*In mathematics you don't understand things. You just get used to them.*

(John von Neumann)

**
Institute of Mathematics
Polish Academy of Sciences
¦niadeckich 8
00-956 Warsaw, Poland
room no. 407**

**Scientific interests:**

- Banach space theory, especially:
- combinatorial methods in Banach spaces
- twisted sums
- vector measures
- generalised bases

- Banach algebras, including:
- operator algebras and their ideals
- C*-algebras, von Neumann algebras

- Functional equations and inequalities, especially:
- Hyers-Ulam stability
- functional equations in number theory