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MLQ
2007
91views more  MLQ 2007»
13 years 4 months ago
Almost everywhere domination and superhighness
Let ω denote the set of natural numbers. For functions f, g : ω → ω, we say that f is dominated by g if f(n) < g(n) for all but finitely many n ∈ ω. We consider the st...
Stephen G. Simpson
CORR
1999
Springer
93views Education» more  CORR 1999»
13 years 4 months ago
On the Power of Positive Turing Reductions
: In the early 1980s, Selman's seminal work on positive Turing reductions showed that positive Turing reduction to NP yields no greater computational power than NP itself. Thu...
Edith Hemaspaandra
CORR
2000
Springer
133views Education» more  CORR 2000»
13 years 4 months ago
On Exponential-Time Completeness of the Circularity Problem for Attribute Grammars
Attribute grammars (AGs) are a formal technique for defining semantics of programming languages. Existing complexity proofs on the circularity problem of AGs are based on automata...
Pei-Chi Wu
AML
2004
73views more  AML 2004»
13 years 4 months ago
Finite cupping sets
We show that there exists a single minimal (Turing) degree b < 0 s.t. for all c.e. degrees 0 < a < 0 , 0 = a b. Since b is minimal this means that b complements all c.e....
Andrew Lewis
BSL
2005
70views more  BSL 2005»
13 years 4 months ago
Mass problems and randomness
A mass problem is a set of Turing oracles. If P and Q are mass problems, we say that P is weakly reducible to Q if every member of Q Turing computes a member of P. We say that P i...
Stephen G. Simpson
AMC
2005
94views more  AMC 2005»
13 years 4 months ago
Turing instabilities and patterns near a Hopf bifurcation
We derive a necessary and sufficient condition for Turing instabilities to occur in two-component systems of reaction-diffusion equations with Neumann boundary conditions. We appl...
Rui Dilão
FUIN
2007
120views more  FUIN 2007»
13 years 4 months ago
Concurrent Turing Machines
We define Concurrent Turing Machines (CTMs) as Turing machines with Petri nets as finite control. This leads to machines with arbitrary many tape heads, thus subsuming any class ...
Berndt Farwer, Manfred Kudlek, Heiko Rölke
JAPLL
2008
96views more  JAPLL 2008»
13 years 4 months ago
Simulating Turing machines on Maurer machines
Maurer machines are much closer to real computers than Turing machines. Computer instructions play a prominent part in Maurer machines. We show a straightforward way to simulate Tu...
Jan A. Bergstra, C. A. Middelburg
APAL
2006
123views more  APAL 2006»
13 years 4 months ago
The ibT degrees of computably enumerable sets are not dense
Abstract. We show that the identity bounded Turing degrees of computably enumerable sets are not dense.
George Barmpalias, Andrew E. M. Lewis
APAL
2010
93views more  APAL 2010»
13 years 4 months ago
A measure-theoretic proof of Turing incomparability
We prove that if S is an -model of weak weak K
Chris J. Conidis