Indeed we can assign to each solid a characteristic temperature, known as the Debye temperature, θD, and then, if we express temperature not in kelvin but in units of the Debye temperature for th...Indeed we can assign to each solid a characteristic temperature, known as the Debye temperature, θD, and then, if we express temperature not in kelvin but in units of the Debye temperature for the particular solid, then the curves are indeed the same shape. In case you are wondering what the symbol “x” stands for in equation 8.9.1, it is merely a dummy variable, for the integral in that expression is a function not of x but of T, the upper limit of the integral.
