four colour theorem

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The Golden Ticket: P, NP, and the Search for the Impossible by Lance Fortnow

Alan Turing: On Computable Numbers, with an Application to the Entscheidungsproblem, Albert Einstein, Andrew Wiles, Claude Shannon: information theory, cloud computing, complexity theory, Donald Knuth, Erdős number, four colour theorem, Gerolamo Cardano, Isaac Newton, James Webb Space Telescope, Johannes Kepler, John von Neumann, Large Hadron Collider, linear programming, new economy, NP-complete, Occam's razor, P = NP, Paul Erdős, quantum cryptography, quantum entanglement, Richard Feynman, Rubik’s Cube, seminal paper, smart grid, Stephen Hawking, traveling salesman, Turing machine, Turing test, Watson beat the top human players on Jeopardy!, William of Occam

Again, you need three colors to color Tennessee, Virginia, West Virginia, Ohio, Indiana, Illinois, and Missouri, and a fourth to color Kentucky. Figure 6-2. U.S. Map. Take any map where there is some state surrounded by a ring of an odd number of other states and that map needs four colors. Here is a map of the provinces of Armenia. Figure 6-3. Armenia. There are only two provinces that lie entirely within Armenia. Kotayk’ has six neighbors and the capital province of Yerevan has four neighbors. Every state that doesn’t border the ocean has an even number of neighbors. So the heuristic says we might be able to color this map with three colors, and we can.

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Chapter 2 Nearly everything in this chapter, except the section on Occam’s razor, is a figment of my imagination meant to illustrate the unlikely world of P = NP. Chapter 3 On Milgram’s experiment, see Stanley Milgram, “The Small World Problem,” Psychology Today 2, no. 1 (1967): 60–67. The Bacon number calculation is from the Internet Movie Database. For a readable story of the four-color problem, see Robin Wilson, Four Colors Suffice: How the Map Problem Was Solved (Princeton, NJ: Princeton University Press, 2004). Chapter 4 The quotation from Cook is actually a paraphrase in modern terminology of the original quotation from his seminal paper. The original reads as follows: The theorems suggest that {tautologies} is a good candidate for an interesting set not in L*, and I feel it is worth spending considerable effort trying to prove this conjecture.

When Einstein Walked With Gödel: Excursions to the Edge of Thought by Jim Holt

Ada Lovelace, Albert Einstein, Andrew Wiles, anthropic principle, anti-communist, Arthur Eddington, Benoit Mandelbrot, Bletchley Park, Brownian motion, cellular automata, Charles Babbage, classic study, computer age, CRISPR, dark matter, David Brooks, Donald Trump, Dr. Strangelove, Eddington experiment, Edmond Halley, everywhere but in the productivity statistics, Fellow of the Royal Society, four colour theorem, Georg Cantor, George Santayana, Gregor Mendel, haute couture, heat death of the universe, Henri Poincaré, Higgs boson, inventory management, Isaac Newton, Jacquard loom, Johannes Kepler, John von Neumann, Joseph-Marie Jacquard, Large Hadron Collider, Long Term Capital Management, Louis Bachelier, luminiferous ether, Mahatma Gandhi, mandelbrot fractal, Monty Hall problem, Murray Gell-Mann, new economy, Nicholas Carr, Norbert Wiener, Norman Macrae, Paradox of Choice, Paul Erdős, Peter Singer: altruism, Plato's cave, power law, probability theory / Blaise Pascal / Pierre de Fermat, quantum entanglement, random walk, Richard Feynman, Robert Solow, Schrödinger's Cat, scientific worldview, Search for Extraterrestrial Intelligence, selection bias, Skype, stakhanovite, Stephen Hawking, Steven Pinker, Thorstein Veblen, Turing complete, Turing machine, Turing test, union organizing, Vilfredo Pareto, Von Neumann architecture, wage slave

For intellectual richness and aesthetic variety, a world of three dimensions is world enough. 10 A Comedy of Colors A century and a half ago, a student who was coloring a map of England noticed that he only needed four colors to do the job—that is, to ensure that no counties sharing a border, such as Kent and Suffolk, got the same color. This led him to guess that four colors might be sufficient for any map, real or invented. He mentioned this idle surmise to his brother. His brother in turn mentioned it to a distinguished mathematician, who, after a little experimentation to see if it looked plausible, tried and failed to prove that it was true. In the decades that followed, many other mathematicians, along with innumerable amateurs—including a great French poet, a founder of American pragmatism, and at least one bishop of London—were similarly engrossed and confounded by the map problem.

