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Laszlo Pyber

Publications and source records attributed to Laszlo Pyber.

2 recordsLinked to original sources

Finitely generated groups with polynomial index growth

We prove that a finitely generated soluble residually finite group has polynomial index growth if and only if it is a minimax group. We also show that if a finitely generated group with PIG is residually finite-soluble then it is a linear group. These results apply in particular to boundedly generated groups; they imply that every infinite BG residually finite group has an infinite linear quotient.

math.GR

Permutation groups, minimal degrees and quantum computing

We study permutation groups of given minimal degree without the classical primitivity assumption. We provide sharp upper bounds on the order of a permutation group of minimal degree m and on the number of its elements of any given support. These results contribute to the foundations of a non-commutative coding theory. A main application of our results concerns the Hidden Subgroup Problem for the symmetric group in Quantum Computing. We completely characterize the hidden subgroups of the symmetric group that can be distinguished from identity with weak Quantum Fourier Sampling, showing these are exactly the subgroups with bounded minimal degree. This implies that the weak standard method for the symmetric group has no advantage whatsoever over classical exhaustive search.

quant-ph