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  • Miscellaneous Topics for Physicists

    Posted on May 14th, 2009 admin No comments

    The concluding post for the curriculum review topics are below. Many of these are, in my opinion, more suitable in an elective or advanced graduate special topics course.

    • Cosmology and Astrophysics theory
      • Big Bang, inflation, CMB
      • Dark energy, dark matter
      • dark holes, neutron stars
    • Particle physics theory
      • Feynman diagrams
      • Standard Model and QCD
      • String theory
    • Nonlinear physics theory
      • Attractors and bifurcation theory
      • Bistability and hysteresis
      • Chaos
      • Hamiltonian and dissipative chaos, Poincare maps
      • Pattern formation and spatiotemporal chaos
      • Fluid dynamics
      • Turbulence
    • Condensed Matter
      • Semiconductors
      • Nanoscience
      • Superconductivity
    • Biophysics theory
      • DNA and proteins
      • Gene regulation
      • Structures and interactions
      • Biophysical techniques
      • Systems biology
    • Instrumentation, techniques, experiment
      • Microscopy: TEM, STM, AFM, NMR
      • Machine shop class
      • Experimental techniques
    • Computation
      • Numerical analysis/methods
      • Simulation and Monte-Carlo
      • Mathematica and/or Maple
      • Computational programming (C++, Fortran, etc.)
  • Mathematical Methods for Physics

    Posted on May 14th, 2009 admin No comments

    Topics in maths for physicists include:

    • ODE and PDE
      • 1st, 2nd order, Wronskian
      • Sturm-Liouville theorem, orthogonal series expansion
      • Qualitative methods, fixed points, flow, bifurcations
      • Legendre polynomials/ functions, spherical harmonics
      • Bessel functions, zeroes, asymptotic expansions
      • Laplace/Poisson, heat, wave mechanics equations
      • Boundary conditions, elliptic, parabolic, hyperbolic
      • Separation of variables
      • Orthogonal coordinates, grad, div, curl, \bigtriangledown^2
      • Laplace problems: rectangular, cylindrical, spherical
      • Green’s functions
      • Fourier series and tranforms
      • Laplace transforms
    • Groups and tensors
      • Discrete groups, C_n, D_n, irreducible representations
      • Lorentz group
      • Lie groups
      • SU(n), U(n), O(n), SO(n)
      • Cartesian tensors
      • General tensors
      • Contravariant/covariant derivatives and Christoffel symbols
    • Complex variables
      • Analytic functions and Cauchy-Riemann equations
      • Cauchy’s theorem and integral formula
      • Residue theorem and contour integration
      • Conformal mapping
      • Steepest descents
      • Integral equations
      • Neumann series, Hilbert-Schmidt theory
    • Probability Theory
      • Distributions: Binomial, Poisson, Gaussian
      • Random walks
      • Characteristic functions, central limit theorem
      • Stochastic process, Poisson processes
      • Mathematical statistics, chi-square, confidence intervals
  • I wanna GO to this SO MUCH!

    Posted on May 14th, 2009 admin No comments

    Darn it. First I miss the Two Cultures conference in New York this past weekend, and now I can’t even go to this event:

    The Pacific Science Center event is totally free, so go, go, go, and let me know how it went. Pleeez…

  • Questions for Aliens

    Posted on May 14th, 2009 admin No comments
    Navier-Stokes Equation

    Navier-Stokes Equation

    In the book A Demon Haunted World,by Carl Sagan, Sagan states he often received correspondence from people who claimed they were in contact with aliens. These people invited Sagan to ask the aliens questions. Sagan, the consummate scientist, always had some questions prepared.

    If there are aliens among us, it is reasonable to assume they’re from a more advanced civilization from ours. Assuming this, it is also reasonable to assume they would have the answers to questions that have stumped humans for years. Questions asked of aliens should be problems unsolved by humans, but where we would immediately recognize the answer as correct, or the answer could be proved. Asking “Is there a God” yields an answer that may not be recognized as correct by some people, and an answer that cannot be verified by scientific means. Unsolved mathematical problems would be excellent questions to ask of an advanced civilization.

