Cold (26 page)
The scientists did not share the commercial interests of the Ice King, Frederic Tudor. Instead, they saw themselves engaged
in a search for “the cold pole” and as surveyors working on “the map of Frigor.” They saw their quest as equivalent to those
of geographical explorers, of Columbus and Magellan and Cook, and of their contemporaries, the polar explorers Franklin and
Greely and Scott. Medieval mapmakers had once labeled unknown lands in the far north “ultima Thule,” and the scientists adopted
the phrase. Heike Kamerlingh Onnes, who would liquefy helium in 1908, wrote, “The arctic regions in physics incite the experimenter
as the extreme north and south incite the discoverer.” He was right in this assessment.
Like the Arctic explorers, the scientists were men obsessed. They often invested their own wealth. They gave up opportunities
for personal financial gain in exchange for opportunities to explore the frontiers of Frigor. They seemed to worry more about
an experiment failing than about the safety risk posed by laboratory explosions and fires. Onnes, in a letter to Dewar, was
concerned that “the bursting of the vacuum glasses during the experiment would not only be a most unpleasant incident, but
might at the same time annihilate the work of many months.” They had bitter rivalries, arguing over who reached the record
low temperatures first, who was first to liquefy this gas or that gas. Frustrated when he realized that Onnes had won the
race to liquefy helium, Dewar dressed down a senior assistant, blaming him for delays. The assistant vowed that he would never
set foot in the Royal Institution as long as Dewar lived and then held true to his word.
These men, these explorers of Frigor, worked brutally long hours, conducting single experiments that could run from before
dawn to late into the night, with laboratory assistants scurrying about, checking gauges, turning wheels that in turn spun
threaded bars that in turn compressed gases. They opened valves, and — when things went well, when nothing broke or jammed
or exploded — they transferred fluids such as liquid nitrogen, liquid oxygen, and liquid hydrogen from one vessel to another.
They were not above theatrics. In 1899, celebrating the hundredth anniversary of the Royal Institution, Dewar lectured to
an audience of dignitaries and scientists. The men wore frock coats, and the women wore formal dresses. Dewar played with
liquid oxygen. The men and women watched thermometers scream downward. Dewar liquefied oxygen before their eyes, turning a
clear gas into a blue liquid. He showed them how electrical resistance decreased as metals were cooled. There were lots of
tricks to be played near ultima Thule. Mercuric oxide went from scarlet to light orange. Rubber, ivory, feathers, and sponges
phosphoresced with their own bluish glow.
The scientists expected even stranger phenomena as temperatures dropped further. Dewar himself, speaking of absolute zero,
said that “molecular motion would probably cease, and what might be called the death of matter would ensue.”
But absolute zero was unattainable. Reaching absolute zero can be likened to reaching the speed of light: as one approaches
light speed, acceleration becomes increasingly difficult, and as one approaches absolute zero, further cooling becomes increasingly
difficult. A simpleminded and not altogether wrong explanation: at very low temperatures, any attempt to remove more heat
generates heat. But science is closer to absolute zero than to the speed of light. Science is within billionths of a degree
of absolute zero, within spitting distance of ultima Thule. Things have become increasingly difficult and increasingly frustrating,
and the death of matter, in a sense, has ensued.
If one ignores Drebbel’s stunt at Westminster Abbey, the race toward absolute zero started in earnest in 1748, when the Scottish
medical professor William Cullen used a vacuum pump to suck down the pressure of one vessel, cooling it sufficiently to freeze
the water in a surrounding, outer vessel. He published the work in a Scottish journal under the title “Of the Cold Produced
by Evaporating Fluids and of Some Other Means of Producing Cold,” but he took it no further. Almost a hundred years later,
cascading was developed, in which vaporization of one liquid cools another gas sufficiently to create a second liquid, which
is in turn vaporized to cool another gas into a liquid state, and so forth and so on. Another trick involved the expansion
of gas through a valve, allowing gas molecules to spread out without performing work and therefore to cool, taking advantage
of what physicists know as the Joule-Thomson effect. At this point, still well above absolute zero, the men exploring toward
ultima Thule were working at dangerously low temperatures, in a realm that left metal brittle and instantly froze flesh.
