Energy and Human Ambitions on a Finite Planet, 2021a

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mole
is a number of atoms or molecules, tuned so that one mole of the carbon-12 isotope is exactly
12.000 grams. It takes 6.022 × 10 23 atoms for this to happen, which is called Avogadro’s number.
78, 83, 375, 376, 378, 422, 432
negative feedback
involves a reaction to some stimulus in the direction opposite the stimulus, performing a
corrective action <strong>and</strong> leading to stability. Systems in equilibrium must have negative feedback
keeping them there. 33, 123, 147, 428, 433
neo-classical economics
is the prevailing economic regime practiced today, driven by supply <strong>and</strong> dem<strong>and</strong>, fueled by
growth, market investment, <strong>and</strong> focus on micro-economics <strong>and</strong> macro-economics. 323, 427
neutrino
is a fundamental particle associated with the weak nuclear force that has almost no mass, travels
near the speed of light, <strong>and</strong> interacts so weakly with matter that it could pass through light-years
of rock before being likely to hit anything. Neutrinos from the sun stream through our bodies
constantly, day <strong>and</strong> night, since Earth is transparent to them. 243, 244, 438
neutron
is one of two basic building blocks of atomic nuclei, the other being the proton. Neutrons have
no electric charge, <strong>and</strong> a mass of 939.565 MeV, or 1.008665 atomic mass unit (a.m.u.). Neutrons
are made up of three quarks: 1 up <strong>and</strong> 2 down. 240, 243, 244, 255, 299, 375, 376, 395, 422–426,
428, 431–433, 435, 437, 438
Newton
(N) is the SI unit of force, <strong>and</strong> is equivalent to kg · m/s 2 . 68, 371, 431, 438
nuclear binding energy
is the energy associated with the strong nuclear force that holds a nucleus together against
charge repulsion. Typical levels are 8 MeV per nucleon. 247, 248
nuclear energy
derives from reconfiguring the nuclei of atoms, releasing tremendous thermal energy that can
be harnessed in a heat engine. 103, 104, 239
nucleon
is either of the two building blocks of a nucleus, meaning that it is either a proton or a neutron.
240, 247, 248, 251, 376, 432, 433, 437
nucleus
is at the center of an atom, composed of protons <strong>and</strong> neutrons <strong>and</strong> spanning ∼ 10 −15 m. The vast
majority (99.97%) of an atom’s mass is in the positively charged nucleus, which attracts a cloud
of negative-charge electrons to complete the neutral atom. 239, 375, 376, 422, 423, 425–429,
431–433, 435, 437
nuclide
is any bound arrangement of protons <strong>and</strong> neutrons. Every nucleus of every isotope is one of the
12
possible nuclides, designated, for instance as C12, C-12, or C. 240, 242, 243, 424, 428, 431, 435
overshoot
occurs when the negative feedback in a system is delayed. After surpassing the equilibrium,
oscillation may ensue. 36
parts per million
(ppm) is a unit used to measure small contributions. One ppm is 0.0001%. 61, 139, 141, 434
© 2021 T. W. Murphy, Jr.; Creative Commons Attribution-NonCommercial 4.0 International Lic.; Freely available at:
https://escholarship.org/uc/energy_ambitions.