Dispersion relation statistical mechanics

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SUMMARY

The discussion centers on the generalization of the Einstein and Debye Models in statistical mechanics, specifically addressing wave excitations with a dispersion relation defined as \(\omega(\vec{k}) = c |\vec{k}|^{\gamma}\) in dimensions \(d = 1, 2, 3\). Participants are tasked with determining the density of states \(g(\omega)\) for each dimension and analyzing the power-law relationships for energy \(E \propto T^{\alpha}\) and specific heat at low temperatures. The use of the delta distribution is suggested for solving the density of states in part (a), and a reference to Ziman's "Theory of Solids" is provided for further understanding of the Debye Model.

PREREQUISITES
  • Understanding of wave excitations in statistical mechanics
  • Familiarity with dispersion relations and their implications
  • Knowledge of the Einstein and Debye Models
  • Ability to work with partition functions in statistical mechanics
NEXT STEPS
  • Study the derivation of density of states in statistical mechanics
  • Learn about the specific heat capacity in relation to temperature in solid-state physics
  • Examine the single-particle partition function for harmonic oscillators
  • Review Ziman's "Theory of Solids," particularly Chapter 2, for insights on the Debye Model
USEFUL FOR

This discussion is beneficial for physicists, particularly those specializing in statistical mechanics, solid-state physics, and anyone interested in the theoretical foundations of wave excitations and their thermodynamic properties.

Luca2018
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Homework Statement
Consider general wave-excitations with a dispersion relations \omega(\vec(k)) =c |\vec(k) |^(\gamma) canpropagateind-dimensions(d=1,2,3)with wave-vector \vec(k).
a) Determine the density of states g(\omega) for each of the dimensions d =1,2,3and arbitrary γ>0.
b) What is the corresponding power-law at low temperatures for the energy
E \propto T^(\alpha) and the specific heat? (Hint: The independent modes of the wave- excitations can be described by the single-particle partition function for a harmonic oscillator).

Can you please help me? :)
Relevant Equations
I think you have to use the delta distribution to solve part a).
I know that this is the general case of the Einstein and Debye Model.
 
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Luca2018 said:
Homework Statement:: Consider general wave-excitations with a dispersion relations \omega(\vec(k)) =c |\vec(k) |^(\gamma) canpropagateind-dimensions(d=1,2,3)with wave-vector \vec(k).
a) Determine the density of states g(\omega) for each of the dimensions d =1,2,3and arbitrary γ>0.
b) What is the corresponding power-law at low temperatures for the energy
E \propto T^(\alpha) and the specific heat? (Hint: The independent modes of the wave- excitations can be described by the single-particle partition function for a harmonic oscillator).

Can you please help me? :)
Relevant Equations:: I think you have to use the delta distribution to solve part a).

I know that this is the general case of the Einstein and Debye Model.

Please see this link and rewrite your question for people to be able to understand.
 
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It seems to me like a generalization of the Debye Model. If you study the Debye Model (for example check Ziman's "theory of solid" chapter 2, but you can find it everywhere) you will see that it is assumed a dispersion relation of the form ##\omega = ck##; just substitute that relation with the one you are given and do the exactly same calculations.
 

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