News

MiniBoone Neutrino experiment suggests fourth flavor of neutrino may exist. Also see here and here.

KEKB electron-positron collider finds evidence for a four-quark meson.

Fermi Lab has announced the discovery of a new baryon. Because it is made up of a quark from each of the 3 families of quarks, it is being called the "triple scoop".

Links

• Microsoft Station Q
• Not Even Wrong
• The AHA Foundation
• Richard Dawkins
• MacArthur Fellows 2010
• Fermi Lab

   
     While it may not be easy to do so, one can at least try to emulate Feynman's description.
      One thing I have noticed in looking at Microsoft's implementation of contravariance and covariance is that the people who write about it do not seem to have complete knowledge of the concept. To hopefully assist in remedying that situation, I will be writing a series of short articles on the concept of contravariance and covariance as it is understood in mathematics and physics, and touch on the origin of its use in programming languages.

August 5, 2009
      Feynman, Putin, and Microsoft...

     Vladimir Putin was recently shown on Russian television cavorting around Kyzyl, Tuva. (The same Tuva after which Microsoft named its  excellent Tuva Project). Tuva was made famous in the physics world in 1991 by the publication of "Tuva or Bust, Richard Feynman's Last Journey"... All this recent Tuva media attention caused me to dust off and re-read that book...leading, interestingly enough, to the discovery of a previously unknown, but unfortunately somewhat widely propagated, Feynman error.

July 27, 2009
     Charles Townes (b. 7/28/1915), inventor of the maser/laser, celebrates a birthday this week.

July 25, 2009
     Bill Gates has done a very great thing for physics education by purchasing the rights to the Feynman Messenger Series lectures and made them freely available online at the Tuva Project.  Thank you, Mr. Gates!

May 31, 2009
         The superior accomplishment of Jewish physicists has always presented a puzzle.

Feynman touched on an explanation in his "Is Electricity Fire" Feynman story:

     "One of the questions the rabbinical students and I discussed at some length was why it is that in academic things, such as theoretical physics, there is a higher proportion of Jewish kids than their proportion in the general population. The rabbinical students thought the reason was that the Jews have a history of respecting learning: They respect their rabbis, who are really teachers, and they respect education. The Jews pass on this tradition in their families all the time, so that if a boy is a good student, it's as good as, if not better than, being a good football player."

Eugene Wigner attributed the success of Jewish immigrants in physics to hard work:

      "Many people have asked me: 'Why was this generation of Jewish Hungarians so brilliant?' Let me begin by making clear it was not a matter of genetic superiority. Let us leave such ideas to Adolf Hitler. How could anyone feel 'genetically superior' to Enrico Fermi or Werner Heisenberg? Much of the credit belongs to the superb high schools in Budapest, which gave us a wonderful start. But a greater spur to our success was probably the fact of our forced emigration. Emigration can certainly be painful, but a young man with talent finds it stimulating. Outside your own nation, you lack a ready place. You need great ingenuity and effort just to find a niche. Hard work and ingenuity become a habit. Often they are enough to earn you a place above natives of your adoptive country quite as talented as you."

     Now cognitive psychologist Richard E. Nisbett's new book "Intelligence and How to Get It - Why Schools and Cultures Count"  has presented a compelling argument that the IQ differences between races are entirely environmental in origin.
     In particular, he has chapters on both the Jewish and Asian cultures (Jews and Asians score the highest on IQ tests) For those interested in education, and also for parents who desire to provide their children with the best educational opportunities, I would think this is a must read book. (Incidentally, Nisbett analyzes the alternate view -- that the difference is purely genetic – and in particular critiques the arguments made in the “The Bell Curve”)

March 1, 2009
     If you value your freedom of speech, you should be aware of the attempt in the United Nations to seriously restrict it:

     http://www.youtube.com/watch?v=Ji-qdC5zYd4 

     The UN resolution passed last year as a non-binding resolution and now they want to make it binding...As mentioned in the video, this resolution has nothing to do with promoting tolerance, but actually the exact opposite -- if that actually needed to be pointed out. 
     Any religion(s) that attempts to take away my freedom of speech richly deserves to be criticized.

