Favourite Numbers - Numberphile
Why Mathematics Stack Exchange recommends it
Mathematics Stack Exchange askers cite it as the source when they want to know what Vi Hart's "star" and Henry Reich's "j" actually are.
Recommended by 0 people across 0 different months, 2012 to 2017.
What it is
A 2012 Numberphile video in which Brady Haran collects favourite numbers from popular YouTube educators, including Derek Muller, Hank Green, Michael Stevens, Henry Reich and Vi Hart. Choices range from i, 0 and 1729 to more exotic picks like the combinatorial game number star and the split-complex unit j.
What people said
Cites Asinomás · 2012-11 · Mathematics Stack Exchange · on “What does she mean by star?”
I was looking at this video [this video] and i wondered what she means by star. How is this number defined and where does it come up. Thanks in advance.
Cites Cisplatin · 2013-04 · Mathematics Stack Exchange · on “Less than all positive numbers, greater than all negative numbers, and not zero; what is $\ast$?”
A part two, you could say, of my previous question [LINK] . I was watching a Numberphile video about the favorite number of some mathematicians, and at one point, the creator of ViHart said the following - Star. Which, it's not a number. It's like a number. The thing is, it's smaller than all the positive numbers, and it's larger than all the negative numbers. But it's not zero. It gets confused with zero. This is one of those weird things you get in combinatorial game theory, and, I like it. I think the very non-numberness of it, I think that's what appeals about a lot of these numbers. The video itself can be found here [this video] . I've searched the internet for anything about star, or $\ast
Cites Cisplatin · 2013-04 · Mathematics Stack Exchange · on “$j^2 = 1$, but $j \neq \pm 1$; what is $j$?”
I was watching a Numberphile video about the favorite number of some mathematicians, and at one point, the creator of MinutePhysics said the following - Similar to the way that $i$ is $\sqrt{-1}$, but what that actually means is that $i^2$ is $-1$, $j^2$ is $+1$, but $j$ is not $1$. Here's the video with him saying all this - [this video] I've searched the internet for anything about j, but this video seems to be the only place where $j$ is mentioned. Does $j$ exist? If so, can someone explain what $j$ is? Or is this whole $j$ thing just a joke?
Cites Shaun · 2017-11 · Mathematics Stack Exchange · on “Numberphile: Vi Hart's favourite number, $*$. What is it?”
I apologise if this is a duplicate in any way. I couldn't find anything here. In this [this video] Numberphile video at about six and a half minutes in, Vi Hart chooses the "number" $*$ as her favourite number. She says it's less than all the positive numbers and greater than all the negative numbers, but is not zero. What is a formal definition of this "number" (if the above doesn't qualify as one)? She says it's used in Combinatorial Game Theory. What is it used for exactly?