Dmitri Mendeleev

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pages: 442 words: 127,300

Why We Sleep: Unlocking the Power of Sleep and Dreams by Matthew Walker

A. Roger Ekirch, active measures, caloric restriction, caloric restriction, clockwatching, Dmitri Mendeleev, Donald Trump, Exxon Valdez, impulse control, lifelogging, longitudinal study, medical residency, meta-analysis, microbiome, mouse model, orbital mechanics / astrodynamics, placebo effect, RAND corporation, Ronald Reagan, the scientific method

From this dreaming process, which I would describe as ideasthesia, have come some of the most revolutionary leaps forward in human progress. There is perhaps no better illustration highlighting the smarts of REM-sleep dreaming than the elegant solution to everything we know of, and how it fits together. I am not trying to be obtuse. Rather, I am describing the dream of Dmitri Mendeleev on February 17, 1869, which led to the periodic table of elements: the sublime ordering of all known constituent building blocks of nature. Mendeleev, a Russian chemist of renowned ingenuity, had an obsession. He felt there might be an organizational logic to the known elements in the universe, euphemistically described by some as the search for God’s abacus.

Using that wide-angle dream lens, we can apprehend the full constellation of stored information and their diverse combinatorial possibilities, all in creative servitude. MEMORY MELDING IN THE FURNACE OF DREAMS Overlay these two experimental findings onto the dream-inspired-problem-solving claims, such as those of Dmitri Mendeleev, and two clear, scientifically testable hypotheses emerge. First, if we feed a waking brain with the individual ingredients of a problem, novel connections and problem solutions should preferentially—if not exclusively—emerge after time spent in the REM dreaming state, relative to an equivalent amount of deliberative time spent awake.


pages: 189 words: 48,180

Elemental: How the Periodic Table Can Now Explain Everything by Tim James

Albert Einstein, Brownian motion, Dmitri Mendeleev, en.wikipedia.org, Ernest Rutherford, Harvard Computers: women astronomers, Isaac Newton, Murray Gell-Mann, Silicon Valley

It’s useful to have that approach because, although Newlands’s octave hypothesis was wrong, his idea of periodic repetition turned out to be on the money. Elements do obey a cyclic pattern but a much more complicated one than he had assumed. He was, for this realization, awarded the Davy Medal for Chemistry by the Royal Society in 1887. THE DREAMER Dmitri Mendeleev was born in Siberia in 1834, the youngest of probably thirteen children (historians can’t agree on the number, but I’m sure his parents knew). When his father went blind, Dmitri supported the family financially by tutoring science and, according to those who saw him in action, he was a fantastic communicator, full of passion and enthusiasm for both the subject and the art of explanation.


pages: 185 words: 55,639

The Search for Superstrings, Symmetry, and the Theory of Everything by John Gribbin

Albert Einstein, Arthur Eddington, complexity theory, dark matter, Dmitri Mendeleev, Ernest Rutherford, Fellow of the Royal Society, Isaac Newton, Murray Gell-Mann, Richard Feynman, Schrödinger's Cat, Stephen Hawking

Each element was known to consist of its own variety of atoms, and the 92 different kinds of atoms were regarded as the fundamental building blocks of nature—though it did seem rather profligate of nature to require so many ‘fundamental’ building blocks. Thanks to the pioneering work of the Siberian Dmitri Mendeleev, who lived from 1834 to 1907, in the second half of the nineteenth century chemists had begun to appreciate the relationships between atoms with different weights. Mendeleev showed that when the elements were listed in order of increasing atomic weight, starting with hydrogen, then elements with similar chemical properties recurred at regular intervals throughout the resulting periodic table.


Science...For Her! by Megan Amram

Albert Einstein, blood diamonds, butterfly effect, crowdsourcing, dark matter, Dmitri Mendeleev, double helix, Google Glasses, Isaac Newton, Kickstarter, Mark Zuckerberg, pez dispenser, Schrödinger's Cat, Steve Jobs, Ted Kaczynski, the scientific method, Wall-E, wikimedia commons

Kim is just trying too hard, as always. Poop wore it best!! Poop 81% | Kim 19% The Periodic Table of the Elements * * * The periodic table organizes chemical elements based on their atomic numbers, electron configurations, and recurring chemical properties. Before the periodic table was organized by Dmitri Mendeleev in 1869, it was just thrown together all willy-nilly! You couldn’t find hydrogen if your life depended on it, and nitrogen was stashed under the sofa in the living room. FIG. 2.9 Everything was all over the place, like how druggies hide drugs in all the little nooks and crannies of their houses.