Helium was an important prize. In July 1908, starting before dawn, Heike Kamerlingh Onnes cascaded chloromethane to liquefy
ethylene, liquid ethylene to liquefy oxygen, liquid oxygen to liquefy air, and liquid air to liquefy hydrogen. It had taken
him seven years to prepare for the experiment. At seven o’clock in the evening, thirteen hours after the experiment began,
Onnes became the first human being to see liquid helium. “It was a wonderful moment,” he later recalled. Helium goes from
gas to liquid at 452 degrees below zero Fahrenheit, less than seven degrees above absolute zero.
Below the temperature of liquid helium, cascading and the Joule-Thomson effect are of little value. Things become increasingly
peculiar. For Onnes and his colleagues, trained in classical physics, the properties of matter no longer made sense. Even
calling liquid helium a liquid is not quite right. It is more of a superfluid, a phase of matter that behaves something like
a liquid but that has almost no viscosity.
Albert Einstein weighed in. Working with the Indian physicist Satyendra Nath Bose, Einstein realized that quantum physics
was at play. In the quantum world, atomic motion occurs in incremental steps: it is as though you can travel at one mile per
hour, five miles per hour, or ten miles per hour, but not at three miles per hour or four and a half miles per hour or seven
and a quarter miles per hour. Bose and Einstein realized that at extremely low temperatures, the wave functions that described
individual atoms would overlap. The wave functions would then merge, and groups of atoms would behave as one. In 1924, Bose
and Einstein proposed that a new state of matter would exist at extremely low temperatures. This state of matter — not gas,
not liquid, not solid — became known as the Bose-Einstein condensate.
It took sixty years to develop the technology to knock off those last couple of degrees on the road to the Bose-Einstein condensate.
By then, both Bose and Einstein were dead. In the quest for ultima Thule, new tricks had been discovered. When light hits
an object and is absorbed, the object is warmed, but when light hits an object and is reflected, it is cooled. With lasers,
pure wavelengths can be generated and reflected off a packet of atoms. In 1995, Eric Cornell and Carl Wieman used lasers to
cool a packet of rubidium atoms to ten-thousandths of a degree above absolute zero, to the point at which molecular motion
almost stops. “It’s like running in a hail storm so that no matter what direction you run the hail is always hitting you in
the face,” Wieman said. “So you stop.” It was still too hot for a Bose-Einstein condensate. To cool their rubidium atoms further,
they used what in principle is the same trick used by their nineteenth-century forebears — a form of evaporative cooling,
allowing the most energetic atoms to escape and leaving only the less energetic and cooler atoms behind. “It’s the exact same
physics as how a cup of coffee cools,” Wieman explained during a 2001 press conference. “The steam coming off is the most
energetic coffee atoms. The ones left behind get colder.” In the end, the rubidium had cooled to something like fifty-billionths
of a degree above absolute zero, or just shy of 460 degrees below zero Fahrenheit. And the atoms were no longer a gas or a
liquid or a solid. In a brand of alchemy that would have made the likes of Cornelis Drebbel cackle in glee, the kind of matter
known to men such as Dewar and Onnes and Boyle had died, and what was left was a Bose-Einstein condensate — a thick glob of
about two thousand atoms condensed into a single super atom surrounded by warmer atoms, reportedly looking something like
the pit inside a translucent cherry made of a glowing cloud of very cold rubidium.
It is February twentieth and forty-one below in Fairbanks — 419 degrees Fahrenheit above absolute zero. True to form, the
cold has returned to Alaska. Frigid air hitting cold lungs makes me cough. My parka is stiff. Its fabric complains when I
move, screeching softly, retaining wrinkles, holding its shape, its molecules locked up as if close to ultima Thule. My rental
car was parked outside overnight, and its tires have frozen out of round. As they thump down the road, I bounce up and down
as if driving a Mack truck. Outside, I pull on my hood. I hunch my shoulders and walk with my head down. Today, forty-one
below leaves me grumpy and withdrawn.
