Simulations Definition and 116 Threads

I have been reading in papers here and there, that di/multi-jet MC generated or even other process that have one or more associated jets are used for tag-and-probing or for training several BDTs and so on. Some experiticians (theoreticians who produce experiments) are also relying on how well...

I have an integration that doesn't have a solution in the table of integrals. So, I evaluated it using Mathematica using the command NIntegrate. However, when I compare the result with Monte-Carlo simulations, there is a very small constant gap between the two curves. Is it because of the...

I want to simulate STM images of some compound composed of 3 molecules A, B and C.. Which is the right way to do the simulations? *Use the known equilibrium geometries of A, B and C as input for simulating the compound? or *First optimize the geometries of A, B and C independently and then use...

Hi, I am trying to fully understand the meaning and usage of phase space in the various contexts it's used. For example particle physics, classical mechanics, statistical mechanics, thermodynamics, relativity. Also, there is configuration space, parameter space, and state space. How are all of...

Hello! As the title states, I want to get myself a new rig for simulating complex physical phenomena. Specifically, I'm going to run quantum chemistry/solid state physics/atomic physics calculations on it. I'm planning to re-use some parts of my old PC, and buy some new ones. I want to spend...

I am trying to model metal NPs capped with organic agents to simulate their phase transfer behavior from aqueous to organic. Not doing computational chemistry courses has had me to disadvantage. Would love some initiation or a jump start primer for the same. Looking forward for cues to get me...

Hello. I am not too sure if this thread is the right place to post this in. But anyway. I have to make a project for my final year, and I have chosen to make a quantum mechanics based project. I am thinking of doing some quantum mechanics based simulations, give a little bit of history of...

http://arxiv.org/pdf/1511.01098.pdf We conclude that the “problems” often cited as challenges to ΛCDM are resolved in simulations that reproduce the dynamical constraints of the Local Group environment and include a realistic galaxy formation model. Reionisation and supernova feedback allow...

I'm preparing a poster presentation on the following paper for a physics course: http://t.co/xiCLV7Y0ZH I do not understand how figure 4 tells us about the red/blue shift. Just from the deflections of the peaks of the airy beam, as well as the deformation, how are we able to infer that there is...

I've designed a 3rd order BPF. I tuned it in AWR Design Environment (Microwave Office), and got the response I wanted: However using the same component values with LT Spice gives me a different response: The other thing I've noted in the plot is the input voltage. I'm not that familiar with...

Dark matter particle candidates are being searched at CERN and the various dark matter models are being probed by cosmological simulations. The usual way to probe models via cosmology is to plug a candidate into a cosmological simulation and then compare the results with observations. Yet...

I understand that the first cosmological computer simulations Did not have DM Only gas dynamics on expanding grids And, that those sims produced no structure of any kind No LSS Only vast expanses of nearly uniform space plasma Devoid of any clumps Essentially reminiscent of the real...

There are numerous publications about pairwise velocity dispersion ( PVD ) of galaxies in real redshift surveys. It is customary to use an exponential form for the distribution of pairwise velocities and then model the redshift space distortions in the 2PCF to retrieve the PVD. Now if i have a...

In the Hubble Ultra Deep Field photograph, they show a 3D simulation of traveling through it. (Cue to about 2:00 minutes.) Obviously the simulation is traveling through that field faster than the speed of light. What would that field actually look like while traveling near the speed of light...

On first reading, the description of ‘group velocity [vg]’ appears to be quite straightforward. However, I also found a number of speculative explanations as to ‘how’ and ‘why’ the group velocity may exceed the ‘phase velocity [vp]’. Therefore, in order to get a better intuitive understanding of...

I am Post Graduate in Physics and working as a researcher in Non Destructive testing. I have heard about multi-scale simulations and its applications to material modelling. Iam intersted in learning mutiscale simulations for materials modelling. can anyone provide me links that would let me...

Hello, I would like to understand in detail what are the Light-Cone cosmological simulations and the difference between N-body cosmological simulations. If anyone is familiar with the topic i am open to an explanation or perhaps he could recommend me a review or an article about the...

Hi, Could you please recommend web resources with similar simulations as here: http://phet.colorado.edu/en/simulations/category/new thanks

I'm looking at some Materials Science graduate programs and some of the research areas involve simulation of material growth and properties. I'm kind of wondering what the value of this kind of research is as opposed to more practical research. This probably goes into the philosophy of science...

Can a computer simulation lead to a scientific discovery from an epistemic point of view? Do you know any of such discoveries throughout the history of physics?

In Monte Carlo simulation of classical spin systems I have a trouble to determine critical exponent ##\alpha##. ##M \propto L^{-\frac{\beta}{\nu}} ## ## \chi \propto L^{\frac{\gamma}{\nu}} ## ## C_V \propto L^{\frac{\alpha}{\nu}} ## Is this correct? From that slope of the curve ##\ln Cv## as a...

I've gotten really interested in CFD and DFT recently. I have a BS in Chemical Engineering and will be 25 in about a month. Been working in the oil industry for the last 2 years and before that I worked in a carbon nanotube and graphene 'factory' for lack of a better term that I can come up with...

Hi. I read due interest papers in Arxiv. There is many times refereed to so called N-Body Simulations. Is that for Matter or Dark Matter? How does it work, can someone explain or suggest good readings? THX

So I've been playing with a little N-body code in 3D for gravitational problems and have made an OpenGL visualization to go along with it. I have been generating initial conditions (positions and velocities) using explicit formulas. I was wondering of anyone knew of any resources for getting...

