English
Related papers

Related papers: Two QCMA-complete problems

200 papers

The quantum marginal problem consists in deciding whether a given set of marginal reductions is compatible with the existence of a global quantum state or not. In this work, we formulate the problem from the perspective of dynamical systems…

Quantum Physics · Physics 2022-09-29 Daniel Uzcátegui Contreras , Dardo Goyeneche

Clarifying the relation between the whole and its parts is crucial for many problems in science. In quantum mechanics, this question manifests itself in the quantum marginal problem, which asks whether there is a global pure quantum state…

Quantum Physics · Physics 2021-02-18 Xiao-Dong Yu , Timo Simnacher , Nikolai Wyderka , H. Chau Nguyen , Otfried Gühne

It is demonstrated that quasi-exactly solvable models of quantum mechanics admit an interesting duality transformation which changes the form of their potentials and inverts the sign of all the exactly calculable energy levels. This…

High Energy Physics - Theory · Physics 2007-05-23 A. Krajewska , A. Ushveridze , Z. Walczak

We describe a simple formalism for generating classes of quantum circuits that are classically efficiently simulatable and show that the efficient simulation of Clifford circuits (Gottesman-Knill theorem) and of matchgate circuits…

Quantum Physics · Physics 2008-12-25 Richard Jozsa

In order to establish the computational equivalence between quantum Turing machines (QTMs) and quantum circuit families (QCFs) using Yao's quantum circuit simulation of QTMs, we previously introduced the class of uniform QCFs based on an…

Quantum Physics · Physics 2013-12-18 Harumichi Nishimura , Masanao Ozawa

In complexity theory, there exists a famous unsolved problem whether NP can be P or not. In this paper, we discuss this aspect in SAT (satisfiability) problem, and it is shown that the SAT can be solved in plynomial time by means of quantum…

Quantum Physics · Physics 2008-11-26 Masanori Ohya , Natsuki Masuda

In this paper, we introduce the model of quantum Mealy machines and study the equivalence checking and minimisation problems of them. Two efficient algorithms are developed for checking equivalence of two states in the same machine and for…

Formal Languages and Automata Theory · Computer Science 2022-09-13 Qisheng Wang , Junyi Liu , Mingsheng Ying

In quantum computation every unitary operation can be decomposed into quantum circuits-a series of single-qubit rotations and a single type entangling two-qubit gates, such as controlled-NOT (CNOT) gates. Two measures are important when…

Quantum Physics · Physics 2011-03-07 Martin Plesch , Časlav Brukner

Standard one-way quantum computers (1WQC) combine time symmetric unitary evolution, with asymmetric treatment of boundaries: state preparation allows to enforce a chosen initial state, however, for the final state measurement chooses a…

General Physics · Physics 2023-08-30 Jarek Duda

We prove that QCSP$(\mathbb{N};x=y\rightarrow y=z)$ is PSpace-complete, settling a question open for more than ten years. This completes the complexity classification for the QCSP over equality languages as a trichotomy between Logspace,…

Computational Complexity · Computer Science 2026-05-22 Dmitriy Zhuk , Barnaby Martin , Michal Wrona

We give a simple proof of a formula for the minimal time required to simulate a two-qubit unitary operation using a fixed two-qubit Hamiltonian together with fast local unitaries. We also note that a related lower bound holds for arbitrary…

Quantum Physics · Physics 2007-05-23 Andrew M. Childs , Henry L. Haselgrove , Michael A. Nielsen

Recently, it has been argued that quantum mechanics is a complete theory, and that different quantum states do necessarily correspond to different elements of reality, under the assumptions that quantum mechanics is correct and that…

Quantum Physics · Physics 2015-06-23 Giancarlo Ghirardi , Raffaele Romano

We show that given an explicit description of a multiplayer game, with a classical verifier and a constant number of players, it is QMA-hard, under randomized reductions, to distinguish between the cases when the players have a strategy…

Quantum Physics · Physics 2019-02-12 Anand Natarajan , Thomas Vidick

We describe an efficient approximation algorithm for evaluating the ground-state energy of the classical Ising Hamiltonian with linear terms on an arbitrary planar graph. The running time of the algorithm grows linearly with the number of…

Quantum Physics · Physics 2009-09-16 Nikhil Bansal , Sergey Bravyi , Barbara M. Terhal

Construction of explicit quantum circuits follows the notion of the "standard circuit model" introduced in the solid and profound analysis of elementary gates providing quantum computation. Nevertheless the model is not always optimal (e.g.…

Quantum Physics · Physics 2007-05-23 K. Ch. Chatzisavvas , C. Daskaloyannis , C. P. Panos

Quantum principal component analysis (QPCA) ignited a new development toward quantum machine learning algorithms. Initially showcasing as an active way for analyzing a quantum system using the quantum state itself, QPCA also found potential…

Quantum Physics · Physics 2025-01-15 Nhat A. Nghiem

Quantum hypothesis testing (QHT) provides an effective method to discriminate between two quantum states using a two-outcome positive operator-valued measure (POVM). Two types of decision errors in a QHT can occur. In this paper we focus on…

Quantum Physics · Physics 2023-07-13 Yi Shen , Carlo Maria Scandolo , Lin Chen

Variational quantum algorithms involve training parameterized quantum circuits using a classical co-processor. An important variational algorithm, designed for combinatorial optimization, is the quantum approximate optimization algorithm.…

Tailoring many-body interactions among a proper quantum system endows it with computing ability by means of static quantum computation in the sense that some of the physical degrees of freedom can be used to store binary information and the…

Quantum Physics · Physics 2008-02-03 Haiqing Wei , Xin Xue

We propose a quantum authentication and digital signature protocol whose security is founded on the Quantum Merlin Arthur~(QMA)-completeness of the consistency of local density matrices. The protocol functions as a true public-key…

Quantum Physics · Physics 2025-06-23 Le-Ran Liu , Min-Quan He , Dan-Bo Zhang , Z. D. Wang