How to simulate the entire universe using a laptop?

“A new tool, Effort.jl, is revolutionizing cosmology by letting scientists analyze enormous datasets quickly and accurately on a simple laptop. (Artist’s concept). Credit: SciTechDaily.com” (ScitechDaily, Researchers Have Discovered a Way To Simulate the Universe – on a Laptop)

How to simulate the entire universe using a laptop? The answer lies in the accuracy the system employs. When we want to conduct. In a comprehensive analysis or simulation of the entire system, we must first select the scale at which we want to simulate it. If we want to make a simulation of the entire universe, we must begin with its smallest parts. In this case, we must only remember that the system's entirety is the sum of multiple subsystems. An atom, as an example, is the sum of electron shells and the nucleus. 

The nucleus of an atom is the sum of the protons and neutrons. And protons and neutrons are sums of quarks and gluons. We can make the simulation step by step. First, we can make a simulation of interactions. Between quarks and gluons. Then we can connect these simulations. Together with the proton and neutron interaction. 

And then we can make simulations. Of how electrons behave with each other and then how electron orbits interact with the atomic core. In this case, the system handles the entirety as modules. Each module handles each participant. The proton module involves the up and down quarks. Interaction with each other. This means that the system creates a mosaic where each participant of the structure is handled. Like an element. The system forms a bigger structure by connecting the smaller mosaic plates. The system makes a puzzle. Where each piece is a smaller-sized system. And together. Those smaller systems form a bigger entirety. 

If we want to calculate chemistry calculations. And to make simulations. Between molecules, we must not know quark interactions. We can choose the scale as atoms or atomic groups. To make simulations of their behaviors. In molecular-scale interactions. Those interactions happen in the farthest electron orbital. So we must not care. About the internal interactions of atoms. Removing. Unnecessary parts from the simulations. We can remove too high accuracy. 

That means we remove unnecessary parts of the system. If we want to drive from point A to point B. We want to know what route we choose. We don’t want to know what kind of houses or what kind of trees. Are in certain areas. We don’t need to know when every single person comes home. We must not know there is a free parking lot if we are on a transit journey. We need to know only which streets we select. This means the system must remove unnecessary information to make our work easier. So, the system gives only information. That we need. 

When we talk about accuracy. We can think that the system must control small points in the simulations. If we want to make a complete simulation of the universe and start from the quark-gluon levels, there are too many points that the system must handle.  We should begin those simulations from a much higher level. Like in the level of local galactic clusters. That means . We must make a model. Where the details in the entirety are lost. That allows us to handle things like galaxies as one point or entirety. 

If we want to simulate the interactions between galaxies. We must realize that there are billions of galaxies in the universe. That makes this type of simulation hard to make. There are billions of stars in each galaxy. And all giant spiral galaxies are following large groups of star clusters and dwarf galaxies. 

But it's possible to handle those systems as a whole. In that model. The system makes ball-shaped structures. There, it removes details. So the galaxies are like balls that interact with each other. But then there are still too many objects. That means we can make another crop. We can select certain galaxies whose interactions we can analyze. If we want to make a simulation. 

To determine how the Andromeda galaxy and the Milky Way will collide, we must calculate the route that those galaxies follow. There, we need to see the effect. The Magellanic Clouds affect that route. Calculating that three-body problem is possible, if we do not follow the highest accuracy. There is a possibility that Andromeda travels past the Milky Way. And then those galaxies start to orbit each other. Closing together. Then in the last stage, the supermassive black holes collide in the middle of the new galaxy. 

But if we want to make universe-scale simulations. We must use a different scale of accuracy. We must not calculate all electrons and each electron's trajectories. If we want to calculate things like how stars or interstellar nebulae behave. We must change the scale of accuracy. To make a large-scale simulation. We must understand that we can cut off atomic-scale objects. If we simulate large entireties. 

In universe-scale simulations, it's important. To determine the thing. What we want to simulate. If we want to simulate interactions between two galactic superclusters, we must not calculate the interactions of each single galaxy. We can think. That those galaxies and even local clusters are the entirety at the level of cosmic superclusters. We can think that. The superclusters are like balls. The giant entities where the local clusters form the mass centers. Or we can simply think. That they are like giant balls. That makes the simulation of the galactic superclusters' interactions easy. 

https://scitechdaily.com/researchers-have-discovered-a-way-to-simulate-the-universe-on-a-laptop/