What's Up with Downward Collapse: Using the Easy-Hard Technique to Link Boolean and Polynomial Hierarchy Collapses
| dc.creator | Hemaspaandra, Edith | |
| dc.creator | Hemaspaandra, Lane A. | |
| dc.creator | Hempel, Harald | |
| dc.date | 1999-10-01 | |
| dc.date.accessioned | 2026-07-25T16:57:25Z | |
| dc.description | During the past decade, nine papers have obtained increasingly strong consequences from the assumption that boolean or bounded-query hierarchies collapse. The final four papers of this nine-paper progression actually achieve downward collapse---that is, they show that high-level collapses induce collapses at (what beforehand were thought to be) lower complexity levels. For example, for each $k\geq 2$ it is now known that if $\psigkone=\psigktwo$ then $\ph=\sigmak$. This article surveys the history, the results, and the technique---the so-called easy-hard method---of these nine papers. | |
| dc.description | 37 pages. an extended abstract appeared in SIGACT News, 29, 10-22, 1998 | |
| dc.identifier | https://arxiv.org/abs/cs/9910002 | |
| dc.identifier | http://arxiv.org/abs/cs/9910002 | |
| dc.identifier.uri | https://dspace.dare.co.zw/handle/123456789/44503 | |
| dc.subject | Computational Complexity | |
| dc.subject | F.1.3 | |
| dc.title | What's Up with Downward Collapse: Using the Easy-Hard Technique to Link Boolean and Polynomial Hierarchy Collapses | |
| dc.type | text |