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In the case of inorganic matter, such as metal sheets, folding/creasing produces a substantial bulk stress in the material which can modify the molecular structure in a large number of complex (and not fully understood) ways. For example, it can break bonds, cause amorphisation, and propagate dislocations. These same mechanisms are at play when you cut a ...


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What happens during folding is that the material undergoes plastic deformation. When a sheet of material is bent slightly that deformation is usually elastic, meaning it will return to its original shape when the deforming stress is withdrawn. But when the deformation is larger we enter the plastic zone: the material will no longer fully recover its ...


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Plants harvest light with near perfect efficiency, but this is impossible under classical physics. Along the way to the photosynthzing core, photons should collide with other particles, but they don't. A photon reaching the core is as likely to succeed as you sprinting through a dense forest blindfolded trying to get to the center of the forest without ...


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Well, you might not really want to overthink it. It all hinges on the Pauli matrix $\sigma_1$ which, yes, is the permutation group with two components, with eigenvalues $\pm 1$ for $v^T=(1,1)$, symmetric, and $w^T=(1,-1)$, antisymmetric, respectively. Equivalently to your decomposition, you may write the hamiltonian as $$ H= \epsilon_0 I_4 + ...


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Nifty, The thermal velocity is velocity of thermal motion of particles which make up gas, liquid, and so on. Thermal velocity is a measure of temperature and is also measure of the width of the peak in the Maxwell–Boltzmann particle velocity distribution.


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The answer by Tom is correct. I would like to add a few more points about scattering phenomena. Using Raman spectroscopy rotation and vibration of these homo-nuclear molecules are easily probed. (Classically, scattering is explained by induced dipole moment; while Quantum-mechanical treatment is based on the Perturbation theory). However, Raman signal is ...



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