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Still, it is instructive to approach the matter by way of a glance at an actual atlas. Turn to a map of Europe, and look at the part consisting of Belgium, France, Germany, and Luxembourg. Each of these countries shares a border with the other three, so it is pretty obvious that they cannot be distinguished with fewer than four colors. You might think that four colors would be needed only when a map contains a quartet of mutually neighboring regions like this. If you do, turn to a map of the United States, and look at Nevada along with the five states that ring it (California, Oregon, Idaho, Utah, and Arizona). No four of these states are mutually neighboring, the way Belgium, France, Germany, and Luxembourg are.

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Yet the cluster as a whole cannot be distinguished with fewer than four colors, as you can easily verify. On the other hand—and this may shake your intuition a bit—Wyoming and the six states that ring it can be distinguished with a mere three colors. Some maps need four colors: that much is patent. What the four-color conjecture asserts is that there is no possible map that needs more than four colors. What would it mean to “resolve” this conjecture? There are two possibilities. Suppose—as some mathematicians have believed—the conjecture is false. Then drawing just one map that required five or more colors would clinch the matter. (In the Scientific American of April 1975, Martin Gardner published a complicated map, consisting of 110 regions, that he claimed could not be colored with fewer than five colors.

The Logician and the Engineer: How George Boole and Claude Shannon Created the Information Age by Paul J. Nahin

air gap, Alan Turing: On Computable Numbers, with an Application to the Entscheidungsproblem, Albert Einstein, Any sufficiently advanced technology is indistinguishable from magic, Charles Babbage, Claude Shannon: information theory, Computing Machinery and Intelligence, conceptual framework, Edward Thorp, Fellow of the Royal Society, finite state, four colour theorem, Georg Cantor, Grace Hopper, Isaac Newton, John von Neumann, knapsack problem, New Journalism, Pierre-Simon Laplace, reversible computing, Richard Feynman, Schrödinger's Cat, Steve Jobs, Steve Wozniak, thinkpad, Thomas Bayes, Turing machine, Turing test, V2 rocket

Since the 1976 computer-based proof that, in general, it requires four colors to color a planar map, we know that there are maps for which three colors would not be sufficient. But, nevertheless, there are particular maps for which three colors are enough. There is, alas, no efficient algorithm known that can distinguish between three-color and four-color maps, and so having a quantum computer available would be of no help. And even when a quantum algorithm is known, it may not result in a polynomial time computation. Grover’s search algorithm is such a case because, while is indeed faster than N, we know from our earlier discussion of the factoring problem that is still exponential and not polynomial.

Infinite Powers: How Calculus Reveals the Secrets of the Universe by Steven Strogatz

Albert Einstein, Asperger Syndrome, Astronomia nova, Bernie Sanders, clockwork universe, complexity theory, cosmological principle, Dava Sobel, deep learning, DeepMind, double helix, Edmond Halley, Eratosthenes, four colour theorem, fudge factor, Henri Poincaré, invention of the telescope, Isaac Newton, Islamic Golden Age, Johannes Kepler, John Harrison: Longitude, Khan Academy, Laplace demon, lone genius, music of the spheres, pattern recognition, Paul Erdős, Pierre-Simon Laplace, precision agriculture, retrograde motion, Richard Feynman, Socratic dialogue, Steve Jobs, the rule of 72, the scientific method

In parts of mathematics and science, we are already experiencing the dusk of insight. There are theorems that have been proved by computers, yet no human being can understand the proof. The theorems are correct but we have no insight into why. And at this point, the machines cannot explain themselves. Consider the famous long-standing math problem called the four-color map theorem. It says that under certain reasonable constraints, any map of contiguous countries can always be colored with just four colors such that no two neighboring countries are colored the same. (Look at a typical map of Europe or Africa or any other continent besides Australia and you’ll see what I mean.)