    Here are a few questions I would ask of aliens:

    1. Please (it doesn’t hurt to be polite) solve Goldbach’s Conjecture. This is one of the oldest problems relating to prime numbers. Prime numbers are used in cryptography and internet security.
    2. Design an experiment to prove or disprove the existance of higher dimensions. Humans can see three spatial dimensions, and we move forward through the fourth dimension of time, but there are theories that include 11 dimensions.
    3. Why is gravity such a weak force when compared to electromagnetic, strong nuclear and weak nuclear forces? Provide an explanation that can be proved experimentally.
    4. Prove solutions to the Navier-Stokes equations including smoothness solutions. I went through 4 years of mechanical engineering and I just barely understand this. If you can explain this to me, leave it in the comment box.
    5. Please (again, it doesn’t hurt to be polite with a potentially superior life-form) give the composition and production methods to make a high temperature superconductor. I would hope the aliens would provide me with a superconducting material that would function at temperatures greater than 293°K (20°C) which is room temperature.

    These are the questions that interest me. A civilization that can travel vast distances though space in their UFOs should be sufficiently advanced to answer these questions. Next time you have contact with an alien, ask some questions and see what they come up with. If you get answers to questions that have remained unsolved by humans for hundreds or thousands of years, then maybe you’re corresponding with a real extra-terrestrial.

  • The "two cultures" debate lives on

    Posted on May 14th, 2009 admin No comments

    50 years ago (1959), novelist and trained scientist C.P. Snow wrote the Rede lecture “The Two Cultures.” In it, Snow expressed great concern over what he saw as a rift in the quest for knowledge. He saw people taking an either/or approach to learning. Either you approached it from a ”humanist” point of view, or you approached it from a “scientific” frame of mind. He also saw some aspects of knowledge emphasized over others.

    “At some point scientists had ceased to be considered intellectuals, Snow noted, and though any educated person was required to know Shakespeare, almost none knew the second law of thermodynamics.” [Seed Magazine]

    This concerned Snow a lot, as he obviously saw the benefits in his own life of cultivating both camps and bringing knowledge together, possibly forming a “third culture” of cultural scientists, assuming this rift couldn’t be patched.

    So where are we now, 50 years later?

    SEED Magazine interviewed several currently practicing researchers who through their careers have tried to bridge that gap, including E.O. Wilson (who wrote Consilience in 1998 to try and addresss the gaps), Steve Pinker (an avid bridge builder, even if I don’t agree with him all the time), and new up and comers.

    Personally, I fear that divide has only widened in the past 50 years. Some universities have divided their anthropology departments on the bio/culture lines, some science departments don’t understand the importance of good writing to their undergraduates, and most humanities undergrads try to avoid taking science and math as much as possible.

    Or are discouraged: I signed up for a biology class my first year in college, only to be told (repeatedly) on the first day of class “unless your major is nursing, biology, or other science major, you probably shouldn’t take this class.” The guy actually made us fill out little cards with our majors, and asked all those who weren’t majoring in nursing or biology to leave. Not because it was geared towards those particular majors, just because it was “hard.” (For the record, I got a C+ on my first test, got scared and dropped out. How many other kids do you think that happened to?).

    So, long story short, this is the main reason why I founded this blog: to combat the idea that the humanities, social sciences, and “hard” sciences can’t co-exist and benefit from each other. As the speakers say in their interviews, we are starting to bridge gaps across the divide, we are starting to see that these things are connected and can benefit from each other. But after more than 50 years of a growing divide, it is going to take a little work to patch things up.

