Cesare Marchetti: Marchetti’s constant

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Rush Hour by Iain Gately

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Albert Einstein, autonomous vehicles, Beeching cuts, blue-collar work, British Empire, business intelligence, business process, business process outsourcing, call centre, car-free, Cesare Marchetti: Marchetti’s constant, Clapham omnibus, cognitive dissonance, congestion charging, connected car, corporate raider, DARPA: Urban Challenge, Dean Kamen, decarbonisation, Deng Xiaoping, Detroit bankruptcy, don't be evil, Elon Musk, extreme commuting, Google bus, Henri Poincaré, Hyperloop, Jeff Bezos, low skilled workers, Marchetti’s constant, postnationalism / post nation state, Ralph Waldo Emerson, remote working, self-driving car, Silicon Valley, stakhanovite, Steve Jobs, telepresence, Tesla Model S, urban planning, éminence grise

Although they work shorter hours, they spend an hour or so each day on the hoof – or about the same as the average OECD commuter. The similarity in daily travel time between such radically different lifestyles inspired Cesare Marchetti, the Venetian theoretical physicist, to suggest that there was a ‘quintessential unity of travelling instincts around the world’ and that this unity resulted in a fixed ‘travel time budget’ that he named after himself as Marchetti’s Constant. He tested his theory against a variety of cultures past and present and decided that it has shaped our behaviour since the dawn of history. The territory associated with ancient Greek villages, for instance, whose inhabitants went about on foot, was about twenty square kilometres, which was about as much as they could manage within their travel time budget, and this pedestrian limit continued to restrict the size of towns and settlements until the Industrial Revolution.

Although the French government promised to spend 400 million euros on upgrading the network in 2013, this was still less than half the sum budgeted for TGV lines. It may be, however, that HS2 and its continental equivalents aren’t being ambitious enough. If displacing aeroplanes is the aim, then why not build an elevated Maglev, such as was imagined by Cesare Marchetti in 1994, running from the Channel tunnel to Aberdeen? It’s only 438 miles, which a Maglev travelling at conservative speeds, and stopping at London Heathrow, Birmingham, Manchester and Edinburgh en route, could manage within an hour. With a few feeder lines it might extend the ‘commuter-shed’ of all these places for dozens of miles in every direction.

A Fixed-Effects Analysis of Panel Data’, Psychological Science, published online 23 April 2013, DOI:10.1177/ 0956797612464659. 229 For ‘Stall Luft’, see: http://metro.co.uk/2011/03/ 04/cow-fart-cans-offers-authentic-smell-of-countryside-642451/. 230 ‘free up sufficient equity to fund’, Sophie Chick, Savills, ‘Value in the commuter zone’, 19 February 2013: http://www.savills.co.uk/research_articles/141560/144657-0. See also Insights, Commuting Trends Review, Autumn 2010, Blue Door Media Ltd., for Savills. 231 ‘quintessential unity of travelling instincts around the world’, Cesare Marchetti, ‘Anthropological Invariants in Travel Behaviour’, Technological Forecasting and Social Change, vol. 47, no. 1, 1994, p. 88. 232 For the Hadza tribe of Tanzania, see Michael Finkel, ‘The Hadza’, National Geographic magazine, December 2009. http://ngm.national geographic.com/print/2009/ 12/hadza/ finkel-text. 234 For ‘it’s worth it to me to come home’, Dave Givens talking to Andrea Seabrook of NPR, 14 June 2008, see: http://seattletimes.com/html/nationworld/2002970862_commute04.html. 234 For ‘better option’, see: http://www.bbc.co.uk/news/magazine-25551393. 236 For ‘more than half of America’s schoolchildren’, see: http://www.americanschool buscouncil.org/issues/environmental-benefits.


