> Really? Can we actually simulate any part of the universe with 100% quantum accuracy? Lattice QCD has been used to simulate an entire proton[1] and derive it

> Really? Can we actually simulate any part of the universe with 100% quantum accuracy? Lattice QCD has been used to simulate an entire proton[1] and derive its mass to an accuracy of a few percent. [1]Popular descriptions of the proton simply call it a triplet of quarks, but it actually contains several virtual quarks too and a bunch of gluons with ever changing bonds and positions. The average amount of crap flying around inside the proton determines its mass, and you can find it by simulation.