    January 20, 2009
     PBS has announced a new film on the great J. Robert Oppenheimer to be aired January 26, 2009.
     It will be extremely difficult for the PBS to surpass the excellence of the BBC version "Oppenheimer, the Father of the Atomic Bomb", starring Sam Waterston. The BBC version is spellbinding drama that is also accurate historically. And, all the actors actually physically resemble the people they portray. 
     Even Edward Teller, in the forward to "Now It Can Be Told", by General Leslie Groves (Groves was the general in charge of the Manhattan Project), expressed his opinion that the seven-hour BBC production was the best of the television dramas on Oppenheimer and Los Alamos.
     What the PBS can pack into a mere 2 hours we will have to wait and see.
     Incidentally, the DVD version of the BBC film has an amazing 26 minute interview of Opie at the Institute for Advanced Study at Princeton, NJ, where he was the director. The famous Oppenheimer charm and intelligence is obvious.

October 28, 2008
     Sarah Palin attacks fruit fly research:

Sarah Palin's War on Science
http://www.youtube.com/watch?v=HCXqKEs68Xk
 
    Palin's motivation for this attack may have been benevolent, since she perceived a waste of tax payer monies, but she has unfortunately  only revealed her lack of knowledge of the importance of fruit fly research.

Bertand Russell once defined his concept of the good life as one that was inspired by love and guided by knowledge:
     "Knowledge and love are both indefinitely extensible; therefore, however good a life may be, a better life can be imagined. Neither love without knowledge or knowledge without love can produce a good life. In the Middle Ages, when pestilence appeared in a country, holy men advised the population to assemble in churches and pray for deliverance; the result was the infection spread with extraordinary rapidity among the crowded masses of the supplicants. This was an example of love without knowledge." ---    Bertrand Russell, 'What I Believe"

Palin does not understand foreign policy and events. She does not seem to understand science. Russell's observation would seem to be appropriate here.

October 8, 2008
     Bell Labs' parent company has shut down fundamental physics research:

The Bell Tolls For Bell Labs
Bell Labs Kills Fundamental Physics Research

    In the long run, it is obvious this can only have a negative effect on Bell Labs' ability to innovate and compete, and ultimately, on Bell Labs' bottom line. Historically, innovation has flourished in the fertile environment that is provided by basic research. Research into ideas that do not immediately have any obvious applications often unexpectedly yield tremendous applications.
    For example, the second link above mentions the GPS system, which relies on the hydrogen maser which in turn was dependent upon basic research into optical pumping. Interestingly, the author failed to mention that GPS critically relies on Einstein's theory of general relativity, which perhaps is the ultimate example of pure research without regard to any possible applications.
     GPS is comprised of 24 satellites orbiting the earth, all of which must have synchronized atomic clocks.  Determining your position on the earth requires the use of 4 of the satellites-- 3 for your longitude, latitude, and altitude, and the fourth to verify the accuracy of the clock in your GPS unit. Since clocks run at different rates depending on the strength of the gravitational field they are in -- and since gravity varies with satellite height -- general relativity must be used.
     But wait; there is even more fundamental research present in the GPS system. The whole idea of stimulated emission, on which masers and lasers depend, was discovered by Einstein in 1916. The 1916 paper, "Emission and Absorption of Radiation in Quantum Theory" (Zur Quantentheorie der Strahlung), like all of Einstein's research, was basic research.
    Here is an example of pure research having great applications in chemistry and medicine...
    The Bell Labs decision is obviously bad, and whoever is responsible for it should be fired.

September 25, 2008
         The large hadron collider (LHC) experiment in Geneva has been postponed. The worries of some that the LHC will generate a doomsday black hole that will swallow the earth are groundless. The doomsday black hole calculations are based on the purely theoretical and speculative assumption of extra large dimensions.
     This is not the first physics experiment that has been accorded the possibility of destroying the earth. At Los Alamos, the possibility had occurred to Teller that exploding an atomic bomb could in fact produce enough heat to ignite the earth's atmosphere in a thermonuclear reaction. Therefore, prior to the first atomic test in 1945, Teller, Marvin, and Konopinski analyzed this possibility in a classified Report LA-602 for Los Alamos. Of course, they concluded that the bomb would not ignite the atmosphere, although on first blush the idea is plausible. Even after the Teller, Marvin, and Konopinski report became declassified in 1973, people were still claiming this as a possibility -- most famously H.C. Dudley in the November 1975 issue of the Bulletin of Atomic Scientists.
     The main candidate reactions for igniting the atmosphere involves nitrogen:

      N¹⁴+ N¹⁴   --> Mg²⁸ + He⁴  + 17.7 MeV
or
       N¹⁴+ N¹⁴ -->  O¹⁶ + C¹²   + 10.6 MeV

     So can either reaction be made to happen? Well, theoretically, yes.

