been shown that intelligence is not computable (only some people saying the human brain isn't, which is something different), so I wouldn't go so far as saying the mainstream is going in the wrong direction. But even if that indeed was the case, would it be a problem? If so, well, then someone should quickly go and tell all the people trading in financial markets that they should stop using computers... after all, they're dealing with uncomputable undecidable problems. :) (and research on how to go beyond Turing computation does exist, but how much would you want to devote your research to a non existent machine?)
  • Dario Izzo on 01 Mar 13
     
    [warning: troll] If you are happy with developing algorithms that serve the financial market ... good for you :) After all they have been proved to be useful for humankind beyond any reasonable doubt.
  • Ma Ru on 04 Mar 13
     
    Two comments from me: 1) an apparently credible scientist takes Kurzweil seriously enough to engage with him in polemics... oops 2) what worries me most, I didn't get the retail store pun at the end of article...
  • Dario Izzo on 04 Mar 13
     
    True, but after Google hired Kurzweil he is de facto being taken seriously ... so I guess Nicolelis reacted to this.
  • Ma Ru on 04 Mar 13
     
    Crazy scientist in residence... interesting marketing move, I suppose.
  • Luzi Bergamin on 05 Mar 13
     
    Unfortunately, I can't upload my two kids to the cloud to make them sleep, that's why I comment only now :-). But, of course, I MUST add my comment to this discussion. I don't really get what Nicolelis point is, the article is just too short and at a too popular level. But please realize that the question is not just "computable" vs. "non-computable". A system may be computable (we have a collection of rules called "theory" that we can put on a computer and run in a finite time) and still it need not be predictable. Since the lack of predictability pretty obviously applies to the human brain (as it does to any sufficiently complex and nonlinear system) the question whether it is computable or not becomes rather academic. Markram and his fellows may come up with a incredible simulation program of the human brain, this will be rather useless since they cannot solve the initial value problem and even if they could they will be lost in randomness after a short simulation time due to horrible non-linearities... Btw: this is not my idea, it was pointed out by Bohr more than 100 years ago...
  • Dario Izzo on 05 Mar 13
     
    I guess chaos is what you are referring to. Stuff like the Lorentz attractor. In which case I would say that the point is not to predict one particular brain (in which case you would be right): any initial conditions would be fine as far as any brain gets started :) that is the goal :)
  • Luzi Bergamin on 05 Mar 13
     
    Kurzweil talks about downloading your brain to a computer, so he has a specific brain in mind; Markram talks about identifying neural basis of mental diseases, so he has at least pretty specific situations in mind. Chaos is not the only problem, even a perfectly linear brain (which is not a biological brain) is not predictable, since one cannot determine a complete set of initial conditions of a working (viz. living) brain (after having determined about 10% the brain is dead and the data useless). But the situation is even worse: from all we know a brain will only work with a suitable interaction with its environment. So these boundary conditions one has to determine as well. This is already twice impossible. But the situation is worse again: from all we know, the way the brain interacts with its environment at a neural level depends on his history (how this brain learned). So your boundary conditions (that are impossible to determine) depend on your initial conditions (that are impossible to determine). Thus the situation is rather impossible squared than twice impossible. I'm sure Markram will simulate something, but this will rather be the famous Boltzmann brain than a biological one. Boltzman brains work with any initial conditions and any boundary conditions... and are pretty dead!
  • Dario Izzo on 05 Mar 13
     
    Say one has an accurate model of a brain. It may be the case that the initial and boundary conditions do not matter that much in order for the brain to function an exhibit macro-characteristics useful to make science. Again, if it is not one particular brain you are targeting, but the 'brain' as a general entity this would make sense if one has an accurate model (also to identify the neural basis of mental diseases). But in my opinion, the construction of such a model of the brain is impossible using a reductionist approach (that is taking the naive approach of putting together some artificial neurons and connecting them in a huge net). That is why both Kurzweil and Markram are doomed to fail.
  • johannessimon81 on 06 Mar 13
     
