Introduction
摘要
The primary purpose of these notes is to understand the underlying structure behind a mathematically rich class of surfaces, and introduce how this comprehension leads to the principles of structure-preserving discretizations. We are particularly interested in the integrable structure they possess, as the modern surface theory is marked by the influence of integrable systems, and these properties extend to suitable discretizations of such surfaces. These lecture notes will focus on the case of isothermic surfaces in the context of Lie sphere geometry to achieve this goal.