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Aerotropolis by John D. Kasarda, Greg Lindsay

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3D printing, air freight, airline deregulation, airport security, Akira Okazaki, Asian financial crisis, back-to-the-land, barriers to entry, Berlin Wall, big-box store, blood diamonds, borderless world, British Empire, call centre, carbon footprint, Cesare Marchetti: Marchetti’s constant, Clayton Christensen, cleantech, cognitive dissonance, commoditize, conceptual framework, credit crunch, David Brooks, David Ricardo: comparative advantage, Deng Xiaoping, deskilling, digital map, edge city, Edward Glaeser, failed state, food miles, Ford paid five dollars a day, Frank Gehry, fudge factor, full employment, future of work, Geoffrey West, Santa Fe Institute, George Gilder, global supply chain, global village, gravity well, Haber-Bosch Process, Hernando de Soto, hive mind, if you build it, they will come, illegal immigration, inflight wifi, intangible asset, interchangeable parts, Intergovernmental Panel on Climate Change (IPCC), intermodal, invention of the telephone, inventory management, invisible hand, Jane Jacobs, Jeff Bezos, Kangaroo Route, knowledge worker, kremlinology, labour mobility, Marchetti’s constant, Marshall McLuhan, Masdar, mass immigration, McMansion, megacity, Menlo Park, microcredit, Network effects, New Economic Geography, new economy, New Urbanism, oil shale / tar sands, oil shock, peak oil, Pearl River Delta, Peter Thiel, pets.com, pink-collar, pre–internet, RFID, Richard Florida, Ronald Coase, Ronald Reagan, Rubik’s Cube, savings glut, Seaside, Florida, Shenzhen was a fishing village, Silicon Valley, Silicon Valley startup, Skype, smart cities, smart grid, South China Sea, South Sea Bubble, sovereign wealth fund, special economic zone, spice trade, spinning jenny, stem cell, Steve Jobs, supply-chain management, sustainable-tourism, telepresence, the built environment, The Chicago School, The Death and Life of Great American Cities, The Nature of the Firm, thinkpad, Thomas L Friedman, Thomas Malthus, Tony Hsieh, trade route, transcontinental railway, transit-oriented development, traveling salesman, trickle-down economics, upwardly mobile, urban planning, urban renewal, urban sprawl, walkable city, white flight, white picket fence, Yogi Berra, zero-sum game

Melvin Webber’s concept of “community without propinquity” is best explained in his essay “Order in Diversity: Community Without Propinquity,” which was collected in Cities and Space: The Future Use of Urban Space. His quotation is lifted from the same. Marchetti’s Constant is derived from Cesare Marchetti’s paper “Anthropological Invariants in Travel Behavior” (Technological Forecasting and Social Change, vol. 47, 1994). His maglev thought experiment appears in “The Evolution of Transport,” by Jesse H. Ausubel and Cesare Marchetti (Industrial Physicist, April/May 2001). The Future Forum report was published by the British travel firm Thomson in 2006. The University of California sociologist Claude Fischer wrote about Americans’ itinerancy (or increasing lack thereof) in “Ever More Rooted Americans” (City & Community, June 2002).

When he finished Peachtree Center in 1976, the result was a hermetically sealed “Center” central to nothing except its clones elsewhere. He had built the urban equivalent of a hub, profitable and infinitely repeatable anywhere. And with that, his LEGO-block approach became the reigning vernacular in Airworld’s peculiar geography of nowhere. Kasarda’s Law and Marchetti’s Constant It wasn’t supposed to be this way. Technology was going to ground us by linking and shrinking the world, and in doing so set us free. The world would flatten. Road warriors would beat their platinum medallions into plowshares. It hasn’t happened. For twenty years, we’ve heard how e-mail and videoconferencing— relabeled “telepresence”—would eliminate the need for cross-country meetings.

But as horse trams came along, followed by electric trams, then subways, and finally cars, the city’s periphery raced away from its Enlightenment-era core. Berlin’s diameter was effectively ten times wider in 1950 than it was 150 years earlier, yet it still took only an hour to traverse. The rule has since been dubbed Marchetti’s Constant. Marchetti contended that transportation, not communications, was the “unifying principle of the world.” Ratifying Kasarda’s Law, he attested that the “so-called explosion in communication during the last 20 years did not dent transportation expansion; on the other hand, they tend to move together.”


