Skip to main content

Home/ Advanced Concepts Team/ Group items tagged physics

Rss Feed Group items tagged

jcunha

Pathological Science - 0 views

  •  
    More in the ethic realm, I once was in a talk by Ivan Schuller (http://ischuller.ucsd.edu/) where he revisited the concept of Langmuir's Pathological Science (http://yclept.ucdavis.edu/course/280/Langmuir.pdf), defined as the act in which "people are tricked into false results ... by subjective effects, wishful thinking or threshold interactions" providing a list of aspects common to fraudulent science.

    Unfortunately there is no video of this very interesting talk, but the slides are available here: http://ethics.ucsd.edu/seminars/seminars/2006/summaries/Pathological_Science.pdf
Thijs Versloot

A Groundbreaking Idea About Why Life Exists - 1 views

  •  
    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
  •  
    :-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.
Thijs Versloot

Light bending material facilitates the search for new particles - 0 views

  •  
    The problem is that the light cone angle has a limit - all particles with high momentum (mass x velocity) generate light cones with the same angle. Hence, these particles are indistinguishable. Now Chalmers researcher Philippe Tassin and his colleagues at the Free University of Brussels have designed a material that manipulates the Cherenkov cone so that also particles with high momentum get a distinct light cone angle too. The work is on the cover of this week's issue of the journal Physical Review Letters ("Controlling Cherenkov Radiation with Transformation-Optical Metamaterials").
Thijs Versloot

The Reality of Quantum Mechanics @WIRED - 3 views

  •  
    "Quantum mechanics is very successful; nobody's claiming that it's wrong," said Paul Milewski, a professor of mathematics at the University of Bath in England who has devised computer models of bouncing-droplet dynamics. "What we believe is that there may be, in fact, some more fundamental reason why [quantum mechanics] looks the way it does."
Tom Gheysens

Electron 'antenna' tunes in to physics beyond Higgs - 0 views

  •  
    Anna, Sante, some Christmas reading!

    Real theoretical physicists never sleep ;)

LeopoldS

Peter Higgs: I wouldn't be productive enough for today's academic system | Science | Th... - 1 views

  •  
    what an interesting personality ... very symathetic

    Peter Higgs, the British physicist who gave his name to the Higgs boson, believes no university would employ him in today's academic system because he would not be considered "productive" enough.

    The emeritus professor at Edinburgh University, who says he has never sent an email, browsed the internet or even made a mobile phone call, published fewer than 10 papers after his groundbreaking work, which identified the mechanism by which subatomic material acquires mass, was published in 1964.

    He doubts a similar breakthrough could be achieved in today's academic culture, because of the expectations on academics to collaborate and keep churning out papers. He said: "It's difficult to imagine how I would ever have enough peace and quiet in the present sort of climate to do what I did in 1964."

    Speaking to the Guardian en route to Stockholm to receive the 2013 Nobel prize for science, Higgs, 84, said he would almost certainly have been sacked had he not been nominated for the Nobel in 1980.

    Edinburgh University's authorities then took the view, he later learned, that he "might get a Nobel prize - and if he doesn't we can always get rid of him".

    Higgs said he became "an embarrassment to the department when they did research assessment exercises". A message would go around the department saying: "Please give a list of your recent publications." Higgs said: "I would send back a statement: 'None.' "

    By the time he retired in 1996, he was uncomfortable with the new academic culture. "After I retired it was quite a long time before I went back to my department. I thought I was well out of it. It wasn't my way of doing things any more. Today I wouldn't get an academic job. It's as simple as that. I don't think I would be regarded as productive enough."

    Higgs revealed that his career had also been jeopardised by his disagreements in the 1960s and 7
  •  
  •  
    interesting one - Luzi will like it :-)
Thijs Versloot

Black Hole Analogue Discovered in South Atlantic Ocean - 0 views

  •  
    Vortices in the South Atlantic are mathematically equivalent to black holes, say physicists, an idea that could lead to new ways of understanding how currents transport oil and garbage across oceans Black holes are regions of spacetime in which gravity is strong enough to prevent anything escaping, even light.
LeopoldS

Does the Feigel effect violate the first law? - 2 views

  •  
    interestingly also with a reference to the ariadna study of Andreas ...
Isabelle Dicaire

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

  •  
    New Earth climate model based on statistical physics and available on the App Store !
  •  
    not overly intuitive ...
LeopoldS

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

  •  
    good news for the theoretical physicists ...
santecarloni

BBC News - Atomic bond types discernible in single-molecule images - 0 views

  •  
    A pioneering team from IBM in Zurich has published single-molecule images so detailed that the type of atomic bonds between their atoms can be discerned.
santecarloni

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

  •  
    ...
santecarloni

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

  •  
    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
LeopoldS

FPP - 4 views

  •  
    Seems as if the guy likes string theory ... Luzi won't be happy :-)
  •  
    No comment!
LeopoldS

Nature article on "walking on liquids" ... as Johannes has shown us - 5 views

  •  
    nice article - with related podcast interviewing the former prof of Johannes ... my usual question: can we use it for space :-)
  •  
    Eventually for damping purposes. Place a payload in it, surrounded by the fluid, and high frequency shocks might be damped. Of course, damping properties might turn out to be not good.
santecarloni

Relativistic Baseball - 2 views

  •  
    What would happen if you tried to hit a baseball pitched at 90% the speed of light?

    --not sure it is correct, but it would be a lot of fun :)
LeopoldS

[1202.4993] Gate-tuning of graphene plasmons revealed by infrared nano-imaging - 0 views

  •  
    Basis for after next generation processors?
santecarloni

Antimatter Propulsion Engine Redesigned Using CERN's Particle Physics Simulat... - 1 views

  •  
    Latest simulation shows that the magnetic nozzles required for antimatter propulsion could be vastly more efficient than previously thought--and built with today's technologies
1 - 20 of 50 Next › Last »
Showing 20 items per page