I really like Max Tegmark because he bravely thinks about strange, but stll plausible things. He makes me think deeply and has so for many years.

But i have one BIG (to me) question. What exactly does it mean to say reality is a mathematical "structure"? I can't think of what such an implementation would actually be???

Is that a philosophical thing? Or a "spiritual" thing (in the hippie/zen sort of way)? Or a computer virtual instrumentality? Or elementary particles and so-called natural laws? I lean to the latter as the only one that strikes me as plausible. But I'm not the inventor of this idea, so, ask them.

As far as the "we're a computer simulation" argument I basically don't care a wit. As long as it seems real and plausible to me and it somehow allows "free will" (I don't know what that is either but DO care). I'm a cheer leader for DeCarte. I don't think his most oft repeated "cognito ergo sum" has ever been effectively
refuted. And as long as I can think (freely) I'm a happy camper.

But, I still like to think about it.