    I think that in principle some kind of artificial brain should be feasible. But making a brain by just throwing together a myriad of neurons is probably as promising as throwing together some copper pipes and a heap of silica and expecting it to make calculations for you. Like in the biological system, I suspect, an artificial brain would have to grow from a small tiny functional unit by adding neurons and complexity slowly and in a way that in a stable way increases the "usefulness"/fitness. Apparently our brain's usefulness has to do with interpreting inputs of our sensors to the world and steering the body making sure that those sensors, the brain and the rest of the body are still alive 10 seconds from now (thereby changing the world -> sensor inputs -> ...). So the artificial brain might need sensors and a body to affect the "world" creating a much larger feedback loop than the brain itself. One might argue that the complexity of the sensor inputs is the reason why the brain needs to be so complex in the first place. I never quite see from these "artificial brain" proposals in how far they are trying to simulate the whole system and not just the brain. Anyone? Or are they trying to simulate the human brain after it has been removed from the body? That might be somewhat easier I guess...
  • Luís F. Simões on 06 Mar 13
     
    Johannes: "I never quite see from these "artificial brain" proposals in how far they are trying to simulate the whole system and not just the brain." In Artificial Life the whole environment+bodies&brains is simulated. You have also the whole embodied cognition movement that basically advocates for just that: no true intelligence until you model the system in its entirety. And from that you then have people building robotic bodies, and getting their "brains" to learn from scratch how to control them, and through the bodies, the environment. Right now, this is obviously closer to the complexity of insect brains, than human ones. (my take on this is: yes, go ahead and build robots, if the intelligence you want to get in the end is to be displayed in interactions with the real physical world...) It's easy to dismiss Markram's Blue Brain for all their clever marketing pronouncements that they're building a human-level consciousness on a computer, but from what I read of the project, they seem to be developing a platfrom onto which any scientist can plug in their model of a detail of a detail of .... of the human brain, and get it to run together with everyone else's models of other tiny parts of the brain. This is not the same as getting the artificial brain to interact with the real world, but it's a big step in enabling scientists to study their own models on more realistic settings, in which the models' outputs get to effect many other systems, and throuh them feed back into its future inputs. So Blue Brain's biggest contribution might be in making model evaluation in neuroscience less wrong, and that doesn't seem like a bad thing. At some point the reductionist approach needs to start moving in the other direction.
  • Luzi Bergamin on 06 Mar 13
     
    @ Dario: absolutely agree, the reductionist approach is the main mistake. My point: if you take the reductionsit approach, then you will face the initial and boundary value problem. If one tries a non-reductionist approach, this problem may be much weaker. But off the record: there exists a non-reductionist theory of the brain, it's called psychology... @ Johannes: also agree, the only way the reductionist approach could eventually be successful is to actually grow the brain. Start with essentially one neuron and grow the whole complexity. But if you want to do this, bring up a kid! A brain without body might be easier? Why do you expect that a brain detached from its complete input/output system actually still works. I'm pretty sure it does not!
  • johannessimon81 on 06 Mar 13
     
    @Luzi: That was exactly my point :-)
pacome delva

Galaxy study backs general relativity - 1 views

physicsworld.com/...41948

galaxy general_relativity gravitational_lensing survey

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

Galaxy clusters back general relativity - 0 views

physicsworld.com/...47358

phy general_relativity galaxy mond teves f(r)_gravity

shared by pacome delva on 30 Sep 11 - No Cached
  • 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.
Isabelle Dicaire

Testing of a femtosecond pulse laser in outer space : Scientific Reports : Nature Publi... - 2 views

www.nature.com/...srep05134.html

shared by Isabelle Dicaire on 16 Jan 15 - No Cached
  • Isabelle Dicaire on 16 Jan 15
     
    Good news for fundamental physics and Earth system science, femtosecond lasers are now about to achieve space qualification thanks to fibre optics!  Applications include high resolution spectroscopy, absolute laser ranging, mapping of the geo-potential and testing of the theory of general relativity to name a few!
  • LeopoldS on 17 Jan 15
     
    nice paper by the Koreans, did not know that they had already such a laser in orbit for a year. How much would this type be upscalable for our needs? in case we have not, we should reference it
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.
jaihobah

A precise extragalactic test of General Relativity - 0 views

science.sciencemag.org/...1342

PHY

shared by jaihobah on 22 Jun 18 - No Cached
  • jaihobah on 22 Jun 18
     
    Einstein's theory of gravity, General Relativity (GR), has been tested precisely within the Solar System. However, it has been difficult to test GR on the scale of an individual galaxy. Collett et al. exploited a nearby gravitational lens system, in which light from a distant galaxy (the source) is bent by a foreground galaxy (the lens). Mass distribution in the lens was compared with the curvature of space-time around the lens, independently determined from the distorted image of the source. The result supports GR and eliminates some alternative theories of gravity.
Luís F. Simões

