papers

Publications (37)

cs.DS2024

Faster Approximation Algorithms for Restricted Shortest Paths in Directed Graphs

Vikrant Ashvinkumar, Aaron Bernstein, Adam Karczmarz

In the restricted shortest paths problem, we are given a graph whose edges are assigned two non-negative weights: lengths and delays, a source , and a delay threshold . T…

cs.DS2024

Closing the Gap Between Directed Hopsets and Shortcut Sets

Aaron Bernstein, Nicole Wein

For an n-vertex directed graph , a -\emph{shortcut set} is a set of additional edges such that has the same transitive closur…

cs.DS2020

Fully-Dynamic Graph Sparsifiers Against an Adaptive Adversary

Aaron Bernstein, Jan van den Brand, Maximilian Probst Gutenberg +4

Designing dynamic graph algorithms against an adaptive adversary is a major goal in the field of dynamic graph algorithms. While a few such algorithms are known for spanning trees,…

cs.DS2018

Towards a Unified Theory of Sparsification for Matching Problems

Sepehr Assadi, Aaron Bernstein

In this paper, we present a construction of a `matching sparsifier', that is, a sparse subgraph of the given graph that preserves large matchings approximately and is robust to mod…

physics.plasm-ph2019

Observation of Plasma Bubble Structures in a GeV Laser-Plasma Accelerator

Yen-Yu Chang, Kathleen Weichman, Xiantao Cheng +8

We measure characteristics of plasma bubbles in GeV-class laser-plasma accelerators (LPAs) using Faraday rotation diagnostics. We extend these techniques, previously demonstrated f…

cs.DS2025

Separations between Oblivious and Adaptive Adversaries for Natural Dynamic Graph Problems

Aaron Bernstein, Sayan Bhattacharya, Nick Fischer +2

We establish the first update-time separation between dynamic algorithms against oblivious adversaries and those against adaptive adversaries in natural dynamic graph problems, bas…

cs.DS2025

Combinatorial Maximum Flow via Weighted Push-Relabel on Shortcut Graphs

Aaron Bernstein, Joakim Blikstad, Jason Li +2

We give a combinatorial algorithm for computing exact maximum flows in directed graphs with vertices and edge capacities from in time,…

cs.DS2025

Maximum Flow by Augmenting Paths in Time

Aaron Bernstein, Joakim Blikstad, Thatchaphol Saranurak +1

We present a combinatorial algorithm for computing exact maximum flows in directed graphs with vertices and edge capacities from in time, whi…

cs.DC2024

Parallel, Distributed, and Quantum Exact Single-Source Shortest Paths with Negative Edge Weights

Vikrant Ashvinkumar, Aaron Bernstein, Nairen Cao +5

This paper presents parallel, distributed and quantum algorithms for single-source shortest paths when edges can have negative weights (negative-weight SSSP). We show a framework t…

cs.DS2023

All-Norm Load Balancing in Graph Streams via the Multiplicative Weights Update Method

Sepehr Assadi, Aaron Bernstein, Zachary Langley

In the weighted load balancing problem, the input is an -vertex bipartite graph between a set of clients and a set of servers, and each client comes with some nonnegative real w…

cs.DS2017

Deterministic Partially Dynamic Single Source Shortest Paths in Weighted Graphs

Aaron Bernstein

In this paper we consider the decremental single-source shortest paths (SSSP) problem, where given a graph and a source node the goal is to maintain shortest distances betw…

cs.DM2018

General Bounds for Incremental Maximization

Aaron Bernstein, Yann Disser, Martin Groß

We propose a theoretical framework to capture incremental solutions to cardinality constrained maximization problems. The defining characteristic of our framework is that the cardi…

cs.DS2018

Online Bipartite Matching with Amortized Replacements

Aaron Bernstein, Jacob Holm, Eva Rotenberg

In the online bipartite matching problem with replacements, all the vertices on one side of the bipartition are given, and the vertices on the other side arrive one by one with all…

cs.DS2021

Deterministic Decremental Reachability, SCC, and Shortest Paths via Directed Expanders and Congestion Balancing

Aaron Bernstein, Maximilian Probst Gutenberg, Thatchaphol Saranurak

Let be a weighted, digraph subject to a sequence of adversarial edge deletions. In the decremental single-source reachability problem (SSR), we are given a fixed sour…

cs.DS2015

Fully Dynamic Matching in Bipartite Graphs

Aaron Bernstein, Cliff Stein

Maximum cardinality matching in bipartite graphs is an important and well-studied problem. The fully dynamic version, in which edges are inserted and deleted over time has also bee…

cs.DS2020

Near-Optimal Decremental SSSP in Dense Weighted Digraphs

Aaron Bernstein, Maximilian Probst Gutenberg, Christian Wulff-Nilsen

In the decremental Single-Source Shortest Path problem (SSSP), we are given a weighted directed graph undergoing edge deletions and a source vertex ; let $n =…

cs.DS2025

Reviving Thorup's Shortcut Conjecture

Aaron Bernstein, Henry Fleischmann, Maximilian Probst Gutenberg +7

We aim to revive Thorup's conjecture [Thorup, WG'92] on the existence of reachability shortcuts with ideal size-diameter tradeoffs. Thorup originally asked whether, given any graph…

cs.DS2025

Are there graphs whose shortest path structure requires large edge weights?

