# Lipschitz Continuity and Uniqueness

1. Sep 7, 2005

### Kajsa_Stina

Dear all,

If a differential equation is Lipschitz continuous, then the solution is unique. But what about the implication in the other direction? I know that uniqueness does not imply Lipschitz continuity. But is there a counterexample? A differential equation that is not L-continuous, still the solution is unique?
I would really like to know the answer to this question.
Thank you all for your help,

Hendrik

2. Sep 9, 2005

### Kajsa_Stina

Now I have found an answer to my question:

[URL]http://archive.numdam.org/ARCHIVE/AFST/
AFST_1996_6_5_4/AFST_1996_6_5_4_577_0/
AFST_1996_6_5_4_577_0.pdf[/url]

or, rather, Bernis and Qwang have found an answer. However, my differential equation is only of first degree, like

\dot K(t) = F(K(t))

One example would be F(K) = K^\alpha with 0 < \alpha < 1, then you get multiple solutions if you start from K = 0. But that's not surprising, because the differential equation is not Lipschitz continuous in K = 0. My question now would be: Is it possible to have a unique solution even if F were L-continuous in 0?

Thanks, many greetings,
Hendrik

Last edited by a moderator: Apr 21, 2017