String Theory in Three Minutes

20th-century physics says everything is made up of point particles with a bunch of different properties. But where do these properties come from and where does gravity fit in? Particle physics is a bit of a misnomer — modern understanding suggests these particles are excitations in quantum fields. So, really, field physics is more appropriate — this is incomplete too since we fail to explain gravity. Turns out, we can get a self-consistent explanation of all particles and gravity if we concede that they’re tiny little strings. The way these strings vibrate determines their properties and ultimately, the particle. Instead of points tracing out lines (as in Feynman diagrams), these strings trace out two-dimensional surfaces as they move through space and time. This is how we describe interactions between them. <a href="https://medium.com/quantaphy/string-theory-in-two-minutes-df16ac87f707">Website</a>