Author Archives: Attention to the Unseen

Is our universe fine-tuned for the existence of life?

Tim Maudlin writes: Ever since the 1920s when Edwin Hubble discovered that all visible galaxies are receding from one another, cosmologists have embraced a general theory of the history of the visible universe. In this view, the visible universe originated from an unimaginably compact and hot state. Prior to 1980, the standard Big Bang models had the universe expanding in size and cooling at a steady pace from the beginning of time until now. These models were adjusted to fit observed data by selecting initial conditions, but some began to worry about how precise and special those initial conditions had to be.

For example, Big Bang models attribute an energy density — the amount of energy per cubic centimetre — to the initial state of the cosmos, as well as an initial rate of expansion of space itself. The subsequent evolution of the universe depends sensitively on the relation between this energy density and the rate of expansion. Pack the energy too densely and the universe will eventually recontract into a big crunch; spread it out too thin and the universe will expand forever, with the matter diluting so rapidly that stars and galaxies cannot form. Between these two extremes lies a highly specialised history in which the universe never recontracts and the rate of expansion eventually slows to zero. In the argot of cosmology, this special situation is called W = 1. Cosmological observation reveals that the value of W for the visible universe at present is quite near to 1. This is, by itself, a surprising finding, but what’s more, the original Big Bang models tell us that W = 1 is an unstable equilibrium point, like a marble perfectly balanced on an overturned bowl. If the marble happens to be exactly at the top it will stay there, but if it is displaced even slightly from the very top it will rapidly roll faster and faster away from that special state.

This is an example of cosmological fine-tuning. In order for the standard Big Bang model to yield a universe even vaguely like ours now, this particular initial condition had to be just right at the beginning. Some cosmologists balked at this idea. It might have been just luck that the Solar system formed and life evolved on Earth, but it seemed unacceptable for it to be just luck that the whole observable universe should have started so near the critical energy density required for there to be cosmic structure at all. [Continue reading…]

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8,000 years ago, the overwhelming majority of men never reproduced

Francie Diep writes: Once upon a time, 4,000 to 8,000 years after humanity invented agriculture, something very strange happened to human reproduction. Across the globe, for every 17 women who were reproducing, passing on genes that are still around today—only one man did the same.

“It wasn’t like there was a mass death of males. They were there, so what were they doing?” asks Melissa Wilson Sayres, a computational biologist at Arizona State University, and a member of a group of scientists who uncovered this moment in prehistory by analyzing modern genes.

Another member of the research team, a biological anthropologist, hypothesizes that somehow, only a few men accumulated lots of wealth and power, leaving nothing for others. These men could then pass their wealth on to their sons, perpetuating this pattern of elitist reproductive success. Then, as more thousands of years passed, the numbers of men reproducing, compared to women, rose again. “Maybe more and more people started being successful,” Wilson Sayres says. In more recent history, as a global average, about four or five women reproduced for every one man. [Continue reading…]

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How trees calm us down

Alex Hutchinson writes: In 1984, a researcher named Roger Ulrich noticed a curious pattern among patients who were recovering from gallbladder surgery at a suburban hospital in Pennsylvania. Those who had been given rooms overlooking a small stand of deciduous trees were being discharged almost a day sooner, on average, than those in otherwise identical rooms whose windows faced a wall. The results seemed at once obvious — of course a leafy tableau is more therapeutic than a drab brick wall — and puzzling. Whatever curative property the trees possessed, how were they casting it through a pane of glass?

That is the riddle that underlies a new study in the journal Scientific Reports by a team of researchers in the United States, Canada, and Australia, led by the University of Chicago psychology professor Marc Berman. The study compares two large data sets from the city of Toronto, both gathered on a block-by-block level; the first measures the distribution of green space, as determined from satellite imagery and a comprehensive list of all five hundred and thirty thousand trees planted on public land, and the second measures health, as assessed by a detailed survey of ninety-four thousand respondents. After controlling for income, education, and age, Berman and his colleagues showed that an additional ten trees on a given block corresponded to a one-per-cent increase in how healthy nearby residents felt. “To get an equivalent increase with money, you’d have to give each household in that neighborhood ten thousand dollars — or make people seven years younger,” Berman told me.

Are such numbers fanciful? The emerald ash borer, which has killed a hundred million trees across North America in recent years, offers a grim natural experiment. A county-by-county analysis of health records by the U.S. Forest Service, between 1990 and 2007, found that deaths related to cardiovascular and respiratory illnesses rose in places where trees succumbed to the pest, contributing to more than twenty thousand additional deaths during the study period. The Toronto data shows a similar link between tree cover and cardio-metabolic conditions such as heart disease, stroke, and diabetes. For the people suffering from these conditions, an extra eleven trees per block corresponds to an income boost of twenty thousand dollars, or being almost one and a half years younger. [Continue reading…]

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The arrow of time

Andrew Grant writes: In T.H. White’s fantasy novel The Once and Future King, Merlyn the magician suffers from a rare and incurable condition: He experiences time in reverse. He knows what will happen, he laments, but not what has happened. “I have to live backwards from in front, while surrounded by a lot of people living forwards from behind,” he explains to a justifiably confused companion.

While Merlyn is fictional, the backward flow of time should not be. As the society of ants in White’s novel proclaimed, “everything not forbidden is compulsory,” and the laws of physics do not forbid time to run backward. Equations that determine the acceleration of a rocket or the momentum of a billiard ball all work just as well with time flowing backward as forward. Yet unlike Merlyn, we remember the past but not the future. We get older but never younger. There is a distinct arrow of time pointing in one direction.