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Scale: The Universal Laws of Growth, Innovation, Sustainability, and the Pace of Life in Organisms, Cities, Economies, and Companies by Geoffrey West

Alfred Russel Wallace, Anton Chekhov, Benoit Mandelbrot, Black Swan, British Empire, butterfly effect, carbon footprint, Cesare Marchetti: Marchetti’s constant, clean water, complexity theory, computer age, conceptual framework, continuous integration, corporate social responsibility, correlation does not imply causation, creative destruction, dark matter, Deng Xiaoping, double helix, Edward Glaeser, endogenous growth, Ernest Rutherford, first square of the chessboard, first square of the chessboard / second half of the chessboard, Frank Gehry, Geoffrey West, Santa Fe Institute, Guggenheim Bilbao, housing crisis, Index librorum prohibitorum, invention of agriculture, invention of the telephone, Isaac Newton, Jane Jacobs, Jeff Bezos, Johann Wolfgang von Goethe, John von Neumann, Kenneth Arrow, laissez-faire capitalism, life extension, Mahatma Gandhi, mandelbrot fractal, Marchetti’s constant, Masdar, megacity, Murano, Venice glass, Murray Gell-Mann, New Urbanism, Peter Thiel, profit motive, publish or perish, Ray Kurzweil, Richard Feynman, Richard Feynman, Richard Florida, Silicon Valley, smart cities, Stephen Hawking, Steve Jobs, Stewart Brand, technological singularity, The Coming Technological Singularity, The Death and Life of Great American Cities, the scientific method, too big to fail, transaction costs, urban planning, urban renewal, Vernor Vinge, Vilfredo Pareto, Von Neumann architecture, Whole Earth Catalog, Whole Earth Review, wikimedia commons, working poor

This surprising observation of the approximately one-hour invariant that communal human beings have spent traveling each day, whether they lived in ancient Rome, a medieval town, a Greek village, or twentieth-century New York, has become known as Marchetti’s constant, even though it was originally discovered by Zahavi. As a rough guide it clearly has important implications for the design and structure of cities. As planners begin to design green carless communities and as more cities ban automobiles from their centers, understanding and implementing the implied constraints of Marchetti’s constant becomes an important consideration for maintaining the functionality of the city. 4. THE INCREASING PACE OF WALKING Zahavi and Marchetti presumed that for a given mode of transportation, such as walking or driving, travel speed did not change with city size.

., 48–49 life expectancy (life span), 6, 11–12, 183–94, 457n estimated gain in, if given disease was cured, 193, 193–94 human mortality curve, 189–90, 192, 192–94, 193 human survivorship curves, 189–94, 191, 192 maximum, 6, 24, 188–94, 202–3 temperature dependence of, 175, 176, 177, 203–4 life extension, 6, 183–94, 203–7 body temperature and, 203–4 caloric restriction and, 205–7, 206 heartbeats and pace of life, 204–5 Limehouse (London), 224–26 Limits to Growth, The (Meadows), 231–32 linear thinking, 17–18, 44–45, 72, 157 links and social networks, 297–98, 298, 319–20 Liverpool, walking lanes, 335–36, 336 Living Earth Simulator, 271 Lobo, José, 274–75, 356, 364, 386 logarithms, 26, 47–48, 49 London, 222–26, 267–68 garden cities, 255 growth curve, 376 Longevity Prize, 184 Los Alamos National Laboratory, 83–84, 106, 274, 405, 434, 435 Los Angeles, 17–18, 251, 310 growth curve, 377 infrastructure networks, 252 Lösch, August, 290 Lower Manhattan Expressway, 260 LSD, 52–54 MacBook Air, 439, 445 machine learning, 443–44 macroecology, 105 magic number four, 6, 117 self-similarity and origin of, 126–30 universality and, 93–99 maintenance expenses, 391–93 Malthus, Thomas Robert, 227–30, 287, 414–15, 416, 423 Malthusians, 227–30, 414–15 mammals. See animals Manchester, England, 223–24 Mandelbrot, Benoit, 130–31, 132, 138–45, 152, 364 Mandelbrot set, 143–44 manufacturing, 211 Marchetti, Cesare, 333–35 Marchetti’s constant, 334–35 market capitalization, 379, 389–90 market share, 408–9 Marx, Karl, 228, 332 Masdar (Abu Dhabi), 256, 258, 299 Mathematical Principles of Natural Philosophy (Newton), 181 mathematics, 8 biology and, 85–86, 87 Euclidean geometry, 130–31, 141–42 matryoshka, 128 maximal Krogh radius, 160 maximum life span, 6, 188–94, 202–3 maximum size of animals, 158–63 Maxwell, James Clerk, 109, 115, 428 McCarthy, Cormac, 425 McKinsey & Company, 404, 405 McMahon, Thomas, 198 Mead, Margaret, 239 Meadows, Dennis, 231–32 measurement process, 135–41 mechanical constraints, 122, 158–63 mechanistic theory, 12, 85, 111–12, 144, 145, 182, 408 Medawar, Peter, 86 medical research, 52–55 Medical Research Council Unit (MRCU), 437 medicine, scaling in, 16, 51–57 megacities, 7, 215, 223–24, 267–68 Meier, Paul, 403 mergers and acquisitions, 33, 403–4 survivorship curves, 396–97, 399 metabolic energy emergent laws and hierarchy of life, 99–103 growth and, 165–66 metabolic rate, 13, 18–19, 124–26, 201, 234 of animals, 2, 2n, 3, 13, 18–19, 25–26, 91–92, 285–86 of average human, 88–89 of bacteria and cells, 93, 94, 96 of companies, 391–92 definition of, 13 Kleiber’s law and, 26–27, 90–93, 117, 145 in mammals, plants, and trees, 18–19, 118–22 natural selection and, 88–90, 151 scaling of, 90–91, 173 metabolic theory of ecology (MTE), 115–16, 173–78, 203–4 metabolism of cities, 371–78 energy, and entropy, 12–15 social, 13, 373–74, 415 Metabolism (architecture), 247–48 metaphysics, 179–80 Metropolitan Statistical Areas (MSAs), 356, 462n Mexico City, growth curve, 375 mice, 6, 12, 16, 52, 114 caloric restriction and survival curves, 205, 206 Milgram, Stanley, 296–97, 301–4 Milgram experiment, 301–2 Milky Way, 79 Millennium Bridge (London), 298–300 minimum size of animals, 155–58 mitochondria, 100–102, 101, 113 mobile phone data, as detector of human behavior, 337–45, 351–52, 439 modeling, 62–63 modeling theory, 35, 71–75 Modena, Italy, 249 momentum, 20–21 Moore, James, 249 mortality.

