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Tyrannosaurus

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Title text: Many of the smaller dinosaurs seem to have largely preyed on housecats.

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Explanation

This comic is a play on artistic reconstructions of dinosaurs. Generally, in order to allow viewers to get a concrete idea of the size of the creature, a easily recognizable and sizeable being, like a human or a cat, is placed next to the object, for scale. The scientists studying these pictures, however, seem to have come to the conclusion that the for-scale-creature and the dinosaur were actually in the same environment. This would make the former an easy target for the dinosaur, and hence good prey.

The title text is an extension of the misconception to smaller dinosaurs. Humans have had lots of contact with housecats,^{[citation needed]} so a cat would serve as a good scale comparison in reconstruction of such a dinosaur.

Transcript

[Miss Lenhart points at a poster which has two lines of illegible text above silhouettes of a Tyrannosaurus rex and a human.]

Miss Lenhart: We now believe the primary prey of Tyrannosaurus rex was these humans who kept standing next to it for scale.

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This Week's Explanation for Improvement

As part of the Explanation Improvement Project, each week the community selects one older, neglected, or otherwise stagnant explanation to expand and polish together. This week's pick is comic 395: Morning; help us by editing its explanation!

To get involved with the project, you can also nominate an explanation that you think should be improved, or vote on current nominations!

Morning

|< < Prev #395 (March 12, 2008) Next > >|

Title text: I'd press on them to try to unstick them, but I can't reach. Can we try cycling day and night really fast?

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Explanation

Welcome to This Week's Explanation for Improvement! Anyone is encouraged to help explain comic 395: Morning; click here to get started! If you are new to wiki editing, you can read our editing FAQ for guidance. Here are some suggestions for improving this explanation:   Explain the references to The Matrix to someone who has never heard of the movie.   Explain the "screen resolution of the world" in first panel. Is there truth to this? What resolution do our eyes actually have?   Explain the title text, especially "cycling day and night really fast".   The explanation of LCD screens is too technical.

A close-up of the sky with the dead pixels, at the top of the frame, with trees for reference.

The three fake dead pixels in the comic (left) next to a couple of real fuchsia dead pixels (right)

This comic plays on the idea that physical reality might be a simulation running inside a supercomputer. This idea has been explored in popular culture, as mentioned in the comic itself, but the second panel argues the revelation would still be a deeply existential horror if it were true.

The first panel mentions The Matrix, a 1999 action movie where the main character Neo discovers that the world he thought he knew was actually a simulation being run by an army of robots, who keep the human race hypnotized inside the titular simulation. It is perhaps the most famous work of fiction to touch on the theme of reality being a simulation, and an easy cultural touchstone at the time this comic was written (thus Megan's claim "We've all seen" it).

The reveal of her reality being a simulation comes when she sees "dead pixels" in the sky. In LCD screens, especially TFT LCD, a dead pixel is a pixel that does not work properly, usually set permanently as black, or as some other color. LCD screens were a more common standard when this comic was written, but have largely been supplanted by LED screens wherever possible. Megan realizes that the reality is a computer simulation when she sees dead pixels in the sky, indicating that what she sees is an LCD screen. In the last panel of the comic, there are three pixels — two red and one green — that look exactly like actual dead pixels. Note that the trees are not pixelated, meaning that only the sky is a giant LCD screen.

Regarding the question in the first panel, "What resolution is life?" (by which "life" presumably means the "real world" or lived experience, not living biochemistry), the most scientifically meaningful response would involve Planck distance and Planck time, the smallest units of distance and time that time-space can be broken down into. These are the fundamental building blocks of the time-space around us, similar to pixels (picture elements) on a screen, or a bit (one-or-zero) of data. Datum. Data. Humans, of course, cannot perceive changes on that scale - our experience occurs at a much less fine-grained level, with the human eye having a resolution of about 576 megapixels.

The title text refers to common techniques for fixing a dead pixel. One way is to apply pressure and release it, which isn't possible for Megan due to the distance of the sky. Another is to make the area of the screen that the dead pixel is on change colors really quickly, which could happen if the day-night cycle was fast enough, or if the clouds overhead were sped up.

Transcript

[Megan is standing to one side.]

We've all seen The Matrix

We've all joked about "What resolution is life?"

But it doesn't blunt the shock

Of waking up one morning

[Megan looks up from field and sees several colored pixels in the sky.]

And seeing dead pixels in the sky.

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