Notes

Now, Zach, this is interesting paradoxical expression which I would like to investigate further. Please excuse me, for all of you who find this extremely unentertaining. When I say "expression," I mean a mathematical and/or scientific expression, not the expression which you probably thought that I meant.

So, if the "day of the day today is today," would that not also mean by contrast that the "yesterday of yesterday yesterday [was] yesterday"? If that was true, then the "tomorrow of tomorrow tomorrow [will be] tomorrow"

Because you posted this today, well, because I only saw it only 9 minutes later, this means that it is truly, "today." (with the exception of you posting it at 11:51pm or later). Unless you set a bot or other automated program to post the pre-written message at exactly 3:50:02 post-meridiem on the day commonly known as March 2, 2016 C.E., which was a Wednesday, in Eastern Standard Time (EST), which is in the time zone not-so-commonly known as UTC-5:00. I don't think that that is what happened.
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But what if I read it tomorrow? Should I read it as literally, "today", so "tomorrow" today (on said March the 2nd). Then, today, it would be read as "Day of the Day: Today," because that's what it says. The post won't change. But technically it would be: "Day of the Day: Yesterday". Or would it be, "Day of Yesterday: Yesterday". Furthermore, if "yesterday" was the day of the day yesterday, then even today (March 2) the day of the day would also be yesterday. If this was true, then this paradox would continue, going back until the beginning of time (which may in itself be non-existent; a different paradox which I am perfectly willing to discuss or debate with anyone who is interested, but not in this post).
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That being said, "yesterday of yesterday yesterday [was] yesterday" (if you were to analyze this statement through an analogy), would also be a paradox of multiple time continuums going back to the possibly non-existent beginning of time. This is due to the fact that if today (March 2), I read the word, "yesterday," which as example was also posted today (March 2), then this would continue for every day for the rest of time (also possibly non-existent; that is, the end of time being non-existent). The tomorrow of today (March 3 and March 2, respectively) would have the same effect. But what if I looked ahead to the future of tomorrow. Because tomorrow (March 3), yesterday would be what we call on March the 2nd today. But "yesterday" is still the "Day of tomorrow/yesterday/today (in this case it is irrelevant). So, we conclude that using this given formula, by looking to any day in the past or future, the Day of the Day/Yesterday/Tomorrow can actually be any given date going back to the possibly non-existent beginning of time.

But what about "tomorrow of tomorrow [will be] tomorrow"? Well, I suppose one could say that we have to wait until tomorrow to find out, but even then, because the post as well as its sub-analogies will remain the same, the same "yesterday" paradox will remain in place, except for that it will be going in the opposite direction (that is, the future, as opposed to the past). Again, if we look ahead to the "tomorrow" today (March 3 and March 2, respectively), we will find that we can even create a link to the day after that, because, after all, we are still living and creating these paradoxical formulas in the present, aka, today. This can continue to any day in the future.

Now, enough of my ranting. Tomorrow I can explain further. When you read this tomorrow, you will find yourself in an interesting paradoxical dilemma in which I can claim that tomorrow is the past. I don't think you'll be able to figure this out anytime soon, but for the second time yesterday, enough of my ranting.