CROWN, JULY 2015The Massachusetts Institute of Technology, better known as MIT, is one of the world’s scientific powerhouses. Founded in 1861 in Cambridge, Massachusetts, it boasts nine current Nobel laureates among its one thousand professors (as of 2014). Its alumni include astronauts (one-third of NASA’s space flights were manned by MIT graduates), politicians (including Kofi Annan, former Secretary-General of the United Nations and winner of the 2001 Nobel Peace Prize), entrepreneurs such as William Reddington Hewlett, co-founder of Hewlett-Packard—and, of course, lots of scientists, including the Nobel Prize-winning architect of quantum electrodynamics, Richard Feynman. Yet one of its most illustrious inhabitants is not human; it is in fact a plant, an apple tree. Growing in the President’s Garden in the shadow of the institute’s iconic Pantheonesque dome is a cutting from another tree kept at England’s Royal Botanic Gardens, which is a direct descendant of the actual tree under which Sir Isaac Newton supposedly sat when he observed the falling of his famous apple.
The simple yet profound question that Newton had been contemplating sitting under a tree at his mother’s Lincolnshire farm three and a half centuries ago was: why do apples fall? It may seem churlish to suggest that his answer, one that revolutionized physics and indeed all of science, could be inadequate in any way; but there is an aspect of that famous scene that went unnoticed by Newton and has gone unremarked upon ever since: what was the apple doing up in the tree in the first place? If the apple’s accelerated descent to the ground was puzzling, then how much more inexplicable was the bolting together of Lincolnshire air and water to form a spherical object perched in the branches of a tree? Why did Newton wonder about the comparatively trivial matter of the pull of the earth’s gravity on the apple and overlook entirely the utterly incomprehensible puzzle of the fruit’s formation in the first place?
One factor that might explain Isaac Newton’s lack of curiosity about this was the predominant seventeenth-century view that although the brute mechanics of all objects, including living ones, might be accounted for by physical laws, their peculiar inner dynamic (dictating, among other things, how apples grow) was driven by that vital force or élan vital which flowed from a supernatural source beyond the reach of any godless mathematical equation. But, as we have already discovered, vitalism was blown away by subsequent advances in biology, genetics, biochemistry and molecular biology. No serious scientist today doubts that life can be accounted for within the sphere of science; but there remains a question mark over which of the sciences can best provide that account. Despite the alternative claims of scientists such as Schrödinger, most biologists still believe that the classical laws are sufficient, with Newtonian forces acting upon ball and stick biomolecules that behave like, well, balls and sticks. Even Richard Feynman, one of Schrödinger’s intellectual successors, described photosynthesis in strictly classical terms with “sunlight that comes down and knocks this oxygen away from the carbon,” as if light were some kind of golf club able to whack the oxygen golf ball out of the carbon dioxide molecule.
Molecular biology and quantum mechanics developed in parallel, rather than cooperatively. Biologists hardly attended physics lectures and physicists paid little attention to biology. But in April 2007, a group of MIT-based physicists and mathematicians who worked in a rather esoteric area called quantum information theory were enjoying one of their regular journal clubs (with each member taking a turn at presenting a new paper they had found in the scientific literature) when one of the group arrived with a copy of the New York Times carrying an article which suggested plants were quantum computers (more on these remarkable machines in chapter 8). The group exploded into laughter. One of the team, Seth Lloyd, recalled first hearing about this “quantum hanky-panky.” “We thought that was really hysterical . . . It’s like, ‘Oh my God, that’s the most crackpot thing I’ve heard in my life!’” The cause of their incredulity was the fact that many of the brightest and best-funded research groups in the world had spent decades trying to figure out how to build a quantum computer, a machine that could carry out certain calculations much faster and far more efficiently than the most powerful computers available in the world today. It relies on digital bits of information that are normally either 0 or 1, to be both 0 and 1 simultaneously and therefore able to pursue all possible calculations at once—the ultimate in parallel processing. The New York Times article was claiming a humble blade of grass was able to perform the kind of quantum trickery that lay at the heart of quantum computing. No wonder these MIT researchers were incredulous. They might not be able to build a working quantum computer but, if the article was right, they could eat one in their lunchtime salad!
Excerpted from Life on the Edge: The Coming Age of Quantum Biology by Johnjoe McFadden and Jim Al-Khalili. Published in 2015 by Crown Publishers, an imprint of the Crown Publishing Group, a division of Random House LLC. © Johnjoe McFadden and Jim Al-Khalili, 2015.