The conclusion is clear: the size of cities has to some degree been determined by the efficiency of their transportation systems for delivering people to their workplaces in not much more than half an hour’s time. Zahavi’s fascinating observations made a powerful impression on the Italian physicist Cesare Marchetti, who was a senior scientist at the International Institute for Applied Systems Analysis (IIASA) in Vienna. IIASA has been a major player in questions of global climate change, environmental impact, and economic sustainability, and this is where Marchetti’s interests and contributions have mostly been.


pages: 520 words: 129,887

Power Hungry: The Myths of "Green" Energy and the Real Fuels of the Future by Robert Bryce

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Bernie Madoff, carbon footprint, Cesare Marchetti: Marchetti’s constant, cleantech, collateralized debt obligation, corporate raider, correlation does not imply causation, Credit Default Swap, credit default swaps / collateralized debt obligations, decarbonisation, Deng Xiaoping, en.wikipedia.org, energy security, energy transition, flex fuel, greed is good, Hernando de Soto, hydraulic fracturing, hydrogen economy, Indoor air pollution, Intergovernmental Panel on Climate Change (IPCC), Isaac Newton, James Watt: steam engine, Menlo Park, new economy, offshore financial centre, oil shale / tar sands, oil shock, peak oil, Ponzi scheme, purchasing power parity, RAND corporation, Ronald Reagan, Silicon Valley, smart grid, Stewart Brand, Thomas L Friedman, uranium enrichment, Whole Earth Catalog

That’s the equivalent of about 30.7 billion barrels—or one cubic mile—of oil.14 The surging use of natural gas and nuclear power demonstrates and reinforces one of the most important energy megatrends of the modern era: decarbonization. Decarbonization is the ongoing global trend toward consumption of fuels that contain less carbon. This megatrend was first identified by a group of scientists that included Nebosa Nakicenovic, Arnulf Grübler, Jesse Ausubel, and Cesare Marchetti,15 who found that over the past two centuries, the process of decarbonization has been taking place in nearly every country around the world. Because consumers always want the cleanest, densest forms of energy and power that they can find, the trend will surely continue. The ratio of carbon to hydrogen atoms in the most common fuels tells the story.

