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Gareth Jones

Looking in the Wrong Places | Edge.org - 5 views

www.edge.org/...er-looking-in-the-wrong-places

NaturalScience senseperception paradigm

shared by Gareth Jones on 19 May 18 - No Cached
  • We should be very careful in thinking about whether we’re working on the right problems. If we don’t, that ties into the problem that we don’t have experimental evidence that could move us forward. We're trying to develop theories that we use to find out which are good experiments to make, and these are the experiments that we build.   We build particle detectors and try to find dark matter; we build larger colliders in the hope of producing new particles; we shoot satellites into orbit and try to look back into the early universe, and we do that because we hope there’s something new to find there. We think there is because we have some idea from the theories that we’ve been working on that this would be something good to probe. If we are working with the wrong theories, we are making the wrong extrapolations, we have the wrong expectations, we make the wrong experiments, and then we don’t get any new data. We have no guidance to develop these theories. So, it’s a chicken and egg problem. We have to break the cycle. I don’t have a miracle cure to these problems. These are hard problems. It’s not clear what a good theory is to develop. I’m not any wiser than all the other 20,000 people in the field.
  • I’m still asking myself the same question that I asked myself ten years ago: "What is going on in my community?" I work in the foundations of physics, and I see a lot of strange things happening there. When I look at the papers that are being published, many of them seem to be produced simply because papers have to be produced. They don’t move us forward in any significant way. I get the impression that people are working on them not so much because it’s what they’re interested in but because they have to produce outcomes in a short amount of time. They sit on short-term positions and have short-term contracts, and papers must be produced.
  • The field that I mostly work in is the foundations of physics, which is, roughly speaking, composed of cosmology, the foundations of quantum mechanics, high-energy particle physics, and quantum gravity. It’s a peculiar field because there hasn’t been new data for almost four decades, since we established the Standard Model of particle physics. There has been, of course, the Higgs particle that was discovered at the LHC in 2012, and there have been some additions to the Standard Model, but there has not been a great new paradigm change, as Kuhn would have put it. We’re still using the same techniques, and we’re still working with the same theories as we did in the 1970s.
  • ...10 more annotations...
  • That makes this field of science rather peculiar and probably explains why there hasn’t been much progress. But it’s not like we don’t have any questions that need to be answered. There are a lot of questions that have been around for decades. For example, what is dark energy? What is dark matter? What are the masses of the Standard Model particles? And what’s up with the foundation of quantum mechanics? Is a theory that's fundamentally not deterministic, where we cannot predict outcomes, the last word that we have, or is there something more to it? Is there maybe another underlying structure to reality?
  • but we haven't reached the fundamental level. Maybe we will never reach it. Certainly, the theories that we have right now are not all there is. The question is, of course, if we don’t have any guidance by experiment, how do we make progress? And are we doing the right thing?
  • We’ve reached this point where we have to carefully rethink if the criteria that we’re using to select our theories are promising at all. If one looks at the history of this field in the foundations of physics, progress has usually been made by looking at questions that, at least in hindsight, were well posed, where there was an actual mathematical contradiction. For example, special relativity is incompatible with Newtonian gravity. If you try to resolve this incompatibility, you get general relativity.
  • There are various similar examples where such breakthroughs have happened because there was a real problem. There was an inconsistency and people had to resolve it. It had nothing to do with beauty. Maybe beauty was, in some cases, the personal motivation of the people to work on it. There’s certainly some truth to this, but I don’t think it’s good to turn this story around and say that if we only pay attention to this motivation that comes from ideals of beauty it will lead to progress.
  • If we are working with the wrong theories, we are making the wrong extrapolations, we have the wrong expectations, we make the wrong experiments, and then we don’t get any new data. We have no guidance to develop these theories. So, it’s a chicken and egg problem. We have to break the cycle. I don’t have a miracle cure to these problems. These are hard problems. It’s not clear what a good theory is to develop. I’m not any wiser than all the other 20,000 people in the field.
  • The way that research is funded in foundations of physics and in many other fields just puts a lot of things at a disadvantage that are not pursued anymore. Typically, everything that takes longer than three years to complete, no one will start it because they can’t afford it. They can literally not afford it.
  • Who makes the decisions about the funding? Superficially, people say that it's a funding agency, so it’s the university who get to hire people. But that puts the blame on the wrong party. In the end it’s the community itself who makes the decisions. What do the funding agencies do if they get a proposal? They send it to reviewers. And who are the reviewers? They're people from the same community. If you look at how hiring decisions are being made, there’s some committee and they are people from the same community. They have some advisory boards or something, which contains people from the same community.
  • Even if that wasn’t so, what the people in these committees would be doing is looking at easy measures for scientific success. Presently, the most popular of these measures are the number of publications and the number of citations. And maybe also whether the person has published in high-impact journals. So, these are the typical measures that are presently being used. But what do they measure? They primarily measure popularity. They indicate whether somebody’s research is well received by a lot of people in the same community. And that’s why once a research area grows beyond a certain critical mass, you have sufficiently many people who tell each other that what they’re doing is the good thing to do. They review each other’s papers and say that that’s great and it's what we should continue to do. It’s a problem in all communities that grow beyond a certain size.
  • I later came to the United States and then Canada, and that gave me the opportunity to learn a lot about quantum gravity. I also figured out that much of what goes on in quantum gravity is very detached from reality. It’s pretty much only mathematics. Yes, the mathematics is there, but I still don’t know if it’s the mathematics that describes reality.
  • That’s the very reason why we don’t normally think of gravity as a weak force. It’s the only force that is left over on long distances, and the reason for this is that it adds up. It gets stronger the more mass you pile up. More precisely, we should say that the reason we find it so hard to measure quantum gravitational effects is that we either have a particle that has very pronounced quantum properties, like, say, a single electron or something like that, but then it’s so light that we cannot measure the gravitational field. Or we have some object that is so heavy that we can measure the gravitational field, but then it doesn’t have quantum properties. Okay, so that’s the actual problem.
ZeroDivide .

