The Science Book

A PARADIGM SHIFT 239 more limited in extent argued that the spirals might be suns or solar systems in the process of formation, ...

240 EDWIN HUBBLE universe—if you could figure out the star’s absolute magnitude from its variability period, then the star’s dis ...

A PARADIGM SHIFT 241 Doppler effect (a change in the wavelength of light due to relative motion between source and observer), an ...

242 THE RADIUS OF SPACE BEGAN AT ZERO GEORGES LEMAÎTRE (1894–1966) T he idea that the universe began with a Big Bang, expanding ...

243 See also: Isaac Newton 62–69 ■ Albert Einstein 214–21 ■ Edwin Hubble 236–41 ■ Fred Hoyle 270 neither expanding nor contracti ...

244 without end or beginning, and the prospect of a distinct point of origin (especially when proposed by a Catholic priest) was ...

245 universe must be essentially uniform in both time and space; but if it originated 10–20 billion years ago, as the Big Bang t ...

246 EVERY PARTICLE OF MATTER HAS AN ANTIMATTER COUNTERPART PAUL DIRAC (1902–1984) IN CONTEXT BRANCH Physics BEFORE 1925 Werner H ...

247 See also: James Clerk Maxwell 180–85 ■ Albert Einstein 214–21 ■ Erwin Schrödinger 226–33 ■ Werner Heisenberg 234–35 ■ Richar ...

248 See also: John Michell 88–89 ■ Albert Einstein 214–21 ■ Paul Dirac 246–47 ■ Fritz Zwicky 250–51 ■ Stephen Hawking 314 T he d ...

249 See also: Charles Darwin 142–49 ■ Gregor Mendel 166–71 ■ Thomas Hunt Morgan 224–25 A mong the first to conduct scientific ex ...

250 95 PERCENT OF THE UNIVERSE IS MISSING FRITZ ZWICKY (1898–1974) IN CONTEXT BRANCH Physics and cosmology BEFORE 1923 Edwin Hub ...

surprise, his results suggested that the cluster contained about 400 times more mass than that suggested by the combined light o ...

252 A UNIVERSAL COMPUTING MACHINE ALAN TURING (1912–1954) IN CONTEXT BRANCH Computer science BEFORE 1906 US electrical engineer ...

theoretical—an exercise in logic. He was interested in reducing a numbers task to its simplest, most basic, automatic form. The ...

THE NATURE OF THE CHEMICAL BOND LINUS PAULING (1901–1994) ...

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256 LINUS PAULING I n the late 1920s and early 1930s, in a series of landmark papers, American chemist Linus Pauling figured out ...

A PARADIGM SHIFT 257 bonding. Bonds could either be strong “sigma” bonds, in which orbitals overlap head-on, or weaker, more dif ...

258 LINUS PAULING with the structure of carbon dioxide (CO 2 ), where the sp hybrids each form a sigma bond with the oxygen, and ...