Aaron Bernstein, Greg Bodwin, Nicole Wein

The aspect ratio of a (positively) weighted graph is the ratio of its maximum edge weight to its minimum edge weight. Aspect ratio commonly arises as a complexity measure in gr…

cs.DS2026

Parallel Reachability and Shortest Paths on Non-sparse Digraphs: Near-linear Work and Sub-square-root Depth

Vikrant Ashvinkumar, Aaron Bernstein, Maximilian Probst Gutenberg +1

We present parallel algorithms for computing single-source reachability and shortest paths on directed -vertex -edge graphs using near-linear work and $o(\sqrt…

cs.DS2022

Decremental Matching in General Graphs

Sepehr Assadi, Aaron Bernstein, Aditi Dudeja

We consider the problem of maintaining an approximate maximum integral matching in a dynamic graph , while the adversary makes changes to the edges of the graph. The goal is to…

cs.DS2019

Distance-preserving graph contractions

Aaron Bernstein, Karl Däubel, Yann Disser +3

Compression and sparsification algorithms are frequently applied in a preprocessing step before analyzing or optimizing large networks/graphs. In this paper we propose and study a…

cs.DS2024

Low Sensitivity Hopsets

Vikrant Ashvinkumar, Aaron Bernstein, Chengyuan Deng +2

Given a weighted graph , a -hopset is an edge set such that for any , where can reach in , there is a path from to in $G \…

cs.DS2021

A Deamortization Approach for Dynamic Spanner and Dynamic Maximal Matching

Aaron Bernstein, Sebastian Forster, Monika Henzinger

Many dynamic graph algorithms have an amortized update time, rather than a stronger worst-case guarantee. But amortized data structures are not suitable for real-time systems, wher…

cs.DS2025

Deterministic Dynamic Maximal Matching in Sublinear Update Time

Aaron Bernstein, Sayan Bhattacharya, Peter Kiss +1

We give a fully dynamic deterministic algorithm for maintaining a maximal matching of an -vertex graph in amortized update time. This breaks the long-standi…

cs.DS2021

Deterministic Decremental SSSP and Approximate Min-Cost Flow in Almost-Linear Time

Aaron Bernstein, Maximilian Probst Gutenberg, Thatchaphol Saranurak

In the decremental single-source shortest paths problem, the goal is to maintain distances from a fixed source to every vertex in an -edge graph undergoing edge deletion…

cs.DS2026

Distributed Load Balancing on Unrelated Machines

Aaron Bernstein, Anupam Gupta, Zhaozi Wang

We study the well-known load balancing problem in the distributed CONGEST model of computation. We consider the unrelated machines setting, where each job specifies a size $s_{…

cs.DC2020

Improved Bounds for Distributed Load Balancing

Sepehr Assadi, Aaron Bernstein, Zachary Langley

In the load balancing problem, the input is an -vertex bipartite graph and a positive weight for each client . The algorithm must assign each client…

physics.optics2019

Time-Resolved Pulse Propagation in Glass in Single-Shot

Yen-Yu Chang, Zhengyan Li, James Welch +3

We report time-resolved pulse self-steepening and temporal splitting in flint glass (SF11) in single-shot using broadband frequency-domain streak camera (B-FDSC). The broadband ($6…

cs.DS2024

Streaming and Communication Complexity of Load-Balancing via Matching Contractors

Sepehr Assadi, Aaron Bernstein, Zachary Langley +2

In the load-balancing problem, we have an -vertex bipartite graph between a set of clients and servers. The goal is to find an assignment of all clients to the ser…

cs.DS2019

Decremental Strongly-Connected Components and Single-Source Reachability in Near-Linear Time

Aaron Bernstein, Maximilian Probst, Christian Wulff-Nilsen

Computing the Strongly-Connected Components (SCCs) in a graph is known to take only time using an algorithm by Tarjan from 1972[SICOMP 72] where , $n=…

cs.DS2026

Bounding the Fragmentation of B-Trees Subject to Batched Insertions

Michael A. Bender, Aaron Bernstein, Nairen Cao +5

The issue of internal fragmentation in data structures is a fundamental challenge in database design. A seminal result of Yao in this field shows that evenly splitting the leaves o…

cs.DC2019

Distributed Exact Weighted All-Pairs Shortest Paths in Near-Linear Time

Aaron Bernstein, Danupon Nanongkai

In the {\em distributed all-pairs shortest paths} problem (APSP), every node in the weighted undirected distributed network (the CONGEST model) needs to know the distance from ever…

cs.DS2020

Improved Bound for Matching in Random-Order Streams

Aaron Bernstein

We study the problem of computing an approximate maximum cardinality matching in the semi-streaming model when edges arrive in a \emph{random} order. In the semi-streaming model, t…

cs.DS2025

Negative-Weight Single-Source Shortest Paths in Near-linear Time

Aaron Bernstein, Danupon Nanongkai, Christian Wulff-Nilsen

We present a randomized algorithm that computes single-source shortest paths (SSSP) in time when edge weights are integral and can be negative. This essential…

cs.DS2024

Matching Composition and Efficient Weight Reduction in Dynamic Matching

Aaron Bernstein, Jiale Chen, Aditi Dudeja +3

We consider the foundational problem of maintaining a -approximate maximum weight matching (MWM) in an -node dynamic graph undergoing edge insertions and deleti…

cs.DS2025

From Unweighted to Weighted Dynamic Matching in Non-Bipartite Graphs: A Low-Loss Reduction

Aaron Bernstein, Jiale Chen

We study the approximate maximum weight matching (MWM) problem in a fully dynamic graph subject to edge insertions and deletions. We design meta-algorithms that reduce the problem…

cs.DS2018

Coresets Meet EDCS: Algorithms for Matching and Vertex Cover on Massive Graphs

Sepehr Assadi, MohammadHossein Bateni, Aaron Bernstein +2

As massive graphs become more prevalent, there is a rapidly growing need for scalable algorithms that solve classical graph problems, such as maximum matching and minimum vertex co…