Recent content by read

  1. R

    I Classical chaos and quantum mechanics

    Still, I would like to ask further. More specifically, the correlators for CHSH are just -cos(angle(a,b)), and this is just because of Pauly matrix and singlet w.f. Now, for an angle like 135 degrees we get 2.sqrt(2), so 70% more than in classics. Why should we check CHSH inequality? If we think...
  2. R

    I Classical chaos and quantum mechanics

    I mean that the only fact that CHSH>2 calculated by QM, purely theoretically, is enough to prove nonlocality of QM. There is no need for specific experiments with entangled photons to see if this is experimentally confirmed.
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    I Classical chaos and quantum mechanics

    Reading the posts in this thread I thought that i could ask the following question. Do bell inequalities need explicit experimental verification in special experiments aimed to check the inequalities? The violation of the classical CHSH<=2 inequality for two spins 1/2 is based on...
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    What is the difference between monoclinic C and triclinic P lattices?

    In P1: a≠b≠c, all angles≠π/2, so to two-fold axis in C2/m a=b≠c, β≠π/2, γ≠π/2 for primitive basis and you still have 2/m axis going along the bisectrix between a and b
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    What are the physical implications of phonon softening?

    Phonon softening means that the energy of one of phonon branches ##\omega(k)## becomes zero at some point k0 of Brillouin zone. Phonon is a dynamical object related to the atomic vibrations. When its frequency goes to zero the vibrations become static, resulting in general in new crystal...
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    Rules in determining family of planes in Hexagonal

    1 2 3 -3 1 3 -3 2 3 -2 -1 3 -2 3 3 -1 -2 3 -1 3 3 1 -3 3 2 -3 3 2 1 3 3 -2 3 3 -1 3 and the same as above multiplied by -1. hope it helps...
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    Rules in determining family of planes in Hexagonal

    reciprocal lattice constants. Your basis is a*=[b x c]/V, b* =[c x a]/V, c* = [a x b]/V. V - is cell volume, a,b,c, - basis of the lattice. The hkl that you use are written in the above basis.
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    Rules in determining family of planes in Hexagonal

    24 is a maximal multiplicity when h # k # l # 0. For 110: -110, 0-10,-210,... 00-4 can be equal to -100 only accidentally. Look at the formula. There are also lengths a*, c* which are different.
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    Rules in determining family of planes in Hexagonal

    This number (24) is also called multiplicity. To calculate it we should calculate the length of your reciprocal lattice vector. In hexagonal case (hkl)^2 = a*^2(h^2+k^2+hk) + c*^2 l. Then we should look at which h,k,l the length remains the same. So the problem is reduced to h^2+k^2+hk=const...
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    Reciprocal lattice vector

    Just a comment. To be precise, the reciprocal lattice, i.e. its basis and any vectors G_hkl in this basis are completely defined by the real lattice basis, and independent on the details of atomic positions (i.e. the crystal structure). I think M Quack first sentence should be modified to "...
  11. R

    What is the best book for explaining X-ray diffraction theory and calculations?

    Vainshtein, vol I http://www.google.com/search?hl=en&client=safari&rls=en&biw=1202&bih=1185&q=vainshtein+modern+crystallography&oq=vainshtein+crystallography&gs_l=serp.3.0.0i22i30.62757.66933.0.68812.15.15.0.0.0.0.94.1134.15.15.0...0.0...1c.1.8.serp.Uu_OfuFQHWE
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    Rocket Launch: Upthrust Increasing?

    Thank you for calculations. I have also done similar thing, but I calculated Q' and T' differently. I use the frame of reference where the the rocket has speed V. Then, Q'= -m'(V_ex-V)^2/2 T'=((mV^2)/2)'=mVV' For T' we take derivative only for the speed, not mass, because we are...
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    Rocket Launch: Upthrust Increasing?

    Sorry "to maximize the factor:"
  14. R

    Rocket Launch: Upthrust Increasing?

    I mean that I want to maximally use the kinetic energy of the gases to accelerate my rocket. So, at the moment we do not care how much energy has been used to produce the mass flow. What strategy of velocity of emitted gases V_g(m) should I use to minimize the factor: K(m)/(K(m)+Q(m0-m))...
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    Rocket Launch: Upthrust Increasing?

    Hello BruceW, Might be you can help? Regarding efficiency of using fuel: K/K+Q, where Q=total kinetic energy of the emitted gases, K=final kinetic energy of rocket. Sometime ago I read in a popular book of http://en.wikipedia.org/wiki/Gerard_'t_Hooft"]Gerard[/PLAIN] [Broken] t'Hooft...
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