pages: 492 words: 149,259

Big Bang by Simon Singh

Albert Einstein, Albert Michelson, All science is either physics or stamp collecting, Andrew Wiles, anthropic principle, Arthur Eddington, Astronomia nova, Brownian motion, carbon-based life, Cepheid variable, Chance favours the prepared mind, Commentariolus, Copley Medal, cosmic abundance, cosmic microwave background, cosmological constant, cosmological principle, dark matter, Dava Sobel, Defenestration of Prague, discovery of penicillin, Dmitri Mendeleev, Edmond Halley, Edward Charles Pickering, Eratosthenes, Ernest Rutherford, Erwin Freundlich, Fellow of the Royal Society, fudge factor, Hans Lippershey, Harlow Shapley and Heber Curtis, Harvard Computers: women astronomers, Henri Poincaré, horn antenna, if you see hoof prints, think horses—not zebras, Index librorum prohibitorum, invention of the telescope, Isaac Newton, Johannes Kepler, John von Neumann, Karl Jansky, Kickstarter, Louis Daguerre, Louis Pasteur, luminiferous ether, Magellanic Cloud, Murray Gell-Mann, music of the spheres, Olbers’ paradox, On the Revolutions of the Heavenly Spheres, Paul Erdős, retrograde motion, Richard Feynman, scientific mainstream, Simon Singh, Solar eclipse in 1919, Stephen Hawking, the scientific method, Thomas Kuhn: the structure of scientific revolutions, unbiased observer, Wilhelm Olbers, William of Occam

In fact, a large proportion of variable stars can be explained in this way. His work was recognised by the Royal Society, which awarded him the prestigious Copley Medal for the year’s most significant discovery in science. Three years earlier it had been won by William Herschel, and in later years it would be awarded to Dmitri Mendeleev for developing the periodic table, to Einstein for his work on relativity, and to Francis Crick and James Watson for unravelling the secret of DNA. Figure 40 The variation in the brightness of the star Algol is symmetric and periodic, with a minimum brightness every 68 hours and 50 minutes.

In many ways, the great sacrifices made by the Curies in their cramped Parisian laboratory served only to highlight the huge lack of understanding as to what was going on inside the atom. Scientists seemed to have gone backwards in their knowledge – just a few decades earlier they had claimed to fully comprehend the building blocks of matter thanks to the periodic table. In 1869, the Russian chemist Dmitri Mendeleev had drawn up a chart that listed all the elements then known, from hydrogen to uranium. By combining the atoms of different elements in the periodic table in various ratios, it was possible to build molecules and explain every material under the Sun, inside the Sun and beyond the Sun. For example, two atoms of hydrogen plus one atom of oxygen made one molecule of water, H2O.


pages: 277 words: 72,603

Built: The Hidden Stories Behind Our Structures by Roma Agrawal

3D printing, British Empire, clean water, David Attenborough, Dmitri Mendeleev, Guggenheim Bilbao, Isaac Newton, John Snow's cholera map, Tacoma Narrows Bridge, the scientific method

Water in large proportions made a material resistant to it, and brittle materials were ruled by fire. Ever curious and inventive, the Romans manipulated these materials to better their properties, which is how they made their renowned concrete. They may not have had the periodic table (it would be a while before Dmitri Mendeleev published the original version of the table in 1869), but they knew that the properties of a material depended on the proportions of its elements, and they could be changed by exposing it to other elements. For a long time, however, humans simply built from the materials that Nature provided, without changing their fundamental properties.


pages: 209 words: 68,587

Stephen Hawking by Leonard Mlodinow

Albert Michelson, cosmic microwave background, cosmological constant, cosmological principle, dark matter, Dmitri Mendeleev, Ernest Rutherford, Isaac Newton, Murray Gell-Mann, Nelson Mandela, Richard Feynman, Richard Feynman: Challenger O-ring, Stephen Hawking, the scientific method

A decade after Stephen’s Fairchild year, I arrived at Caltech and had the office next to Murray, and down the hall from Feynman. Gell-Mann was “Murray” to me and to most people. He derived his greatest fame from discovering a mathematical scheme to classify and understand the properties of elementary particles. The achievement earned him comparisons with Dmitri Mendeleev, who accomplished an analogous feat when he invented the periodic table of elements. Feynman was “Dick” to a far smaller group. His most important contribution was to formulate a new way of conceptualizing quantum theory and of doing the calculations one needed to carry out in order to apply it—called Feynman diagrams.


