His research interests also include cosmology, elementary particle theory, the foundations of quantum mechanics, and theoretical biology.

His interest in physics began at that time when he read Einstein's reflections on the two tasks he would leave unfinished at his death: 1, to make sense of quantum mechanics, and, 2 to unify that understanding of the quanta with gravity.

[6]: 12  Shortly afterward, he browsed the Physics Library at the University of Cincinnati, where he came across Louis de Broglie's pilot wave theory in French.

"I still can close my eyes," Smolin wrote in Einstein's Unfinished Revolution, "and see a page of the book, displaying the equation that relates wavelength to momentum.

"[6]: xxviii  Soon after that he would "talk his way into" Hampshire College, find great teachers, and get lucky in his applications to graduate school.

Smolin contributed to the theory of loop quantum gravity (LQG) in collaborative work with Ted Jacobson, Carlo Rovelli, Louis Crane, Abhay Ashtekar and others.

Between 1999 and 2002, Smolin made several proposals to provide a fundamental formulation of string theory that does not depend on approximate descriptions involving classical background spacetime models.

Because the theory applies the evolutionary concepts of "reproduction", "mutation", and "selection" to universes, it is formally analogous to models of population biology.

[citation needed] Later this figure was raised to two solar masses following more precise modeling of neutron star interiors by nuclear astrophysicists.

Smolin has contributed to the philosophy of physics through a series of papers and books that advocate the relational, or Leibnizian, view of space and time.

It argued that science progresses fastest if the scientific community encourages the widest possible disagreement among trained and accredited professionals prior to the formation of consensus brought about by experimental confirmation of predictions of falsifiable theories.

He proposed that this meant the fostering of diverse competing research programs, and that premature formation of paradigms not forced by experimental facts can slow the progress of science.

Finally, The Trouble with Physics is also broadly concerned with the role of controversy and the value of diverse approaches in the ethics and process of science.

I have studied most of them in depth and thought hard about them, and in the end I still can't make real sense of quantum theory as it stands.

[19] Smolin has stayed involved with theatre becoming a scientific consultant for such plays as A Walk in the Woods by Lee Blessing, Background Interference by Drucilla Cornell, and Infinity by Hannah Moscovitch.