Wheeler, John Archibald. Geons, Black Holes & Quantum Foam: a Life in Physics 1998

13: Lise Meitner & Otto Frisch formulated the explanation of fusion in Dec. 1938, which if the Nazi physicists had not ignored it would have led them to the A‑bomb

19: Had the A‑bomb project started a year earlier, the war might have ended a year earlier.

23: most nuclei are prolate spheroids (footballs)

24: the split is best achieved if the nucleus can be deformed to a peanut‑shell shape. Orange to cucumber to peanut shell. The addition of an extra neutron excites the nucleus

28: Isotopes U235 and U238 have the same number of protons but a different number of neutrons. They differ physically but not chemically. Uranium used at Hiroshima; plutonium (which does not exist in nature but was manufactured during the 39/45 war) was used at Nagasaki

28/29: Neutrons & protons belong to a group of particles called fermions. Identicals cannot co‑exist unless they have a different spin. But neutrons & protons can co‑exist. Nuclei contain equal number (more or less) of p's & n's, but heavier nuclei have more n's (U238: 92p, 146n) because p's repel each other electrically but n's do not. After U238, nuclei are too unstable. Energy is released by fusion of light nuclei, or fission of heavier

30: nuclei prefer an even number of n's or p's

45, n.2: Neutrino: no charge and little mass [a particle without mass is possible ‑ anti‑neutrinos [60,n.]

56: Barn [from side of a barn]: square with sides 1 millionth of one millionth of a centimeter. A neutron is smaller than a nucleus but can be enlarged because of its wave nature

89: anti‑matter ‑ positron

100: the helium atom with two electrons is much more complicated than the hydrogen atom with one. Scattering = bouncing off [even through] plus absorption: dispersion relation is the proportion of scattering: absorption

134: cosmic rays: mesons (between electron & proton). There are several, but mainly two kinds: pions which decay into muons which hit the earth

136: gamma ray: high energy photon

137: a nucleus behaves like a droplet

148: Problems worthy of attack / Show their worth by hitting back (Piet Hein).

There is an infinite jumble of virtual particles

153: That he is not religious but church‑going

166/7: Events happeninng before the cause: time running backwards, but prevented because the infinite number of backwards & forwards cancels out

169: Harry Smythe (his chairman at Princeton): most particles of cosmic rays are protons (hydrogen nuclei), some are of heavier elements. Hitting the atmosphere, they create particles. The most common ‑ pions ‑ are positive, negative, or neutral. Neutral goes nowhere. Positive / negative decay produces muons or neutrinos. Positive muon: 1 positron + 2 neutrinos. Negative muon: 1 electron + 2 neutrinos. If captured by n atom, it descends to lowest energy state ["orbit"] (Chang radiation). If absorbed by the nucleus, proton is transformed into a neutron and a neutrino is emitted. Pion, neutron, & proton (strongly interacting particles) are composed of quarks

174: Jayme Tiomno, chased by the Brazilian military in 1973 went to the Pontifical U in Rome

178: Muon, having a strong family resemblance to the electron, each having a companion neutrino & belonging to the family of leptons ["light" or "small"]. Muon is 200x heavier than the electron. But the "tau" with its neutrino is 3500x heavier

179: He is for the Super‑conducting Collider but allows that the energy of cosmic rays surpasses every accelerator by a large margin

185: the pre‑print is the principal means of communication. The published paper is a historical record. That nucleons move like gas molecules in the nucleus.

218: Lyman Spitzer's figure‑8 donut. The Russians had the same idea, but their Tokamak was more robust than Spitzer's Stellarator

228: in beginning his work on relativity he was "trying to get behind the mathematical formalism that had dominated the theory for decades, looking for real tangible physics"

229: the collapse of a massive star ‑ to a "singularity" ‑ a geometric point of infinite density ("black hole"). Near a proton, the electric field becomes stronger & stronger, the closer you get to the proton. If it were a true point, the field would become infinitely strong when you reach the proton. But it doesn't; the proton has a structure. The field is merely very large, not infinite.

230: From space & time, the special theory of relativity created space/time.[or confirmed it?]

231: John Philoponus demonstrated equal acceleration in 517 AD, a millennium before Galileo.

232: After we have pushed the the quantum theory in every extreme direction we can think of ... we will likely find some strange new ways in which the theory is valid before we find out where it is not valid.

235: The 3rd law: every action has a re‑action equal in force, opposite in direction. We pull the Earth to us equally as the Earth pulls us to it.

236: A gravitating body made entirely of electromagnetic fields: (G‑ravity; E‑ lectromagnetric + ON = GEON

237: A period ‑ . ‑ is 1 million atoms across; an atom is 100,000 protons across. (A period ‑.‑ is 100,000 million [100 billion] protons across)

251: New theories reduce to old in suitable domains

262: My religious convictions, which center on guides to living, guides to civilized intercourse among humans. The deep questions I wrestle with belong to science as I define it, not to religion

287: [On his work for Convair]: Convair executives were happy to make limited nuclear weapons,

but did not like to be thought of as "merchants of death".

287: How come the quantum? How come the universe? How come existence? These are questions that should fall ‑ that will fall ‑ within physics and will be answered as matters of science, not of philosophy or theology or speculation. [How easily scientists become the Village Atheist].