I used to work at the University of Helsinki in the Department of Mathematics and Statistics and did some research in the field of set theory.
- Potential isomorphism and semi-proper trees. Joint with Tapani Hyttinen and Saharon Shelah. Fundamenta Mathematicae, 175:127-142, 2002.
- Diamonds on large cardinals. Annales Academiae Scientiarum Fennicae Mathematica Dissertationes, 134, 48 pp., 2003.
- Orders of indescribable sets. Archive for Mathematical Logic, 45:705-714, 2006.
- Saturation of the weakly compact ideal. Proceedings of the American Mathematical Society, 138: 3323-3334, 2010.
- Diamond on the regulars versus weakly compact diamond. In preparation.
URL pointing to this page: http://www.iki.fi/alex.hellsten