Wonders of the Universe by Brian Cox, Andrew Cohen

a long time ago in a galaxy far, far away, Albert Einstein, Albert Michelson, Arthur Eddington, California gold rush, Cepheid variable, cosmic microwave background, dark matter, Dmitri Mendeleev, Isaac Newton, James Watt: steam engine, Johannes Kepler, Karl Jansky, Magellanic Cloud, Mars Rover, Solar eclipse in 1919, Stephen Hawking, the scientific method, trade route

At its simplest, this chart is a list of the chemical elements, fundamental units of matter, which were considered to be the smallest building blocks of the world. However, this table is much more than just a list. Although elemental theories of matter were first postulated in Greece, it wasn’t until 6 March 1869 that the Russian chemist Dmitri Mendeleev finally tamed the ever-expanding list of the basic constituents of matter. Mendeleev’s genius was to arrange the list of the sixty-six then-known elements into a table according to their chemical properties. In the process, the table not only provided a neat way of grouping the elements according to their properties, but also predicted the existence of eight elements yet to be discovered.


pages: 356 words: 95,647

Sun in a Bottle: The Strange History of Fusion and the Science of Wishful Thinking by Charles Seife

Albert Einstein, anti-communist, Brownian motion, correlation does not imply causation, Dmitri Mendeleev, Ernest Rutherford, Fellow of the Royal Society, Gary Taubes, Isaac Newton, John von Neumann, Mikhail Gorbachev, Norman Macrae, Project Plowshare, Richard Feynman, Ronald Reagan, the scientific method, Yom Kippur War

More than two thousand years later, a steady march of experimentation and observation led scientists to the conclusion that Democritus was essentially correct: matter is made up of tiny atoms. Chemists had led the way; the work of chemists such as the Briton John Dalton, the Italian Amedeo Avogadro, and the Russian Dmitri Mendeleev began to produce a picture in which all matter consisted of a collection of invisible “elemental” particles. Water, for example, was made up of two particles of hydrogen and one of oxygen; alcohol had two of carbon, six of hydrogen, and one of oxygen. There was only a handful of known elements, and they each had different properties.


pages: 315 words: 89,861

The Simulation Hypothesis by Rizwan Virk

3D printing, Albert Einstein, Apple II, artificial general intelligence, augmented reality, Benoit Mandelbrot, bioinformatics, butterfly effect, Colossal Cave Adventure, discovery of DNA, Dmitri Mendeleev, Elon Musk, en.wikipedia.org, Ernest Rutherford, game design, Google Glasses, Isaac Newton, John von Neumann, Kickstarter, mandelbrot fractal, Marc Andreessen, Minecraft, natural language processing, Pierre-Simon Laplace, Ralph Waldo Emerson, Ray Kurzweil, Richard Feynman, Schrödinger's Cat, Search for Extraterrestrial Intelligence, Silicon Valley, Stephen Hawking, Steve Jobs, Steve Wozniak, technological singularity, Turing test, Vernor Vinge, Zeno's paradox

This gave him the idea of having the thread at the tip of the needle, which was the final piece he needed to get his sewing machine to work. Chemist August Kekulé supposedly came up with the structure of the benzene molecule (which is a circular structure) after he had a dream in which a snake was eating its tail. And Dmitri Mendeleev, also a chemist, saw the elements all organize into the columns and rows we know as the Periodic Table while he was dozing in front of a fireplace at a resort on the Caspian Sea. Mystics and shamans of all traditions, on the other hand, believe that dreams are a way for us to tap into other worlds.


pages: 313 words: 91,098

The Knowledge Illusion by Steven Sloman

Affordable Care Act / Obamacare, Air France Flight 447, attribution theory, bitcoin, Black Swan, Cass Sunstein, combinatorial explosion, computer age, crowdsourcing, Dmitri Mendeleev, Elon Musk, Ethereum, Flynn Effect, Hernando de Soto, hindsight bias, hive mind, indoor plumbing, Isaac Newton, John von Neumann, libertarian paternalism, Mahatma Gandhi, Mark Zuckerberg, meta-analysis, obamacare, prediction markets, randomized controlled trial, Ray Kurzweil, Richard Feynman, Richard Thaler, Rodney Brooks, Rosa Parks, single-payer health, speech recognition, stem cell, Stephen Hawking, Steve Jobs, technological singularity, The Coming Technological Singularity, The Wisdom of Crowds, Vernor Vinge, web application, Whole Earth Review, Y Combinator