  • Kuota Aman

    Posted on May 14th, 2009 admin No comments

    Dengan melanjutkan kelas di hari Jumat besok, kepada seluruh anggota perkumpulan plan B maupun plan

  • The Opposite of War…

    Posted on May 14th, 2009 admin No comments

    “The opposite of war isn’t peace — it’s creation!” (8:05-8:10)

    Mark, a protagonist in the hit musical RENT, declares as much in the midst of a song that boldly celebrates an idealized 1990s-era New York bohemia, a paen to all things queer, questioning or just a little bit left-of-center. I heard the song again quite recently while riding in a friend’s car, when this one line in particular stood out from all the others and set me thinking. It’s probably as a result of my recent exposure to things like physics theory and logic (damnable liberal arts education), but the lyrics made me pause to decide if the claim they make is true. And I think it is. Allow me to explain:

    First, I should state that I am mildly obsessed with the philosophy and morality of war. I’ve spent years now toying with the same question, specifically asking whether war is an intrinsic human behavior, and I remain convinced that it is. War is a natural expression of our competitive urges as a species made manifest by our reliance on tools and technology, derived from our supposed intelligence. My only comfort in this rather fatalistic point of view is that the same intelligence that lets us build weapons also, in theory, allows us to overcome our base instincts and choose a higher road. It does not always happen, but it sometimes does. This helps to get me through the day when I think about war.

    But as I’ve moved beyond simply the intrinsic nature of war, there have been many more questions, including the idea I am address today. What IS the opposite of war? When we are not in a state of war, we are assumed to be in a state of peace. That seems logical enough, and I think that most reasonable people would both offer and accept “peace” as the opposite of war. But the answer may not be sufficient for the philosopher or the non-philosopher who spends too much time thinking about obscure topics. Fortunate indeed for my overthinking that the question was raised with an answer in the same statement. The only task at hand, then, is to show why I agree with the answer provided.

    Since we are considering synonyms and antonyms, it is appropriate first to describe and define which words are key to this discussion. I’ve focused on four words: war, peace, creation and motion. Motion becomes pivotal later. Before I explain the significance of motion, let us look at our other three concepts. Merriam-Webster offers us the following definitions, with the most relevant parts in bold:

    war:

    1 a: (1): a state of usually open and declared armed hostile conflict between states or nations (2): a period of such armed conflict (3): state of war b: the art or science of warfare

    2 a: a state of hostility, conflict, or antagonism b: a struggle or competition between opposing forces or for a particular end <a class war> <a war against disease> c: variance, odds 3

    peace:

    1: a state of tranquillity or quiet: as a: freedom from civil disturbance b: a state of security or order within a community provided for by law or custom <a breach of the peace>

    2: freedom from disquieting or oppressive thoughts or emotions

    3: harmony in personal relations

    4 a: a state or period of mutual concord between governments b: a pact or agreement to end hostilities between those who have been at war or in a state of enmity

    creation:

    1: the act of creating ; especially : the act of bringing the world into ordered existence

    2: the act of making, inventing, or producing: as a: the act of investing with a new rank or office b: the first representation of a dramatic role

    3: something that is created: as a: world b: creatures singly or in aggregate c: an original work of art d: a new usually striking article of clothing

    So war can be defined as a state of hostility, usually armed conflict but also antagonism as relates ideas and concepts, peace is a state of tranquility of various sorts, and creation is the act of creating or making. Creation in this context becomes especially important because of the secondary definition, “especially: the act of bringing the world into ordered existence”. If war is a state of armed conflict or an agitated dispute between factions and ideas, there is destruction inherent in the concept of war. In this view, peace is not the opposite of war so much as the absence of war, and the antonym — or antithesis — of war/destruction is creation.

    Now, peace is a fine environment for the creation of things, but we can find many examples of creation (in a very broad use of the word, as I am willing to apply it to the establishment of the European Union as much as in any artistic or traditionally ‘creative’ sense) in times and places where war/destruction has been dominant. Turbulent periods seem to often allow new endeavors or ideas to flourish, either because they require a reaction that is often expressed in creative/constructive ways or because an old order falls away in part or in whole and something new is thusly necessary. It is a fair conclusion, then, to say that war is an action — it requires active will and participation. Peace is an (enjoyable) absence of this sort of action, but may also become the absence of any positive action as well. And it is here that my final judgment that creative IS the opposite of war comes full circle, thanks to a very rudimentary familiarity with physics theory.

