The Hsieh Theorem 

Simply stated, the combination of any nationality with any noun can be used to construct a novel name for a sexual act.

Applications of the Hsieh Theorem resulted in the following names of sexual acts: the Italian oil change, the Greek photocopier, the Brazilian lawnmower ... and so on.

The Hsieh Theorem by Bisby February 15, 2010

Fedora Douchebag Threshold Theorem 

The sociological rule that one person wearing a fedora in a larger group may be stylistically unique, but two or more people wearing a fedora in a larger group renders every person in that group a douchebag.

Check it out - another fedora. What a douchebag.

No, wait - if it was just that one dude it might be cool, but two of his bros are wearing them too. According to the Fedora Douchebag Threshold Theorem, all five of them are douchebags.

Fedora Douchebag Threshold Theorem by CreditToJoe August 19, 2010

Theoretical bug 

When you discover that your code is not giving the right results, not because there is any bug in your program, but because there is a bug in the theory on which it is based.

Theoretical bugs are rare but more common than thought. When you find one, your perception of the world improves quantically.

A more day to day example, it is when you realize something you never saw before, not because it was not there, but because your mental model of the world didn't include it.

case 1
JC: I've been trying to find the bug in this program all night, but its looks perfect. Don't know why sometimes is producing weird results.
Guru: Its time to chase some Theoretical bugs.

case 2:

Linux_user: The problem with microsoft is not that they produced bad programs, but they copypasted so much software from other people, that the outcome was a walking Theoretical bug. At some much extent that, when it crashed it means it was really working.

Theoretical bug by jcmid February 5, 2010

Kalejs Theorem 

for one to digress from a topic so far that one no longer is speaking of anything of any relevance to the topic.

The Kalejs Theorem in practice; "Okay class today we are learning about electromagnetic radiation" (Proceeds to talk about volcanoes with the assistance of tools to find relevant videos)

Kalejs Theorem by me is a bomb 6969 May 10, 2021

The Theoretical Plate Standard 

The Theoretical Plate Standard (TPS) is the certified bro measurement of bigness. Also known as the 1234, such an achievement requires a 1 plate press, 2 plate bench, 3 plate squat, and 4 plate deadlift. Brothers who can certifiably complete this challenge, are defined by bros around him as "the big guy." lifting weights science

It's been two years since I've been counting my macros and I still haven't reached the theoretical plate standard; I might need to go on gear.

The Theoretical Plate Standard by Dnom March 28, 2019

Theorotic 

Being turned on by theories.

Becoming sexually aroused by the deeper meanings of life.

Damn bro, I got a hard on when Wonder Woman went all theorotic and explained Tetryonics!

Theorotic by Adrienne Adele July 3, 2017

Common Sense Theorem 

A mathematical and scientific hypothesis that proves any statement true using only the words "Common Sense".

"Given- Equilateral Triangle ABC has an area of 5 a height of 5, and a side length of x.

Prove- Triangle ABC has a perimeter of 3.

Step 1- Perimeter = 3
Reason- Common Sense Theorem"

While the above statement is impossible, the common sense proves it true.

Common Sense Theorem by Nately's Old Man June 2, 2011