Project 6: Randomness
Randomness, the lack of a definite pattern or predictability, is usually undesirable in scientific inquiries. Often it poses a nuisance to be overcome by repeated measurements and statistical analysis; in some cases (e.g., at atomic and subatomic scales governed by quantum mechanics), it is an essential property of the system, setting an insurmountable limit to the predictive power of our theory. Nevertheless, randomness in the genetic machinery of neurons has been ingeniously exploited with stunning effects.
Brainbow labeling of neurons
Fluorescent proteins have revolutionized biology, as they enable researchers to visualize cells and tissues of interest with specific labeling. However, each “cell type”, defined by a common pattern of gene expression, comprises many cells, which are often packed too densely to be visualized clearly. Labeling each cell with a distinct color would solve this problem, but there are simply not enough variants in the palette of fluorescent proteins to do so.
To solve this conundrum, a group of neuroscientists led by Dr. Jeff Lichtman at Harvard University came up with an ingenious idea. They realized that one only needs three kinds of fluorescent proteins to generate many colors, just as the three primary colors (red, green, and blue) can be mixed to yield millions of colors in movies and televisions. However, as cells belonging to the same cell type share the same gene expression pattern, how can they be coaxed into expressing these fluorescent proteins in different proportions?
The researchers took advantage of the intrinsic randomness of genetic machinery. They made DNA constructs encoding different fluorescent proteins (for example, red, yellow, and cyan) and inserted them into the mouse genome. The expression of these proteins may be turned on or off, depending on the action of an enzyme (Cre recombinase). Notably, the transgenic mouse genome encodes multiple copies of each fluorescent protein, but whether a particular copy is expressed or not is random in any cell. The net effect is that each cell expresses a distinct mixture of red, green, and blue fluorescent proteins and exhibits a unique color.
Randomness in art
Artmaking is a deliberate process. We typically envisage an artist judiciously materializing a vision into a physical form – chiseling a piece of marble into a sculpture or meticulously rendering a three dimensional horizon onto a two dimensional canvas. This view of art creation emphasizes the artist’s intentional, conscious control over the materials to create an aesthetic object. Randomness, on the other hand, is by definition unpredictable and uncontrollable. It seems to be at odds with the purposefulness of artmaking. Paradoxically, many artists deliberately embrace randomness either as a medium itself or as an essential ingredient of the final product.
Jackson Pollock, the abstract expressionist painter, for instance, is famous for his "drip" paintings. By splattering paint onto the canvas, Pollock introduced an element of chance into his work. While his actions were deliberate, the outcome was inherently unpredictable. Once the paint left the brush, where it would land on the canvas was no longer controlled by the artist’s hand. The random outcome resulted in surprising, often unplanned effects.
In other cases, randomness is not merely a tool to facilitate art creation but a central component of the artwork itself. For instance, Fred Whipple, an American astronomer, created a series of "stochastic paintings," which he defined as compositions created through random processes. He asked whether creativity, self-expression, or beauty could emerge from randomness. He proposed that stochastic art should follow rules governing randomness. Importantly, Whipple distinguished between randomness and mere irregularity. He explained that within an aggregate of random numbers, colors, or distributions, structured patterns would naturally arise and lead to something that appears ordered, not mere chaos. To create his paintings, Whipple selected random numbers and applied a set of rules to choose shapes, shades, and colors, embracing randomness to yield structured yet unpredictable compositions.
Jean Arp, a Dadaist painter, sculptor, and poet, famously incorporated chance into his art by tearing up pieces of his own drawings and allowing them to fall onto the canvas, preserving their landing spots. He was among the first artists to use randomness as a fundamental element of his work, treating chance as a collaborator rather than a limitation. By relinquishing control, Arp challenged the notion that artistic skill required precision and intent, instead embracing unpredictability as part of his creative process.
Randomness can also emerge from the material itself. For example, traditional Chinese ink painting commonly uses the rice paper (Xuanzhi), because its texture allows for “the writing brush, wet with Chinese ink and held in a well-trained hand, to move freely on it, making strokes varying from shade to light, from real to imaginative.” The ink spreads and diffuses on the rough surface of the rice paper, The choice of a rough surface in ink painting introduces an inherent randomness to how the ink spreads across the canvas. The unpredictable spread becomes an integral part of the artwork.