Some of us have a love/hate relationship with it after having had to memorize it for chemistry class. The periodic table is the heart of modern chemistry. It is a table that lists all the elements—the building blocks of nature—in a way that reveals how they are related to one another and what their properties are. Most of us are taught that Dmitri Mendeleev formulated the periodic table, but there is wide agreement that Mendeleev did not do all the necessary work alone. He built upon the work of others, like the French chemist Antoine Lavoisier. But Mendeleev is given the lion’s share of the credit. He was considered so important by other scientists that a new element was named after him, mendelevium.


pages: 398 words: 100,679

The Knowledge: How to Rebuild Our World From Scratch by Lewis Dartnell

agricultural Revolution, Albert Einstein, Any sufficiently advanced technology is indistinguishable from magic, clean water, Dava Sobel, decarbonisation, discovery of penicillin, Dmitri Mendeleev, global village, Haber-Bosch Process, invention of movable type, invention of radio, invention of writing, iterative process, James Watt: steam engine, John Harrison: Longitude, Kim Stanley Robinson, lone genius, low earth orbit, mass immigration, nuclear winter, off grid, Richard Feynman, technology bubble, the scientific method, Thomas Kuhn: the structure of scientific revolutions, trade route

The modern periodic table is a colossal monument to human achievement, as impressive as the Egyptian pyramids or any of the other wonders of the world. Far more than just a comprehensive list of different elements that chemists have identified over the years, it is a way of organizing knowledge that allows you to predict details about what you have not yet found. For example, when the Russian chemist Dmitri Mendeleev first assembled a periodic table in 1869 of the 60-odd elements then known, he found gaps in the brickwork—placeholders corresponding to missing substances. But the brilliant thing about the arrangement, where the elements are placed according to their properties, is that it enabled him to predict precisely what these hypothetical elements would be like—such as eka-aluminum, the missing piece in the table immediately below aluminum.


Calling Bullshit: The Art of Scepticism in a Data-Driven World by Jevin D. West, Carl T. Bergstrom

airport security, algorithmic bias, Amazon Mechanical Turk, Andrew Wiles, bitcoin, cloud computing, computer vision, correlation coefficient, correlation does not imply causation, crowdsourcing, cryptocurrency, delayed gratification, disinformation, Dmitri Mendeleev, Donald Trump, Elon Musk, epigenetics, Estimating the Reproducibility of Psychological Science, experimental economics, invention of the printing press, John Markoff, longitudinal study, Lyft, meta-analysis, new economy, p-value, Pluto: dwarf planet, publication bias, RAND corporation, randomized controlled trial, replication crisis, ride hailing / ride sharing, Ronald Reagan, selection bias, self-driving car, Silicon Valley, Silicon Valley startup, social graph, Socratic dialogue, Stanford marshmallow experiment, statistical model, stem cell, superintelligent machines, the scientific method, theory of mind, Tim Cook: Apple, twin studies, Uber and Lyft, Uber for X, uber lyft, When a measure becomes a target

Glass slippers take one type of data and shoehorn it into a visual form designed to display another. In doing so, they trade on the authority of good visualizations to appear authoritative themselves. They are to data visualization what mathiness is to mathematical equations. The chemist Dmitri Mendeleev developed the periodic table in the second half of the nineteenth century. His efforts were a triumph of data visualization as a tool for organizing patterns and generating predictions in science. The periodic table is an arrangement of the chemical elements from lightest to heaviest. The left-to-right positions reflect what we now understand to be the fundamental atomic structure of each element, and predict the chemical interactions of those elements.


pages: 480 words: 112,463

The Golden Thread: How Fabric Changed History by Kassia St Clair

barriers to entry, bitcoin, blockchain, butterfly effect, Dmitri Mendeleev, Elon Musk, Francisco Pizarro, gender pay gap, ghettoisation, gravity well, Jacquard loom, James Hargreaves, Joseph-Marie Jacquard, Kickstarter, out of africa, Rana Plaza, Silicon Valley, Silicon Valley startup, Skype, spinning jenny, trade route, transatlantic slave trade, Works Progress Administration

