All Questions
Tagged with computational-physicsalgorithms
66 questions
4votes
1answer
199views
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 ...
1vote
1answer
489views
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 ...
- 123
2votes
2answers
227views
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 ...
- 463
0votes
0answers
34views
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]} \...
2votes
0answers
84views
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)...
- 217
2votes
0answers
86views
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 ...
- 2,263
0votes
0answers
38views
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 ...
- 1
1vote
0answers
32views
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 ...
- 2,175
0votes
0answers
46views
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 ...
- 161
0votes
0answers
53views
Understanding chapter 3.1 (Laplace's equation) in Introduction to electrodynamics Griffiths 4 ed [duplicate]
I really need help to understand chapter 3.1. What is the method of relaxation? How can I use the method of relaxation to solve Laplace's equation? How can I use the first and second uniqueness ...
- 9
1vote
0answers
95views
Simplest quantum Monte-Carlo method for the Bose-Hubbard model
I want to use quantum Monte-Carlo results to benchmark an algorithm for the Bose-Hubbard model. There are so many QMC methods in the market, so which one is the simplest one? I want the ground state ...
- 2,175
3votes
1answer
192views
Grover's algorithm & using wave interference for computing
Grover's quantum search algorithm contends that it is possible to search for a specific item in an N-sized unsorted database in only $\sqrt N$ attempts. Classically, it takes N/2 attempts on average ...
- 627
1vote
0answers
516views
Which is more accurate: Euler's method or modified Euler's method?
I was solving a differential equation, the equation being, $$\frac{dv}{dt} = g-\frac{c_d}{m}v^2,$$ which can be solved analytically to give $$v = \sqrt{\frac{mg}{c_d}}\left(\frac{e^{2t\sqrt{\frac{c_dg}...
- 359
11votes
1answer
1kviews
Why use Crank-Nicolson over Matrix Exponential when solving Schrödinger's equation?
For Schrödinger's equation, $$\psi(x,t+\Delta t)=e^{-i H\Delta t}\psi(x,t)\approx\frac{1-\frac{1}{2}i H\Delta t}{1+\frac{1}{2}i H\Delta t}\psi(x,t).$$ The right-most expression is the Crank-Nicolson ...
- 779
0votes
0answers
167views
What are the advantages of tensor network algorithms over monte-carlo simulations in terms of time-evolution?
I understand that tensor networks and monte carlo simulations are based on completely different principles. However, to my knowledge both are used to simulate the time evolution of a system. Is there ...
- 343
