In December 1960, The New Yorker published John Updikes poem about the neutrino, a ghost-like particle discovered a few years before. Titled Cosmic Gall, Updikes poem examines the neutrinos bizarre properties. Little did he know how weird things would get: Scientists not only found two more types of neutrinos, but also discovered that the three types transform into each other. Here is a brief summary of what we know about the neutrino 40 years later.
Deconstruction: Cosmic gall
by Kurt Riesselmann
In December 1960, The New Yorker published John Updike's poem about the neutrino, a ghost-like particle discovered a few years before. Titled “Cosmic Gall,” Updike's poem examines the neutrino's bizarre properties. Little did he know how weird things would get: Scientists not only found two more types of neutrinos, but also discovered that the three types transform into each other. Here is a brief summary of what we know about the neutrino 40 years later.
by John Updike
Credit: “Cosmic Gall” from Collected Poems 19531993, by John Updike. Copyright John Updike.
|How small is small? The neutrino—one of the fundamental building blocks of matter—may have zero diameter. Why? The mathematical framework that describes the interactions of neutrinos, electrons, and other fundamental particles, known as quantum field theory, requires that fundamental particles be “point-like,” with no spatial extension. Experiments that try to find evidence for a non-zero diameter of fundamental particles such as quarks and neutrinos have failed so far. In contrast, composite particles are not pointlike. Protons, for example, are about 10-15 meters in diameter.|
|Neutrinos are the only fundamental building blocks of matter that have no electrical charge. The word “neutrino,” invented by Italian physicist Enrico Fermi, means “little neutral one.”|
|When Updike wrote this poem, scientists assumed that neutrinos had no mass. After all, early neutrino experiments never gave a hint that neutrinos might weigh something. But in the last 20 years, experimenters have found evidence that neutrinos do have mass and have begun to measure the differences in mass among the three types of neutrinos that occur in nature. Scientists also know from cosmological observations that a neutrino must be at least a million times lighter than an electron. But the exact weight of each type of neutrino remains unknown.|
|Do not interact at all
|Neutrinos hardly interact with other particles of matter. Saying that they do not interact at all is an overstatement. But poets are allowed to bend the truth a little, aren't they?|
|Through which they simply pass
|Neutrinos zip through matter like bullets through empty space. To them the Earth basically doesn't exist. Neutrinos from the sun enter Earth on one side and leave it on the opposite side about four hundredths of a second later, traveling along a straight line close to the speed of light. Fewer than one in a billion solar neutrinos traversing the Earth will interact with an electron or an atomic nucleus.|
|The most substantial wall
|To have a 50 percent chance of stopping a neutrino, scientists would need to build a wall of lead that is more than a light-year—or 9.5 trillion kilometers—thick.|
|Infiltrate you and me
|Stretch out your hand and count to three: a trillion neutrinos just streamed through your hand, yet you didn't feel a thing. The chance that a neutrino will interact with a single atom in your body during your lifetime is one in four.|
|Neutrinos come from fusion processes, such as the reactions that power our sun, and radioactivity, such as the natural decay of potassium inside a banana. Once they spring into existence, they travel close to the speed of light. Even though neutrinos have a tiny mass, Earth's gravity won't make them fall down.|
|The sun emits about as many neutrino particles as particles of light, which are known as photons. At night, Earth prevents the light from reaching us, but neutrinos continue to stream right through the globe and through our bodies.|
Click here to download the pdf version of this article.