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5
votes
2answers
210 views

Classically efficient universal quantum computation (P=BQP) with magic and bound states

$\text P$ vs $\text {BQP}$ is an open question. That is, "can systems which require a polynomial number of qubits in the size of an input be described with only a polynomial number of bits?" If the ...
5
votes
0answers
80 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 ...
0
votes
1answer
110 views

Turbulence, Numerical simulation [closed]

How hard is numerical simulation of 2D turbulence and what is the best way to do it? Is there a software with this purpose?
1
vote
1answer
111 views

Simulation of an one dimensional driven diffusive system [closed]

I'm currently writing a simulation in python with scipy and matplotlib to reproduce an one dimensional driven diffusive system described in this paper from M.R. Evans et al. The system consists of ...
4
votes
1answer
175 views

How to calculate the new positions of other vertices in spring-mass system graph, when one vertex is actively moved by the user?

I am developing an android based game. I have 10 soldiers uniformly spaced in the scene using some kind of formation. Example - banks of 3 3 and 4 or banks of 4 4 2 or banks of 4 2 and 4 etc... Now ...
2
votes
0answers
218 views

For two planets in a 2:1 mean motion resonance , where will their periastron and apastron points be?

I want to animate the changing orbits of planets when they enter a mean motion resonance. Using a 2:1 resonance, I want to show a low-mass inner planet and a low-mass outer planet being tugged by a ...
3
votes
3answers
254 views

Computation theory and the simulation argument

Can physical states be treated as information (strings over some alphabet)? If (1) is true, isn't this a trivial conclusion that the universe can be simulated by a Turing machine or a cellular ...
2
votes
1answer
958 views

Calculating specific orbital energy, semi-major axis, and orbital period of an orbiting body

Is it possible to calculate the specific orbital energy $ϵ$, the semi-major axis $a$, and the orbital period $T$ (or $P$) without any of them being available to you? The values I do have available to ...
3
votes
3answers
116 views

Numerical relativity coordinate system displayed

In a picture or video of a numerical relativity simulation, such as a neutron star merger into a black hole, how do they set up their coordinate system? Lets take the point in a video corresponding to ...
7
votes
1answer
746 views

Riemann invariants…Any physical interpretation?

I am really new to the CFD simulation, and started some simple algorithms recently. I then got introduced to the Riemann Invariants. Can any one provide some physical interpretation? Also, why is ...
1
vote
1answer
107 views

Why NPT ensemble is used for solid state phase transitions?

In Monte Carlo simulations of solid state phase transitions, why often Isobaric Isothermal ensemble (NPT) is used ? Why not NVT ? Here, N is number of atoms, P is pressure, T is temperature and V is ...
2
votes
0answers
163 views

simple MHD simulation code for (self) education and play with [closed]

I would like some super simple computational code for solving magnetohydrodynamics problems. High accuracy nor performance is not my concern. I wan't it just to visually explore qualitative behavior ...
6
votes
2answers
241 views

Physics and math behind flight through solar system: Where to start?

I wrote a first program that simulates a solar system. I was able to calculate the locations for every planet on its elliptical route for any given time. In a second program i managed to simulate ...
0
votes
3answers
198 views

Meaning of “Gradient with respect to coordinates of particle” in SPH

I'm currently trying to implement a simple SPH simulation based on a variety of papers. However as I'm not a trained physicist nor mathematician I have a small issue with the following notation and ...
2
votes
1answer
269 views

Dynamic simulation of surface tension [closed]

Is there any substantial body of work in physics on dynamically simulating effects of surface tension on liquids? The texts i found so far on fluid dynamics all seem to ignore surface tension, ...
3
votes
2answers
153 views

Can the axis of rotation of a celestial body point in any arbitrary direction?