Even more tantalisingly, from a commercial point of view, short lengths of viscose fibre, known as ‘staples’, can be mixed with other fibres, such as cotton or wool, before being woven. This has led to the creation of new fabrics to market to consumers, who have also benefitted from lower prices.7 For western scientists and businessmen, the prospect of finally being able to shake the East’s dominance over luxury fabric production was wildly exciting. Dmitri Mendeleev, the Russian chemist who set out the periodic table, warned that because the production of rayon was still ‘in its first, or embryonic stage of development . . . it is best to talk about it with caution’. Notwithstanding such reticence, he continued that ‘the victory of viscose will be a new triumph of science . . .


pages: 624 words: 104,923

QI: The Book of General Ignorance - The Noticeably Stouter Edition by Lloyd, John, Mitchinson, John

Admiral Zheng, Albert Einstein, Barry Marshall: ulcers, British Empire, discovery of penicillin, disinformation, Dmitri Mendeleev, Fellow of the Royal Society, Ignaz Semmelweis: hand washing, invention of the telephone, James Watt: steam engine, Kickstarter, Kuiper Belt, lateral thinking, Magellanic Cloud, Mars Rover, Menlo Park, Olbers’ paradox, On the Revolutions of the Heavenly Spheres, placebo effect, Pluto: dwarf planet, trade route, two and twenty, V2 rocket, Vesna Vulović

As these liquids are very dense (being metals), bricks, horseshoes and cannon balls theoretically float in them. Gallium (Ga) was discovered by French chemist Lecoq de Boisbaudran in 1875. Everyone assumed it was a patriotic name but gallus is Latin for ‘a Gaul’ and ‘rooster’ – as in ‘Lecoq’. It was the first new element to confirm Dmitri Mendeleev’s prediction of the periodic table. Gallium is used chiefly in microchips because of its strange electronic properties. Compact disc players also make use of it because when mixed with arsenic it transforms an electric current directly into laser light, which is used to ‘read’ the data from the discs.


pages: 467 words: 114,570

Pathfinders: The Golden Age of Arabic Science by Jim Al-Khalili

agricultural Revolution, Albert Einstein, Andrew Wiles, Book of Ingenious Devices, colonial rule, Commentariolus, Dmitri Mendeleev, Eratosthenes, Henri Poincaré, invention of the printing press, invention of the telescope, invention of the wheel, Isaac Newton, Islamic Golden Age, Johannes Kepler, Joseph Schumpeter, Kickstarter, liberation theology, retrograde motion, scientific worldview, Silicon Valley, Simon Singh, stem cell, Stephen Hawking, the scientific method, Thomas Malthus, trade route, William of Occam

The techniques that were developed drove a thriving and successful industry, but we also see in the work of Jābir the beginning of chemistry as an empirical science motivated by a desire to understand how the world is made up. The periodic table one finds on the wall of every school science laboratory was conceived by the Russian chemist Dmitri Mendeleev in 1869. Its key idea is to group together substances with similar properties, as well as arranging them according to their atomic weight. On one side, for instance, are the inert gases and, on the other, the volatile metals. It is a triumph of classification, giving scientists a way of organizing their knowledge of the material world, something mankind has been striving to do since the dawn of time.


pages: 434 words: 135,226

The Music of the Primes by Marcus Du Sautoy

Ada Lovelace, Andrew Wiles, Arthur Eddington, Augustin-Louis Cauchy, computer age, Dava Sobel, Dmitri Mendeleev, Eratosthenes, Erdős number, Georg Cantor, German hyperinflation, global village, Henri Poincaré, Isaac Newton, Jacquard loom, lateral thinking, music of the spheres, New Journalism, P = NP, Paul Erdős, Richard Feynman, Rubik’s Cube, Search for Extraterrestrial Intelligence, Simon Singh, Solar eclipse in 1919, Stephen Hawking, Turing machine, William of Occam, Wolfskehl Prize, Y2K

Whilst the Greeks mistakenly believed fire, air, water and earth to be the building blocks of matter, they were spot on when it came to identifying the atoms of arithmetic. For many centuries, chemists strove to identify the basic constituents of their subject, and the Greeks’ intuition finally culminated in Dmitri Mendeleev’s Periodic Table, a complete description of the elements of chemistry. In contrast to the Greeks’ head start in identifying the building blocks of arithmetic, mathematicians are still floundering in their attempts to understand their own table of prime numbers. The librarian of the great ancient Greek research institute in Alexandria was the first person we know of to have produced tables of primes.