For nearly 140 years, scientists have tried to rule out the backward flow of time by way of nature’s preference for disorder. Left alone, nature transforms the neat into the messy, a one-way progression that many physicists have used to define time’s direction. But if nature prefers disorder now, it always has. The challenge is figuring out why the universe started out so orderly — thereby allowing disorder to grow and time to march forward — when the early universe should have been messy. Despite many proposals, physicists have not been able to agree on a satisfying explanation. [Continue reading…]

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How whales are struggling to make themselves heard in the world’s increasingly noisy oceans

Peter Brannen writes: At 5:30am I awoke to the sound of the diesel chug-chugging of a lone lobster boat carving into the glassy Atlantic. An audience of shrieking gulls hushed in the engine’s wake as it rumbled through the narrow strait that separates the United States from Canada. After the boat pushed out into the open ocean, the gulls resumed their gossip, and I began preparing for a day on the water, still groggy from the night before, after joining a group of researchers over beer. I had come to Lubec in Maine with a bizarre question: what was 9/11 like for whales?

I sleepwalked to the pier and helped pack a former Coast Guard patrol boat with boxes of underwater audio-visual equipment, as well as a crossbow built for daring, drive-by whale biopsies. A pod of 40 North Atlantic right whales had been spotted south of Nova Scotia the day before and, with only a few hundred of the animals left in existence, any such gathering meant a potential field research coup. ‘They even got a poop sample!’ one scientist excitedly told me. The boat roared to life and we slipped past postcard-ready lighthouses and crumbling, cedar-shingled herring smokehouses. Lisa Conger, a biologist at the US National Oceanic and Atmospheric Administration (NOAA), manned the wheel of our boat, dodging Canadian islands and fishing weirs. As the Bay of Fundy opened before us, a container ship lumbered by to our stern: a boxy, smoking juggernaut, as unstoppable as the tide.

‘After 9/11, we were the only ones out here,’ Conger said over the wind and waves. While this tucked-away corner of the Atlantic might seem far from the rattle of world affairs, the terrorist attacks on New York City and Washington DC of 11 September 2001 changed the marine world of the Bay of Fundy, too.

Conger leads the field team in Lubec for Susan Parks, a biology professor at Syracuse University. As a graduate student, Parks found that right whales were trying to adapt to a gradual crescendo of man-made noise in the oceans. In one study, she compared calls recorded off Martha’s Vineyard in 1956, and off Argentina in the 1977, with those in the North Atlantic in 2000. Christopher Clark, her advisor, had recorded the Argentine whales and, when Parks first played back their calls, she thought there must be some sort of mistake.

‘It was older equipment – reel-to-reel tapes which I’d never used before – so I went to Chris to ask if I had the speed of the tape wrong because the whales sounded so much lower in frequency than the whales I had been working with.’

In fact, Parks discovered, modern North Atlantic right whales have shifted their calls up an entire octave over the past half century or so, in an attempt to be heard over the unending, and steadily growing, low-frequency drone of commercial shipping. Where right-whale song once carried 20 to 100 miles, today those calls travel only five miles before dissolving into the din. [Continue reading…]

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The risks that GMOs may pose to the global ecosystem

Mark Spitznagel and Nassim Nicholas Taleb, who both anticipated the failure of the financial system in 2007, see eerie parallels in the reasoning being used by those who believed in stability then and those who insist now that there are no significant risks involved in the promotion of genetically modified organisms (GMOs).

Spitznagel and Taleb write: First, there has been a tendency to label anyone who dislikes G.M.O.s as anti-science — and put them in the anti-antibiotics, antivaccine, even Luddite category. There is, of course, nothing scientific about the comparison. Nor is the scholastic invocation of a “consensus” a valid scientific argument.

Interestingly, there are similarities between arguments that are pro-G.M.O. and snake oil, the latter having relied on a cosmetic definition of science. The charge of “therapeutic nihilism” was leveled at people who contested snake oil medicine at the turn of the 20th century. (At that time, anything with the appearance of sophistication was considered “progress.”)

Second, we are told that a modified tomato is not different from a naturally occurring tomato. That is wrong: The statistical mechanism by which a tomato was built by nature is bottom-up, by tinkering in small steps (as with the restaurant business, distinct from contagion-prone banks). In nature, errors stay confined and, critically, isolated.

Third, the technological salvation argument we faced in finance is also present with G.M.O.s, which are intended to “save children by providing them with vitamin-enriched rice.” The argument’s flaw is obvious: In a complex system, we do not know the causal chain, and it is better to solve a problem by the simplest method, and one that is unlikely to cause a bigger problem.

Fourth, by leading to monoculture — which is the same in finance, where all risks became systemic — G.M.O.s threaten more than they can potentially help. Ireland’s population was decimated by the effect of monoculture during the potato famine. Just consider that the same can happen at a planetary scale.

Fifth, and what is most worrisome, is that the risk of G.M.O.s are more severe than those of finance. They can lead to complex chains of unpredictable changes in the ecosystem, while the methods of risk management with G.M.O.s — unlike finance, where some effort was made — are not even primitive.

The G.M.O. experiment, carried out in real time and with our entire food and ecological system as its laboratory, is perhaps the greatest case of human hubris ever. It creates yet another systemic, “too big too fail” enterprise — but one for which no bailouts will be possible when it fails. [Continue reading…]

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