The Dreams That Stuff is Made of

by Stephen Hawking

  ot For hydrogen the quantitative results are not yet quite certain.

  ou Since kinetic energy is the product of [mass] × [velocity]2, this product will remain the same if the mass in creases by a factor 16 and velocity decreases by a factor 4. In fact, 42= 16!

  ov To avoid an objection on the part of those readers who know much more than necessary for understanding this discussion, the author hastens to state that, according to modern quantum electrodynamics, some scattering of light by light must be expected because of virtual electron-pair formation. But Jeans and Planck did not know this.

  ow Scientific Autobiography by M. Planck. Translated by F. Gaynor. New York: Philosophical Library (1949).

  ox Thephysicaldimensionofthequantumconstanthis a product of energy and time,or/erg·sec/inc.g.s.units,andisknowninin lassical mechanics as action; action appears in many important considerations, such as the Hamilton’s Principle of Least Action.

  oy During the early studies of electric phenomena, the French physicist Charles de Coulomb found that forces acting between charged particles are proportional to the product of their electric charges and inversely proportional to the square of the distance between them. This is known as Coulomb’s Law.

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  Introduction © by Stephen J. Hawking

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