Recent content by niklaus

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    Comp Sci How can I calculate pi in Fortran without using intrinsic functions?

    Your loops don't calculate anything like sin(x) or cos(x) at the moment. I am not sure if you are trying to implement the taylor expansions of sine and cosine (a good idea in my opinion), but if you are, 9000 terms would be total overkill. 10 should be plenty for your purposes. Hint about...
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    Comp Sci How can I calculate pi in Fortran without using intrinsic functions?

    Quick and dirty (but inefficient): Do a loop that increases x by a small amount every time, calculate sin(x) and cos(x), compare them, if they fulfill the condition, congratulations you found pi more sophisticated: do large increments while sin(x) < cos(x), as soon as cos(x)>sin(x) decrease...
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    Quitting Physics: Is it Time to Move On?

    Those stories are mostly based on a misunderstanding of the grade scale used in Switzerland vs. Germany. Both use numbers 1-6, but whereas in Germany, 1 is the best grade, in Switzerland (where Einstein went to high school) 6 is best. Some german biographer was not aware of this and the rumor...
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    Who first solved the hydrogen atom in quantum mechanics?

    Schrödinger did it in 1926 too, his paper was received January 27. E. Schrödinger: „Quantisierung als Eigenwertproblem I“, Annalen der Physik 79 (1926).
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    Is the Rise of Psychics a Sign of Growing Interest or a Dangerous Trend?

    Publicity for who? What it shows is that too many people don't understand very basic science and prefer to believe in magic.
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    Is astrology an art or a science?

    Well, just because people started paying attention to the stars for stupid reasons doesn't mean that astronomy still somehow depends on those superstitions.
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    Regarding pair production and annihilation

    Throughout all these reactions, energy must be conserved. In order for pair creation to happen, the photon must have at least enough energy to create the two particles (2 times 0.511 MeV). So you can certainly turn the kinetic energy of the original pair into additional pairs of particles (if it...
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    Learning Quantum Mechanics: What Books to Start With?

    Study some linear algebra, it's as crucial to QM as calculus is to classical mechanics. All the rest of the necessary math should be covered in a QM text just fine.
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    Current physics topics highly debated over?

    I wonder if topics in physics are very suitable to this kind of treatment... The debate about some current topic is probably going to be rather technical and not easy to get into. If it has to be physics, one thing that comes to mind is the recent result from the OPERA experiment that measured...
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    Do you prefer concise or long lectures?

    4 hours in one sitting? that seems crazy... I'm used to 2 x 45 minutes with a 15 min break in between, which works fine for me. Since it takes me about an hour to get to university, anything shorter than that makes the travel time to lecture time ratio look bad.
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    Gravitational force of antimatter

    Yes, it would be a big surprise if it wasn't the same, but we don't know for sure until we measured it.
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    Gravitational force of antimatter

    There is an experiment in the works at CERN that attempts to measure the effect of Earth's gravity on a antihydrogen beam. I don't think there are any results yet, but here is the website: http://aegis.web.cern.ch/aegis/home.html
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    Courses Theoretical physics Graduate courses - is it all string theory?

    Maybe I'm reading this wrong, but this sounds like you believe that all theoretical physicists are looking for a theory of everything. This is not the case at all. Just pick a random university and check the website of their theoretical physics department to get an idea of the variety of topics...
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    Do Photons Have Mass? - Debate & Questions

    Also a brief answer: The quanta of sound waves are called phonons (at least when they occur in condensed matter). They also exhibit some particle-like properties.
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    Question on Landau and Lifshitz volumes

    For volume 1, you should be ok with multivariable calc and differential equations, plus a bit of linear algebra (eigenvalues and stuff). They have pretty high expectations as far as computational calculus skills go, especially to solve the problems. It probably helps to be familiar with the...
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