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It depends on what chips datacenters are using. If large data centers switch over to ARM-based processors, scientific computing will follow. Since most of our software is open source (or not far from that), converting to ARM compatibility will not be too much of an issue once the demand is there. Scientific computing is currently dominated by enterprise-...


16

I'd expect that x86_64 will remain the architecture of choice for computing throughput for quite a while, and that there might even be a way to deliberately re-enable the Spectre/Meltdown vulnerabilities because they give a nice speed boost and are irrelevant if you don't share the CPU with anyone else. ARM shines in the datacenter because a lot of the work ...


15

In the paper "A Continued-Fraction Representation of the Time-Correlation Functions", generalized susceptibilities and transport coefficients for materials are obtained using a continued-fraction expansion of the Laplace transform of the time-correlation functions. This was the precursor to what is now called the "hierarchical equations of ...


13

EDIT Doing what you want is hard! You will need a full quantum mechanics based simulation. This is unlikely to be something you can build yourself at the current time. Based on your new additions to the question what you need is Car-Parrinello or Born Oppenheimer MD. These essentially automate the idea of do a quantum electronic structure calculation, take ...


13

You may take a look at the Method of Continued Fractions used in quantum scattering theory—this was only formed in 19831 so is rather recent. Related is the PhD thesis by Kónya (2000)2; §3.3 onwards. Reference [1] Horáček, J., Sasakawa, T. (1983). Method of continued fractions with application to atomic physics. Physical Review A. 28(4):2151–2156....


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Any code that does not have core parts written in machine level code (assembly) is going to be portable to arm64 straight away; you just have to recompile the program. This is the whole point of having programming languages in the first place: you need to be able to run your program on different architectures without rewriting the program from scratch, like ...


12

How to proceed depends on how accurate you want the outcome. Throughout my answer I will provide blue buttons which demonstrate that there's entire tags in our community to address certain aspects of the simulation. What you are describing is (essentially) what we call molecular-dynamics even though you're dealing with atoms rather than molecules. In MD (...


12

The only proper way to do it ab initio is to calculate the energy (E) for various internuclear distances (R) and then to approximate the equilibrium bond length by choosing the distance which has the lowest energy, or by fitting the E(R) points to something like a Morse potential (which is decent for short-distances), Lennard-Jones potential (which is decent ...


11

Generally speaking, most work in molecular dynamics tries to simulate how actual molecules behave (i.e. quantum mechanics) and it doesn't sound like you want to go down that rabbit hole. I completely agree, but I'll begin with a disclaimer that looking up "molecular dynamics" probably won't turn up the kind of results you want. Since your comments ...


10

It's a very good question, and we may get several answers here from people with various different perspectives, but here is mine: In every case so far where we are certain that computations have been done thoroughly enough, known quantum field theories have been able to reproduce experiments when gravity is not strong enough to play a role. For example, QED (...


9

In order to simulate two atom interaction, you have different path to follow. One is to use Density Functional Theory (DFT) or ab initio, make a script where the distance of the atoms is decreasing, and for each distance, you calculate the system energy. The image below is the result of such calculation but between a metal atom and a carbon nanotube1. You ...


7

The main difference between ARM64 and x86_64 architectures is their core design. The x86_64 uses NUMA when more cores are involved, whereas ARM64 has a more versatile design, and can have unified memory access. The ARM64 design is less complex than the x86_64, and for highly parallel computing, a simpler design may help the performance. I see at least two ...


7

Unfortunately the answer to this question is much the same as your last one. What you are trying to do is hard. Very hard. Creating this would be PhD if not postdoc work and doing it well could well win you a nobel prize. From the comments you've made in this and your other question you do not appear to be a specialist in either physics or chemistry, and ...


7

The simplest possible atomic simulation: a noble gas As explained by Nike Dattani, what method you use depends on what you want to simulate and why. He gives you a good roadmap for what method to choose based on what you want to do. I wanted to take a different perspective. If you're familiar with writing code and want to program the simulation yourself, ...


6

I don't know why you need atom-atom interactions in a sandbox game. My only guess is that you want to simulate or visualize the movement of molecules of some kind in real time. If your system is large i.e. more than ~20 atoms, you have to resort to molecular dynamics to get reasonable speed. This has already been covered in detail in Max's answer, so I will ...


5

Get your parameters from an existing force field (UFF? ReaxFF?) People in the molecular dynamics world use established force fields to describe forces between different types of atoms. These force fields are mathematical functions that have parameters like bond lengths, bond angles, dihedrals, van der Waals radii, etc. Usually these parameters are obtained ...


5

The continued fraction expansion is the most common way to calculate real-frequency dynamical Green's functions using Lanczos exact diagonalization. The method was introduced in this setting in Gagliano, E. R., and Balseiro, C. A., "Dynamical Properties of Quantum Many-Body Systems at Zero Temperature," Physical Review Letters 59, 2999 (1987), but ...


4

ARM64 may not have to be the next big thing to cause a positive change. Competition between two standards could result in extensions of either standard to improve them. We already see vendor specific extensions making a big difference with intel vs amd for example. From what I have seen, as long as the software support is good (as others have pointed out, ...


4

The most trivial model to estimate bond lengths between two atoms is probably a simple sum of Van-der-Waals Radii. Just load a table with Van-der-Waals Radii and take the equilibrium distance for two atoms as the sum of the Van-der-Waals Radii of both atoms. This is by no means accurate but for the intention of the poster it might suffice. If this is still ...


3

I don't think you are looking for anything too physically correct so I think for your purposes, you can get away with a simple morse model. Consider which elements you would like to use, hopefully you can restrict it to basic organic elements such as C,O,N,H,Cl,B and consider which elements that need to be able to bond together. Prepare a table such that you ...


3

When I read your question I remembered a gitlab pages that list all the softwares ported to the arm architecture and their development progress. You can find it here: https://gitlab.com/arm-hpc/packages/-/wikis/categories/allPackages Hope this can help.


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