Ceci n’est pas une calculatrice

17.18, Thursday 18 Feb 2021

The main calculator I have on my phone is PCalc. It is worth every penny.

PCalc has also been going a super long time. The first version came out in 1992.

Here’s the announcement of PCalc’s release, reproduced on the developer’s blog:

Subject: [*] PCalc 1.0 Submission

Enclosed is a binhex file containing a submission for your archives. PCalc is a neat simulation of a programmable scientific calculator.

I can’t get this out of my head. Is it a calculator? Or is it a simulation of a calculator?

Something similar comes up when I’m reading to my toddler. We’ll be pointing things out in a book, she’ll be like “lion,” “table,” and I’m thinking sure, a picture of a lion, a picture of a table, we’re all good. And then there’s a picture of a picture, framed on a wall in the book, and she says “picture” and I’m like: Um, the whole page is also a picture, I lack the necessary information to disambiguate where you’re pointing here. Your finger is pointing with x and y coordinates, but additionally we need an r coordinate to indicate the level of reality being pointed at; are you pointing at the picture in the inner reality of the page, or the picture in the outer reality which is the page? Both are pictures, but we need to be precise here.

We need to distinguish because the consequences are profound. Here’s why:

A simulation inside reality cannot leak out. Characters don’t come out of the books I read (I assume).

But a simulation nestedinside a simulation is still a simulation. When I play cards inside Red Dead Redemption, I’m not playing a simulation of cards. I’m just playing cards.

To go back to my toddler’s book: framed art on the wall of my room stays within the frame. But framed art in a picture book can do anything the book’s author desires, including mixing with anything in the inner reality of the book.

So what if our universe is a simulation? Then any and all simulations in our world - books, movies, computer graphics in GPUs - are all at the same “level” of reality as us. They can, potentially, leak.

Which I feel should be measurable and detectable in some way? If we live in a simulation, then a dense store of other simulations, fictional narratives even, say for example a library or a Netflix datacentre, should have a distorting effect on local physics. Which would be noticeable, in theory, by building an extremely large and sensitive particle collider and looking for deviations.


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