Questions tagged [algorithms]
For questions about an algorithm as it relates to physics. DO NOT ask how to implement an algorithm, questions like that belong on Stack Overflow or Computational Science. DO NOT ask about the efficiency of an algorithm, or other such questions, questions like that belong on Computational Science.
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Why use the QR factorization method to diagonalize a matrix? Considering better alternatives
Last year, I took a course in Computational Physics, where I learnt methods to integrate and differentiate functions, diagonalize matrices, etc. More precisely, I recall we would diagonalize matrices ...
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References for Numerical Solutions of the Feynman Path Integral
I am looking for references that discuss numerical approaches to evaluating the Feynman path integral.
Specifically, I would like references (books, papers, or reviews) that cover:
Discretization ...
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Doubt in Verlet's Algorithm
In studying the temporal evolution of a system according to the deterministic model, we begin by considering a Taylor series expansion for the displacement $r$. First, we consider a positive variation ...
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Go a step further and get the both results of $f(x)$ in Deutsch algorithm
The Deutsch-Josza algorithm gives the result in one operation of the type of a $(0,1) \mapsto (0,1)$ function $f(x)$, i.e. if $f(x)$, is constant or balanced. With the parallel computing power of a ...
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Neglected Term in the energy gradient for Variational Monte-Carlo
I'm looking into variational Monte-Carlo to determine the optimal variational parameter that corresponds to the ground state of a Hamiltonian. In general I am interested in tight binding models where ...
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Could a computer unblur the image from an out of focus microscope?
Basically I'm wondering what is the nature of an out of focus image. Is it randomized information? Could the blur be undone by some algorithm?
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How to define an equitable success event in quantum-walk-based multiple-targets search algorithm?
In quantum search algorithms (on a 2D grid or other setting), when there are multiple targets, a "successful search" event is often defined in following:
$$P_{success}=\max_{t\in [0,T]} \...
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Checking inverse metric and Christoffel symbols for the Kerr metric against references
I am trying to cross-check the Christoffel symbols and other very laborious geometric components in several metrics. In particular the Kerr metric is notoriously complex and results in expressions ...
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Multilateration of a light source in a medium whose index of refraction varies with position
Background
I have a set of $N$ receivers whose locations in $3D$ space are well-known. These receivers are immersed in a medium whose index of refraction (and thereby the velocity of light propagation)...
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About how to calculate observables in Quantum Monte Carlo with complex weights
I'm rewriting a Diagrammatic Quantum Monte Carlo algorithm following Werner, P., Oka, T., & Millis, A. J. (2009). Diagrammatic Monte Carlo simulation of nonequilibrium systems. Physical Review B, ...
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Can I find quantum circuit drawing of BB84 protocol somewhere?
Quantum algorithms and protocols are often expressed as circuit diagrams. But I have not been able to find the circuit diagram of BB84 protocol. Has anyone seen one?
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Is there a proof for critical slow-down in Monte Carlo?
It is physically understood why the standard Metropolis-Hasting algorithm slows down near the critical temperature, since it doesn’t utilize the divergence of the correlation length. However, I’m ...
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Force-simulation for graph layout: How to avoid particle collapsing into a single point?
In a force-based graph-layout simulation using Barnes-Hut, what are the conditions for collapse? With collapse I mean multiple (or even all) nodes "collapsing" into a single point.
Is there ...
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Any quantum Monte-Carlo algorithm for calculating the lowest eigenenergy in each symmetry sector?
Suppose we have a hamiltonian which has the parity symmetry (e.g., the Heisenberg model with the open boundary condition). Is there any quantum Monte-Carlo algorithm which can be used to calculate the ...
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Is Quantum State Tomography (QST) an inherently supervised or unsupervised problem in Machine Learning?
I am studying how to apply neural networks to the problem of Quantum State Tomography (QST) and I got confused when it comes to decide if this is a supervised or unsupervised learning problem.
At ...
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