"...at its fundamental level, the model is built on the concept of a geodesic distance, which belongs to geometry. At its phenomenological level, the theory takes as the input parameters geometrical (mechanical) characteristics of a thermal system, the (average) inter-atomic distance and the velocity of sound in condensed matter, and gives as the output an observable quantity, specific heat function. It is reasonable then to call it a geometrical theory, after all geometry is physics."