# Questions tagged [simulations]

The tag has no usage guidance.

292 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
238 views

### What's the cause of this gap in this simulation of the Nice model?

A previous question brought me to this video (which has a spectacular change at about 0:34). It shows the orbits of Jupiter, Saturn, Uranus, Neptune, and what appear to be trans-Neptunian objects. ...
768 views

### Boundary conditions on current carrying wire

I'm trying to simulate by finite elements method Maxwell equations for a current carrying wire. My 3d geometry consists of a cylinder and a box containing it. I will use a mixed formulation and ...
208 views

### Final-state baryons in $p \bar p$ collisions in Pythia

I'm trying to simulate inclusive $\chi_c$ production in $p \bar p$ collisions at very low energies (~ 5.5 GeV) using Pythia8 event generator. Leaving aside problems bounded with applicability of ...
88 views

### Animating the Bosonic String

I am interested in studying the classical solutions to the Bosonic string in flat 3+1 dim. spacetime by having them rendered a moving picture on a computer. This is partly for fun, and partly to ...
106 views

### Do systems of fermions take longer to equilibrate than systems of bosons for complexity-theoretic reasons?

This excellent paper by Scott Aaronson persuasively argues that computational complexity can be relevant for physical processes. In particular, what's hard for a hypothetical Turing machine to do may ...
164 views

### BEC in a rotating disc

Goodmorning everybody, I have to run a numerical simulation of a Bose-Einstein condensate on a rotating disc. Now, my problem is that I became suspicious about the equation I'm using, since the final ...
194 views

### $N$-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 ...
166 views

28 views

### Impulses in a Collision

The question I have is that of computing the impulse in a collision between two objects in real life (or in a scenario that is very close to real life). I wish to simulate collisions of objects of ...
45 views

### de Broglie vs Schrodinger models: Why is the IR spectra different in PhET simulation?

I was playing around with the PhET simulation "Models of the Hydrogen Atom", https://phet.colorado.edu/en/simulation/legacy/hydrogen-atom . In it you can simulate a hydrogen atom's electron ...
22 views

### Vehicle Drive Model - wheel and engine angular speed approach

I am trying to create a simple car simulation in 2D in Unity3D, I'm having a hard time figuring out the right approach. Say I have given the throttle percentage, I know the current engine's and wheels'...
64 views

### Unitary Coupled Cluster Operator

In quantum computing, we always want to deal with unitary evolution operators. That's why the traditional definition of the Coupled Cluster ansatz is modified to the so-called Unitary Coupled Cluster, ...
51 views

### "Unnatural" Hamiltonian systems from a statistician's perspective

I would like to learn more about "unnatural" Hamiltonian systems, that is, systems whose energies cannot be written as $$H(p,q) = K(q) + U(p).$$ I have seen the term "natural" applied to systems ...
38 views

### Is simulating 3D brownian motion in axially symmetrical 2D sensible?

I'm writing a Monte Carlo particle trajectory simulation program. There are fluid forces like the Stokes drag force involved, as well as Brownian motion. For runtime reasons, the program should be ...
74 views

### Determination of the thermal resistance of a molding tool with cooling channel

This is a section of cooling channels in injection moulding tools. I have tried to calculate the thermal resistance in this section with 2 methods, one analytical and one numerical. analytical ...
30 views

### How to simulate the formation of chemical bonds by calculating electrodynamic forces?

I had the idea recently that if the interactions between atoms could be calculated, that a large enough computer could simulate biological processes. What would I need to know to simulate something ...
65 views

### Is there a "standard" quantum simulator/animator for pedagogy?

I'm having a hard time finding animations for 1D or 2D square well, SHO, free particle with barriers, etc, that I'm sure are "trustworthy". It's the sort of thing I would do in python in my spare time ...
140 views

### How is the magnetic flux density inside a current tube affected by an inner wire?

Background to problem Conventional wisdom informs that the magnetic flux density inside a tube carrying current is zero everywhere. Pictorially this is represented by this finite element analysis (...
39 views

### Amount of particle collisions depending on entropy

I'm doing a very simple simulation of random particles. Simple mechanics, elastic collisions. (The simulation is based on a next-event time progression.) When I count the number of particle particle ...
87 views

### Magnetic susceptibility error by binning Monte Carlo

I am studying the 2D Ising model using Monte Carlo simulations and I have learned the binning (or batching) method for the error statistical analysis. Following this discussion https://books.google.it/...
84 views

### Geant 4, simulate Tc-99m decay

I have a setup of Monte Carlo simulations in Geant4, and I'm able to simulate radioactive events from isotopes such as I-131 and F-18, which are defined in the RadioactiveDecayData5.2 files. Tc-99m ...
38 views

### How to set the number of fermions in the whole system in fermionic-DMRG program?

In infinite DMRG (density matrix re-normalization group) algorithm, we increase size of super-block by two sites in each iteration. How do we set number of fermions in the system? Let's say we want to ...
42 views

### Stability criterion for leapfrog in relativistic physics

I am doing a 2D MD simulations of charge carriers in graphene using the Leapfrog algorithm. I am trying to prove that, in some specific cases (when distance between particles is small), the method is ...