Its about a certain form of reinforced learning, called Temporal Difference Learning:

https://inria.hal.science/hal-00840470/document at page 11.

The calculation is called simple because it follows directly from the definitions above. Simple means more like "follows directly from definition without fancy math tricks", not " everyone who can read could solve this in 10 minutes".

I think this is also mostly math related, not physics?

I had a good laugh anyway. Good meme

Same feeling

I work in documentation. We aren't allowed to use words like "simple" or "easy" precisely for this reason.

"We can trivially show that...'

Turns out, after a page of algebra, it wasn't "trivial".

That particular line looks like application of some rule or substitution of a term - on it’s own, simple

This trivial result is left as an exercise to the reader.

We should have never given physicists the alphabet.

"Just a simple chord:"

plays Through Fire & Flames

That's what my son's homework from university looks like. I've done the same stuff about 35 years ago, but as I never used advanced algebra and analysis for my job, I've basically forgotten most of it.

At least I know roughly what my son is talking about. My wife (language teacher of German and English) is completly lost.

My Casio watch calculator has none of those symbols so I don't think it is so simple.

Math majors: "Duh."

Non-math majors: "And then a miracle occurs..."

My calc professor would say that stuff and be absolutely giddy despite rows of barely adults with confused faces looking at him.

Whoever wrote that, could have taught law school with that kind of irony.

(“Brief” my ass.)

I think it says "simple" as due to not discourage the reader, 'cause it's probably a simple substitution in context which just looks complicated at first glance.

Thanks. You just gave me flashbacks to my college classes. I felt a shudder run down my spine

Stochastic differential equations?

To be fair, it looks simple compared to really difficult stuff