309 citations · 918 across the 20 of their papers we have counts for
20 papers
Iterative Quantum Algorithms for Maximum Independent Set: A Tale of Low-Depth Quantum Algorithms
Lucas T. Brady, Stuart Hadfield
Quantum algorithms have been widely studied in the context of combinatorial optimization problems. While this endeavor can often analytically and practically achieve quadratic spee…
Switching Time Optimization for Binary Quantum Optimal Control
Xinyu Fei, Lucas T. Brady, Jeffrey Larson +2
Quantum optimal control is a technique for controlling the evolution of a quantum system and has been applied to a wide range of problems in quantum physics. We study a binary quan…
Quantum Adversarial Learning in Emulation of Monte-Carlo Methods for Max-cut Approximation: QAOA is not optimal
Cem M. Unsal, Lucas T. Brady
One of the leading candidates for near-term quantum advantage is the class of Variational Quantum Algorithms, but these algorithms suffer from classical difficulty in optimizing th…
Lower Bounds on Quantum Annealing Times
Luis Pedro García-Pintos, Lucas T. Brady, Jacob Bringewatt +1
The adiabatic theorem provides sufficient conditions for the time needed to prepare a target ground state. While it is possible to prepare a target state much faster with more gene…
Binary Control Pulse Optimization for Quantum Systems
Xinyu Fei, Lucas T. Brady, Jeffrey Larson +2
Quantum control aims to manipulate quantum systems toward specific quantum states or desired operations. Designing highly accurate and effective control steps is vitally important…
Simultaneous Stoquasticity
Jacob Bringewatt, Lucas T. Brady
Stoquastic Hamiltonians play a role in the computational complexity of the local Hamiltonian problem as well as the study of classical simulability. In particular, stoquastic Hamil…
Lefschetz Thimble Quantum Monte Carlo for Spin Systems
T. C. Mooney, Jacob Bringewatt, Neill C. Warrington +1
Monte Carlo simulations are useful tools for modeling quantum systems, but in some cases they suffer from a sign problem, leading to an exponential slow down in their convergence t…
Behavior of Analog Quantum Algorithms
Lucas T. Brady, Lucas Kocia, Przemyslaw Bienias +3
Analog quantum algorithms are formulated in terms of Hamiltonians rather than unitary gates and include quantum adiabatic computing, quantum annealing, and the quantum approximate…
Optimal Protocols in Quantum Annealing and QAOA Problems
Lucas T. Brady, Christopher L. Baldwin, Aniruddha Bapat +2
Quantum Annealing (QA) and the Quantum Approximate Optimization Algorithm (QAOA) are two special cases of the following control problem: apply a combination of two Hamiltonians to…
Quantum Approximate Optimization of the Long-Range Ising Model with a Trapped-Ion Quantum Simulator
G. Pagano, A. Bapat, P. Becker +13
Quantum computers and simulators may offer significant advantages over their classical counterparts, providing insights into quantum many-body systems and possibly improving perfor…
Evolution-Time Dependence in Near-Adiabatic Quantum Evolutions
Lucas Brady, Wim van Dam
We expand upon the standard quantum adiabatic theorem, examining the time-dependence of quantum evolution in the near-adiabatic limit. We examine a Hamiltonian that evolves along s…
Necessary Adiabatic Run Times in Quantum Optimization
Lucas T. Brady, Wim van Dam
Quantum annealing is guaranteed to find the ground state of optimization problems in the adiabatic limit. Recent work [Phys. Rev. X 6, 031010 (2016)] has found that for some barrie…
Discrepancies between Asymptotic and Exact Spectral Gap Analyses of Quantum Adiabatic Barrier Tunneling
Lucas T. Brady, Wim van Dam
We study the asymptotic behavior of the spectral gap of simple barrier tunneling problems, which are related to using quantum annealing to find the global optimum of cost functions…
Constraints on large- parton distributions from new weak boson production and deep-inelastic scattering data
A. Accardi, L. T. Brady, W. Melnitchouk +2
We present a new set of leading twist parton distribution functions, referred to as "CJ15", which take advantage of developments in the theoretical treatment of nuclear corrections…
Spectral Gap Analysis for Efficient Tunneling in Quantum Adiabatic Optimization
Lucas T. Brady, Wim van Dam
We investigate the efficiency of Quantum Adiabatic Optimization when overcoming potential barriers to get from a local to a global minimum. Specifically we look at n qubit systems…
Quantum Monte Carlo Simulations of Tunneling in Quantum Adiabatic Optimization
Lucas T. Brady, Wim van Dam
We explore to what extent path-integral quantum Monte Carlo methods can efficiently simulate the tunneling behavior of quantum adiabatic optimization algorithms. Specifically we lo…
Nuclear effects in the proton-deuteron Drell-Yan process
P. J. Ehlers, A. Accardi, L. T. Brady +1
We compute the nuclear corrections to the proton-deuteron Drell-Yan cross section for inclusive dilepton production, which, when combined with the proton-proton cross section, is u…
Scrambling with Matrix Black Holes
Lucas Brady, Vatche Sahakian
If black holes are not to be dreaded syncs of information but be fully described by unitary evolution, they must scramble in-falling data and eventually leak it through Hawking rad…
Impact of PDF uncertainties at large x on heavy boson production
L. T. Brady, A. Accardi, W. Melnitchouk +1
We explore the sensitivity of W and Z boson production in hadronic collisions to uncertainties in parton distribution functions (PDFs) at large x arising from uncertainties in nucl…
Next-to leading order analysis of target mass corrections to structure functions and asymmetries
L. T. Brady, A. Accardi, T. J. Hobbs +1
We perform a comprehensive analysis of target mass corrections (TMCs) to spin-averaged structure functions and asymmetries at next-to-leading order. Several different prescriptions…