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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Explanation of relaxation method for Laplace's equation?
Currently reading through Introduction to Electrodynamics (4th Edition) by Griffiths. I'm trying to wrap my head around Laplace's Equation, here are a couple quotes that I'd like to understand a bit ...
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Shor's algorithm - why doesn't the final collapse of the auxiliary qubits cripple the computation?
Let's look at quantum subroutine of Shor's algorithm (image source):
Hadamard gates create superposition of all (exponential number) values for input qubits.
Then we perform a classical function on ...
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How to calculate the maximal Lyapunov exponent(s) of a multidimensional system?
I've been reading up about Lyapunov exponents for a university group project on chaos theory and I'm a little confused as to how they are calculated for a system of multiple dimensions.
From what I ...
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Upper bounding the Kolmogorov Complexity of the Standard Model
The Kolmogorov complexity of a hypothesis/theory/model is the shortest computer program that simulates it, regardless of how inefficient executing that program may be in terms of memory and time. I'm ...
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Numerical Ising Model - Wolff algorithm and correlations
I'm doing some numerical Monte Carlo analysis on the 2 dimensional Ising model at the critical point. I was using the Metropolis 'single flip' evolution at first with success, though it suffers from ...
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How to actually find a Hartree-Fock ground state?
I am interested in finding the Hartree-Fock ground state for a system of interacting fermions (with totally local scattering, so a delta-function interaction potential). I have read through some ...
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Deutsch's Algorithm. Unitary Transform $U_f$
I'm studying Deutsch's algorithm and I keep coming across the phrase along the lines of "There is a unitary transform (a sequence of quantum gates) $U_f$ that transforms the state $|x\rangle |y\rangle ...
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Quantum XOR: How do you generalize it?
Consider the classical XOR Gate:
Given a 2 bit system: $G = [u_1, u_2]$
$$XOR(G) = (u_1 + u_2) \ mod \ 2$$
Is the following a good generalizaiton of a Quantum XOR Gate:
Given a 2-qubit system: $...
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Is estimation partition functions without resorting to markov chain monte carlo still an open question?
I was told estimation of partition functions without resorting to MCMC was still an open question in physics about a year and a half ago. An example is that say you have some physical model that ...
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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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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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Penning Trap Simulation
I'm currently working on a particle tracker and I would like to implement a Penning trap. I think I might have a problem with the field of the electrical quadrupole. My idea was to place 2 dipoles and ...
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Can I state that $\Psi (x_1, \dots , x_n,t)= \sum_{i=1}^n a_i \psi (x_i,t) $ via superposition?
Given that the hamiltonian $\hat H$ of a system is a linear operator and $\dot \psi (x_i,t)$ does not depend on spatial coordinates $x_1, ..., x_n$ with bases $\hat e_1, ... , \hat e_n$ can I state ...
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Shor's algorithm - its causality and similar exploitation of QM?
Shor's algorithm is rather the most interesting quantum algorithm as it shifts a problem which is believed to need exponential classical time, to polynomial time for quantum computer, additionally ...
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Sensor Array Position Calibration in Anisotropic Media
Problem.
I have a sensor array consisting of $n \gg 4$ receivers at unknown locations $\langle x_n, y_n, z_n\rangle$ embedded in an anisotropic medium whose index of refraction varies as a known ...
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