Nova Fabric of the cosmos The illusion of time full video - YouTube - 48 views

www.youtube.com/watch

Time

shared by ZeroDivide . on 03 Aug 14 - No Cached
  • The Evolution of Time and the Carnot Cycle at the Edge of the Universe
  • ZeroDivide . on 03 Aug 14
     
    We are all time travelers... drifting through time at a steady pace, one moment at a time. In what direction are we moving through time? Or does time move through us? How many dimensions of time are there? Though slightly allegorical, three-dimensional time offers physics new parameters, accounting for conventional and exotic physical phenomena, while maintaining the conservation of energy and symmetry groups found in physical law.  I began playing with the idea that all of physics could be reduced to just interactions between spatial and temporal coordinates. I wondered if inertia and momentum might be composed strictly of temporal components. This would require extra time dimensions. Could inertia or momentum be used as indicators of multi-dimensional time? What about charge, spin, and other properties of matter? Answers to some of these questions appeared to reside in neutrino research, specifically neutrino flavor oscillation.  The universality between Thermodynamics and Temporal Mechanics can reduce the fundamental forces of nature into a single expression, a new equivalence principle, which can be used as the generator for the evolution of time. Once Quantum Mechanics is seen through the lens of three-dimensional time, the EPR paradox looses its mystique. The speed of light may be restricted to a set speed limit within each individual frame of reference, however, frames of reference can undergo periods-of-time at varying rates of the passage-of-time. If the positive side of absolute zero is a state of condensed matter, what is on the negative side of absolute zero? Uncondensed matter?  The anti-matter aspect of the Dirac equations may have been misinterpreted. The convention is to assume that "matter" is composed of "particles" distinctly different from "antimatter" composed of "antiparticles". The assumption of one time dimension locks in this interpretation of the Dirac Equations. However, the uniform production of particles and antipa
Jac Londe

Truly random numbers - 41 views

www.zmescience.com/...generated-with-quantum-physics

numbers quantum physics science onde

shared by Jac Londe on 29 Nov 11 - No Cached
  • At a quantum scale, the motion of electrons and protons is completely and genuinely random, since it doesn’t follow a clear path of cause and effect. You basically have no idea what’s going to happen. If you can measure this somehow, than you’ve got yourself an absolutely random value.
  • “If you want to defeat an adversary who is trying to hack into your system, basically you need large quantities of random numbers,”  Sussman said.
  • “…a truly random number generator will provide impenetrable encryption for communications — be they military transmissions, secure banking, or online purchasing — that underpin the modern connected world.”
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  • The researchers used pulses of laser light, which only last a trillionth of a second, that were directed through a diamond. The light comes and goes through the diamond, however when it exists it’s changed, since it has to pass through quantum vacuum fluctuations, the microscopic flickering of the amount of energy in a point in space. Scientists can measure these pulses of light that emerge from the experimental set-up, measurements which are the truly random.
  • random numbers
  • with quantum physics
Jac Londe

