Recent content by Appelros

Oh, okay, are you working on something else interesting? I constructed the above mentioned MWE and fed the details to ChatGPT and it explained the solution, I thought AI would have huge problems with advanced physics but so far it has been very helpful.

Your latex switched from rendering to not rendering to rendering again while I posted my reply above, strange indeed. ##x^2##, now it works in preview. Sometimes it doesn't

Yea the Boris method solves most problems, but I can't get it to bounce at the analytical bounce point in a magnetic bottle. I might start a thread about that after I extract a MWE. Approximations can also be expensive, I found a plasma package that calculates the Vlasov equation but it would...

No one has provided an improved solution to scaling. Rotation would be a candidate.

Uh, I'm not... You seem to misunderstand/misrepresent everything I say and frankly it is not pleasant communicating with you. The primary objective of any communication should be building rapport.

In complex simulations the best that can be done analytically is solving for the force vectors at each time step, and whenever the perpendicular magnetic force vector is added to a velocity the velocity increases, which it shouldn't. That's why I came here for help. I tried to use code ticks...

The thread title clearly states this is about numerical simulations. Euler, midpoint and RK, with scaling, match Boris algorithm at an error of dt/2. You said there was a better way without scaling and hinted at averages, then ignored my reply interpreting your solution and showing it was worse...

No this is 3D vectors as they are written in Julia, python and matlab have similar notation. v is a vector with x value 1 and y/z 0. Why don't you write your solution? Does it have an error less than dt/2?

Yea optimization is certainly a major consideration, but first I have to get things working. Premature optimization is a waste, for example I recently scrapped almost all of one of my core files.

Well I use Julia and it doesn't really expose pointers.

Funny you should mention cyclotrons, I just today finished a simulation of one. That is an interesting coordinate system approach, I'll keep that in mind in my further studies. During COVID there was an app that gamified folding molecules to help vaccine research, I'm thinking of something...

You only have to pair particles that are close to each other. It seems you are projecting, I'm not doing that, you are the one discrediting my decades of mathematical knowledge and coding experience. I'm sure you are very knowledgeable in many fields but please try to be more polite.

Yes, approximative models will take up a large part of my project. The particle resolution sims are I guess motivated by my mathematical side seeking an "analytical" solution.

Every plasma course I have taken has covered mechanics of individual particles so it seems like a good place to start. Training a neural network on the physics is also something I see that can speed things up a lot.

Yes. Ok, if I understand you correctly this is what you mean: ``` v=[1,0,0] d=[0,0,0.1] vavg=(v+(v+d))/2 -> [1,0,0.05] ``` Sure it's an improvement but the magnitude still increases. Scaling coincides exactly with the Boris algorithm and I don't think taking an accuracy loss to be more...