Plücker's student J. W. Hittorf... observed that solid bodies... near a small cathode would cast shadows... [and] deduced... the rays travel... in st… - Steven Weinberg

It is with Isaac Newton that the modern dream of a final theory really begins.

This is not intended to be yet another popular book that offers... the latest news in physics.
Still, it would be a pity not to show the links between the historic discoveries... and the work of fundamental physics today. I have therefore taken the opportunity... of this new edition to point out these links... I now carry the story of the discovery of elementary particles... to the present day.

In fact, there is something puzzling about the Higgs mass we now do observe. It is generally known as the “hierarchy problem.” Since it is the Higgs mass that sets the scale for the masses of all other known elementary particles, one might guess that it should be similar to another mass that plays a fundamental role in physics, the so-called Planck mass, which is the fundamental unit of mass in the theory of gravitation. (It is the mass of hypothetical particles whose gravitational attraction for one another would be as strong as the electric force between two electrons separated by the same distance.) But the Planck mass is about a hundred thousand trillion times larger than the Higgs mass. So, although the Higgs particle is so heavy that a giant particle collider was needed to create it, we still have to ask, why is the Higgs mass so small?