How to simulate protons on a computer program to observe them?

[Sagar Bhatt]

Well I'm in grade 11 and for an investigation I decided I'd observe the behavior of protons once the neutrons and electrons are removed from the atom. Specifically I want to observe how the acceleration at which the protons move apart from each other varies with the mass of the atom (i.e. # protons) -- that's how I connect it to the course curriculum. At the time I thought I'd just construct the up-quarks and down-quarks and gluons and other stuff on a computer program using data from like Wikipedia, and then construct protons from that. (On a computer program I wouldn't have to construct the entire atom because I could choose when to start the experiment.) But I'm not so sure anymore. Btw I'm thinking of using something like Scratch. Or a physics engine. I'm afraid of the teacher's reaction to the proposal and about the seemingly impossibility-ness of this idea. Time to change proposal?

 

[mfb]

At the time I thought I'd just construct the up-quarks and down-quarks and gluons and other stuff on a computer program using data from like Wikipedia, and then construct protons from that.

This won't work. Even with all the scientific knowledge today, making realistic simulations of protons from scratch is still a huge challenge for scientists - there are approximations for many aspects, but it's not as easy as putting some particles together and then simulate them. The interior of protons is really complex.

It is not necessary, however. Nuclei can be described with the electromagnetic interaction and some effective attractive nuclear force only.

How do you remove neutrons from what?

 

[Orodruin]

Just to put mfb's comment into perspective, simulating the inner workings of a proton essentially requires you to do lattice QCD. This is a very active research topic and requires graduate level physics knowledge as well as high performance computer clusters. It is not something you can put on a laptop. It is definitely not "B"-level physics.

 

[e.bar.goum]

To put mfb's and Orodruin's comments into even more perspective, even simulating the behaviour of nuclei (your question is about collections of protons/neutrons) using an approximation that allows you to avoid doing lattice QCD (e.g. Time Dependent Hartree Fock methods) is still a topic of active research and requires high performance computing clusters! The next step down (arguably. e.g. shell model calculations) is also a topic of active research!

Perhaps, instead, you could use the Semi-Emprical Mass Formula to investigate what happens to the stability of nuclei as you vary the numbers of protons/neutrons?

 

[ChrisVer]

well I think you can do it as a normal electromagnetic interaction (for your level). Obviously you would have a many body system containing parts (protons) that each interact with the rest.
Using gluons is practically impossible, so you will just see how N-1 particles repulse the other... and how all these will move away from one another... I don't think it will be fun because the Fcoulomb~1/r^2 will give a very large 1st step push to all the particles.

 

[Sagar Bhatt]

Thanks for all the replies. I guess I'll change my proposal then.

 

[dragonfiremalus]

What would be fairly easy to do is just stimulating how fast charged particles that close together would fly away from each other in the absence of any force binding them. For that, there would be no need to go into quarks and gluons, you could just treat the protons as point masses and watch them fly ridiculously fast away from each other.

If, however, you wanted to simulate what the removal of neutrons would actually do to a nucleus, that's going to be much more difficult. My gut feeling (aka I'm kinda guessing here) is that you still could treat the protons as point charges and modeling strong and weak forces in some clever way.

I don't know how much is expected of you for this project, but I imagine just the point charges flying away from each other would be plenty to be going on with, especially if you increased the accuracy of your simulation using a Runge-Kutta method rather than a step approximation.

 

[Sagar Bhatt]

Thanks Dragonfiremalus. I'm not sure I'll return to this idea because I've been brainstorming new ones for my project, but in case I do do you think there could be a physical model for the point charges or would I have to do it online? And would I rather restate my research question in the submission to say point charges rather than protons?

 

[dragonfiremalus]

Thanks Dragonfiremalus. I'm not sure I'll return to this idea because I've been brainstorming new ones for my project, but in case I do do you think there could be a physical model for the point charges or would I have to do it online? And would I rather restate my research question in the submission to say point charges rather than protons?

Not entirely sure what you are looking for by the way of physical model, or doing it "online." If you are looking for an analogous physics demonstration similar to the bowling ball on a trampoline to visualize gravity, I don't know of anything for electromagnetism. You'd have to use computer simulation. But as for coding up a simple computer program to simulate it, I'd suggest using Processing, especially if you are at all familiar with C family syntax. https://processing.org/ It's very easy to do visualizations like that, as it has in my experience the easiest graphical output stuff (though I've never used Scratch, so I can't compare those).

 

[Sagar Bhatt]

Thanks.