⚡️ Modern physics provides a precise language to capture the way things #scale: the so-called #renormalization_group. This mathematical formalism allows us to go systematically from the small to the large. The essential step is taking averages. For example, instead of looking at the behavior of individual atoms that make up matter, we can take little cubes, say 10 atoms wide on each side, and take these cubes as our new building blocks. One can then repeat this averaging procedure.

#Renormalization theory describes in detail how the properties of a physical system change if one increases the length scale on which the observations are made. A famous example is the electric charge of particles that can increase or decrease depending on quantum interactions. A sociological example is understanding the behavior of groups of various sizes starting from individual behavior. Is there wisdom in crowds, or do the masses behave less responsibly?

Most interesting are the two endpoints of the renormalization process: the infinite large and infinite small. Here things will typically simplify because either all details are washed away, or the environment disappears. Both the largest and the smallest structures of the universe are astonishingly #simple. It is here that we find the two “standard models,” of #particle_physics and #cosmology.

🔗 https://www.quantamagazine.org/to-solve-the-biggest-mystery-in-physics-join-two-kinds-of-law-20170907/