In this question, there is a nice intuitive explanation, why one uses weak solutions and what the intuition is behind the weak solutions: intuition behind weak solution
Is there a similar explanation for mild solutions?
Thank you in advance!
Best,
Luke
See Is a mild solution the same thing as a weak solution? , in which an example is given where a weak solution and mild solution for a particular problem coincide.
Mild solutions are weak solutions in the sense that they are not necessarily classical solutions. They are just a different way of getting a potential classical solution, or a substitute for a classical solution if none exist.