    It may be a silly thing to do, but I would argue that there is more depth to this idea of war and creation as polar opposites than just the choice of words one can use — after all, I have even acknowledged that peace is a fine answer to the idea of war’s opposite. But I cannot escape the point that war is an active concept, one with will and intent behind it… one which requires a kind of motion. Let’s consider the definition of motion, again with bold for emphasis on what really concerns us:

    motion:

    1 a: an act, process, or instance of changing place : movement b: an active or functioning state or condition <set the divorce proceedings in motion>

    2: an impulse or inclination of the mind or will

    3 a: a proposal for action ; especially : a formal proposal made in a deliberative assembly b: an application made to a court or judge to obtain an order, ruling, or direction

    Further, when discussing motion, it is always important to ground that understanding in science. The history of physics theory (as I understand it) is such that Newton’s laws have been superseded by more recent theories which describe contexts that Newton simply never encountered. Nevertheless, they remain generally sound and applicable in some cases, and are still key to the history of physics theory. And, as we are not discussing the finer points of physics theory but instead another way of thinking about what has been a primarily linguistic argument, the Laws of Motion should suffice for this purpose. And, I offer Newton’s Third Law, Latin first, to provide a more specific framework in which to consider motion:


    Lex III: Actioni contrariam semper et æqualem esse reactionem: sive corporum duorum actiones in se mutuo semper esse æquales et in partes contrarias dirigi. (For a force there is always an equal and opposite reaction: or the forces of two bodies on each other are always equal and are directed in opposite directions.)

    This classic theorem provides a new frame of reference from which to consider our topic. It is a common use of the Third Law of Motion to describe not only scientific forces, but also concepts in larger culture: science and faith, liberal and conservative, or, as we consider here, war and peace. From the perspective offered by the Third Law and its more literary usage, if we accept the definitions of peace as a state of tranquility, then it becomes a state that lacks force. Since war, by its very nature, is a forceful state (or one, in a sense, in a state of motion), then Newton’s law may also tell us we require an equal and opposite reactive force. As above, I would contend that the only suitable opposite of war is creation.

  • Length

    Posted on May 14th, 2009 admin No comments
    Refocusing a camera lens onto radioactive material.

    Refocusing a camera lens onto radioactive material.

    Going farther into physics theory results in some interesting numbers.

    The mass of the sun is 1.48 kilometers.

    The mass of an electron is 0.510 mega-electronvolts.

    And of course the greatest equation relating the speed of light and Newton’s gravitational constant:

    c = G = 1

    The great thing about the above equation is that everything can be measured in terms length and units no longer pose a problem, just add them in until the equation balances.

    And compared to the sun the earth has a mass of 0.443 centimeters.

  • Today in Gigapedia… // Hoy en Gigapedia

    Posted on May 14th, 2009 admin No comments

    [English]

    A lot of new Gigapedia items for today.

    ——————————————————————————————-

    [Español]

    Hoy Gigapedia nos trae un montón de novedades.

    ——————————————————————————————-

    I want to look at the new items!

  • Warp speed travel might be in your future

    Posted on May 14th, 2009 admin 1 comment

    OPINION By LEE DYE

    May 13, 2009 —

    warp_speed_090512_mnHere’s the good news for all those “Star Trek” enthusiasts out there — a couple of physicists think they’ve figured out how to travel faster than the speed of light without breaking the laws of physics theory.

    But here’s the bad news — we may have to sacrifice Jupiter to get there.

    Gerald Cleaver, associate professor of physics theory at Baylor University, and his post-doctoral researcher, Richard Obousy, have combined some of the most elusive fields in physics theory, including string theory and general relativity, to concoct a scheme to move “Star Trek’s” warp speed a little closer to reality. Very little, that is.

    The folks who produce the “Star Trek” flicks have never explained how the good ship Enterprise can speed through the universe faster than a beam of light. That minor achievement is necessary if humans are ever to explore the galaxy’s back yard, not to mention the distant reaches of the universe.

    The only problem is Albert Einstein said it couldn’t be done.

    “Objects that have mass cannot travel at the speed of light,” Cleaver said in an interview. According to Einstein’s famous equation, “as an object travels faster and faster, its mass increases,” he added. “As an object approaches the speed of light its mass becomes infinite.”

    Read the rest of this entry »