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| Size and Lifespan |
 Title text: With their 13 years recording and performing together and two humans worth of mass, the White Stripes are sandwiched neatly between gray wolves and blue whales. |
Explanation
This comic presents a correlation between the size (in kg, therefore more accurately, the mass) of different objects with colors in their names, and their lifespan. It is similar to common charts that map the size versus lifespan of various animals, showing that, broadly, the larger they are, the longer they live, demonstrating biological allometry principles such as Kleiber's law. Here, however, it covers entirely unrelated classes of objects (animals, features of the Earth, and even astronomical bodies), appearing to suggest that there is some universal cosmic trend across all entities named with a color.
Black holes are complete outliers due to them (theoretically) being of many different sizes, and having a different relationship of size to 'life-expectancy', with evaporation through Hawking radiation making their effective lifespan scale with the cube of their mass. The subset of possible black holes that fit within the upper and lower time-scale limits of the comic (from the lower-limit origin of the graph out beyond the upper limit of the graph and all the way to the very top edge of the comic frame) therefore relate to a restricted subset of possible masses. The line widens towards the top, possibly to represent the uncertainty of mass for a given lifetime (and vice-versa) that may be due to the rate of accretion they can possibly undergo (to effectively extend their lifetime) according to their local environment. It produces a trend-line that is angled entirely across the general trend of all the other combined items.
Similarly, at either end of the scale, white blood cells and stars are 'smeared' across the chart. White blood cells are split into two different clumps (representing two separate types of white blood cell) which, together, 'cross' the general trend of the chart. The chosen spectrum of star types follow a continuous line, also crossing the general trend-line, which actually has an actual inverse slope (the more massive end of the line has a shorter lifetime than the least massive end), so can only tangentially support the basic premise of the rest of the graph, while demonstrating a departure from the more widely implied size/lifespan relationship.
The vertical (lifetime) axis starts from a single second at the bottom and ends at the top with the expected life-time of the longest lived stars (red dwarfs). The black holes still shown in the graph above the end of the time axis would therefore last a thousand times longer than those longest lived stars, which themselves are expected to last longer than the current age of the universe, so any black hole with a comprehensible life expectancy would be extremely small — just a few magnitudes more massive than a blue whale.
Somewhat dubiously, the chart conflates typical lifespans in some cases with lifetime to date in others.
| Object | Size (kg) | Lifespan (seconds) | Approx. lifespan (human-readable) | Explanation |
|---|---|---|---|---|
| white blood cells | 10-11±0.5 | 104.5±1.5, and 108.25±0.75 | 17 minutes–12 days, and 1–30 years | The graph separates memory lymphocytes (which need to be replaced only every few years) from the other kinds of white blood cells (which the body replaces every few days). |
| yellowjackets | 10-4±0.5 | 107.25±0.5 | 60 days–2 years | Example of a long insect lifespan |
| gray wolves | 101.5±0.5 | 108.5±0.5 | 3–30 years | Example of a typical mammal lifespan |
| blue whales | 104.5±1 | 109±0.5 | 10–100 years | Example of a long mammal lifespan |
| black holes | <105.5 to >1011.75±1.25 | <100 to >1025 | <1 second to >300 quadrillion years (20 million universe lifetimes) | Black holes eventually evaporate away due to Hawking radiation. 'Smaller' black holes can be surprisingly short-lived for celestial objects; however, this log-scale graph would have to be roughly four times taller to account for stellar-mass black holes (~1075 seconds, or >1057 universe lifetimes) and six times higher to account for the largest known black holes (over 10100 seconds, or >1082 universe lifetimes). Equally, the smallest theoretical black holes, which could be close to the Planck mass, would evaporate so quickly that to include them would require the chart to extend for about twice its current height below where it does. The smallest known black hole is roughly four times the mass of the Sun, meaning most of the line depicted covers ones that are only theoretical. The evaporation time of a black hole not fed is an easy formula. As the formula for evaporation time per mass is cubic, on a double-logarithmic scale this is a linear line with a gradient of 3:1. As the horizontal resolution is around half of the vertical, that makes it a visible gradient of 6:1, almost a vertical line. Once the black hole gets big enough, it is more likely to pull in new mass from the surrounding area and thus extend its lifetime before evaporating. Smaller black holes are too small to catch enough mass to make a difference, so the line is thinner at the bottom. That all black holes with lifetimes comparable to anything else familiar to humans have a mass between that of a blue whale and that of the red sea might be the joke that could have triggered the creation of this comic. |
| Red Sea | 1017.5±0.5 | 1015±1 | 3–300 million years | The time probably references the end of the desiccation of the Red Sea. |
| Greenland | 1020±0.5 | 1016.75±0.5 | 0.6–6 billion years | An autonomous territory of of Denmark, Greenland is the world's largest island. Greenland makes an interesting pairing with the Red Sea, because red is the opposite of green and sea is the opposite of land, a juxtaposition famously made by Rockapella that might have been internalized by Randall in his childhood and repeated here. |
| red dwarfs to blue giants | 1029 to
1032.5 |
1021 to
1013.5 |
1 million to 30 trillion years | Stars are probably some of the largest single things in the universe and often imagined to be longest-lasting, too. As can be seen on this diagram, though, many kinds of stars are more short-lived than some phenomena on Earth, like landmasses or seas. The inverse relationship between mass and lifespan (which goes against the overall suggested relationship of the chart) is because massive stars fuse hydrogen to helium far faster. The charted region is effectively an inverse of the famous Hertzsprung–Russell diagram, with the stellar classification (surface temperature) being inversely proportional to mass, and luminosity (rate of fusion) being inversely proportional to lifespan. |
| The White Stripes (title text) | 102 | 108.65 | 14 years | The White Stripes were a rock duo from 1997-2011 made up of Jack and Meg White. |
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