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See formulas Eratosthenes, 42, 49 Erdős, Paul, 294 Euclid, 32, 90–91, 188, 236 Eudoxus, method of exhaustion used by, 32 exponential functions, 127–28 exponential growth and decay, 137–39, 220–24, 251 F facial surgery, 53–56, 56 falling bodies, 66–69 Faraday, Michael, x–xi FBI fingerprinting technology, 107–13, 257 feedback loop, 138 Ferguson, Samuel, 294 Fermat, Pierre de analytic geometry, 101–3 background, 100 contributions of, 93, 120–21, 194 Descartes rivalry, 98–99 FBI fingerprinting technology, 107–13 optimization, 103–7 principle of least time, 113–18, 319n118 tangents, 118–20 xy plane, 96–97 Feynman, Richard, vii, viii–ix, 295–97 Finding Nemo (movie), 50 fingerprints database, 107–13 finite decimals, 10 fluxions, 184 foci (focal points), 81–82 force, 230–31, 252, 258 formulas circle, area of, 7, 33 force and motion, 230–31, 252, 258 functions of one variable, 124 fundamental theorem, 179–80, 211 HIV decay, 221–22 Kepler’s third law, 85 parabolic segment, 38, 39 pi, bounds of, 32 power series (area of circular segment), 190, 191 sine waves, derivative of, 258 velocity, 173 forward problem, 144–46, 175, 179–80 four-color map theorem, 293 Fourier, Jean Baptiste Joseph applications of work, 256 Fourier analysis, 267 heat flow, 249–52 string theory, 252–56 Fourier analysis, 267 Fourier series, 254 fourth dimension, 287–91 frequencies, 254, 256, 259–60 friction, 69–70, 232–33, 245 Fuller, Brock, 275 functions applications of, 125–26 exponential functions, 127–28 exponential growth and decay, 137–39 linear functions, 146–49 logarithms, 131–34 natural base (e), 134–37 nonlinear equations, 149–54 power functions, 126–27, 182 scientific notation, 128–31 three central problems of, 144–46 xy plane, 124–25 See also derivatives fundamental theorem backward problem, 180–85 constant acceleration, 172–75 differentials, 209–11 discovery of, 168–69 equation for, 179–80, 211 Leibniz’s approach to, 211–18, 213 local vs global operations, 185–86 meaning of, 179–80 motion and change, 169–72 Newton on, 182, 193–94 “paint-roller” proof, 175–79, 178 future directions, 271–94 chaos, 281–82 computers, 285–87 determinism, 277–79 dimensions, four or more, 287–91 DNA, 273–76 nonlinearity, 279–80 Poincaré’s vector fields, 282–84 predictions, 273 radar, 284–85 G Galilei, Galileo, 64–76 background, 64 constant acceleration, 173 contributions of, 59–60, 86–88 Discourses and Mathematical Demonstrations Concerning Two New Sciences, 65 falling bodies, 66–69 functions of one variable, 124 house arrest, 65–66 ideal conditions, 69–71 vs Kepler, 85–86 observations with telescope, 65 pendulums, 71–77 power functions, 126–27 principle of inertia, 231 religious beliefs, 65 Two New Sciences, 68, 70, 71–72 Galilei, Virginia (Maria Celeste), 64, 65 Gamba, Marina, 64 Gauss, Carl Friedrich, 261 geometric series, 39 geometry algebra, merge with, 93–96, 98 analytic geometry, 101–3 area of a circle, 4–8 birthplace of, 90 harmony and, 49 Kepler on, 60, 79–80, 82 in Nature, 70 Plato on, 60 Geometry (Descartes), 119 Geri’s Game (movie), 51–52, 52 Germain, Sophie, 260, 261–62 Gilbert, William, 87 Glenn, John, 237–38 global operations.

