Bernard Howard Lavenda (born September 18, 1945) is a retired professor of chemical physics at the University of Camerino and expert on irreversible thermodynamics.

He has contributed to many areas of physics, including that of Brownian motion, and in the establishment of the statistical basis of thermodynamics, and non-Euclidean geometrical theories of relativity.

He was also a proponent for the establishment of, and scientific director of, a National (Italian) Centre for Thermodynamics, and has acted as scientific consultant to companies such as the ENI Group, where he helped to found TEMA, a consulting firm for SNAM Progetti, ENEA (Italian National Agency for New Technologies, Energy and the Environment), and the Solar Energy Research Institute in Golden, Colorado.

Professor Lavenda currently lives in Trevignano Romano near Rome, is married with two adult children and two grandchildren, for whom his textbook "A New Perspective on Thermodynamics" is dedicated.

Having passed the entrance examination for the doctoral program at the Weizmann Institute of Science, he began experimental work on enzymes under the direction of Ephraim Katzir, who was later to become the President of Israel.

Realizing that he was not made out for experimental work, he came under the influence of Ephraim's brother, Aaron, after reading his book Nonequilibrium Thermodynamics in Biophysics, coauthored with Peter Curran.

After receiving his doctorate from the Universite Libre de Bruxelles, with la plus grande distinction, he returned to Israel in 1970 to work as a post-doctoral student in the Physical Chemistry Department of the Hebrew University.

During that period he published a short note in the Italian physics journal, Lettere Al Nuovo Cimento [3 (1972) 385-390] criticizing the Glansdorff-Prigogine universal criteria of evolution which attributes an inequality to a potential which is a function only of intensive variables, the forces.

During a sabbatical year in 1986 in Porto Alegre, Lavenda had ample time to browse through the well-furnished library at the Universidade Federale di Rio Grande del Sud.

A new magnitude-frequency relation is predicted which applies to clustered after-shocks in contrast to the [Gutenberg-Richter law] which treats them as independent and identically distributed random events.

Capturing the interest of the ENEA, or the Italian agency for alternative energy resources, he applied for funding in the European Commission of Human Capital and Mobility Programme.