S 10.1 Lemma

[Issra]

Posted here since there is no section for Chapter 10.

In Lemma 1 in S10.1, why is the condition $\phi(t_0) = \phi(t_1) = 0 $ necessary?

[Victor Ivrii]

This condition is not necessary. However more conditions to $\phi$ lead to a lesser class of admissible $\phi$ in the assumption  and thus to weaker assumption of Lemma 1, and thus to stronger and more general statement.