A Mathematician Plays the Stock Market by John Allen Paulos

Alan Greenspan, AOL-Time Warner, Benoit Mandelbrot, Black-Scholes formula, book value, Brownian motion, business climate, business cycle, butter production in bangladesh, butterfly effect, capital asset pricing model, confounding variable, correlation coefficient, correlation does not imply causation, Daniel Kahneman / Amos Tversky, diversified portfolio, dogs of the Dow, Donald Trump, double entry bookkeeping, Elliott wave, endowment effect, equity risk premium, Erdős number, Eugene Fama: efficient market hypothesis, four colour theorem, George Gilder, global village, greed is good, index fund, intangible asset, invisible hand, Isaac Newton, it's over 9,000, John Bogle, John Nash: game theory, Larry Ellison, Long Term Capital Management, loss aversion, Louis Bachelier, mandelbrot fractal, margin call, mental accounting, Myron Scholes, Nash equilibrium, Network effects, passive investing, Paul Erdős, Paul Samuelson, Plato's cave, Ponzi scheme, power law, price anchoring, Ralph Nelson Elliott, random walk, Reminiscences of a Stock Operator, Richard Thaler, risk free rate, Robert Shiller, short selling, six sigma, Stephen Hawking, stocks for the long run, survivorship bias, transaction costs, two and twenty, ultimatum game, UUNET, Vanguard fund, Yogi Berra

Given the payoffs and human psychology, the most likely outcome is for both to confess; the best outcome for the pair as a pair is for both to remain silent; the best outcome for each prisoner as an individual is to confess and have one’s partner remain silent. The charm of the dilemma has nothing to do with any interest one might have in prisoners’ rights. (In fact, it has about as much relevance to criminal justice as the four-color-map theorem has to geography.) Rather, it provides the logical skeleton for many situations we face in everyday life. Whether we’re negotiators in business, spouses in a marriage, or nations in a dispute, our choices can often be phrased in terms of the prisoner’s dilemma. If both (all) parties pursue their own interests exclusively and do not cooperate, the outcome is worse for both (all) of them; yet in any given situation, any given party is better off not cooperating.

The Lies That Bind: Rethinking Identity by Kwame Anthony Appiah

affirmative action, assortative mating, Boris Johnson, British Empire, classic study, Donald Trump, Downton Abbey, European colonialism, Ferguson, Missouri, four colour theorem, full employment, Great Leap Forward, Gregor Mendel, illegal immigration, Isaac Newton, longitudinal study, luminiferous ether, Mahatma Gandhi, mass immigration, means of production, meritocracy, Parler "social media", precariat, Scramble for Africa, selection bias, Suez canal 1869, transatlantic slave trade, W. E. B. Du Bois, zero-sum game

(The elite members of a football team have an advantage in honor, as well as in earnings, over its benchwarmers, but class isn’t the right way to describe the arrangement.) Heritability is part of the picture; so is the prospect of upward or downward mobility. The connection between class and wealth, though complex, is indissoluble. You can start to see why class became the four-color-map problem of the social sciences. The more variables we try to account for, the harder it is to solve. Indeed, given the uncertainties about precisely how class identities might be defined or demarcated, a number of sociologists have, over the decades, sought to banish the term—to abolish “class,” if not class.

Journey to the Edge of Reason: The Life of Kurt Gödel by Stephen Budiansky

Abraham Wald, Albert Einstein, anti-communist, business cycle, Douglas Hofstadter, fear of failure, Fellow of the Royal Society, four colour theorem, Georg Cantor, Gregor Mendel, Gödel, Escher, Bach, John von Neumann, laissez-faire capitalism, P = NP, P vs NP, Paul Erdős, rent control, scientific worldview, the scientific method, Thorstein Veblen, Turing machine, urban planning

An attractive young schoolteacher from Venice, California, sent a snapshot of herself posing in front of a large-format reproduction of the Eisenstaedt portrait posted on the wall of her classroom, which she explained in an accompanying note “serves two purposes: it intimidates the students, and it inspires me.” An irrigation engineer in India and other self-taught amateurs sent him their supposed solutions to the four-color map problem, crackpot philosophical treatises, and (from an employee of an air-conditioning company) a proof that the Second Law of Thermodynamics implies the negation of the Axiom of Choice. Gerald Sacks thought Gödel was far too kind to all the cranks who would call up to talk to him. “He was an extremely courteous man,” Sacks observed.

