The atom was known to Victorian scientists, but what they visualized was quite different from what we imagine today. They thought atoms were lumps of sticky stuff like plum pudding, but bearing mass and a positive charge, both uniformly distributed throughout the atom. Embedded in this goo, like raisins, were just enough negatively-charged electrons to neutralize the atom’s overall charge. Matter, then was just a lot of these gooey blobs stuck together into a continuous mass, with little space between the atoms.
Around the turn of the twentieth century British physicist Ernest Rutherford, while studying the properties of radiation, found that the alpha particles emitted by some radioactive substances passed through gold foil unimpeded, as though it was not there at all. A random few, though, were deflected, as though they had ricocheted off of something solid. Is this the way a continuous wall of goo would behave? He doubted it. It would likely behave more like Uncle Remus’ Tar Baby, soaking up the alpha particles as the tar baby engulfed Brer Rabbit’s punches, so that very few of them would emerge at all. Instead the gold foil behaved like a sheet of nothingness with bits of something massive and immovable embedded in it.
In 1911 Rutherford introduced a new model for the atom, which rests more easily in the modern mind. He proposed that nearly all the mass and positive charge in an atom reside at an infinitesimally small point at the center, called the nucleus. The nearly massless electrons orbit about the nucleus somewhat like planets around the sun, though not confined to an ecliptic plane but rather in a sort of thin swarm. It followed from this that most of the volume of an atom is nothing more than empty space–there is nothing there that would deflect an alpha particle, unless it chanced to strike the nucleus. Matter, in this view, is mostly emptiness. Nothing really touches anything else. Science at the turn of the twentieth century kept growing weirder and weirder.
Salvadore Dali, the bizarre Spanish polymath and surrealist, was a connoisseur of wierd. He had a keen interest in the science of the atom as it was then unfolding . In particular, the notion of the illusion of solid matter, and of things which seem to touch yet never do, fascinated him. Especially in the period following World War 2, when Hiroshima had made atomic theory a matter of some urgency in the popular mind, these themes began to find their ways into his paintings. Among them was the 1949 painting, Leda Atomicus.
In Greek mythology Leda catches the eye of Zeus, who descends from Olympus in the form of a swan to seduce her on a night when she had already lain with her mortal husband. Following this coupling she produces two eggs, from which emerge the twins Castor and Pollux, Clytemnestra (wife of Agamemnon), and Helen of Troy. Some were mortal and some divine, although the myth gets a little fuzzy about which was which, as well as who shared which egg with whom.
In Dali’s painting Leda (modeled by Dali’s wife Gala) is sitting on a pedestal on a platform on a shore, embracing the head of a very excited swan. Close examinatio9n shows that her hand does not quite touch the swan, nor does her bottom quite touch the pedestal. In fact, nothing touches anything; even the sea laps a few inches above the sand, casting a shadow but not wetting it.
Philippe Halsman was a photographer who made his mark in commercial photography and portraits of famous people, many of which graced the cover of Life Magazine in its heyday. Halsman’s portraits are distinguished by a sense of fun and wit that is distinctly his own. He is perhaps best known for his portraits of celebrities jumping. The list is truly amazing: Princess Grace, Sophia Loren, Brigitte Bardot, Richard Nixon, Judge Learned Hand, physicist J. Robert Oppenheimer, theologian Paul Tillich, and the Duke and Duchess of Windsor, to name a few. One of these jumping portraits has developed a cult following of its own. Halsman called it Dali Atomicus.
This is so much more than a picture of an artist jumping. The artist is there of course, his feet not touching the ground. An easel before him likewise does not touch the floor or walls, nor does the chair in front of him. Water flows weightlessly across the foreground, distorting but not touching the painting he is working on. It is accompanied by cats. Everything interacts, but nothing touches. On the right is a painting of Leda Atomicus, floating in space, explaining it all.
People can be like that. We can all occupy the same house which, like Rutherford’s atom, is filled with mostly empty space. We orbit randomly without really touching, particles of emptiness, boredom, pain or joy, sometimes entangled with another particle, but mostly not. Unobserved, we occupy all of these quantum states at once, or none of them, or both all and none at once, like Schrödinger’s inscrutable cat. When we are asked, a single state declares itself: we laugh, we cry, we roar with rage, or scurry back into the shadows. The energy released from chain reactions that occur when a high energy neutral particle collides with us can power much that is good, but can also be immensely destructive. WIMPS are Weakly Interacting Massive Particles; are we all WIMPS? Is that why we call it a nuclear family?