“An ideal body is now defined, called a blackbody ...the blackbody is a perfect absorber... ” -Robert Siegel and John R. Howell, Thermal Radiation Heat Transfer; Volume 1
A body can be perfectly black meaning it absorbs all radiance—all heat and light waves that fall upon it. A blackbody is perfect because it is a perfect absorber—all waves that strike its surface pass into the body and the body absorbs them internally. Nothing striking the blackbody passes through the body’s edge. Nothing striking the blackbody is reflected back into the environment. The blackbody is perfect. It is opaque. It is not defined by its size or shape. It might not be black at all. The color black absorbs all wavelengths of light that fall upon it. The blackbody is named for its presumed blackness to the naked eye but a blackbody can be red or blue or another color. The blackness is theoretical. The blackbody is theoretical—a device used to give body to abstractions. Perfect black is a theoretical ideal—it has not been observed but exists for the sake of comparison. For the sake of comparison, the opposite of a blackbody is a white body. A white body reflects all waves perfectly in all directions. The white body is also an abstraction that exists for the sake of comparison. The albedo scale compares white bodies and blackbodies. Albedo comes from Arabic’s albayad. Albayad roughly translates to “whiteness”. In physics, albedo is a measure of reflectivity and brightness. Scientists say the albedo effect is warming our planet beyond safety. Said another way, the whiteness effect is warming our planet beyond safety. 91% of Fortune 500 CEOs are white men. Outdoor air pollution has risen 8% in the past five years. The arctic is melting—the white ice is falling into the dark sea turning reflective surfaces into heat absorbers. It’s getting warmer. By “it’s getting warmer”, I mean that it was 129.2o in Iran last week. By “it’s getting warmer”, I mean that in 2010, 10,000 scorched to death in Moscow. By “it’s getting warmer”, I mean that by 2080, 3300 will scorch to death on the streets of New York City, and half of those buried will be black. It’s getting warmer and I wonder about white men in boardrooms. I wonder about the PowerPoint presentations and profit diagrams. On the diagram, the blue line is profit. The black bodies pile under the blue line over the axis of time and the blue line rises. In the boardroom, the black body is the ideal—we absorb perfectly.