Scientists make quantum breakthrough - 25 views

www.physorg.com/...ists-quantum-breakthrough.html

science news physics technology research tech education quantum scientists

shared by Jac Londe on 25 Apr 11 - No Cached
  • Scientists have demonstrated for the first time that atoms can be guided in a laser beam and possess the same properties as light guided in an optical communications fiber.
  • Abstract Speckle patterns produced by multiple independent light sources are a manifestation of the coherence of the light field. Second-order correlations exhibited in phenomena such as photon bunching, termed the Hanbury Brown–Twiss effect, are a measure of quantum coherence. Here we observe for the first time atomic speckle produced by atoms transmitted through an optical waveguide, and link this to second-order correlations of the atomic arrival times. We show that multimode matter-wave guiding, which is directly analogous to multimode light guiding in optical fibres, produces a speckled transverse intensity pattern and atom bunching, whereas single-mode guiding of atoms that are output-coupled from a Bose–Einstein condensate yields a smooth intensity profile and a second-order correlation value of unity. Both first- and second-order coherence are important for applications requiring a fully coherent atomic source, such as squeezed-atom interferometry.
  • Australian National University
Marita Thomson

Quantum Victoria | A Centre of Excellence & Innovation in Science & Mathematics - 78 views

www.quantumvictoria.vic.edu.au

innovation teaching training science maths PD

shared by Marita Thomson on 11 May 11 - No Cached
  • Marita Thomson on 11 May 11
     
    Quantum Victoria will deliver an online professional development module that will equip teachers with the skills and tools necessary for teaching in 21st century learning environments. This embedded professional development opportunity will focus primarily on project-based learning (PBL) and the effective integration of ICT in the areas of science, technology, engineering and mathematics. ... [more]
Gerald Carey

Quantum Levitation - YouTube - 69 views

www.youtube.com/watch

quantum levitation science youtube physics

shared by Gerald Carey on 11 Nov 11 - No Cached
  • Gerald Carey on 11 Nov 11
     
    An amazing video even if you are not a Physicist. 
Tony Baldasaro

americas-best-high-schools-2010: Personal Finance News from Yahoo! Finance - 32 views

finance.yahoo.com/...mericas-best-high-schools-2010

highschool top rigor

shared by Tony Baldasaro on 10 Dec 09 - Cached
  • What are the social responsibilities of educated people? Over the course of the school year, students are exploring social responsibility through projects of their own design, ranging from getting school supplies for students with cerebral palsy in Shanghai to persuading their classmates to use handkerchiefs to reduce paper waste.
  • Tony Baldasaro on 10 Dec 09
     
    Thomas Jefferson High School for Science and Technology in Alexandria, Va., the top school in U.S. News & World Report's America's Best High Schools rankings, is designed to challenge students. A course load of offerings that include DNA science, neurology, and quantum physics would seem to be more than enough to meet that goal. But students and the faculty felt those classes weren't enough, so they decided to tackle another big question: What are the social responsibilities of educated people? Over the course of the school year, students are exploring social responsibility through projects of their own design, ranging from getting school supplies for students with cerebral palsy in Shanghai to persuading their classmates to use handkerchiefs to reduce paper waste. The One Question project demonstrates the way "TJ," as it's referred to by students and teachers, encourages the wide-ranging interests of its students.
Michele Brown

HowStuffWorks - Learn How Everything Works! - 30 views

www.howstuffworks.com

reference science kids howto education technology information learning

shared by Michele Brown on 02 Feb 10 - Cached
  • Michele Brown on 29 Jan 11
     
    Cool site that provides information on everything from "how dogs perceive time" to Quantum Mechanics.
  • Gerald Carey on 05 Feb 11
     
    Take the site with a grain of salt. It's not very critical of what you might term "pseudo-science" e.g. homeopathy.
Nanette Blank

Global Warming for Non-science Majors - 13 views

www.youtube.com/view_play_list

Science video teaching

shared by Nanette Blank on 21 Apr 10 - Cached
  • Nanette Blank on 21 Apr 10
     
    This 10-week course for non-science majors focuses on a single problem: assessing the risk of human-caused climate change. The story ranges from physics to chemistry, biology, geology, fluid mechanics, and quantum mechanics, to economics and social sciences. The class will consider evidence from the distant past and projections into the distant future, keeping the human time scale of the next several centuries as the bottom line. The lectures follow a textbook, "Global Warming, Understanding the Forecast," written for the course. For information about the textbook, interactive models, and more, visit: http://forecast.uchicago.edu/
jhave2

