An excellent review of the development of the theories of modern physics. It contains rigorous math. I give one quote to give a sense of the book "The notion that an iether pervades all of space, including even that occupied by material bodies, was popularised in the 17th century by the philosopher Descarte~.~ Traditionally, space had been regarded as passive and unchangeable; an inert background, like a cinema screen, upon which any action can be projected but without which no action can be perceived. Descartes argued that in order to account for many physical phenomena, a dynamic active medium-an Ether-that transmitted the forces exerted at a distance by one object on another, had to be postulated."-