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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$N$-body gravity simulator: why does energy conservation break down when introducing an adaptive timestep?
I am playing with an N-body gravity simulator using the velocity-verlet algorithm. In the actual simulation I normalize everything so that it is nicely behaved numerically, but I'll express things in ...
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What the difference is between Størmer Verlet and regular Verlet method?
I was wondering what the difference is between the Størmer Verlet method and the regular Verlet method, if there is any.
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Using a time-like boundary as a computer?
Question and Summary
Using classical calculations and the Robin boundary condition I show that one calculates the anti-derivative of a function within time $2X$ (I can compute an integral below)
$$\...
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Is photon interference really random? [closed]
I know that according to the many worlds interpretation, there is no randomness and rather there is a universal wave function that simulates an observer with a continuously branching timeline. My ...
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Could you use the Barnes-Hut algorithm iteratively-- with multiple center quadrants?
I was wondering if you could use Barnes-Hut simulation beyond what it was originally intended to be. For many Barnes-Hut algorithms, the forces are only considered for a single quadrant, the centroid, ...
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Using the Kalman filter given acceleration to estimate position and velocity [closed]
I am reading data from an accelerometer. I want to use this data to estimate velocity and position. Originally, I performed a double integration of acceleration to read this data, and as confirmed by ...
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Shor's algorithm with adversary - can (delayed) erasure of value qubits cripple calculations?
Let's look at quantum subroutine of Shor's algorithm:
Hadamard gates create superposition of all (exponential number) values for input qubits.
Then we perform a classical function on them, which is ...
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Have there been any patented physical models or computational algorithms? [closed]
There was a recent question (linked below) on the Law SE about the potential to patent algorithms. It appears there is a lot of gray area in the subject.
Of course natural laws cannot be subject to ...
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verlet/leapfrog method lorentz force application
So I ll use leapfrog/varlet algorithm to calculate the trajectory of the particle
In leapfrog method for initial values we need $v_{-1/2}$ and $x_0$. Hence I can write
$v_{-1/2}=v_0-Δt/2a_0$
$v_0$ ...
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Time for Quantum Computational Prime Factorisation
I ran into this graph where the red one is
$$x^3$$
and represents the number of steps as a function of factorised bits for a quantum computer. The blue graph represents the classical computer and has ...
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What is order of the Wolff Cluster algorithm?
What is the order of the Wolff Cluster update algorithm for Ising Model 2D and 3D?
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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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MEMS gyro measured angular velocity vector
Notations I use:
Consider a world frame $\{O_0, \vec{i}_0, \vec{j}_0, \vec{k}_0\}$ coordinate system and a rigid body $B$ with a coordinate system $\{O_1, \vec{i}_1, \vec{j}_1, \vec{k}_1\}$ attached ...
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Adiabatic QC: are there known difficult problems with spectral gap not exponentially decreasing?
Adiabatic quantum computers require slow evolution to maintain global minimum: $O(1/g^2)$ time, where $g$ is spectral gap: distance between two lowest energies.
The danger is that this spectral gap ...
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Quantum Approximate Optimization Algorithm
I try to understand the 'Quantum Approximate Optimization Algorithm' (QAOA) by Farhi et al. - arXiv:1411.4028.
I understand that the solution is hidden in the unitaries, but I do not understand how ...
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