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Related papers: No-go theorems for sublinear-depth group designs

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Babai's conjecture states that, for any finite simple non-abelian group $G$, the diameter of $G$ is bounded by $(\log|G|)^{C}$ for some absolute constant $C$. We prove that, for any untwisted classical group $G$ of rank $r$ defined over a…

Group Theory · Mathematics 2024-12-16 Jitendra Bajpai , Daniele Dona , Harald Andrés Helfgott

Calculating the diameter of an undirected graph requires quadratic running time under the Strong Exponential Time Hypothesis and this barrier works even against any approximation better than 3/2. For planar graphs with positive edge…

Data Structures and Algorithms · Computer Science 2025-07-08 Michał Włodarczyk

Random unitaries are a central object of study in quantum information, with applications to quantum computation, quantum many-body physics, and quantum cryptography. Recent work has constructed unitary designs and pseudorandom unitaries…

Quantum Physics · Physics 2025-09-29 Ben Foxman , Natalie Parham , Francisca Vasconcelos , Henry Yuen

Given a simple graph $G$ and an integer $k$, the goal of $k$-Clique problem is to decide if $G$ contains a complete subgraph of size $k$. We say an algorithm approximates $k$-Clique within a factor $g(k)$ if it can find a clique of size at…

Computational Complexity · Computer Science 2022-08-04 Bingkai Lin , Xuandi Ren , Yican Sun , Xiuhan Wang

We give a strongly explicit construction of $\varepsilon$-approximate $k$-designs for the orthogonal group $\mathrm{O}(N)$ and the unitary group $\mathrm{U}(N)$, for $N=2^n$. Our designs are of cardinality $\mathrm{poly}(N^k/\varepsilon)$…

Computational Complexity · Computer Science 2023-10-23 Ryan O'Donnell , Rocco A. Servedio , Pedro Paredes

For a graph $G$, let $Z(G,\lambda)$ be the partition function of the monomer-dimer system defined by $\sum_k m_k(G)\lambda^k$, where $m_k(G)$ is the number of matchings of size $k$ in $G$. We consider graphs of bounded degree and develop a…

Data Structures and Algorithms · Computer Science 2013-09-05 Marc Lelarge , Hang Zhou

We present a construction for circuits with low gate count and depth, implementing three- and four-body Pauli-Z product operators as they appear in the form of plaquette-shaped constraints in QAOA when using the parity mapping. The circuits…

Quantum Physics · Physics 2024-07-16 Josua Unger , Anette Messinger , Benjamin E. Niehoff , Michael Fellner , Wolfgang Lechner

Let $G$ be an additive group of order $v$. A $k$-element subset $D$ of $G$ is called a $(v, k, \lambda, t)$-almost difference set if the expressions $gh^{-1}$, for $g$ and $h$ in $D$, represent $t$ of the non-identity elements in $G$…

Combinatorics · Mathematics 2014-09-02 Kathleen Nowak

Quantum algorithms for factoring and discrete logarithm have previously been generalized to finding hidden subgroups of finite Abelian groups. This paper explores the possibility of extending this general viewpoint to finding hidden…

Quantum Physics · Physics 2015-06-02 Mark Ettinger , Peter Hoyer

We propose a mechanism for reaching pseudorandom quantum states, computationally indistinguishable from Haar random, with shallow log-n depth quantum circuits, where n is the number of qudits. We argue that $\log n$ depth 2-qubit-gate-based…

Quantum Physics · Physics 2024-04-23 Claudio Chamon , Eduardo R. Mucciolo , Andrei E. Ruckenstein , Zhi-Cheng Yang

Good approximations have been attained for the sparsest cut problem by rounding solutions to convex relaxations via low-distortion metric embeddings. Recently, Bryant and Tupper showed that this approach extends to the hypergraph setting by…

Data Structures and Algorithms · Computer Science 2023-03-09 Adam D. Jozefiak , F. Bruce Shepherd

The architecture of infinite structures with non-crystallographic symmetries can be modeled via aperiodic tilings, but a systematic construction method for finite structures with non-crystallographic symmetry at different radial levels is…

Mathematical Physics · Physics 2015-08-19 Reidun Twarock , Motiejus Valiunas , Emilio Zappa

Let \(G\) be a non-discrete, locally compact group with Haar measure \(m\). We prove that there exists a compact set \(K \subset G\) with \(m(K)=0\) such that \(KK^{-1}\) contains a neighborhood of the identity. Moreover, such a set may be…

Group Theory · Mathematics 2026-03-31 Chuck Akemann

Compiling a high-level quantum circuit down to a low-level description that can be executed on state-of-the-art quantum computers is a crucial part of the software stack for quantum computing. One step in compiling a quantum circuit to some…

Quantum Physics · Physics 2023-04-20 Tom Peham , Lukas Burgholzer , Robert Wille

An upper dominating set is a minimal dominating set in a graph. In the \textsc{Upper Dominating Set} problem, the goal is to find an upper dominating set of maximum size. We study the complexity of parameterized algorithms for \textsc{Upper…

Data Structures and Algorithms · Computer Science 2021-01-20 Louis Dublois , Michael Lampis , Vangelis Th. Paschos

Random quantum states have various applications in quantum information science. We discover a new ensemble of quantum states that serve as an $\epsilon$-approximate state $t$-design while possessing extremely low entanglement, magic, and…

Quantum Physics · Physics 2025-12-25 Wonjun Lee , Minki Hhan , Gil Young Cho , Hyukjoon Kwon

Unitary $k$-designs are probabilistic ensembles of unitary matrices whose first $k$ statistical moments match that of the full unitary group endowed with the Haar measure. In prior work, we showed that the automorphism group of classical…

Quantum Physics · Physics 2021-05-27 Xinyu Tan , Narayanan Rengaswamy , Robert Calderbank

When the gate set has continuous parameters, synthesizing a unitary operator as a quantum circuit is always possible using exact methods, but finding minimal circuits efficiently remains a challenging problem. The landscape is very…

Quantum Physics · Physics 2026-01-07 Janani Gomathi , Alex Meiburg

In the Max-k-diameter problem, we are given a set of points in a metric space, and the goal is to partition the input points into k parts such that the maximum pairwise distance between points in the same part of the partition is minimized.…

Computational Geometry · Computer Science 2024-04-08 Henry Fleischmann , Kyrylo Karlov , Karthik C. S. , Ashwin Padaki , Stepan Zharkov

We introduce the problem of constructing explicit variety evasive subspace families. Given a family $\mathcal{F}$ of subvarieties of a projective or affine space, a collection $\mathcal{H}$ of projective or affine $k$-subspaces is…

Computational Complexity · Computer Science 2024-10-15 Zeyu Guo