In Pursuit of the Traveling Salesman: Mathematics at the Limits of Computation by William J. Cook

Bletchley Park, complexity theory, computer age, Computer Numeric Control, financial engineering, four colour theorem, index card, John von Neumann, linear programming, NP-complete, P = NP, p-value, RAND corporation, Richard Feynman, traveling salesman, Turing machine

The same trick allows us to two-color the regions lying outside of the Hamiltonian circuit, yielding altogether a four-coloring of the map. In the example, the inner regions are colored dark yellow and light yellow, and the outer regions are colored dark blue and light blue. Tait knew that not all maps have Hamiltonian circuits through their borders (the map of the continental United States is a ready example), but available tricks allowed the four-color problem to be restricted to maps such that each vertex of the border graph meets exactly three edges. Furthermore, the border graph could be assumed to be three-connected, that is, it is impossible to break the graph into two parts by deleting one or Origins of the Problem two vertices.

How the Mind Works by Steven Pinker

affirmative action, agricultural Revolution, Alfred Russel Wallace, Apple Newton, backpropagation, Buckminster Fuller, cognitive dissonance, Columbine, combinatorial explosion, complexity theory, computer age, computer vision, Computing Machinery and Intelligence, Daniel Kahneman / Amos Tversky, delayed gratification, disinformation, double helix, Dr. Strangelove, experimental subject, feminist movement, four colour theorem, Geoffrey Hinton, Gordon Gekko, Great Leap Forward, greed is good, Gregor Mendel, hedonic treadmill, Henri Poincaré, Herman Kahn, income per capita, information retrieval, invention of agriculture, invention of the wheel, Johannes Kepler, John von Neumann, lake wobegon effect, language acquisition, lateral thinking, Linda problem, Machine translation of "The spirit is willing, but the flesh is weak." to Russian and back, Mikhail Gorbachev, Murray Gell-Mann, mutually assured destruction, Necker cube, out of africa, Parents Music Resource Center, pattern recognition, phenotype, Plato's cave, plutocrats, random walk, Richard Feynman, Ronald Reagan, Rubik’s Cube, Saturday Night Live, scientific worldview, Search for Extraterrestrial Intelligence, sexual politics, social intelligence, Steven Pinker, Stuart Kauffman, tacit knowledge, theory of mind, Thorstein Veblen, Tipper Gore, Turing machine, urban decay, Yogi Berra

Something must have impelled him to explore strange new worlds, to seek out new civilizations, and to boldly go where no man had gone before. Presumably it was intellectual curiosity, a drive to set and solve problems, and solidarity with allies—emotions all. And what would Spock have done when faced with a predator or an invading Klingon? Do a headstand? Prove the four-color map theorem? Presumably a part of his brain quickly mobilized his faculties to scope out how to flee and to take steps to avoid the vulnerable predicament in the future. That is, he had fear. Spock may not have been impulsive or demonstrative, but he must have had drives that impelled him to deploy his intellect in pursuit of certain goals rather than others.

Under the Loving Care of the Fatherly Leader: North Korea and the Kim Dynasty by Bradley K. Martin

anti-communist, Asian financial crisis, colonial rule, cuban missile crisis, Deng Xiaoping, Dr. Strangelove, failed state, Ford Model T, four colour theorem, Great Leap Forward, guns versus butter model, illegal immigration, informal economy, kremlinology, land reform, means of production, Mikhail Gorbachev, military-industrial complex, Neil Armstrong, Potemkin village, profit motive, RAND corporation, Ronald Reagan, Shenzhen special economic zone , special economic zone, stakhanovite, two and twenty, UNCLOS, upwardly mobile, uranium enrichment, women in the workforce, zero-sum game

Rajin and Sonbong port officials planned to expand cargo capacity from six million to 50 million tons a year in two stages—and also planned to build a brand new port in the area with annual capacity of another 50 million tons. Unlike some nearby Russian ports, they boasted, the North Korean ports didn’t freeze up in winter. A slick brochure complete with four-color maps projected that the population of 131,000 North Koreans living in the vicinity of the two ports would grow into a modern industrial city of a million people. Conceivably a purely North Korean economic zone could work, if South Korean, Japanese or other foreign interests invested in factories there.

