JEDNOSTKA NAUKOWA KATEGORII A+

# Wydawnictwa / Czasopisma IMPAN / Colloquium Mathematicum / Wszystkie zeszyty

## A bifurcation theory for some nonlinear elliptic equations

### Tom 95 / 2003

Colloquium Mathematicum 95 (2003), 139-151 MSC: 35J20, 35B32. DOI: 10.4064/cm95-1-12

#### Streszczenie

We deal with the problem $$\cases {-{\mit\Delta} u= f(x,u)+\lambda g(x,u) & in {\mit\Omega},\cr u_{|\partial {\mit\Omega}}=0,\cr} \tag*{({\rm P}_{\lambda}) }$$ where ${\mit\Omega}\subset {\mathbb R}^n$ is a bounded domain, $\lambda\in {\mathbb R}$, and $f, g:{\mit\Omega}\times {\mathbb R}\to {\mathbb R}$ are two Carathéodory functions with $f(x,0)=g(x,0)=0$. Under suitable assumptions, we prove that there exists $\lambda^{*}>0$ such that, for each $\lambda\in( 0,\lambda^{*})$, problem $( {\rm P}_{\lambda} )$ admits a non-zero, non-negative strong solution $u_{\lambda}\in \bigcap_{p\geq 2}W^{2,p}({\mit\Omega})$ such that $\lim_{\lambda\to 0^+} \|u_{\lambda}\|_{W^{2,p}({\mit\Omega})}=0$ for all $p\geq 2$. Moreover, the function $\lambda\mapsto I_{\lambda}(u_{\lambda})$ is negative and decreasing in $]0,\lambda^{*}[$, where $I_{\lambda}$ is the energy functional related to $({\rm P}_{\lambda})$.

#### Autorzy

• Biagio RicceriDepartment of Mathematics
University of Catania
Viale A. Doria 6
95125 Catania, Italy
e-mail

## Przeszukaj wydawnictwa IMPAN

Zbyt krótkie zapytanie. Wpisz co najmniej 4 znaki.

## Przepisz kod z obrazka Odśwież obrazek