It’s not because they say bazinga.
Since The Big Bang Theory’s beginning, fans have likely noticed Sheldon Cooper’s shirts. When they’re not confused by his latest argument about cow-tipping physics.
Like the rest of the characters, Sheldon has hobbies and interests which lean towards nerdy. This includes superheroes from DC Comics. Superheroes have become hugely popular over the past decade, as anyone might have noticed. So, it makes sense Sheldon would have shirts related to them.
They achieve impossible feats.
But it’s not just the shirts. Sheldon’s favorite gaggle of heroes make complete sense for a physicist to like. His central trio consists of The Flash, Batman, and Green Lantern. All three of these characters apply some method of science, physics, and brainpower to overcome obstacles.
For instance, Batman is notorious for a lot of things. Defeating his rogue’s gallery, solving crimes as the world’s greatest detective, dancing. Batman achieves this by applying his monumental wealth and mind to address each problem he comes across.
Whether testing samples at the bat lab or tracing criminals with scientifically amazing equipment, Batman is a smarty-pants at heart.
Speed is all relative.
Sheldon loves Batman for all the applications of science. But The Flash is like living science. If you aren’t familiar, Flash moves fast. Really fast. And if you obey comic book logic and accept all of it as canon, Flash can run in attoseconds. That’s incomprehensible speed.
Sheldon is like The Flash. He’s incomprehensible! But in all seriousness, Sheldon is a quick thinker. And to boot, Sheldon likely respects the power potential of superhuman speed. Time and space are intertwined with how fast an object moves, which is a scientifically complex subject. The debates and topics about it alone are enough to make Mr. Cooper giddy.
Mind over matter
Finally, comes Green Lantern, a character whose power comes from a ring and sheer will. Green Lantern creates objects of basically anything by focusing on them. It’s like a scientific principle: you apply your mind, and you get results.
No character understands this better than Sheldon. As a scientist and resident must-always-be-right-guy, Sheldon tackles solutions with willpower and his mind. Just as well, the capabilities of creating any object from sheer thought alone are fascinating to a scientist.
The power of science.
It’s no surprise Sheldon’s shirts are a reference to something scientific. Heck, you can catch him sporting one with a double helix or math equation sometimes. But his hero choices are sensible, as they embody some of the strongest points about scientific discovery and use.