pages: 653 words: 155,847

Energy: A Human History by Richard Rhodes

Albert Einstein, animal electricity, California gold rush, Cesare Marchetti: Marchetti’s constant, Copley Medal, dark matter, David Ricardo: comparative advantage, decarbonisation, demographic transition, Dmitri Mendeleev, Drosophila, Edmond Halley, energy transition, Ernest Rutherford, Fellow of the Royal Society, flex fuel, Garrett Hardin, Ida Tarbell, income inequality, Intergovernmental Panel on Climate Change (IPCC), invention of the steam engine, invisible hand, Isaac Newton, James Watt: steam engine, joint-stock company, Menlo Park, Mikhail Gorbachev, new economy, nuclear winter, oil rush, oil shale / tar sands, oil shock, peak oil, Ralph Nader, Richard Feynman, Ronald Reagan, selection bias, Simon Kuznets, The Rise and Fall of American Growth, Thomas Malthus, Thorstein Veblen, Tragedy of the Commons, uranium enrichment, urban renewal, Vanguard fund, working poor, young professional

For example, he said, “the more carbon atoms we get into the compounds, the heavier the fuel becomes.”43 That practical perspective now informed the Midgley group’s pursuit of an antiknock compound. One of their consultants, an MIT chemist named Robert E. Wilson, showed Midgley a periodic table he had constructed on a different principle of organization from Dmitri Mendeleev’s original principle of chemical similarities. Wilson’s table highlighted regularities important to organic chemists.II “Tom was greatly interested in this,” Wilson recalled, “especially since he believed that the antiknock properties of various agents were primarily properties of the elements, and he had some indications that the antiknock effect of an element varied predictably with its location in the periodic system.”44 Midgley’s trail of increasingly heavy stinkers suppressing knock with increasing effectiveness was the crucial clue.


The Greatest Show on Earth: The Evidence for Evolution by Richard Dawkins

Alfred Russel Wallace, Andrew Wiles, Arthur Eddington, back-to-the-land, Claude Shannon: information theory, correlation does not imply causation, Craig Reynolds: boids flock, Danny Hillis, David Attenborough, discovery of DNA, Dmitri Mendeleev, domesticated silver fox, double helix, en.wikipedia.org, epigenetics, experimental subject, if you see hoof prints, think horses—not zebras, invisible hand, Louis Pasteur, out of africa, phenotype, Thomas Malthus

Fred Hoyle has ingeniously speculated that, if we had been born with eight digits and therefore become accustomed to octal arithmetic instead of decimal, we might have invented binary arithmetic and hence electronic computers a century earlier than we did (since 8 is a power of 2). * Alas, the popular legend that it came to Dmitri Mendeleev in a dream may be false. CHAPTER 5 BEFORE OUR VERY EYES I HAVE used the metaphor of a detective, coming on the scene of a crime after it is all over and reconstructing from the surviving clues what must have happened. But perhaps I was too ready to concede the impossibility of viewing evolution as an eye witness.


What We Cannot Know: Explorations at the Edge of Knowledge by Marcus Du Sautoy

Albert Michelson, Andrew Wiles, Antoine Gombaud: Chevalier de Méré, Arthur Eddington, banking crisis, bet made by Stephen Hawking and Kip Thorne, Black Swan, Brownian motion, clockwork universe, cosmic microwave background, cosmological constant, dark matter, Dmitri Mendeleev, Edmond Halley, Edward Lorenz: Chaos theory, Ernest Rutherford, Georg Cantor, Hans Lippershey, Harvard Computers: women astronomers, Henri Poincaré, invention of the telescope, Isaac Newton, Johannes Kepler, Magellanic Cloud, mandelbrot fractal, MITM: man-in-the-middle, Murray Gell-Mann, music of the spheres, Necker cube, Paul Erdős, Pierre-Simon Laplace, Richard Feynman, Skype, Slavoj Žižek, Solar eclipse in 1919, stem cell, Stephen Hawking, technological singularity, Thales of Miletus, Turing test, wikimedia commons

It seemed that all compounds came in proportions that were whole-number ratios. For example, aluminium sulphide was given algebraically as 2Al + 3S = Al2S3, elements combining in a 2-to-3 ratio. Elements never combined in a non-whole-number relationship. It was like musical harmony at the heart of the chemical world. The music of tiny spheres. The Russian scientist Dmitri Mendeleev is remembered for laying out this growing list of molecular ingredients in such a way that a pattern began to emerge, a pattern based on whole numbers and counting. It seemed that the Pythagorean belief in the power of number was making a comeback. Like several scientists before him, Mendeleev arranged them in increasing relative weight, but he realized that to get the patterns he could see emerging he needed to be flexible.