In 2008, Mexico had about 54,000 megawatts of installed capacity. 9 World Nuclear Association, “World Nuclear Power Reactors and Uranium Requirements.” 10 BP Statistical Review of World Energy 2009. 11 World Nuclear Association, “World Nuclear Power Reactors and Uranium Requirements.” 12 Ibid. 13 Ibid., BP Statistical Review of World Energy 2009. 14 Hewitt Crane, Edwin Kinderman, and Ripudaman Malhotra, A Cubic Mile of Oil: Realities and Options for Averting the Looming Global Energy Crisis (New York: Oxford University Press), prepublication copy, 188. 15 See, for example, Cesare Marchetti, “On Decarbonization: Historically and Perspectively,” International Institute for Applied Systems Analysis, January 2005, http://www.iiasa.ac.at/Admin/PUB/Documents/IR-05-005.pdf. 16 Ibid. 17 International Energy Agency, “IEA Executive Director: The Climate Challenge Is Immense but We Have the Clean Technology,” November 25, 2008, http://www.iea.org/Textbase/press/pressdetail.asp?


pages: 284 words: 79,265

The Half-Life of Facts: Why Everything We Know Has an Expiration Date by Samuel Arbesman

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Albert Einstein, Alfred Russel Wallace, Amazon Mechanical Turk, Andrew Wiles, bioinformatics, British Empire, Cesare Marchetti: Marchetti’s constant, Chelsea Manning, Clayton Christensen, cognitive bias, cognitive dissonance, conceptual framework, David Brooks, demographic transition, double entry bookkeeping, double helix, Galaxy Zoo, guest worker program, Gödel, Escher, Bach, Ignaz Semmelweis: hand washing, index fund, invention of movable type, Isaac Newton, John Harrison: Longitude, Kevin Kelly, life extension, Marc Andreessen, meta analysis, meta-analysis, Milgram experiment, Nicholas Carr, p-value, Paul Erdős, Pluto: dwarf planet, publication bias, randomized controlled trial, Richard Feynman, Richard Feynman, Rodney Brooks, social graph, social web, text mining, the scientific method, Thomas Kuhn: the structure of scientific revolutions, Thomas Malthus, Tyler Cowen: Great Stagnation

Note that the distance traveled is on a logarithmic axis, meaning that the distances capable of being traveled increases exponentially over time. The thick black line shows the general exponential trend. Data from Grübler, Technology and Global Change (Cambridge University Press, 2003). These transportation speeds have clear implications for how the world around us changes. Cesare Marchetti, an Italian physicist and systems analyst, examined the city of Berlin in great detail and showed that the city has grown in tandem with technological developments. From its early dimensions, when it was hemmed in by the limits of pedestrians and coaches, to later times, when its size ballooned alongside the electric trams and subways, Berlin’s general shape was dictated by the development of ever more powerful technologies.


pages: 378 words: 110,518

Postcapitalism: A Guide to Our Future by Paul Mason

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Alfred Russel Wallace, bank run, banking crisis, banks create money, Basel III, basic income, Bernie Madoff, Bill Gates: Altair 8800, bitcoin, Branko Milanovic, Bretton Woods, BRICs, British Empire, business process, butterfly effect, call centre, capital controls, Cesare Marchetti: Marchetti’s constant, Claude Shannon: information theory, collaborative economy, collective bargaining, Corn Laws, corporate social responsibility, creative destruction, credit crunch, currency manipulation / currency intervention, currency peg, David Graeber, deglobalization, deindustrialization, deskilling, discovery of the americas, Downton Abbey, drone strike, en.wikipedia.org, energy security, eurozone crisis, factory automation, financial repression, Firefox, Fractional reserve banking, Frederick Winslow Taylor, full employment, future of work, game design, income inequality, inflation targeting, informal economy, information asymmetry, intangible asset, Intergovernmental Panel on Climate Change (IPCC), Internet of things, job automation, John Maynard Keynes: Economic Possibilities for our Grandchildren, Joseph Schumpeter, Kenneth Arrow, Kevin Kelly, knowledge economy, knowledge worker, late capitalism, low skilled workers, market clearing, means of production, Metcalfe's law, money: store of value / unit of account / medium of exchange, mortgage debt, Network effects, new economy, Norbert Wiener, Occupy movement, oil shale / tar sands, oil shock, Paul Samuelson, payday loans, Pearl River Delta, post-industrial society, precariat, price mechanism, profit motive, quantitative easing, race to the bottom, RAND corporation, rent-seeking, reserve currency, RFID, Richard Stallman, Robert Gordon, Robert Metcalfe, secular stagnation, sharing economy, Stewart Brand, structural adjustment programs, supply-chain management, The Future of Employment, the scientific method, The Wealth of Nations by Adam Smith, Transnistria, union organizing, universal basic income, urban decay, urban planning, Vilfredo Pareto, wages for housework, women in the workforce

