One need not be a poet or a mystic to find Blake's definition of energy more satisfying than
the defini tions given in textbooks on physics. Even within the framework of physical science …

THE behaviour of matter and energy represents one aspect only of human knowledge,
which is generally known by the name of physical science. It seems well to state at the outset …

ENERGY CAN NEITHER BE CREATED nor destroyed. This principle, called conservation of
energy, is one of our most cherished laws of physics. It governs every part of our lives: the …

This paper explores the evolution of Einstein's understanding of mass and energy. Early on,
Einstein embraced the idea of a speed-dependent mass but changed his mind in 1906 and …

Energy and Mass in Relativity Theory presents about 30 pedagogical papers published by
the author over the last 20 years. They deal with concepts central to relativity theory: energy …

What determines the struc ture of space and time in the universe? According to Ein stein's
general theory of relativity, the geometric properties of space are related to the density of …

(C op ernicu s) where, we are led to the conclusion that the universe must be permeated by
an exotic form of energy, dark energy, that exerts a repulsive force. Nothing meeting the …

There is a persistent tradition, apparently starting with a paper by Ives, that Einstein's original
derivation of the mass-energy equivalence was fallacious." It has probably gained most …

energy became generally acknowledged, the conviction has also developed that this law
must serve as the foundation of the natural sciences, above all of physics. The realiza tion of …

First I provide some history of how the equation E= mc 2 arose, establish what “mass” means
in the context of this relation, and present some aspects of how the relation can be …