In my hotel, the International Arctic Research Center has teamed up with a consortium of Japanese universities to hold a conference
on global warming. The language barrier makes conversation all but impossible. From what I can gather, there is concern that
melting permafrost will crack foundations and cause sags in oil pipelines. A German meteorologist argues with a Japanese glaciologist
in three languages. They wear name tags in plastic holders strung from their necks. Within this meeting room, to a degree
seldom seen elsewhere, there is a realization of the extent of the world’s permafrost and the threat of a warming planet.
There is a realization that permafrost will melt in Alaska and Canada and northern Russia and Norway and in the mountains
of Tibet. The same warming that will compromise a trapper’s cabin in the Alaskan bush will fracture a thousand-year-old Buddhist
temple in the Himalayas.
No one goes outside. For scientists, it is too cold to go outside.
Front-page news in Fairbanks focuses on the thousand-mile Yukon Quest dogsled race. Lance Mackey, having made it to the Chena
Hot Springs checkpoint late yesterday afternoon, is set to break the record. After a required rest stop, he has but ninety-nine
miles to go. He will likely mush into Fairbanks sometime early this afternoon, with a race time of just over ten days, beating
the 1995 record by half a day. These are tough races for both dogs and mushers. One of the athletes, a sled dog named Melville,
died close to the Yukon River. Another, named Jewel, died earlier in the race, choking on its own vomit. But the mushers do
not win races by merely riding along behind the dogs. The sleds have to be worked through drifts. They pound over rough snow
and ice. These are the trails of prospectors and trappers and Jack London, and before them of the Athabascan Indians, who
lived inland from the Eskimos, in Alaska’s brutally cold interior. On steep runs, it is not unusual for a musher to run along
behind the sled. Along the Yukon, they may run along in temperatures that hit seventy below, plus windchill. Photographs of
the mushers show their faces iced over, looking drawn, caring for one dog or another, hugging it or feeding it or working
the harness straps under the light of a headlamp.
On a back page, the Fairbanks paper talks of three climbers and their dog saved on Mount Hood, Oregon, hauled away in an ambulance
after spending the night huddled in the snow, like maladapted penguins. “We’re soaking wet and freezing,” one of the climbers
said. According to one of the rescuers, the dog, lying across their bodies through the cold night, likely saved their lives.
On the East Coast, discount air carrier JetBlue has just recovered, back on schedule a week after a snowstorm forced it to
cancel 139 flights. Closer to home, in Soldotna, a couple of hours south of Anchorage, officials estimated damage to city
property at more than one and a half million dollars, all of it linked to the short-lived but very real warm spell of the
week before, with its quick thaw causing flooding and the moving floodwaters carrying big blocks of ice, reminding everyone
of the temporary nature of human structures in Alaska.
And there is this in the newspaper: human egg donors are getting as much as eight thousand dollars from prospective parents.
More than ten thousand women donated eggs in one year. They used the money for vacations and college tuition and rent. Men,
too, are part of this economy. “Our main activity,” one company advertises, “is worldwide delivery of high quality frozen
tested semen from more than 250 donors.” Sperm are stored in liquid nitrogen at 320 degrees below zero. Once stored, sperm
can be kept indefinitely. It is reasonable to expect fifty percent survival even after hundreds of years. For eggs, freezing
is far more risky, but when women are threatened with various diseases that would otherwise end their ability to reproduce,
freezing can be an option. Reluctant parents could, in theory, freeze sperm and eggs for generations, have the sperm and eggs
joined long after they themselves are dead, and reproduce without the headaches of child rearing and babysitting. Perhaps
Fahrenheit and Boyle and Faraday would be mortified to know of where their research has led. Alternatively, perhaps they would
have masturbated into test tubes and stored their sperm in liquid nitrogen, to be resurrected as needed, little half geniuses
waiting centuries for a nice warm egg to inseminate.