Bose Systems - Delaware Physics

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Chapter 7Bose SystemsIn this chapter we apply the results of section to Systems of particlessatisfying bose -Einstein statistics. The examples are Black Body radiation (thephoton gas), atomic vibration in solids (the phonon gas) and alkali atoms intraps and liquid4He (a bose gas and fluid). Bosons in traps and the superfluidstate of liquid4He is believed to be an example of bose -Einstein condensationin which a large fraction of the Bosons occupy (condense into) the ground Body RadiationWe are all familiar with the idea that hot objects emit radiation a lightbulb, for example. In the hot wire filament, an electron, originally in an excitedstate drops to a lower energy state and the energy difference is given off asa photon, ( =h = 2 1). We are also familiar with the absorption ofradiation by surfaces. For example, clothes in the summer absorb photons fromthe sun and heat up. Black clothes absorb more radiation than lighter means, of course that lighter colored clothes reflect a larger fraction of thelight falling on black body is defined as one which absorbs all the radiation incidentupon it a perfect absorber.

Bose Systems In this chapter we apply the results of section 5.3 to systems of particles ... What is the energy density, u = U=V, of this photon gas equilibrium? How ... states (†n = nh”) rather than integrating over a continuous set of states. This mathematical result was interpreted physically by Einstein in 1905, using the photoelectric ...

  States, System, Density, Of state, Bose, Bose systems