Haven’t found this discussion. Mostly fragmented whenever it comes up.
A zero sum game is where one’s gain is another’s loss.
There are many markets for many instruments. Stocks. options, futures, forex, etc. There are many time frames, a few microseconds, an hour, a day, weeks, years, decades, etc.
It should be mentioned, the conventional wisdom is derivatives with expiration dates and cash settled often considered zero sum while equities are not.
So, in your opinion, is…