Prime Obsession:: Bernhard Riemann and the Greatest Unsolved Problem in Mathematics by John Derbyshire

Albert Einstein, Andrew Wiles, Bletchley Park, Charles Babbage, Colonization of Mars, Eratosthenes, Ernest Rutherford, four colour theorem, Georg Cantor, Henri Poincaré, Isaac Newton, John Conway, John von Neumann, Paul Erdős, Richard Feynman, Turing machine, Turing test

Infinite Ascent: A Short History of Mathematics by David Berlinski

Alan Turing: On Computable Numbers, with an Application to the Entscheidungsproblem, Albert Einstein, Andrew Wiles, Benoit Mandelbrot, Douglas Hofstadter, Eratosthenes, four colour theorem, Georg Cantor, Gödel, Escher, Bach, Henri Poincaré, Isaac Newton, John von Neumann, Murray Gell-Mann, Stephen Hawking, Turing machine, William of Occam

Chasing New Horizons: Inside the Epic First Mission to Pluto by Alan Stern, David Grinspoon

Apollo 11, Apollo 13, crowdsourcing, Dava Sobel, delayed gratification, four colour theorem, Kuiper Belt, Mars Rover, Neil Armstrong, orbital mechanics / astrodynamics, Pluto: dwarf planet, space junk, SpaceShipOne

Its name came from a silly joke referring to the old Honeymooners’ TV show characters, Ralph and Alice Kramden. Whereas Alice’s objective was primarily to study Pluto’s atmosphere, Ralph’s objective was to map and also determine the composition of Pluto’s surface. The size of a hat box, Ralph contains two black-and-white cameras, four color filter cameras, and an “infrared mapping spectrometer” to map surface compositions. Ralph can see colors that are redder than any red humans can see, at wavelengths which are called infrared, where minerals and ices have characteristic spectral features that can be used to reveal the surface materials at any given location in Ralph’s field of view.

Everything for Everyone: The Radical Tradition That Is Shaping the Next Economy by Nathan Schneider

1960s counterculture, Aaron Swartz, Adam Curtis, Affordable Care Act / Obamacare, Airbnb, altcoin, Amazon Mechanical Turk, antiwork, back-to-the-land, basic income, Berlin Wall, Bernie Sanders, bitcoin, Black Lives Matter, blockchain, Brewster Kahle, Burning Man, Capital in the Twenty-First Century by Thomas Piketty, carbon footprint, carbon tax, Clayton Christensen, collaborative economy, collective bargaining, commons-based peer production, Community Supported Agriculture, corporate governance, creative destruction, crowdsourcing, cryptocurrency, Debian, degrowth, disruptive innovation, do-ocracy, Donald Knuth, Donald Trump, Edward Snowden, Elon Musk, emotional labour, Ethereum, ethereum blockchain, Evgeny Morozov, Fairphone, Food sovereignty, four colour theorem, future of work, Gabriella Coleman, gentrification, gig economy, Google bus, holacracy, hydraulic fracturing, initial coin offering, intentional community, Internet Archive, Jeff Bezos, Jeremy Corbyn, jimmy wales, John Perry Barlow, joint-stock company, Joseph Schumpeter, Julian Assange, Kevin Roose, Kickstarter, low interest rates, Lyft, M-Pesa, Marc Andreessen, Mark Zuckerberg, Marshall McLuhan, mass immigration, means of production, Money creation, multi-sided market, Murray Bookchin, new economy, offshore financial centre, old-boy network, Peter H. Diamandis: Planetary Resources, Pier Paolo Pasolini, post-work, precariat, premature optimization, pre–internet, profit motive, race to the bottom, Richard Florida, Richard Stallman, ride hailing / ride sharing, Rutger Bregman, Salesforce, Sam Altman, Satoshi Nakamoto, self-driving car, shareholder value, sharing economy, Silicon Valley, Slavoj Žižek, smart contracts, Steve Bannon, Steve Jobs, Steve Wozniak, Stewart Brand, surveillance capitalism, tech worker, TED Talk, transaction costs, Turing test, Uber and Lyft, uber lyft, underbanked, undersea cable, universal basic income, Upton Sinclair, Vanguard fund, Vitalik Buterin, W. E. B. Du Bois, white flight, Whole Earth Catalog, WikiLeaks, women in the workforce, working poor, workplace surveillance , Y Combinator, Y2K, Zipcar