"Completely implausible"-a controversial paper exists, but so do black holes | Ars Tech... - 11 views

arstechnica.com/...r-exists-but-so-do-black-holes

astrophysics black holes

shared by jhave2 on 03 Mar 15 - No Cached
  • If correct, this applies everywhere
    • jhave2
      jhave2 on 03 Mar 15
       
      incorrect.
    • jhave2
      jhave2 on 03 Mar 15
       
      nothing applies everywhere.
  • jhave2 on 03 Mar 15
     
    "In order to conclude that black holes don't exist, she claims to have united general relativity with quantum mechanics"
Josephine Dorado

Time Travelers Ep 5 - Quantum Entangled - YouTube - 24 views

www.youtube.com/watch

machinima education science energy sustainability health

shared by Josephine Dorado on 29 Jul 12 - No Cached
  • Josephine Dorado on 29 Jul 12
     
    The award winning series, Time Travelers, is an animated adventure series about the future. The series showcases future careers in science such as geoengineering for alternative energy, nanobiolology and neuroscience for learning and health care.
Bruce Gurnick

The Scale of the Universe 2 - 87 views

htwins.net/scale2

tools resources

shared by Bruce Gurnick on 15 Feb 12 - No Cached
  • Martin Burrett on 15 Feb 12
     
    An amazing sequel to Scale of the Universe. See the smallest and biggest objects in our universe. This version is animated and has lots more objects to view. http://ictmagic.wikispaces.com/Science
  • ...1 more comment...
  • anonymous on 18 Feb 12
     
    Powers of 10 for the web browser!
  • Bob Rowan on 01 Mar 12
     
    compares the size of small and large objects that make up our known universe; shared by Ginny Byrne
  • Bruce Gurnick on 02 Mar 12
     
    Zoom from the edge of the universe to the quantum foam of spacetime and learn about everything in between.
carmelladoty

Albert Einstein - The Quantum Theory - Documentary 2014 - YouTube - 31 views

www.youtube.com/watch

DENSI2015 Vertasium Learning

shared by carmelladoty on 16 Jul 15 - No Cached
  • carmelladoty on 16 Jul 15
     
    Good video - How do students learn through different media? What experience promote learning? It has been shown that words and pictures are used together are better. is YoutTube the answer? The video brings up some really good points.
Jac Londe

Scientists capture first direct images of theoretically predicted magnetic monopoles - 19 views

www.physorg.com/...es-theoretically-magnetic.html

images capture scientists science onde

shared by Jac Londe on 25 Oct 10 - No Cached
  • first direct images of
  • magnetic monopoles
  • Image representing 12 micrometer x 12 micrometer of artificial magnetic metamaterial where monopoles can be seen at each end of the Dirac strings, visible as dark lines. The dark regions correspond to magnetic islands where the magnetization is reversed. (Image courtesy of Paul Scherrer Institute)
  • ...3 more annotations...
  • “A magnetic monopole is a ‘hypothetical’ particle that is a magnet with only one single magnetic pole,” says UCD Theoretical Physicist, Professor Hans-Benjamin Braun from the UCD School of Physics, who co-led the study with Dr Laura Heyderman from the Paul Scherrer Institute in Switzerland.
  • “Some of the most important theories explaining how quantum matter behaves in the universe are based on their existence, but they have eluded direct imaging since they were first theoretically conceived in the 1930s.”
  • Initially conceived by the British-Swiss theoretical physicist Dirac in 1931, monopoles were proposed to occur as emergent quasiparticles in so called pyrochlore spin-ice systems by Castelnovo, Moessner and Sondhi in 2008.
Jac Londe

Confirming Einstein, scientists find 'spacetime foam' not slowing down photons from far... - 13 views

phys.org/...scientists-spacetime-foam.html

einstein scientists quantum onde particles photons

shared by Jac Londe on 24 Mar 15 - No Cached
  • Jac Londe on 24 Mar 15
     
    One hundred years after Albert Einstein formulated the general theory of relativity, an international team has proposed another experimental proof. In a paper published today in Nature Physics, researchers from the Hebrew University of Jerusalem, the Open University of Israel, Sapienza University of ...
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