# List All Events

Mathematical Physics Seminar

## Entropy and entropoids

#### Daan Frenkel - University of Cambridge

Location:  zoom
Date & time: Wednesday, 16 June 2021 at 10:45AM - 11:45PM

The term entropy is increasingly used to denote measurable or computable  quantities that only have some of the properties of the entropy of Clausius, Boltzmann and Gibbs. Whilst  "entropoid" quantities may be interesting in their own right, it is important to be clear about what they are, and what they are not.

In my talk, I will discuss several entropy-related quantities from a computation perspective. In particular, I will discuss  Edwards' "granular entropy" , i.e.  the logarithm of the number of distinct packings of N granular particles in a fixed volume V, Computable Information Density, and (if time allows) the free energy of well equilibrated glasses.

The methods to compute (or at least estimate) these entropoid quantities have evolved in recent years. That development makes it urgent to look critically at their credentials as an entropy.