Data Action: Using Data for Public Good by Sarah Williams

affirmative action, Amazon Mechanical Turk, Andrei Shleifer, augmented reality, autonomous vehicles, Brexit referendum, Cambridge Analytica, Charles Babbage, City Beautiful movement, commoditize, coronavirus, COVID-19, crowdsourcing, data acquisition, data is the new oil, data philanthropy, data science, digital divide, digital twin, Donald Trump, driverless car, Edward Glaeser, fake news, four colour theorem, global village, Google Earth, informal economy, Internet of things, Jane Jacobs, John Snow's cholera map, Kibera, Lewis Mumford, Marshall McLuhan, mass immigration, mass incarceration, megacity, military-industrial complex, Minecraft, neoliberal agenda, New Urbanism, Norbert Wiener, nowcasting, oil shale / tar sands, openstreetmap, place-making, precautionary principle, RAND corporation, ride hailing / ride sharing, selection bias, self-driving car, sentiment analysis, Sidewalk Labs, smart cities, Smart Cities: Big Data, Civic Hackers, and the Quest for a New Utopia, Steven Levy, the built environment, The Chicago School, The Death and Life of Great American Cities, transatlantic slave trade, Uber for X, upwardly mobile, urban planning, urban renewal, W. E. B. Du Bois, Works Progress Administration

Community groups in Chicago's Austin neighborhood in the 1960s coined the term “redlining” in reference to the red lines that lenders and insurance providers admitted to drawing around the areas where they would not provide mortgages.63 Bartholomew's zoning maps provided the impetus for disinvestment in African American communities that the Home Owners’ Loan Corporation (HOLC) maps (1933–1936) continued (figure 1.24). HOLC maps identified mortgage risk in 239 cities across the United States, using four categories. The highest risk—the red color on HOLC maps—identified African American communities, areas with so-called incongruent uses and poor housing stock. 1.24 Home Owners’ Loan Corporation maps of Chicago, showing the inner-city African American neighborhoods in red. Source: Form-Based Codes Institute, “Zoning for Equity: Raising All Boats,” 2019, https://formbasedcodes.org/blog/zoning-equity-raising-boats/.

The Great Displacement: Climate Change and the Next American Migration by Jake Bittle

augmented reality, clean water, climate anxiety, climate change refugee, coronavirus, cotton gin, COVID-19, decarbonisation, digital map, Donald Trump, energy transition, four colour theorem, gentrification, Google Earth, housing crisis, illegal immigration, immigration reform, longitudinal study, McMansion, off-the-grid, oil shock, place-making, Ralph Waldo Emerson, risk tolerance, smart cities, tail risk, Tipper Gore, Tragedy of the Commons, urban planning, urban renewal, urban sprawl, white flight, Yom Kippur War, young professional

Most houses in the communities are already elevated, but if residents didn’t have pickup trucks with high suspension, it wasn’t safe for them to drive out to the main highway. When I drove through Stillwright Point a year later, the county had placed flood barriers—they looked like long orange burritos—to protect the streets from flooding, but the tides had crept in anyhow, covering several laneways with three or four inches of khaki-colored water. According to Haag’s map, another foot of sea-level rise would mean almost year-round inundation. One resident from Stillwright Point told me that residents in his neighborhood have already begun to jockey with residents from Twin Lakes over which community will be the first to get its roads raised.