Hi all, I am currently a junior in chemical engineering and want to go to graduate school for it. I am extremely interested in the materials side of renewable energy. To make a long story short, I don't enjoy being in the lab much but really do enjoy thinking about it, researching, and...

Hello, Would someone please give me a list of free programs that I can use to simulate probability experiments/distributions. Such as drawing 5 cards randomly from a deck or rolling 5 sets of 20 sided dice. Or do I have to learn R or something?

Hello friends, I am new to MATLAB and I have been asigned a task in MATLAB to simulate basic equation.. I have no idea how to start.. The equation is Arterial pressure= Mean arterial pressure - h*7.46 (h= height) Can you tell me how to do please? thankx

Hello everyone! I have constructed a model of a silicon crystal, consisting of 64 atoms, for my various needs of testing physical phenomena in that substance(Silicon). At present, rather annoyingly, I am still stuck at the basic operational level, that is, calibrating the system to an expected...

Hello everyone, I am currently working on a classical MC simulation of helimagnets and I try to calculate the experimentally measured phase diagram. Up to now I am able to reproduce a large piece of the phase diagram by using a single site Metropolis update and simulated annealing...

From http://www.lsbu.ac.uk/water/models.html, I see that are many models of water that can "explain" one or some properties of water but no model is accurate enough to explain all the properties of water. From what I understand, all models assume classical mechanics interactions...

Does anyone know of any computer programs that can be used for quantum mechanics applications?

Hey, I've simulated a solid metal cluster of gold fcc100 And a surface Platinum in fcc111 using a classical mechanical approach. Do you think i could get the surface free energies(the ones to use in determining the Wulff shape) from periodic boundary conditions and if so how? I am really...

i'm looking for computer simulations of expanding space. i made a couple of very very very simple models and my results were no where near our current model of space. hence, I'm looking for work that has already been done on the subject.

I'm looking for what might be best for simulating various physical phenomena - some examples off the top of my head might be how to create an animation of a double-pendulum, or a system of 250 particles that are mutually interacting, confined within some box, in an arbitrary external field (like...

Hi! I am Giulia, and I hope the following message is of interest to some given the topic.* I have just co-authored a book: "Friendly F#, fun with game programming and XNA". The book aims at teaching the F# language through a series of samples that are fully centered on physics simulations...

Hi, as you all know, current cosmological N-body simulations (like the Millenium run) are based on the Newtonian limit. Gravitational fields are supposed to be rather weak and therefore the force between dark matter particles reduces to Newtonian gravity. Other relativistic effects are...

I was wondering whether anyone has experience in astronomy simulations. If so, what language do you use and recommend? I've done Haskell and a very small bit of C++... I've been told Python is good, what are your thoughts? Also are there any good websites that may get me started? Thanks

I know Veriog simulators are event-driven and what matters is the moment that event happens. Suppose we have a code like, module inv (in, out); input in; output out; wire inv_s1; reg out; assign inv_s1 = ~in; assign out = ~inv_s1; endmodule My question is does inv_s1...

Hi, I am trying to analyze circuits with a capacitor, diodes (normal and zener) and load resistance. Was wondering if anyone knows of good simulations on the web. Had a search but didn't find anything decent except this www.alternate-energy.net but it doesn't have zener diodes... In the lab we...

Hi all... I am just starting off with the monte carlo methods... I have done some work with self avoiding walks and ising models.. Can someone suggest some project that can be taken on as part of a Master's thesis.. thanks..

Hi all, I recently was posting in another thread on how to properly integrate the equations of motion in gravitational simulations. I thought this would be a good opportunity to provide some basic knowledge on simulations, numerical differential equations, and a little bit of programming. I'm...

When can we expect to see numerical simulations of GR for cases that are not highly symmetric? Say 10^3 blobs of matter in an arbitrary initial configuration.

On web where I can find interesting samples, math, physics or nature simulations like this o: http://demonstrations.wolfram.com/"

In another thread, we were discussing Zonde's and the De Raedt's model for simulating Bell tests using a purported local realistic computer simulation. I have broken out into this new thread some results which will be interesting to those of you interested in this subject. I will start out by...

i am now reading a prl paper the authors used numerical simulations to study a nonlinear system in some parameters, the authors state that system enters into chaos My numerical simulations are the same as that of the authors in the regular regime but in the chaos regime, my...

i am now reading a prl paper the authors used numerical simulations to study a nonlinear system in some parameters, the authors state that system enters into chaos My numerical simulations are the same as that of the authors but in the chaos regime, my simulations are quite different...

Hello all, OPEN FOAM is an open source program for performing CFD (Computational Fluid Dynamics) simulations. Here is the hompage for it. http://www.opencfd.co.uk/openfoam/ It requires a good deal of source code interaction in order to run. (So I have been told.) That is why I...

Hi all! This may have been previously posted before but check it out! Just discovered this today. It's really cool. Great for getting an intuitive feel for what is happening in circuits. Try hovering over the components to get simulation info of each component...

Hello, I have been running spin evolutions with 8 spin 1/2 nuclei, but I am having issues increasing the number of spin 1/2 nuclei to 12. I get the following error message in command prompt. Firstly Spinevolution appears to be loading as normal, but then after a minute or so the simulation...

hi, I am a PhD student and I'm looking for a course or resources on the hadronic jets and the models used to deal with them in the code simulation GEANT4. (Example: Bertini model, cascade ...) I will be very greatfull if you can help me. Thank you in advance Sameh