I have recently read the 2014 book “Reality is not What it Seems”, by Carlo Rovelli, an acclaimed theoretical physicist. The book is about the current status of quantum gravity research, also called loop quantum gravity, and it is written for us laypeople. The implications of quantum gravity are mind boggling. While I don’t fully understand the book, I got enough to be thoroughly dazzled. Rovelli gives the reader an extensive history of physics, going back to the Ancient Greek philosophers.

Quantum gravity theory tells us, in brief, that space is not the smooth, continuous expanse that we usually think of. Space is a network whose nodes represent grains or quanta of space. Space is a field. Space is not infinite, nor is it infinitely divisible. There is no place for infinity in quantum gravity theory.

Matter does not consist of particles moving in space. Quantum mechanics has already done away with the particle as a thing concept—there are only quantum fields. The world is a sequence of discrete events. A particle is a temporary event, an interaction of fields, or lines within a field.

Reality does not consist of matter moving in space and time. Reality is made out of fields—covariant quantum fields which are primary. Everything that we think of as existing: matter, light, energy, space and time—all are manifestations of covariant quantum fields. According to Rovelli what we perceive as reality is a crude and symbolic version of the quantum gravity field. In this higher reality there is no such thing as time, just relationships.

The ideas are hard to fathom, but this subject whets my already almost religious worship of nature with all its awe-filling mystery. I highly recommend the book. Do not be deterred by my wide-eyed spiritual orientation—Rovelli is safely in the atheist camp.