Sign-changing multi-bubble solutions for the Brezis-Nirenberg problem in four dimensions

Angela Pistoia, Giuseppe Mario Rago, Giusi Vaira

We construct families of sign-changing solutions for the four-dimensional Brezis--Nirenberg problem \[ -Δu=u^3+\varepsilon u\quad\text{in }Ω,\qquad u=0\quad\text{on }\partialΩ, \]…