Quantum Computing and Quantum Information
- M. Hirvensalo, A. Yakaryılmaz
- Computer Science
- 2019
A quantum algorithm that has a query complexity O(n(logn) √ k) is proposed, which shows speed-up comparing with the deterministic algorithm (radix sort) that requires Ω((n+ d)k) queries, where d is a size of the alphabet.
Undecidability Bounds for Integer Matrices Using Claus Instances
- Vesa Halava, T. Harju, M. Hirvensalo
- MathematicsInternational Journal of Foundations of Computer…
- 1 October 2007
New lower bounds are established in the number of matrices for the mortality, zero in the left upper corner, vector reachability, matrix reachable, scalar reachability and freeness problems and a short proof for a strengthened result due to Bell and Potapov stating that the membership problem is undecidable.
Quantum Automata with Open Time Evolution
- M. Hirvensalo
- Computer Science, PhysicsInternational Journal of Natural Computing…
- 2010
It is shown that the (fuzzy) languages accepted by open evolution quantum automata obey various closure properties, and major other models of finite automata, including probabilistic, measure once quantum, measure many quantum, and Latvian quantum Automata can be simulated by the open quantum evolution automata without increasing the number of the states.
Various Aspects of Finite Quantum Automata
- M. Hirvensalo
- Computer ScienceInternational Conference on Developments in…
- 16 September 2008
Determining the birth date of computer science is a very complicated task and certainly reliant to the standpoint chosen. Some may point out the work of Kurt Godel [18], Alan Turing [31], and Alonso…
Computing with quanta - impacts of quantum theory on computation
- M. Hirvensalo
- Computer ScienceTheoretical Computer Science
- 25 September 2002
Quantum Computing
- M. Hirvensalo
- Computer ScienceNatural Computing Series
- 2001
This second edition of Mika Hirvensalo's quantum computing book differs from most of the previous ones which are mainly physics-oriented because the special style of presentation makes the theory of quantum computing accessible to a larger audience.
Decidability and Undecidability of Marked PCP
- Vesa Halava, M. Hirvensalo, R. D. Wolf
- MathematicsSymposium on Theoretical Aspects of Computer…
- 4 March 1999
The decidability/undecidability-boundary between marked and 2-marked PCP is located, showing that the marked version of the Post Correspondence Problem, where the words on a list are required to differ in the first letter, is decidable.
Improved Undecidability Results on the Emptiness Problem of Probabilistic and Quantum Cut-Point Languages
- M. Hirvensalo
- Computer ScienceConference on Current Trends in Theory and…
- 20 January 2007
We give constructions of small probabilistic and MO-type quantum automata that have undecidable emptiness problem for the cut-point languages.
Positivity of second order linear recurrent sequences
- Vesa Halava, T. Harju, M. Hirvensalo
- MathematicsDiscrete Applied Mathematics
- 1 March 2006
Quantum Computing
- M. Hirvensalo
- Computer ScienceNatural Computing Series
- 2004
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