LOVE OF PHYSICS & COSMOLOGY

                             One of the deepest philosophical questions is: why is there something rather than nothing? A more tractable question is: why is there space and time even when there is no matter? Most things in physics are represented as fields, continuous functions defined over space and time. There are electromagnetic fields, matter fields, strong and weak fields. All of these fields have what is called a “ground state”, a state in which they exist at their lowest energy level. In classical physics, the physics of Newton, Lagrange, Hamilton, and even Einstein’s relativity, fields tend to have zero ground states. For example, if I do not have anything charged around, I can expect that there will be no electric field around either. The electric field is in its ground state where there is nothing there to disturb it and make it active. The one fundamental theory in classical physics that I know of that...

  The British theoretical physicist Paul Dirac (1902–1984) one of the founders of quantum mechanics, once wrote: “There was difficulty reconciling the Newtonian theory of gravitation with its instantaneous propagation of forces with the requirements of special relativity, and Einstein working on this difficulty was led to a generalization of his relativity — which was probably the greatest scientific discovery that was ever made.” General Relativity is generally recognized as a theory of exceptional beauty. Several tests, along the years, confirmed the consistency of the theory. I will describe  one of the tests , which correctly explained the “anomalous” precession of the perihelion of Mercury (see  link ), which  Newton’s theory of gravitation  failed to predict.                                                      ...