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

www.spaceref.com/...viewpr.html

nasa patents software fault-tolerance design swarm

shared by Luís F. Simões on 04 Nov 10 - No Cached
  • 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.
  • Luís F. Simões on 04 Nov 10
     
    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."
duncan barker

ESA Proves General Theory of Relativity Wrong???? - 3 views

refreshingnews9.blogspot.com/...hat-proves-general-theory.html

science space

shared by duncan barker on 12 Aug 10 - Cached
  • Luzi Bergamin on 12 Aug 10
     
    Not again, pleeeaaase!!! Alright, you don't know the story, ask Dario or Leo...
  • LeopoldS on 12 Aug 10
     
    he just did .... don't worry, it's already over again .... how are you btw?
jcunha

Wireless 10 kW power transmission - 1 views

phys.org/...n-firm-small-solar-energy.html

technology space PHY energy wireless

shared by jcunha on 17 Mar 15 - No Cached
  • jcunha on 17 Mar 15
     
    Mitsubishi Heavy Industries said Friday that it has succeeded in transmitting 10 kW of power through 500 m. An announcement that comes just after JAXA scientists reported one more breakthrough in the quest for Space Solar Power Systems (http://phys.org/news/2015-03-japan-space-scientists-wireless-energy.html). One step closer to Power Generation from Space/
  • Thijs Versloot on 17 Mar 15
     
    from the press release (https://www.mhi-global.com/news/story/1503121879.html) "10 kilowatts (kW) of power was sent from a transmitting unit by microwave. The reception of power was confirmed at a receiver unit located at a distance of 500 meters (m) away by the illumination of LED lights, using part of power transmitted". So 10kW of transmission to light a few efficient LED lights??? In a 2011 report (https://www.mhi-global.com/company/technology/review/pdf/e484/e484017.pdf), MHI estimated this would generate the same electricity output as a 400-megawatt thermal plant - or enough to serve more than 150,000 homes during peak hours. The price? The same as publicly supplied power, according to its calculations. There are no results to boost these claims however. The main work they do now is focused on beam steering control. I guess the real application in mind is more targeted to terrestrial applications, eg wireless highway charging (http://www.bbc.com/future/story/20120312-wireless-highway-to-charge-cars). With the distances so much shorter, leading to much smaller antenna's and rectenna's this makes much more sense to me to develop.
jcunha

CRISPR/Cas9 and Targeted Genome Editing: A New Era in Molecular Biology | NEB - 1 views

www.neb.com/...a-new-era-in-molecular-biology

BIO gebome editing

shared by jcunha on 25 Feb 16 - No Cached
  • jcunha on 25 Feb 16
     
    An incresingly popular scientific enome re-writting tool. Might prevent future generations from being born with some types of disorders or disabilities! Also, for fun, can be looked at one step closer to having a real wolverine..
  • jcunha on 18 Apr 16
Thijs Versloot

New Quantum Theory to explain flow of time - 2 views

www.wired.com/...quantum-theory-flow-time

energy quantum time

shared by Thijs Versloot on 26 Apr 14 - No Cached
  • Thijs Versloot on 26 Apr 14
     
    Basically quantum entanglement, or more accurately the dispersal and expansion of mixed quantum states, results in an apparent flow of time. Quantum information leaks out and the result is the move from a pure state (hot coffee) to a mixed state (cooled down) in which equilibrium is reached. Theoretically it is possible to get back to a pure state (coffee spontaneously heating up) but this statistical unlikelihood gives the appereance of irreversibility and hence a flow o time. I think an interesting question is then: how much useful work can you extract from this system? (http://arxiv.org/abs/1302.2811) It should for macroscopic thermodynamic systems lead to the Carnot cycle, but on smaller scales it might be possible to formulate a more general expression. Anybody interested to look into it? Anna, Jo? :)
  • johannessimon81 on 27 Apr 14
     
    What you propose is called Maxwell's demon: http://en.wikipedia.org/wiki/Maxwell%27s_demon Unfortunately (or maybe fortunately) thermodynamics is VERY robust. I guess if you really only want to harness AND USE the energy in a microscopic system you might have some chance of beating Carnot. But any way of transferring harvested energy to a macroscopic system seems to be limited by it (AFAIK).
Thijs Versloot

