Talk:Problem Set 2

1/28/ @ 3:39pm (Vlad)

Sorry for omitting the prefactor in the definition of the compressibility. What you say is right, and I corrected the Web site. I was a bit sloppy, since such a prefactor is a finite number near a critical point, and does not influence the form of the critical singularity, i.e. the value of the critical exponent. Thanks also for noting the typos in the Van der Waals equation, which I also corrected. We can use the notation where $k_{B}=1$, but I do not understand what you mean by $N=1$.

1/28 @ 11PM:

I think I found a typo in the the lecture file that was used for our lecture about the Van der Waals equation given by Darko. The $T_{c}$ on the lecture file and given in class was ${\frac {8a}{27b^{2}}}$, however I arrived at ${\frac {8a}{27b}}$. I also checked some other websites that list the latter for $T_{c}$. Let me know if I'm wrong.

1/28 at 5:00 PM:

The negative is definitely missing but the 1/V is not necessary as that gives the fractional volume change. Also are we allowed to use the approximation where N and the Boltzmann constant are 1?

I think there is a factor of -1/V missing in the compressibility.