Recent content by avarmaavarma

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    A What is De Broglie's Fictitious Wave?

    I read through DeBroglie's original paper - and also a modern explanation on the same (attached). The first contradiction that DeBroglie arrives at is simple enough - he considers the 'wave-particle' as observed from a stationary frame - and from a moving frame. The 'inner frequency' of the...
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    Solving a Relativistic Rocket Collision

    Try and work with 'velocity transformations' instead of position transformations. The collision takes place at the same SPACTIME event - not different events - regardless of which frame you choose. If rocket A has velocity Va (w.r.t EARTH frame) and B has Vb (also w.r.t EARTH) , then in A's...
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    How to Modify Names in an SQL View?

    You need to use 'ALTER VIEW' e.g. ALTER VIEW HumanResources.EmployeeHireDate AS SELECT p.FirstName, p.LastName, e.HireDate FROM HumanResources.Employee AS e JOIN Person.Person AS p ON e.BusinessEntityID = p.BusinessEntityID WHERE HireDate < CONVERT(DATETIME,'20020101',101) ; GO
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    QP Interpretation Hierarchy and Subclasses

    Try this text by John Wheeler...it is out of print..but still a classic. It attempts to categorize the various interpretations based on both underlying principles as well as ( not so recent) experiments. https://www.amazon.com/dp/0691613168/?tag=pfamazon01-20 If you need a quick read, look...
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    Which Books Focus on the Formulation of Differential Equations?

    Thanks. I do have such academic texts - and am able to find bits and pieces here and there. However, the closest thing I got to what I was looking for was -'Mathematical modeling techniques' a dover text. Am still curious to see if other books deal with this topic singlepointedly...thanks
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    Which Books Focus on the Formulation of Differential Equations?

    I have seen a few articles outlining the 'derivation' of certain differential equations - e.g. Heat flow equation, vibrating string wave equation etc. Does this correctly fall under 'mathematical modeling of physical phenomenon? Can anyone recommend a book that deals primarily with such...
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    Is there a better calculus textbook for self-study than Courant's?

    You might like these links : well written articles on people who treat math as a hobby http://www.3quarksdaily.com/3quarksdaily/2011/08/mathematical-learning-and-math-as-a-hobby.html http://www.anujvarma.com/mathematics-as-a-hobby-yes-really/
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    Clarification on light speed experiment

    http://physicsworld.com/cws/article/news/2810 Can anyone provide some clarification on this experiment? Is this just a case of 'phase velocity' surpassing group velocity? If so, why does the last paragraph in the article seem to point to FTL? "There is no widespread agreement among...
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    What is the effect of photon-electron collisions in X-ray imaging?

    There is no 'part' of the photon's energy! The smallest 'part' is the photon. There is no smaller part. If an electron's next energy level happens to be the exact same energy as this 'part', then it will readily absorb the photon. Otherwise it will not. It does not have an option to take part of...
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    What is the effect of photon-electron collisions in X-ray imaging?

    Hmm - kof9595995 - the photoelectric effect has a lot to do with the original question. The effect showed that the 'wavelike' thinking of light - that its energy could be absorbed in a continuous fashion - was incorrect. The idea of a photon having more than the exact energy that could be partly...
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    What is the effect of photon-electron collisions in X-ray imaging?

    That's exactly the basic concept in QM - if an energy 'quantum' isn't the EXACT right amount - nothing happens. No absorption - no part absorption. We need to move away from our 'continuous' energy absorption ideas when dealing with collisions in the microscopic world. Even the basic picture of...
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    What is the effect of photon-electron collisions in X-ray imaging?

    This time with the actual thread link... https://www.physicsforums.com/archive/index.php/t-178653.html
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    What is the effect of photon-electron collisions in X-ray imaging?

    In Compton scattering, photons are absorbed and re-emitted. Here is a thread that somewhat discusses this. There may be more references out there. The 'change' in wavelength in Compton scattering is due to the different energy photon that is emitted.
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    What is the effect of photon-electron collisions in X-ray imaging?

    Rayleigh scattering does not involve absorption or emission of photons. It is an elastic process - so the final energy of the photon is the same as its initial energy. The 'blue' photons have more energy and are scattered more (than say the red). Hence the sky appears blue. So - no real...
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    What is the effect of photon-electron collisions in X-ray imaging?

    B) is incorrect. The only transfer of energy occurs either wholly (one quantum = 1 photon) or not at all. It seems hard to visualize since intuitively, the photon should transfer some K.E. to the electron. In reality, no energy transfer happens unless a full photon is absorbed. Energy...
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