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Planck solved the radiation problem by proposing that the vibrating particles can only radiate at certain energies. The permitted energies would be determined by a new number—“a universal constant,” he says, “which I called h. Since it had the dimension of action (energy X time), I gave it the name, elementary quantum of action.”278 (Quantum is the neuter form of the Latin word quantus, meaning “how great.”) Only those limited and finite energies could appear which were whole-number multiples of hv: of the frequency ν times Planck’s h. Planck calculated h to be a very small number, close to the modern value of 6.63 × 10−27 erg-seconds. Universal h soon acquired its modern name: Planck’s constant. Planck, a thoroughgoing conservative, had no taste for pursuing the radical consequences of his radiation formula. Someone else did: Albert Einstein. In a paper in 1905 that eventually won for him the Nobel Prize, Einstein connected Planck’s idea of limited, discontinuous energy levels to the problem of the photoelectric effect. Light shone on certain metals knocks electrons free; the effect is applied today in the solar panels that power spacecraft. But the energy of the electrons knocked free of the metal does not depend, as common sense would suggest, on the brightness of the light. It depends instead on the color of the light—on its frequency. Einstein saw a quantum condition in this odd fact. He proposed the heretical possibility that light, which years of careful scientific experiment had demonstrated to travel in waves, actually traveled in small individual packets—particles—which he called “energy quanta.” Such photons (as they are called today), he wrote, have a distinctive energy hv and they transfer most of that energy to the electrons they strike on the surface of the metal. A brighter light thus releases more electrons but not more energetic electrons; the energy of the electrons released depends on hv and so on the frequency of the light. Thus Einstein advanced Planck’s quantum idea from the status of a convenient tool for calculation to that of a possible physical fact. With these advances in understanding Bohr was able to confront the problem of the mechanical instability of Rutherford’s model of the atom. In July, at the time of the “little paper ready to show to Rutherford,” he already had his central idea. It was this: that since classical mechanics predicted that an atom like Rutherford’s, with a small, massive central nucleus surrounded by orbiting electrons, would be unstable, while in fact atoms are among the most stable of systems, classical mechanics was inadequate to describe such systems and would have to give way to a quantum approach. Planck had introduced quantum principles to save the laws of thermodynamics; Einstein had extended the quantum idea to light; Bohr now proposed to lodge quantum principles within the atom itself.
Making of the Atomic Bomb
Richard Rhodes
If you’re game to take charge of your own mobility, a fantastic “cookbook” for learning to do deep-tissue work on yourself (and a book that I highly recommend for every athlete looking to enhance mobility) is Becoming a Supple Leopard, by physical therapist Kelly Starrett, whose excellent website is MobilityWOD.com. In the book, Kelly goes into methods for self-deep-tissue work, like pressure waves, contract and relax, banded flossing, smash and floss, paper-clipping oscillation, voodoo flossing, flexion gapping, and a ton of other highly effective techniques that can literally keep you immune from injury and require little more than a lacrosse ball or a barbell.
Beyond Training
Ben Greenfield
The Dietary Guidelines for Americans, now updated every five years, spawned the infamous food pyramid in all its counterfactual glory. The foods that formed the base of the pyramid—the foods we should eat every single day—were breads, pastas and potatoes. These were the precise foods that we had previously avoided to stay thin. For example, the American Heart Association’s 1995 pamphlet, The American Heart Association Diet: An Eating Plan for Healthy Americans, declared we should eat six or more servings of “breads, cereals, pasta and starchy vegetables (that) are low in fat and cholesterol.” To drink, “Choose . . . fruit punches, carbonated soft drinks.” Ahhh. White bread and carbonated soft drinks—the dinner of champions. Thank you, American Heart Association (AHA).
The Obesity Code
Jason Fung and Timothy Noakes
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