Abstract:
In this talk we shall discuss a recent paper by T. Kania and G. Lewicki: "A forgotten theorem of Pelczynski: $(\lambda+)$-injective spaces need not be $\lambda$-injective – the case $\lambda \in (1, 2]$". The paper shows that for any $\lambda\in (1,2]$ there exists a $(\lambda+)$-injective Banach space which is not $\lambda$-injective. It is worth noting that for Banach spaces over $\mathbb{R}$ the claim is not true for $\lambda=1$.