Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2024/iii/paper-107/1/c/solution

One useful form of the Simon absorption lemma is the following. Let be nonnegative and subadditive on balls contained in , and suppose that for every such ,
where is also subadditive and is smaller than a constant depending only on and . Then
More generally, an additional controlled remainder on the right remains with a dimensional constant. The proof covers by finitely many smaller balls, sums by subadditivity, and iterates so that the term is absorbed.

New to topics? Read the docs here!