I am developing a small computer program that involves moderately simple simulation of elliptical Kepler orbits for fictional, generated star systems. I'm doing this without much prior knowledge of ...
0
votes
0answers
62 views

Outflow for fluid simulation based on “Stable Fluids”

I've implemented a fluid simulation based on the paper Stable Fluids. It works quite well, except I would like to have the velocity at the "upper" edge just to outflow and not to re-enter on the ...
4
votes
1answer
247 views

Light scattering vs roughness

I've been searching for an answer to this question in professional circles for a while; now I'd like to ask here, to find out why the answer is not there :) In my optical modelling (computer ...
0
votes
1answer
473 views

Bouncing ball simulation computer science

In my Computer science class I was given a problem where I have to simulate a bouncing ball using "real physics". I have been trying to find a equation that will simulate the height of the bounce ...
1
vote
1answer
56 views

Function for heating of a planet by its star

I'm looking for an algorithmic model which will gives rough estimate of the average temperature of a planet's atmosphere (good enough to say whether there will be liquid water anywhere, or if metals ...
6
votes
1answer
730 views

What are the limitations of Smoothed-Particle Hydrodynamics?

I've been excited by some of the possibilities of Smoothed-Particle Hydrodynamics (SPH). I have seen some very exciting demonstrations of their use in 3D graphics, but I am wondering how well the ...
3
votes
0answers
56 views

Modeling the formation of a stellar system and matter accretion

I am trying to figure out what do I need to know to properly simulate the creation of a solar system from a particle cloud with random distribution of hydrogen atoms. Being more of a programming ...
1
vote
1answer
173 views

Fitting a circuit scheme to a simpler model

I have to simulate the electric field within a gas filled discharge gap generated by a radio frequency voltage generator. The circuit, provided to me by the experimenters somewhat far away, is given ...
1
vote
3answers
305 views

Magnetic B Field of Point Charge Not at Constant Velocity

I'm working on an N-body simulator for charged particles. I know that moving charged particles generate a magnetic field, and another moving charged particle could be effected by this magnetic field. ...
0
votes
0answers
76 views

Molecular dynamics simulation: fluctuating dipole model implementation

I'm conducting a molecular dynamics simulation for silica. Some time ago I turned to the fluctuating dipole model, and after much effort I'm still having problems implementing it. In short, all ...
-3
votes
1answer
144 views

How do we simulate Nuclear explosion? [closed]

I am interested in PC simulation, i use physics equations to simulate rain, fire, wind, cloud and lightning. it is a kind of VR (virtual reality). what equation is able to simulate a virtual nuclear ...
16
votes
2answers
988 views

Why can't Humans run any faster?

If you wanted to at least semi-realistically model the key components of Human running, what are the factors that determine the top running speed of an individual? The primary things to consider would ...
1
vote
1answer
113 views

Deriving the change in the Helmholtz free energy in the context of the free energy perturbation method

I am reading Free Energy Calculations: Theory and Applications in Chemistry and Biology by Chipot and Pohorille. At the beginning of the text (page 19, for example), the authors define the Helmholtz ...
0
votes
2answers
361 views

I want the Saturn's position in terms of Declination and Right Ascension?

I want the Saturn's position in terms of Declination and Right Ascension for a couple of month in the interval of 1 hour in a text file to do a simulation. Which site can provide me these data? Or, ...
2
votes
1answer
362 views

Simulations of Planetary Motions

I wrote a spreadsheet that simulates the trajectory of 3 planets in 2D space. The method is simple: for each moment in space, calculate the force felt and velocity of each planet, then for the next ...
4
votes
0answers
106 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 ...
2
votes
1answer
174 views

Local minima in Ising model in a Monte Carlo simulation

Is there any way to check whether in a Monte Carlo simulation using Ising model is stuck in any (false) local minima of energy or not, particularly in 3D system ?
3
votes
2answers
266 views

Erogodicity in a Monte Carlo simulation

Q1: What is the ergodicity and ergodicity breaking in a Monte Carlo simulation of a statistical physics problem? Q2: How does one ensure that the ergodicity is maintained ?
-3
votes
2answers
147 views

Argument against computer consciousness [closed]

Imagine that we have a computer program that produces the conscious awareness of the present moment. Let us assume that every time the program is run a counter is incremented. Let us also assume ...
1
vote
1answer
95 views

Simulating an orbit, primary is not at focus

I've been toying around with some -very- simple orbital simulators, mostly using preexisting physics libraries (I took a layman's stab at doing it with vectors too). The thing that is confusing me is ...
0
votes
0answers
49 views

Should a 1D Guassian wave oscillate?