      In the first reaction, the Coulomb energy that is required to bring the nitrogen nuclei close enough for the strong force to kick in is less than energy released. It is energetically favorable and could, theoretically, be self sustaining. 
     In the second reaction, the nitrogens do not even have to be brought together, only a deuteron need be transferred from one nitrogen to the other. This is also energetically favorable.
      However, the reason the earth's atmosphere does not ignite in an atomic blast is because there are a couple of non-obvious mechanisms present that drain energy. For example, part of the energy is lost to the electrons in "braking radiation" (bremsstrahlung), which means it gets converted to light and cannot be used to sustain the reaction. Other atomic processes, such as the inverse Compton effect, also drain energy.
     It is interesting to contrast Report LA-602's scientific analysis, which is based on established scientific theories, and the doomsday black hole calculations, which are not based on anything but conjecture and speculative theories.
   (For a more complete analysis, including the possiblity of igniting the hydrogen in the world's oceans, see "Ultimate Catastrophe?"  in The Road from Los Alamos by Hans Bethe, pg 30-33)

September 11, 2008
     When the first president of Israel, Chaim Weizmann died in 1952, the presidency was offered to Albert Einstein. He declined, citing both a lack of experience and ability...
     ...and now, the Sarah Palin interview:
http://www.youtube.com/watch?v=WaMJ-xTcGxI
http://abcnews.go.com/Politics/Vote2008/Story?id=5782924&page=1

    Gibson was clearly antagonistic -- Palin gets credit for demonstrating poise under fire. Unfortunately, she also exhibited a dismal knowledge of current events and foreign policy.
     So, when Palin claims Russia invaded Georgia "unprovoked" (she said this twice in fact, after Gibson asked for clarification), she is showing she is simply unaware that it was Georgia who first sent troops into South Ossetia, and the Russian invasion was the response. Bush's real time assessment of the situation was quite accurate, when he said that Russia's response was disproportionate, meaning that Russia had indeed been provoked, only that the extent of the Russian response was excessive.
     Regarding foreign policy -- a candidate for VP of the United States should know what the Bush Doctrine is -- that she does not indicates that she was insufficiently vetted by McCain. Palin's claim that she has both the experience and ability to be president, in retrospect, seems ridiculous.  
 
September 4, 2008
     Sarah Palin in her native state:
http://www.youtube.com/watch?v=QG1vPYbRB7k
 Someone has suggested that if you close your eyes and just listen to the speech, she sounds like a 16 year old school girl. That is overly harsh. In fact, I would claim that most 16 year old school girls do not sound like religious zealots.

August 3, 2008
     Alexander Solzhenitsyn (December 11, 1918 - August 3, 2008)
Solzhenitsyn studied mathematics and physics at Rostov, but his experience at the hands of the Stalinist regime caused him to become a strong critic of the Soviet era. His "The Gulag Archipelago" is perhaps his most famous work.
     The premier Russian television station, Channel 1, opened its morning broadcast Monday morning with the Solzhenitsyn story and in fact gave rather extended coverage. Channel 1 showed Solzhenitsyn interviews, books, public appearances, and even meetings of Solzhenitsyn with Putin and the Pope...Not too bad for a man who was once stripped of his citizenship and then forced to leave his country. Russian president Medvedev (the name "Medvedev", if you must know, translates to English as "Bear") expressed his condolences.
     Only Putin's interrupting of live broadcasts of Russian television in April 2007 to announce the death of the great Russian Cellist, Mstislav Rostropovich, who incidentally was also exiled from Russia, partly because of his support for Solzhenitsyn, compares with this reclamation of Solzhenitsyn.
    Here is a Russia Today video about Solzhenitsyn.

July 17, 2008
     Fans of Richard Dawkins and Steven Weinberg will find a new interview here, in which Dawkins interviews Weinberg.

