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In which Hank and John, in their final reunion video for now, discuss the facts that blow their minds--from the lack of time before the Big Bang to the astonishing newness of recorded music.
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Book club:
John: Good morning Hank, it's Tuesday. Oh look, it's Hank's book "An Absolutely Remarkable Thing" which he wants you to know is available at fine book stores everywhere.

Hank: Has been since 2018.

J: Hank, today we're doing something called 'Mindblowers with Hank and John', where we share with each other the most mind-blowing facts that we know.

H: *distressed groan* Okay.

J: Okay Hank, here's my first fact: pi calculated to the 38th digit is precise enough to calculate, uh, assuming that we knew all the other numbers, the size of the Milky Way galaxy to within a few centimeters. So like, we only need to know pi to the 38th digit, but we know pi to the 31-trillionth digit.

H: *wheezes* That's not a fact about Pi, it's a fact about humans

J: We're amazing!

H: Yeah.

J: I can't get enough of us!

H: I read a few years ago that there are probably fragments of dinosaur bone on the moon. The asteroid that killed the dinosaurs probably shed debris as far as Jupiter. Another great, mind-blowing fact is that some science communicators figured out that bananas were a really good system for the scale of radiation.

J: How so?

H: They have a little bit of radiation in them. And so, like, eating one banana exposes you to some radiation. So you wanna know how much radiation you get, like, flying in a jet airplane to Europe, you can do it in bananas.

J: Now I'm gonna have to Google how many bananas an airplane flight is to find out if it was worth it to come here to visit you.

H: *wheeze*

J: Here's a mind-blower that Hank taught me: "Before the Big Bang" is an incorrect idea because, in addition to creating space as we now understand it, the Big Bang created time as we currently understand it?!

H: Yeah, no. Absolutely. To me, the mind-blowing fact is that you can look up into the sky with a telescope and see the Big Bang. Here's a great one. Henry Rice (?) told me this: If the universe were infinitely big and infinitely old, the night sky would be white.

J: Why?

H: Because there would be light from all of the stars in every direction. There would be no space not taken up by stars because the universe would be infinitely big and infinitely old.

J: *mind actually explodes*

J: Okay Hank, here's one that gets me: for 99.99% of human history, you could only hear music if you were within earshot of someone who was making it.

H: Yes.

J: And the idea of an album of recorded music is younger than Dr. Pepper.

H: *wheezes*

H: We do not know why there is matter.

J: What?

H: And we do not, in two different ways. One, we don't know why there wasn't an equal amount of anti-matter and matter created and so everything annihilated itself. 

J: Like the Big Bang, it should've just been, like, Even Steven -- 

H: Smoop. Yeah.

J: -- it Big Bangs and then it Big Smoops.

H: Well, and then just like, space and time continue to bang, but matter does not. According to our understanding of the universe, a universe without matter is just as likely, if not more likely, than a universe with matter. And then, like, separately from that, we don't know why matter exists at all.

J: So, we don't really know why I'm here...?

H: Oh, definitely not.

J: Okay.

H: On, like, way more levels than just those two.

J: Right, like, we don't know why I'm here in the sense that like, we don't know why the atoms that are inside of me exist.

H: Yeah. It'd be interesting to look at what makes a fact mind-blowing. 

J: I think it's when it makes me feel either big or small. When it re-contextualizes my understanding of myself and my place in the universe.

H: Yeah. Like, I want to understand my own emotions because ultimately, I am the most interesting part of the universe.

J: I would argue that I am.

H: *wheezes*

J: It's you not wake up in the morning and your first thought is of me and my needs?

H: Some days, when it's a really bad day...

J: Yeah.

H: ... I do think, "Well, we are on a little infinitely tiny speck."

J: Yeah. On the one hand, it's that feeling of wonderful smallness, which you would think would be sad, but isn't. But then on the other hand, there's the feeling of, like, "Well there might not have been in that sense, I am quite something!" This whole thing is weird...thank you for coming to my Ted Talk.

H: *wheezes*

J: Hank, I'll continue to see you right now.