I wrote a few lines that numerically solve Maxwell's equations. The result is a moving wave that looks like a single pulse. This looks strange to me because I expect waves to move in oscillator ...
1
vote
1answer
48 views

What creates the differences between the two channels of a stereophonic signal?

Given two identical microphones arranged in an ideal XY pattern, recording a single sound source at equal distance from both capsules, the two signals obtained are equal in amplitude, perfectly in ...
1
vote
1answer
254 views

How to get the new direction of 2 disks colliding?

I'm developing a 2D game including collisions between many disks. I would like to know how I can get the angle corresponding to the new direction of each disk. For every disk I have this information ...
5
votes
0answers
57 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 ...
2
votes
2answers
103 views

How should I simulate the electric potential field from a wavefunction?

I was interested in making what I thought would be a simple simulation of an electron encountering a positron by numerically solving the Schrodinger equation over several time steps, but I've run ...
4
votes
2answers
946 views

How to calculate linar velocity of planet orbit?

I try to simulate a solar system with planets (with random mass) placed randomly around a sun with a mass $X \times \text{solar mass}$. The simulation is going well when I use real data ...
0
votes
2answers
180 views

Planet's Moon attrated by sun [closed]

I'm currently writing a code to generate solar system and $N$ number of planets / moons. I use real data to test (earth / sun / moon data). I succeeded in placing the earth and make it orbit around ...
0
votes
1answer
382 views

How to simulate temperature change of oven?

I am trying to write a software, which will model the oven temperature change when turning on/off. The data I can get is graph, by taking temperature reading each second from T0 time up to some ...
2
votes
1answer
107 views

neutron transport approximations for nuclear rocket modelling

I'm pretty ignorant regarding neutron and nuclear transport modelling, but i'm interested in trying to pursue it for a particular pet project. It regards modelling of nuclear reactions like those ...
6
votes
1answer
280 views

Why do air bubbles stick to the side of plastic tubing?

I'm watching water with air bubbles flow through transparent plastic tubing. The inner diameter is a few mm. Bubbles typically are the same diameter as the tubing, with length about the same or up ...
7
votes
1answer
239 views

Simulating the evolution of a wavepacket through a crystal lattice

I am interested simulating the evolution of an electronic wave packet through a crystal lattice which does not exhibit perfect translational symmetry. Specifically, in the Hamiltonian below, the ...
0
votes
1answer
346 views

Are We Living in a Simulated Universe? [closed]

If the universe is just a Matrix- like simulation, how could we ever know? Physicist Silas Beane of the University of Bonn, Germany, thinks he has the answer!. His paper “Constraints on the Universe ...
1
vote
0answers
27 views

Rolling (without slipping) ball on a moving surface 2 [duplicate]

Possible Duplicate: Rolling (without slipping) ball on a moving surface Apparently I didn't log in properly when I asked a question this morning: Rolling (without slipping) ball on a moving ...
2
votes
1answer
528 views

Rolling (without slipping) ball on a moving surface

I've been looking at examples of a ball rolling without slipping down an inclined surface. What happens if the incline angle changes as the ball is rolling? More precisely I've been trying to find ...
5
votes
1answer
178 views

Convert latitude of lowest altitude to argument of perigee?

I am designing an orbit around Mercury. I know the values I want for the semi-major axis, eccentricity, inclination, and RAAN. I want the altitude of closest approach (periapse) to occur at ...