June 3, 2008
     At the University of Waterloo Bjarne Stroustrup discusses the new language features in C++0x and the reasons for their adoption. He also touches on garbage collection (and the associated performance hit), generic programming, and multi-core programming. He mentions that he is writing a new book on programming with C++ for beginners as a result of his having to teach freshman Texas A&M University students, which was a new experience for him. "Programming: Principles and Practice Using C++" by Bjarne Stroustrup is now available for pre-order on Amazon.

May 26, 2008
     Here in a recent interview, Donald Knuth expresses his views on open source, unit testing, literate programming, extreme programming, code reuse, and multicore programming.  Knuth's objection to multicore programming was surprising, as it has already been addressed by Intel with the release of its TBB library -- it is too bad the interviewer did not ask him about TBB. Knuth's main complaint was that the multicore code would have to be changed substantially every few years due to the inevitable hardware changes. IF the programmer is using TBB, that is not the case. (TBB is not a panacea, however, because the fastest multicore programs will be always be coded with raw threads and not TBB, and in that case you do have to consider the hardware and Knuth's observation would apply.) His other objection was that the majority of programs he writes would not benefit (presumably, because they were not easily parallelizable, or the gain would be minimal due to Amdahl's law) This "nobody needs more than 1 core" sentiment is strangely reminiscent of Bill Gates "nobody will ever need more than 640K RAM" statement.

May 21, 2008
      The great Hungarian-American physicist Eugene Wigner attributed the brilliance of his generation of Jewish Hungarian physicists (i.e., he had in mind Szilard, Teller, von Neumann and himself, a.k.a. "The Martians" as they were sometimes called during the Manhattan project) partly to the superior Budapest schools ...
Here Steve Ballmer gets to experience the Budapest schools first hand:
http://www.youtube.com/watch?v=S30WdoEHCH4
http://www.youtube.com/watch?v=npYsmDQs4C0&NR=1

February 27, 2008
     Bobby Fischer -- (March 9, 1943 – January 17, 2008)
It is perhaps a little too easy to find controversial items on the web about the late, great former world chess champion Bobby Fischer, but here and here are pages showcasing Bobby in a favorable light.

"On the chessboard lies and hypocrisy do not survive long. The creative combination lays bare the presumption of a lie; the merciless fact, culminating in a checkmate, contradicts the hypocrite." - Emanuel Lasker

The above Lasker quote (Lasker was not only a great world chess champion and mathematician, but was also a good friend of Einstein) Fischer selected for the introduction to his classic "My 60 Memorable Games". While Fischer had always been popular in Russia and the FSU, somehow the Lasker quote did not survive the Russian translation of his book.

January 9, 2008
     Mr. Wizard -- (July 10, 1917 -- June 12, 2007)
      In a classic episode, Mr. Wizard explains heat transfer.

December 11,2007
     http://www.youtube.com/watch?v=nTbeHTgr_TQ
      Steven Weinberg -- 1979 Nobel Prize Physics

      Nobelprize.org launches TheNobelPrize channel on YouTube:
      http://nobelprize.org/nobelweb/pressroom/youtube.html

December 3, 2007
    http://www.youtube.com/watch?v=U3tgY_eI_P0
    http://www.youtube.com/watch?v=q6Wrhivp7eQ  

      One man with courage makes a majority. -- Andrew Jackson

November 29, 2007
     http://www.youtube.com/watch?v=5-fjtSxOUes

     No god and no religion can survive ridicule. No church, no nobility, no royalty or other fraud, can face ridicule in a fair field and live. -- Mark Twain

October 4, 2007
     The October issue of Physics Today contains an insightful discussion of "quantum factoring facts" by N. David Mermin. In it, he explains the probabilistic method by which Shor's "factoring" algorithm actually works. Anytime one can find a discussion of quantum computing by a physicist of Mermin's quality, then there is a fair chance it will contain something of interest. (As a reminder of the relevance of quantum factoring, remember the security of the widely used RSA cryptosystem is thought to depend on the difficulty of factoring large numbers...quantum factoring would effectively render RSA broken)
      Before retiring, Mermin taught quantum computation at Cornell to computer science students. Note the class was not taught by a faculty member of the CS department. His book is available free here. The book could be a lot better in terms of explaining the physics  and mathematics of QM, but his goal seems to be just to give the CS student the minimum material needed to dive into quantum computation. Particulary interesting in chapter 2, is the following quote:

But a major part of the miracle is only apparent. I did not say that the result of the calculation is 2n evaluations of f, though many practitioners of quantum computation are rather careless about making such a claim. All I said (and all one can say) is that those explicit evaluations occur in the form of the state that describes the output of the computation. Before drawing extravagant practical or only, as many practitioners of quantum computation are wont to do, metaphysical conclusions from quantum parallelism, it is important to remember that when you have a collection of Qbits in a definite but unknown state, there is in general no way to nd out what that state is. If there were a way to learn the state of such a set of Qbits, then I myself would join in the rhapsodic chorus. (Typical verses: "Where were all those calculations done? In parallel universes!" "The possibility of quantum computation has established the existence of the multiverse." "Quantum computation achieves its power by dividing the computational task among huge numbers of parallel worlds.") But there is no way to learn the state. The only way to extract information from Qbits is to subject them to a measurement.

     Mermin does not parrot the erroneous interpretations that can readily be found in many quantum computation books, and this is refreshing indeed.


August 18, 2007
     Quantum algorithms and computation, by using the properties of quantum states, have achieved some impressive theoretical results. Grover's search algorithm, for example, is order N^1/2as opposed to the classical result of order N. So, if you had a list 10000 items to search, classically (by classically, I mean using a digital computer which implemented its logic using classical digital circuits and gates), it would take you, on average, N/2 steps, or in our case 5000, to find the item you were searching for... With the Grover search algorithm, you would need only 100 steps. Yes. Only 100.
     To achieve a basic understanding of how quantum algorithms work, it is not necessary that you understand all of quantum mechanics but only a very small subset of QM. You need to understand qubits. Qubits are the quantum mechanical version of the classical bit, and you would need to know how they combine, evolve and are measured quantum mechanically. This basic understanding often requires no more than simple linear algebra (or multi-linear for multi-particle systems). With this small subset of quantum mechanical knowledge, you can "turn the crank".
     Every book on quantum computing I have encountered attempts to explain the physics behind the crank.  However, for whatever reason (I cannot just believe it is because it is computer scientists that are writing about physics, because many of these books have physicist co-authors who should know better), every one of these books have been wrong when it comes to explaining photon interference. Photon interference is used to illustrate how interference in quantum mechanics differs from the classical case. Unfortunately, most incorrectly state that a photon can interfere with itself, and one book gets even weirder by saying that it is the photon paths that interfere. Evidently, none of the physicist authors were aware of Roy Glauber's (the 2005 Nobel laureate in physics for his work in quantum optics) January 1995 letter to the editor in the American Journal of Physics which clarified photon interference once and for all. I now partly quote from Glauber's letter:

Glauber first identifies the source of the confusion, the great Dirac:

"The source of trouble is a statement by Dirac...'Each photon interferes only with itself. Interference between two different photons can never occur.'"

And Glauber ends by summarizing what really happens:

"The things that interfere in quantum mechanics are not particles. They are probability amplitudes for certain events. It is the fact that probability amplitudes add up like complex numbers that is responsible for all quantum mechanical interferences. When the event in question represents the detection of a single photon, one can easily slide into the statement that the photon is interfering with itself. When one deals, on the other hand, with two-photon states, one still encounters many species of interference effects, but it would generate intolerable confusion to interpret these photons as interfering with one another. It is not difficult, for example, by means of non-linear optics, to construct situations in which interference takes place between an amplitude for a single blue photon and an amplitude for another state with two red photons. Quantum mechanics allows such interferences and a great many other varieties as well, but no one could sensibly speak of photons as interfering with themselves or any others in that sort of context.
     To sum it all up, these three papers are out in left field. It is time to put the famous dictum to rest, to remember Dirac and to honor him for his wonderful contribution to physics, and to forgive him for writing down in the early days of quantum mechanics a highly simplistic remark which has sowed confusion among physicists ever since"

Enough said. Photons do not interfere with themselves, no matter how many quantum computing books claim otherwise.

August 11,2007
     As always, you must be careful believing what you read on the web, and science journalism is no exception to this rule. Here , for example, is a recent article in Scientific American that makes the false statement that a quantum compupter "allow hackers to crack today's toughest coded messages". As there are cryptosystems that are known to be completely secure, although they are not typically used, we see that the author has either been mislead by the researchers or he is trying to make the result more sensational than it is. The most disappointing thing is that the article appeared in Scientific American, which I had considered held itself to a high scientific standard.