In fact, using the IMF’s definition of recession (six months during which global growth dips below 3 per cent), they calculate that, while there were no recessions for the period 1945–73, there have been six recessions since 1973. They are confident that the Kondratieff wave is present in world GDP figures after 1870, and observable in Western economies before that. There is more evidence for the existence of long cycles in the work of Cesare Marchetti, an Italian physicist who analysed historical data on energy consumption and infrastructure projects. The result, he concluded in 1986, ‘very clearly reveals cyclic or pulsed behaviour’ in many areas of economic life, with cycles lasting roughly fifty-five years.21 Marchetti rejects the idea that these are waves, or primarily economic – preferring to call them long-term ‘pulses’ in social behaviour.


pages: 462 words: 150,129

The Rational Optimist: How Prosperity Evolves by Matt Ridley

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23andMe, agricultural Revolution, air freight, back-to-the-land, banking crisis, barriers to entry, Bernie Madoff, British Empire, call centre, carbon footprint, Cesare Marchetti: Marchetti’s constant, charter city, clean water, cloud computing, cognitive dissonance, collateralized debt obligation, colonial exploitation, colonial rule, Corn Laws, creative destruction, credit crunch, David Ricardo: comparative advantage, decarbonisation, dematerialisation, demographic dividend, demographic transition, double entry bookkeeping, Edward Glaeser, en.wikipedia.org, everywhere but in the productivity statistics, falling living standards, feminist movement, financial innovation, Flynn Effect, food miles, Gordon Gekko, greed is good, Hans Rosling, happiness index / gross national happiness, haute cuisine, Hernando de Soto, income inequality, income per capita, Indoor air pollution, informal economy, Intergovernmental Panel on Climate Change (IPCC), invention of agriculture, invisible hand, James Hargreaves, James Watt: steam engine, Jane Jacobs, John Nash: game theory, joint-stock limited liability company, Joseph Schumpeter, Kevin Kelly, knowledge worker, Kula ring, Mark Zuckerberg, meta analysis, meta-analysis, mutually assured destruction, Naomi Klein, Northern Rock, nuclear winter, oil shale / tar sands, out of africa, packet switching, patent troll, Pax Mongolica, Peter Thiel, phenotype, Plutocrats, plutocrats, Ponzi scheme, Productivity paradox, profit motive, purchasing power parity, race to the bottom, Ray Kurzweil, rent-seeking, rising living standards, Silicon Valley, spice trade, spinning jenny, stem cell, Steve Jobs, Steven Pinker, Stewart Brand, supervolcano, technological singularity, The Wealth of Nations by Adam Smith, Thorstein Veblen, trade route, transaction costs, ultimatum game, upwardly mobile, urban sprawl, Vernor Vinge, Vilfredo Pareto, wage slave, working poor, working-age population, Y2K, Yogi Berra, zero-sum game

Better kinds of nuclear power will include small, disposable, limited-life nuclear batteries for powering individual towns for limited periods and fast-breeder, pebble-bed, inherent-safe atomic reactors capable of extracting 99 per cent of uranium’s energy, instead of 1 per cent as at present, and generating even smaller quantities of short-lived waste while doing so. Modern nuclear reactors are already as different from the inherently unstable, uncontained Chernobyl ones as a jetliner is from a biplane. Perhaps one day fusion will contribute, too, but do not hold your breath. The Italian engineer Cesare Marchetti once drew a graph of human energy use over the past 150 years as it migrated from wood to coal to oil to gas. In each case, the ratio of carbon atoms to hydrogen atoms fell, from ten in wood to one in coal to a half in oil to a quarter in methane. In 1800 carbon atoms did 90 per cent of combustion, but by 1935 it was 50:50 carbon and hydrogen, and by 2100, 90 per cent of combustion may come from hydrogen – made with nuclear electricity, most probably.