Magnetic bubble may give space probes a soft landing - 4 views

www.newscientist.com/article/mg22329763.100-magnetic-bubble-may-give-space-probes-a-soft-landing.html?cmpid=RSS|NSNS|2012-GLOBAL|physics-math#.U7aeTnWSzmE

magnetoshell aerocapture plasma entry

shared by Thijs Versloot on 04 Jul 14 - No Cached
  • Thijs Versloot on 04 Jul 14
     
    I am also looking into this idea since some time and it seems NASA is already ahead, awarding two contract to investigate magnetoshell aerocapture. This could be interesting for probes that want to enter eg Marsian atmospheres at relatively high velocity. Or for multiple re-entry s/c at Earth. The idea of the experiment, The satellite will carry a copper coil, powered by a lithium-ion battery, that generates a magnetic field around the probe. As it descends, the spacecraft will eject a small amount of plasma. This gets trapped in the magnetic field, creating a protective bubble that stops air molecules colliding with the craft and producing heat.
  • LeopoldS on 05 Jul 14
     
    A few years back Mimmo has worked on this, rather from the theory side if I remember well ...
  • Paul N on 11 Jul 14
     
    The power requirements for such a thing must be HUGE!
duncan barker

Challenging Existence of 'Absolute Time' - 3 views

www.21stcenturysciencetech.com/...time.html

phy

shared by duncan barker on 12 Aug 10 - Cached
  • Luzi Bergamin on 12 Aug 10
     
    I doubt that Shnoll is really the first one making such experiments, but perhaps they are more complete than any others done before. Similar things are very popular in the context of Psychology and more exotic fields. If I remember correctly someone ran long experiments with random number generators... Mostly the stories died after a short time, since the experiments are not reproducable. Anyway, why do these guys always have to claim that their work is somehow fundamentally changing our view of physics, notoriously referring to Einstein-Bohr debates and this stuff. That's nonsense! If these effects exist the first explanation is always much simpler. There is somewhere something that influences physics on Earth in a defined way. But this influence depends on the relative position or whatever of the Earth to that whatever-it-is. No problem with absolute time and all that sh...
  • LeopoldS on 12 Aug 10
     
    Two years ago, nearly unnoticed in the West, the Russian biophysicist S.E. Shnoll published a paper in the prominent Russian physics journal Uspekhi Fisicheskikh Nauk ..... ah then ...
  • Luzi Bergamin on 12 Aug 10
     
    You are right, Leo, they are mostly Russians that publish in some unspellable Journals nobody knows.... or then they are supported by Templeton Foundation.
Joris _

Japan probe overshoots Venus, heads toward sun - 0 views

www.washingtonpost.com/...AR2010120701077.html

MAD venus robust

shared by Joris _ on 08 Dec 10 - No Cached
sreejanag liked it
  • A Japanese probe to Venus failed to reach orbit Wednesday and was captured by the sun's gravitational pull
  • Akatsuki's engines did not fire long enough to attain the proper orbiting position
  • may be able to try again when it passes by Venus six years from now.
  • Joris _ on 08 Dec 10
     
    The usefulness of having a robust trajectory :) ... They have to wait 6 more years for another date with Venus ...
  • ...2 more comments...
  • Joris _ on 09 Dec 10
  • LeopoldS on 11 Dec 10
     
    I agree in general but just out of the stomach: is there really an optimised trajectory that would be able to avoid this kind of scenarios when main thrusters don't perform properly? Wouldn't you in any case end up in a sun-orbiting trajectory and have to come back after years??
  • Joris _ on 11 Dec 10
     
    "optimised trajectory" of course not, robust definitely! It was the subject of my paper presented at the AAS (the one in San Diego) "Designing robust interplanetary trajectories subject to one temporary engine failure". The problem here is that they do not have enough fuel for a correction maneuver that would allow to come back to Venus earlier, and break for a VOI. A robust scenario could have alloted the best amount of fuel and time to be able to recover from almost all possible unplanned events. In the paper, I introduce some confidence regions such that I get the robust control for p% chance of mission success in case m% chance of problem with the propulsion system.
  • Dario Izzo on 12 Dec 10
     
    You should run your method on this scenario and see if you could get a trajectory with a shorter come back time using the same spacecraft.... would be a big selling point for a new trajectory design approach
Luís F. Simões

