20 Citations
Separating the Lower Levels of the Sublogarithmic Space Hierarchy
- MathematicsSTACS
- 1993
It is shown that for each S between loglogn and logn, Σ2SPACE(S) and Σ3SPACE (S) are not closed under complement, which implies the hierarchy Σ1SPACE(-1,2,3) ⊂Σ2 SPACE(-3,4) and the power of weak and strong sublogarithmic space bounded ATMs is compared.
The Sublogarithmic Alternating Space World
- MathematicsSIAM J. Comput.
- 1995
This paper tries to fully characterize the properties and relationships of space classes defined by Turing machines that use less than logarithmic space -- may they be deterministic, nondeterministic…
SIGACT News Complexity Theory Column 10
- Computer ScienceSIGA
- 1995
This work presents recent advances on space-efficient deterministic simulation of probabilistic automata in both finite-state automata and logarithmic-space-bounded Turing machines.
The Separation of NP and PSPACE
- Computer ScienceArXiv
- 2021
This paper shows that NP 6= PSPACE via the premise of NTIME[S(n)] ⊆ DSPACE[S (n)], and then by diagonalization over all polynomial-time nondeterministic Turing machines via universal nondetergetic Turing machine M0 running in O(n ) space for any k ∈ N1.
Some Accepting Powers of Three-Dimensional Synchronized Alternating Turing Machines
- Business
- 2007
This paper introduces a three-dimensional synchronized alternating Turing machine (3-SATM), and investigates fundamental properties of 3-SATM ′s whose input tapes are restricted to cubic ones. The…
Some Accepting Powers of Three-Dimensional Synchronized Alternating Turing Machines
- Business
- 2007
This paper introduces a three-dimensional synchronized alternating Turing machine (3-SATM), and investigates fundamental properties of 3-SATM 0 s whose input tapes are restricted to cubic ones. The…
Guest Column: One-Tape Turing Machine Variants and Language Recognition
- Computer ScienceSIGA
- 2015
Two restricted versions of one-tape Turing machines are presented and for d = 2 deterministic limited automata are equivalent to deterministic pushdown automata, namely they characterize deterministic context-free languages.
Restricted Turing Machines and Language Recognition
- Computer ScienceLATA
- 2016
In 1965 Hennie proved that one-tape deterministic Turing machines working in linear time are equivalent to finite automata, namely they characterize regular languages, and in 1967 Hibbard proved that for each integer \(d\ge 2\), one-Tape Turing machines that are allowed to rewrite each tape cell only in the first d visits are equivalents to pushdown automata.
Nondeterministic One-Tape Off-Line Turing Machines and Their Time Complexity
- Computer ScienceJ. Autom. Lang. Comb.
- 2009
This paper shows that the running time of each nondeterministic machine accepting a nonregular language must grow at least as n log n, and proves that under this measure, each accepting computation should exhibit a crossing sequence of length at least log log n.
Resolution of The Linear-Bounded Automata Question
- Computer ScienceArXiv
- 2021
This work resolve a longstanding open question in automata theory, i.e. the linear-bounded automata question ( shortly, LBA question), which can also be phrased succinctly in the language of…
References
SHOWING 1-10 OF 83 REFERENCES
On Non- uniform Polynomial Space
- MathematicsComputational Complexity Conference
- 1986
Some properties of a dual class defined by exponential lower bounds are shown, as a version of Lupanov theorem and a characterization in terms of oracle Turing machines.
Limitations on Separating Nondeterministic Complexity Classes
- Computer ScienceSIAM J. Comput.
- 1981
If the time bounds defining two nondeterministic complexity classes are too close for separation by the two known techniques, then they are almost too close to separation by any relativizable technique, implying $\operatorname{NSPACE}(\log n) = \operatORName{DSPACE})$.
Space Bounded Computations: Review and New Separation Results
- Computer ScienceTheor. Comput. Sci.
- 1991
Languages that Capture Complexity Classes
- Computer Science, MathematicsSIAM J. Comput.
- 1987
It is shown that projection translations are a uniform version of Valiant’s projections, and that the usual complete problems remain complete via these very restrictive reductions.
Some connections between nonuniform and uniform complexity classes
- Mathematics, Computer ScienceSTOC '80
- 1980
This work aims to understand when nonuniform upper bounds can be used to obtain uniform upper bounds, and how to relate it to more common notions.
On some "non-uniform" complexity measures
- Computer ScienceFCT
- 1985
The initial index of languages is introduced by means of several computational models and is shown to be closely related to context-free cost, boolean circuits, straight line programs, and Turing machines with sparse oracles and time or space bounds.
Some Results on Tape-Bounded Turing Machines
- Computer ScienceJACM
- 1969
It is shown that the lower bounds on tape complexity of [1] depend on neither the halting assumption nor determinism, and that below log n tape complexity there exists a dense hierarchy of complexity classes for two-way nondeterministic devices.
Space-Bounded Hierarchies and Probabilistic Computations
- Computer ScienceJ. Comput. Syst. Sci.
- 1984