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Related papers: (No) Quantum space-time tradeoff for USTCON

200 papers

In a recent breakthrough, Charalampopoulos, Gawrychowski, Mozes, and Weimann (STOC 2019) showed that exact distance queries on planar graphs could be answered in $n^{o(1)}$ time by a data structure occupying $n^{1+o(1)}$ space, i.e., up to…

Data Structures and Algorithms · Computer Science 2020-07-20 Yaowei Long , Seth Pettie

We present a low-energy deterministic distributed algorithm that computes exact Single-Source Shortest Paths (SSSP) in near-optimal time: it runs in $\tilde{O}(n)$ rounds and each node is awake during only $poly(\log n)$ rounds. When a node…

Data Structures and Algorithms · Computer Science 2024-09-25 Mohsen Ghaffari , Anton Trygub

We present a quantum algorithm for portfolio optimization. We discuss the market data input, the processing of such data via quantum operations, and the output of financially relevant results. Given quantum access to the historical record…

Quantum Physics · Physics 2018-11-12 Patrick Rebentrost , Seth Lloyd

We give optimally fast $O(\log p)$ time (per processor) algorithms for computing round-optimal broadcast schedules for message-passing parallel computing systems. This affirmatively answers the questions posed in Tr\"aff (2022). The problem…

Distributed, Parallel, and Cluster Computing · Computer Science 2024-04-03 Jesper Larsson Träff

We offer an alternative to the conventional network formulation of quantum computing. We advance the analog approach to quantum logic gate/circuit construction. As an illustration, we consider the spatially extended NOT gate as the first…

Quantum Physics · Physics 2014-11-18 Dima Mozyrsky , Vladimir Privman , Steven P. Hotaling

We present a number of new physical systems that may be addressed using methods of time dependent transformation. A recap of results available for two-state systems is given, with particular emphasis on the AC stark effect. We give some…

Quantum Physics · Physics 2023-06-05 Peter Morrison

Given $n$ wireless transceivers located in a plane, a fundamental problem in wireless communications is to construct a strongly connected digraph on them such that the constituent links can be scheduled in fewest possible time slots,…

Data Structures and Algorithms · Computer Science 2012-03-15 Magnus M. Halldorsson , Pradipta Mitra

We define a class of stochastic processes based on evolutions and measurements of quantum systems, and consider the complexity of predicting their long-term behavior. It is shown that a very general class of decision problems regarding…

Computational Complexity · Computer Science 2007-05-23 John Watrous

The operation of a quantum heat engine in finite time generally faces a trade-off between efficiency and power. Using shortcuts to adiabaticity (STA), this trade off can be avoided to engineer thermal machines that operate at maximum…

Quantum Physics · Physics 2019-05-01 Adolfo del Campo , Aurélia Chenu , Shujin Deng , Haibin Wu

We study the Unitary Hitting Time Problem (UHTP) in quantum dynamics. Given computably described pure states |a>, |b> and a time-dependent unitary U(t), define the hitting time as the infimum of t > 0 such that the fidelity between U(t)|a>…

Quantum Physics · Physics 2026-04-13 Katsufumi Matsuura

Using a thermodynamically consistent, mesoscopic model for modern complementary metal-oxide-semiconductor transistors, we study an array of logical circuits and explore how their function is constrained by recent thermodynamic uncertainty…

Statistical Mechanics · Physics 2025-03-28 Phillip Helms , Songela W. Chen , David T. Limmer

In the typical model, a discrete-time coined quantum walk searching the 2D grid for a marked vertex achieves a success probability of $O(1/\log N)$ in $O(\sqrt{N \log N})$ steps, which with amplitude amplification yields an overall runtime…

Quantum Physics · Physics 2018-02-15 Thomas G. Wong

We study the shared processor scheduling problem with a single shared processor where a unit time saving (weight) obtained by processing a job on the shared processor depends on the job. A polynomial-time optimization algorithm has been…

Discrete Mathematics · Computer Science 2021-01-19 Dariusz Dereniowski , Wieslaw Kubiak

We show that all languages accepted in time f(n) >= n^2 can be accepted in space O(f(n)^{1/2})_and_ in time O(f(n)). The proof is carried out by simulation, based on the idea of guessing the sequences of internal states of the simulated TM…

Computational Complexity · Computer Science 2010-01-27 Nicola Caporaso

The spatial search problem consists in minimizing the number of steps required to find a given site in a network, under the restriction that only oracle queries or translations to neighboring sites are allowed. In this paper, a quantum…

Quantum Physics · Physics 2012-05-18 G. Abal , R. Donangelo , F. L. Marquezino , R. Portugal

In this paper, we study the landscape of an online nonconvex optimization problem, for which the input data vary over time and the solution is a trajectory rather than a single point. To understand the complexity of finding a global…

Optimization and Control · Mathematics 2020-11-03 S. Fattahi , C. Josz , Y. Ding , R. Mohammadi , J. Lavaei , S. Sojoudi

Precise time synchronisation underpins critical infrastructure from telecommunications and financial markets to power grids and scientific metrology. Several families of quantum protocols have been proposed and demonstrated for clock…

Quantum Physics · Physics 2026-04-14 Michal Krelina , Utku Tefek , Zeki C. Seskir , Kadir Durak

We address the problem of energy-error tradeoff in the discrimination between two linear passive quantum optical devices with a single use. We provide an analytical derivation of the optimal strategy for beamsplitters and an iterative…

Quantum Physics · Physics 2015-05-27 Alessandro Bisio , Michele Dall'Arno , Giacomo Mauro D'Ariano

We introduce space-efficient plane-sweep algorithms for basic planar geometric problems. It is assumed that the input is in a read-only array of $n$ items and that the available workspace is $\Theta(s)$ bits, where $\lg n \leq s \leq n…

Data Structures and Algorithms · Computer Science 2016-04-25 Amr Elmasry , Frank Kammer

We give a deterministic $O(m\log^{2/3}n)$-time algorithm for single-source shortest paths (SSSP) on directed graphs with real non-negative edge weights in the comparison-addition model. This is the first result to break the $O(m+n\log n)$…

Data Structures and Algorithms · Computer Science 2025-07-31 Ran Duan , Jiayi Mao , Xiao Mao , Xinkai Shu , Longhui Yin