Assume that the fermions are truly identical, including having the same spin orientations. Using equation 19.17, give a rough estimate of the energy of the Fermi surface in eV and the corresponding thermal temperatures, for each of the following systems:
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(a) conduction electrons in copper metal, for which there are about 8 × 1028 conduction electrons per cubic meter (comparable with the density of copper atoms);
(b) conduction electrons in aluminum. Its density is 2.7 g/cm3, its atomic mass number is 27, and each atom gives one electron to the conduction band.