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Title: Reachability in Deletion-Only Chemical Reaction Networks
For general discrete Chemical Reaction Networks (CRNs), the fundamental problem of reachability - the question of whether a target configuration can be produced from a given initial configuration - was recently shown to be Ackermann-complete. However, many open questions remain about which features of the CRN model drive this complexity. We study a restricted class of CRNs with void rules, reactions that only decrease species counts. We further examine this regime in the motivated model of step CRNs, which allow additional species to be introduced in discrete stages. With and without steps, we characterize the complexity of the reachability problem for CRNs with void rules. We show that, without steps, reachability remains polynomial-time solvable for bimolecular systems but becomes NP-complete for larger reactions. Conversely, with just a single step, reachability becomes NP-complete even for bimolecular systems. Our results provide a nearly complete classification of void-rule reachability problems into tractable and intractable cases, with only a single exception.  more » « less
Award ID(s):
2329918
PAR ID:
10657115
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Editor(s):
Schaeffer, Josie; Zhang, Fei
Publisher / Repository:
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Date Published:
Volume:
347
ISSN:
1868-8969
Page Range / eLocation ID:
3:1-3:21
Subject(s) / Keyword(s):
CRN Chemical Reaction Network Reachability Void Reactions Theory of computation → Models of computation Theory of computation → Problems, reductions and completeness
Format(s):
Medium: X Size: 21 pages; 981146 bytes Other: application/pdf
Size(s):
21 pages 981146 bytes
Sponsoring Org:
National Science Foundation
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