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Cited by 1,221

The DOI matches its Crossref record; 1 of the 1 references it cites were found in a registry or an index.

Alternation

Open access
Chandra, Ashok K., Kozen, Dexter C., Stockmeyer, Larry J.·1981·Journal of the ACM

Abstract

Alternation is a generalization of nondeterminism in which existential and universal quantitiers can alternate during the course of a computation, whereas in a nondeterministic computation there are only existential quantifiers.Alternating Turing machines are defined and shown to accept precisely the recursively enumerable sets.Complexity classes of languages accepted by time-(space-) bounded alternating Turing machines are characterized in terms of complexity classes of languages accepted by space-(time-) bounded deterministic Turing machines.In particular, alternating polynomial time is equivalent to deterministic polynomial space and alternating polynomial space is equivalent to deterministic 'exponential time.Subrecursive quantifier hierarchies are defined in terms of time-or space-bounded alternating Tufing machines by bounding the number of alternations allowed during computations.Alternating finite-state automata are defined and shown to accept only regular languages, although, in general, 2 2 states are necessary and sufficient to simulate a k-state alternating finite automaton deterministically.Finally, it is shown that alternating pushdown automata are strictly more powerful than nondeterministic pushdown automata.

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Metadata

Authors
Chandra, A. K., Kozen, D. C., & Stockmeyer, L. J.
Venue
Journal of the ACM
Published
1981-01
Volume
28
Issue
1
Pages
114-133
ISSN
  • 0004-5411 (ISSN-L)
  • 1557-735X
OpenAlex
W4241108585
Cited by
1,221
References
1
FWCI
30.69
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Alternation. https://app.cochat.ai/papers/10.1145/322234.322243
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Chandra, A. K., Kozen, D. C., & Stockmeyer, L. J. (1981). Alternation. Journal of the ACM. https://doi.org/10.1145/322234.322243

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