Scientific wager

A scientific wager is a wager whose outcome is settled by scientific method. They typically consist of an offer to pay a certain sum of money on the scientific proof or disproof of some currently uncertain statement. Some wagers have specific date restrictions for collection, but many are open. Wagers occasionally exert a powerful galvanizing effect on society and the scientific community.

Notable scientists who have made scientific wagers include Stephen Hawking and Richard Feynman. Stanford Linear Accelerator has an open book containing about 35 bets in particle physics dating back to 1980; many are still unresolved.

Notable scientific wagers

• In 1684, Christopher Wren announced that he would give a book worth 40 shillings (equivalent to about £280 in present-day terms) to anyone who could deduce Kepler's laws from the inverse-square law. Isaac Newton's musings on this problem eventually grew into his Principia. However, Newton was too late to qualify for the book. Historian Alan Shapiro (University of Minnesota) has stated that this episode was "undoubtedly one of the most crucial wagers in scientific history".
• In 1870, Alfred Russel Wallace bet a flat-Earth theorist named John Hampden that he could prove the flat Earth hypothesis incorrect. The sum staked was £500 (equivalent to about £43000 in present day terms). A test (now known as the Bedford Level experiment) involving a stretch of the Old Bedford River, in Norfolk, was agreed on: Wallace measured the curvature of the canal's surface using two markers separated by about 5 kilometres (3.1 mi) and suspended at equal heights above the water's surface. Using a telescope mounted 5 km from one of the markers, Wallace established that the nearer one appeared to be the higher of the two. An independent referee agreed that this showed the Earth's surface to curve away from the telescope, and so Wallace won his money. However, Hampden never accepted the result and made increasingly unpleasant threats to Wallace.
• In 1959, Richard Feynman bet $1,000 (equivalent to about $8000 in present day terms) that no one could construct a motor no bigger than 1/64 of an inch (0.4 mm) on a side. He lost the bet when Bill McLellan, using amateur radio skills, constructed such a motor. Feynman had never formalized the bet because he couldn't define his terms sufficiently and precisely, but paid up anyway; Feynman is also on record as saying that he was disappointed with the outcome because he had hoped his reward would stimulate some new fabrication technology, but McLellan's motor used only existing techniques. Physicist Philip Ball, writing in Nature Materials, discussed this episode and asked, "Do we, like Feynman, always underestimate what our current technologies can achieve?"
• In 1964, James Randi initiated his $1,000 challenge, which has grown to $1,000,000. Today the James Randi Educational Foundation offers the One Million Dollar Paranormal Challenge which will pay one million US dollars to "any person who demonstrates any psychic, supernatural, or paranormal ability under satisfactory observation". To date no-one has succeeded in this challenge.
• In 1975, cosmologist Stephen Hawking bet fellow cosmologist Kip Thorne a subscription to Penthouse magazine for Thorne against four years of Private Eye for him that Cygnus X-1 would turn out to not be a black hole. In 1990, Hawking acknowledged that he had lost the bet. Hawking's explanation for his position was that if black holes didn't actually exist much of his research would be incorrect, but at least he'd have the consolation of winning the bet.
• In 1978, chess International Master David Levy won £1250 from four artificial intelligence experts by never losing to a chess program in a ten-year span from 1968 to 1978.
• In 1980, biologist Paul R. Ehrlich bet economist Julian Lincoln Simon that the price of a portfolio of $200 of each of five mineral commodities (copper, chromium, nickel, tin, and tungsten) would rise over the next 10 years. He lost, and paid the amount the total price had declined: $576.07. See: Simon–Ehrlich wager
• In 1997, Stephen Hawking and Kip Thorne made a bet with John Preskill on the ultimate resolution of the apparent contradiction between Hawking radiation resulting in loss of information, and a requirement of quantum mechanics that information cannot be destroyed. Hawking and Thorne bet that information must be lost in a black hole; Preskill bet that it must not. The formal wager was: "When an initial pure quantum state undergoes gravitational collapse to form a black hole, the final state at the end of black hole evaporation will always be a pure quantum state". The stake was an encyclopaedia of the winner's choice, from which "information can be recovered at will". Hawking conceded the bet in 2004, giving a baseball encyclopaedia to John Preskill. Thorne has not formally conceded. See: Thorne-Hawking-Preskill bet
• In 2005, British climate scientist James Annan proposed bets with global warming denialists concerning whether future temperatures will increase. Two Russian solar physicists, Galina Mashnich and Vladimir Bashkirtsev, accepted the wager of US$10,000 that the average global temperature during 2012–2017 would be lower than during 1998–2003. Previously, Annan first directly challenged Richard Lindzen. Lindzen had been willing to bet that global temperatures would drop over the next 20 years. Annan says that Lindzen wanted odds of 50–1 against falling temperatures. Lindzen, however, says that he asked for 2–1 odds against a temperature rise of over 0.4 °C. Annan and other proponents of global warming state they have challenged other denialists to bets over global warming that were not accepted, including Annan's attempt in 2005 to accept a bet that had been offered by Patrick Michaels in 1998 that temperatures would be cooler after ten years. Annan made a bet in 2011 with Doctor David Whitehouse that the Met Office temperature would set a new annual record by the end of the year. Annan was declared to have lost on January 13, 2012.
• In 2005, The Guardian columnist George Monbiot challenged Myron Ebell of the Competitive Enterprise Institute to a GB£5,000 bet of global warming versus global cooling.
• In 2012, Stephen Hawking lost $100 to Gordon Kane of the University of Michigan because of the Higgs boson discovery.
• Zvi Bern has won many bets connected to quantum gravity.

See also

• Long Now Foundation#Long Bet Project
• The efforts of photographer Eadweard Muybridge to capture the motion of a galloping horse were not part of a wager, contrary to popular opinion.
• Pascal's wager is not a wager in the sense used in this article, nor is it scientific.