Scholar iON
Academic Synthesis
This body of research primarily revolves around critical evaluations and corrections of proposed quantum algorithms and methods, with a specific focus on Grover's algorithm and quantum process reconstruction. The papers highlight the importance of rigorous validation within quantum computing, as erroneous claims—such as the purported exponential speedup of the Grover algorithm—can mislead advancements in computer science and quantum information theory. Additionally, the discourse includes the refinement of criteria for quantum entanglement, underscoring the necessity for accurate theoretical frameworks in quantum mechanics. Collectively, these critiques contribute to the ongoing dialogue and development of foundational quantum principles, ensuring that advancements are based on scientifically sound methodologies.
In a recent paper (quant-ph/0506105), A S Gupta, M. Gupta and A. Pathak proposed a modified Grover algorithm that would exponentially accelerate the unsorted database search problem if the number of marked items is known. If this were true, it would represent a major fundamental breakthrough in computer science, mathematics, quantum information and other related branches of sciences.
However the algorithm is not valid. We will explain it in this brief comment.
In this note, we show the mistake which has been made in quant-ph/0609176. Further more, we provide a sketch of proof to show the impossibility of the effort of such kind toward improving the efficiency of Grover's Algorithm.
The treatment proposed by Sacchi quant-ph/0009104 does not represent correct solution, since the necessary conditions on CP maps are not guaranteed.
In quant-ph/0205017 v1 Chen, Wu and Yang formulated a necessary separability criterion based on a realignment method for matrices. This note is to point out that this criterion is identical to the necessary cross norm criterion previously put forward by this author.
We show that arguments in the comment by Schwab et al. quant-ph/0503018 on our recent work are invalid.
We show that Bell correlations may arise as a special sort of selection artefact, produced by ordinary control of the initial state of the experiments concerned. This accounts for nonlocality, without recourse to any direct spacelike causality or influence. The argument improves an earlier proposal in (arXiv:2101.05370v4 [quant-ph], arXiv:2212.06986 [quant-ph]) in two main respects: (i) in demonstrating its application in a real Bell experiment; and (ii) in avoiding the need for a postulate of retrocausality. This version includes an Appendix, discussing the relation of the proposal to the conclusions of Wood and Spekkens (arXiv:1208.4119 [quant-ph]).
This paper has been superseded by quant-ph/0101003.
We withdraw this paper due to insufficient arguments in the derivation of Theorem 1. See quant-ph/0005062 for the new paper
This paper is withdrawn as it is equivalent to the paper quant-ph/9605035 by Gilles Brassard.
Withdrawn; replaced by longer, more detailed paper quant-ph/0010065.