Wind Power Without the Blades: Big Pics : Discovery News - 4 views

news.discovery.com/...-power-without-the-blades.html

NRG wind energy biomimicry

shared by Luís F. Simões on 19 Sep 11 - No Cached
  • The carbon-fiber stalks, reinforced with resin, are about a foot wide at the base tapering to about 2 inches at the top. Each stalk will contain alternating layers of electrodes and ceramic discs made from piezoelectric material, which generates a current when put under pressure. In the case of the stalks, the discs will compress as they sway in the wind, creating a charge.
  • Based on rough estimates, said Núñez-Ameni the output would be comparable to that of a conventional wind farm covering the same area
  • After completion, a Windstalk should be able to produce as much electricity as a single wind turbine, with the advantage that output could be increased with a denser array of stalks. Density is not possible with conventional turbines, which need to be spaced about three times the rotor's diameter in order to avoid air turbulence. But Windstalks work on chaos and turbulence so they can be installed much closer together, said Núñez-Ameni.
  • ...1 more annotation...
  • Núñez-Ameni also reports that the firm is currently working on taking the Windstalk idea underwater. Called Wavestalk, the whole system would be inverted to harness energy from the flow of ocean currents and waves.
  • Luís F. Simões on 19 Sep 11
     
    additional information: http://atelierdna.com/?p=144
  • LeopoldS on 24 Sep 11
     
    isn't this a bit of a contradiction: on the one hand: "Based on rough estimates, said Núñez-Ameni the output would be comparable to that of a conventional wind farm covering the same area" and on the other: "After completion, a Windstalk should be able to produce as much electricity as a single wind turbine, with the advantage that output could be increased with a denser array of stalks. Density is not possible with conventional turbines, which need to be spaced about three times the rotor's diameter in order to avoid air turbulence. " still, very interesting concept!
pacome delva

Physics - Nanospheres on a silver plate - 0 views

physics.aps.org/64

phy nan nanoparticle

shared by pacome delva on 05 Aug 09 - Cached
  • As a result of its high symmetry and conjugated bond structure, the electronic properties of C60 are very unusual, and there is a massive research effort toward integrating it into molecular scale electronic devices [4].
  • In this context, it is important to understand how the molecule forms bonds with a metal substrate, such as silver, which is commonly used as an electrode material.
  • The general trend in all of these cases shows that even molecules with relatively weak individual (atom-to-atom) surface bonds can induce substantial substrate reconstructions in order to create favorable adsorption sites [8]. Such “nanopatterning” of substrates is essential to the stability of ordered structures of these molecules and can critically influence their electronic structure, which is an important aspect in the design of molecular electronic devices.
Francesco Biscani

Apollo special: Mirrors on the moon - space - 12 July 2009 - New Scientist - 0 views

www.newscientist.com/...ecial-mirrors-on-the-moon.html

celestial mechanics general relativity

shared by Francesco Biscani on 12 Jul 09 - Cached
  • Francesco Biscani on 12 Jul 09
     
    Maybe Pacome can come up with some nice idea on testing GR with the reflectors on the Moon?
jmlloren

Splitting Time from Space-New Quantum Theory Topples Einstein's Spacetime - 4 views

www.scientificamerican.com/article.cfm

PHY

shared by jmlloren on 25 Nov 09 - Cached
  • jmlloren on 25 Nov 09
     
    This is the guy of Luzy's joke: "Dear, this is not what it seems. I can explain EVERYTHING!"
  • ...1 more comment...
  • Luzi Bergamin on 25 Nov 09
     
    Horava is a serious string theorist (if there is anything like that...) I like the last comment by Dvali: if the theory can be adjusted in such a way that it becomes indistinguishable from GR then it should be taken seriously. Gosh, am I glad to be among engineers now!!!
  • pacome delva on 26 Nov 09
     
    yeah an interesting theory, definitely worth following. But it is far from being mature, and a lot of work remains before saying that it is viable or not... I posted something on this some time ago (http://www.diigo.com/user/pacome/horava_theory) and proposed to do smthing on it in the idea storm (our new creative game...), which didn't have a lot of success... I like also the idea of matrix gravity (see Matrix general relativity: a new look at old problems, Ivan G Avramidi, CQG 21, 103)
  • LeopoldS on 26 Nov 09
     
    you are among what???
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