Jim Fowler

@kisonecat.com

1112 Followers 1459 Following

associate professor in mathematics at The Ohio State University he/him https://youtube.com/kisonecat

Small black dots swirl around the screen as the vertices of a blue triangle are moved around. When the triangle is isoceles, the black dots line up along the axis of symmetry.
A sticker on a window that reads: MEMBER NATO National Association of Theatre Owners
A crumply paper sign that reads: ATTENTION Outage A Domestic Cold Eater outage will be required
A colorful bag of Cosmic Crisp apples, with the tagline at the top that says "amazing flavor + infinite possibilities". The bag features a big painterly image of an apple with three icons that mention snacking, baking, and entertainment.
The surface of an empty parking lot showing a few parking spots (outlined in yellow lines), part of a lamp post, and pools of water. The pools of water appear where the wheels of the car would be.
a blue box of Kellogg's VECTOR cereal, showcasing the texture of the flakes and its 13g of protein per serving. The words "HIGH PROTEIN" appear on the box. A man with glasses stands beside the box.
A poor quality image of Jupiter and its four moons. The background is black, and Jupiter appears as a large white circle, smeared out with a bluish halo. Tilted relative to Jupiter are smaller dots, the four Galilean moons.
Shorthair tabby cat curled up in off-white and blue-grey blankets
A framed piece of US letter-sized paper with "Ahhhhhh hhhhhhh" written in black sharpie. The frame is white and hangs on a light blue wall.
# Kapitel I. Matrizenrechnung ## § 1. Elementare Operationen. Funktionen Wir rechnen mit quadratischen unendlichen Matrizen¹, die wir hier mit fetten Buchstaben bezeichnen wollen, während schwache Buchstaben stets gewöhnliche Zahlen bedeuten sollen: \[ a = (a(n, m)) = \begin{pmatrix} a(0,0) & a(0,1) & a(0,2) & \cdots \\ a(1,0) & a(1,1) & a(1,2) & \cdots \\ a(2,0) & a(2,1) & a(2,2) & \cdots \\ \vdots & \vdots & \vdots & \ddots \end{pmatrix} \] Gleichheit zweier Matrizen bedeutet Gleichheit entsprechender Komponenten: \[ a = b \quad \text{heißt} \quad a(n, m) = b(n, m). \quad (1) \] Addition wird definiert durch Addition entsprechender Komponenten: \[ a = b + c \quad \text{heißt} \quad a(n, m) = b(n, m) + c(n, m). \quad (2) \] Die Multiplikation wird definiert durch die aus der Determinantentheorie bekannte Regel „Zeilen mal Kolonnen“: \[ a = b \cdot c \quad \text{heißt} \quad a(n, m) = \sum_{k=0}^{\infty} b(n, k) \cdot c(k, m). \quad (3) \] Potenzen sind durch wiederholte Multiplikation zu definieren. Es gilt das **assoziative Gesetz** für die Multiplikation und das **distributive Gesetz** für die Verbindung von Addition und Multiplikation: \[ (a b) c = a (b c). \quad (4) \] \[ a (b + c) = a b + a c. \quad (5) \]
A bar chart titled “Babies named ‘Kilo’.” The horizontal axis shows years (1990–2023), and the vertical axis shows the rate of babies named Kilo (in “Kilo/hour”). The bars are blue. The bars show moderate usage of “Kilo” in the early 1990s, a gap in the late ‘90s and early 2000s, a small jump in 2004, then mild usage in 2010–2012. There is a surge in 2021 to 2023, reaching its highest rate in the final year shown, 2023.
Two pink boxes on a Target store shelf. The box says "OLIPOP" and advertises a strawberry vanilla flavor of canned soda. A "sale" sign hangs above.
A beige PCB inside a steel cabinet. A clamp is twisting the PCB slightly. This is the "SureLight" control board for a Lennox furnace.
Five cubical dice from the ISAC museum at UChicago on a beige fabric background; the five dice show a 6, 4, 4, 6, and 3 on the upper faces and are marked with dark circles. Despite being very old, the layout of the dots on the dice is modern. Picture by Jim Fowler, but more information from the collection is available at https://isac-idb.uchicago.edu/id/c261d526-5c77-4cd5-b6ee-7102864c2528
The Starbucks mermaid logo, but drawn as a circle packing evoking the hyperbolic plane
The top row consists of nine nickels; the bottom row consists of ten pennies. The two rows appear to be the same length.
a hexagonal lattice of dimes, with a red label labeled "nine inches" between the centers of the dime in the lower left and the dime in the upper right.
exp(pi * sqrt(163)) = 262537412640768743.9999999999... sqrt(163) * diameter of a dime = 9 inches.