T is not
often that a correction must be made to a poem. But when the subject
is the mercurial science of particle physics, that is the risk a
In 1960, when he was 28, John Updike published a literary
invention that is still read fondly today — not "Rabbit, Run," which
also came out that year, but 19 lines of verse, quietly unleashed in
The New Yorker, called "Cosmic Gall."
Neutrinos, they are very small.
They have no charge and have no mass
And do not interact at all.
The earth is just a silly ball
To them, through which they simply pass. . . .
There, in the second line of the first verse, is the error — as
laid bare last weekend in a joint meeting in Albuquerque of the
American Physical Society and the American Astronomical Society. The
ghostly particles are still understood to carry no charge, but
experimental results announced at the conference seem to have
clinched the case, building for years, that they are not entirely
It was a sad day for poetry. Somehow, "They have no charge and
little mass" just doesn't have the same ring.
In fact the next line of the poem had long ago been edited (to
read "scarcely interact at all") by the Nobel laureate Murray
Gell-Mann when he borrowed "Cosmic Gall" for a lecture. As
insouciant as neutrinos are, they do occasionally consort with their
Every particle — electrons, protons, photons, quarks — has a
unique personality. The neutrino, which began in 1930 as a
half-baked idea, has simply matured. When heavy particles called
neutrons decay into protons and electrons, the energy going into the
process doesn't equal the amount coming out — an impossibility.
Hence the Austrian-born theorist Wolfgang Pauli was moved to propose
that the reaction also emits evanescent little things that
conveniently make up the difference. The neutrino ("little neutral
one") was born, and christened by Enrico Fermi.
In later years, physicists went on to adopt a more whimsical
style of nomenclature (quarks, gluons). Had the particles' debut
been postponed a while, they might be known as wisps. They cannot
carry any electrical charge, for that would mess up the equations.
And until recently there was no reason to think they had any mass at
These qualities made the elusive particles — "Pauli's
poltergeists," they were sometimes called — almost impossible to
detect. ("They snub the most exquisite gas,/Ignore the most
substantial wall.") If the earth is just a silly ball to them, how
do you catch one in a trap?
It wasn't until 1956 that two experimenters, Frederick Reines and
Clyde L. Cowan Jr., figured out how. Perhaps that is when Mr. Updike
first heard of the things. Neutrinos, it appeared, were real after
all. Soon they became a favorite among science writers, who came to
the subject with a roster of adjectives so obligatory it sometimes
seemed that each had been assigned its own word-processor key. (Four
of them — ghostly, insouciant, evanescent and elusive — have already
been used up in this article.)
Pouring from the sun, the equations predicted, trillions upon
trillions of the fleeting particles should slice through the earth
("Like tall/And painless guillotines") every second. Hoping to snag
a few with their detectors, experimenters lurked inside mine shafts
and tunnels, places only neutrinos could penetrate.
When the results came in, theorists were astounded to learn that
the sun was emanating only about a third of the neutrinos it was
supposed to. Scrambling for an explanation, some ventured that there
must be a black hole in the middle of the sun, gobbling most of them
up. Or perhaps, another proposed, the sun had already burned out,
stanching the neutrino flow. So dense is the solar core that
photons, the carriers of light, take millions of years to find their
way to the surface. Evidence of their decline would be delayed for
eons. But once the nuclear furnace began to cool, the flux of
unstoppable neutrinos would drop off immediately — a warning of
darker times ahead.
What has become the favored explanation was clinched last week at
the meeting in Albuquerque. Over the years physicists have
determined that there are actually three "flavors" of neutrinos.
Maybe on their way to the earth, most of the plain vanilla ones —
the kind the detectors can most easily spot — turn into chocolate or
raspberry. That could only happen, the theorists say, if the
particles have mass.
Last summer, the Sudbury Neutrino Observatory, located at the
bottom of a Canadian nickel mine, 6,800-feet deep, reported that its
new detector — designed to register all three flavors — seemed to
have accounted for the missing particles. The latest, more refined
results, raise the scientists' certainty to 99.999 percent. (Had
they not stolen their own thunder with the earlier announcement,
this would have been even bigger news.)
EXPERIMENTS like these, done purely for the intellectual thrill,
have a beauty all their own. Donning helmets with Cyclopean lights,
physicists crowd onto a clattering elevator for the daily commute
down the mine shaft. Exiting at the bottom, they trudge through the
rocky corridor leading to the detector.
The brightly lit subterranean lab looks like something from "The
Andromeda Strain." Suspended inside an artificial lake 10 stories
deep, a large acrylic sphere holds a thousand tons of a substance
called heavy water (the hydrogen atoms have been beefed up with an
extra neutron in their cores). Surrounding it is a Fulleresque
scaffolding supporting 10,000 squinting electronic eyes. Day by day
they wait for a neutrino speeding through the earth to collide with
a heavy hydrogen nucleus.
The result is a tiny flash called Cherenkov radiation, a wink of
light sparked by a traveler from the center of the sun.
Someone should write a poem about it.