Speaker

# Giovanni Solda

Ghent University

### Talks at this conference:

Wednesday, 15:40, J431 |
## Better quasi-orders and iterated ideals |

The notion of better quasi-order (henceforth bqo) is a natural evolution of that of well quasi-order (henceforth wqo). Intuitively, a wqo is bqo if all of its iterated powersets are also wqo’s: this gives bqo’s much stronger closure properties than the ones wqo’s enjoy. In this talk, we give a new characterization of bqo’s.
Inspired by the intuition we gave above, we look
at the class of |