Carnival Of Mathematics 206 – July 2022

Welcome to the 206th Carnival and my third time hosting the event.

To see past entries in the Carnival Of Mathematics and future scheduled hosts, please visit The Aperiodical.

I am honored to again host the Carnival of Mathematics! I learn so much from hosting; things I usually wouldn’t be exposed to are jam packed into every Carnival Of Mathematics post. Be sure to dig into the archive!.

Here are the entries. Enjoy!

Math Vs Culture

by Storm Bear Williams

A short little rant about all of those forgotten mathematicians from antiquity that hardly ever get the credit they deserve.


Mom Does Math

by Dr. Alyssa J Foss

I’m on the life long journey to recover from math-phobia. Which is why I have thrown myself into the math world head first! Next to momming and mathing, writing is my favorite thing. So, I’m trying to do the blog thing. This is my first post from September.

LINK

Editor’s Note: Her blog, Math Rehab, is really well written. Very worth the read!


What Is the Pascal Matrix?

By Nick Highham

In mathematics, particularly matrix theory and combinatorics, a Pascal matrix is a (possibly infinite) matrix containing the binomial coefficients as its elements. It is thus an encoding of Pascal’s triangle in matrix form. There are three natural ways to achieve this: as a lower-triangular matrix, an upper-triangular matrix, or a symmetric matrix.

Here Professor Higham steps his way through an example.

This article is part of the “What Is” series, available from https://nhigham.com/index-of-what-is-articles/ and in PDF form from the GitHub repository https://github.com/higham/what-is.

LINK

Editor’s Note: For more on Professor Highham; Twitter, Wiki, Google Scholar, Blog.


Ivan Guo: Financial models of the future

by Dr Ivan Guo

How can a 240-year-old logistics problem be used in quantitative finance? Dr Ivan Guo’s research lies predominantly in the areas of stochastic control and financial mathematics. In this interview with the Sydney Mathematical Research Institute, Ivan describes how stochastic transport theory applies in financial maths and how financial models are applied. He also debunks some misunderstandings about his field.


What does craiyon/DALL·E mini ‘think’ mathematics and mathematicians look like?

By Peter Rowlett

“You may have seen DALL·E mini posts appearing on social media for a little while now – it’s been viral for a couple of weeks, according to Know Your Meme. It’s an artificial intelligence model for producing images, operating as an open-source project mimicking the DALL·E system from company OpenAI but trained on a smaller dataset.”

Peter Rowlett presents a good introduction to DALL-E and offers several awesome examples.

LINK


Two Saturday Morning Breakfast Cereal Cartoons

by Zach Weinersmith

The first fun cartoon is titled “Incomplete”. LINK

The second is titled “Mathematics” and we can all feel this one down in our bones! LINK

Editor’s Note: You can find out more about the author here: Twitter, Facebook, Tumblr, Patreon


G0lomb

by Sneak Thief

One of my (many) interest areas is in algorithmic music composition. But it was not until @CarnivalOfMath mentioned that content didn’t need to be blogs, that I thought to submit this.

This piece is one where I use the Golomb ruler to determine the bar position, and length, of notes in a composition. I wrote a short piece of JavaScript which creates the data, incorporate it with a MIDI library which exports a MIDI file, that in turn can be loaded into a sequencer. I then assign each note to specific sound, based on their duration and what my ear tells me is good. (Being a synth-based composer, some sounds change a lot over time and are therefore better for long notes.)

The notes are always determined by me, a human, to match a particular key signature (to they sound in tune) and varied according to previous trial runs of the algorithm. So, for example, if notes of length 10 and 11 do not appear simultaneously I can assign them the notes E and F which (normally) do not sound good together. Similarly, I try to ensure that the start and end of the composition include notes which give an element of “resolution” which is prevalent in most western music. (Just because it’s based on maths, doesn’t mean it has to _sound_ that way!)

Finally, I sprinkle additional sounds generated by a different algorithm.

Click the image within the link to see a representation of the music, and 
you’ll clearly see the ruler being used.

LINK

Carnival Of Mathematics 195 – July 2021

Welcome to the 195th Carnival and my second time hosting the event.

To see past entries in the Carnival Of Mathematics and future scheduled hosts, please visit The Aperiodical.

I am honored to again host the Carnival of Mathematics! I learn so much from hosting, things I usually wouldn’t be exposed to are jam packed into every Carnival Of Mathematics post. Be sure to dig in to the archive!.

Here are the entries. Enjoy!

Bad Math Memes

By Storm Bear Williams

This is a video by me discussing how crazy I get when I see crazy math memes on Facebook and Twitter. Most are not educational and further separate mathematics from would-be students. We as mathematicians must do everything we can do to get people to EMBRACE mathematics, not shy away from it.


Here’s a proof that Tolkien’s Middle-Earth is not flat

By: @fermatslibrary (Twitter)

LINK


A 2021 problem: 20∼21 and 43×47

By: Ed Pegg
Submitted By: Lewis Baxter

Ed Pegg noticed that 2021 = 43 x 47 which are successive primes with 20 and  21 being successive integers. He asked for similar solutions and Robert Israel quickly found the next biggest solution, a number with 36 digits. I (Lewis Baxter) found more than 1500 bigger solutions, the largest having  3011 digits. This month I certified the two primes (which are  20690  apart). Unlike other “titanic” primes they are not the value of some small arithmetic expression.

LINK


Who Needs Trig Sub?

By: Patrick Honner

Mr. Honner sent this link in, bragging about what his students came up with. “This was the coolest math my students produce this year,” Mr Honner gushed!

“I’ve taught this topic for many years and never thought of this approach. I’m grateful to have learned something new from my students, who never fail to impress me with their creativity. And I’m glad I gave them time and space to solve what I thought was an impossible problem! When I teach this next time, I’ll be sure to do it again. And I’ll be sure to share this ingenious integration.”

LINK


When cubic polynomials have three real roots!

By: Freya Holmér (via Twitter)

Holmer Breaks down how they can be solved using trigonometry. Geometrically, you can visualize it as an equilateral triangle centered directly above the inflection point, where its vertices coincide with the three roots.


Why do perpendicular lines have slopes that are opposite reciprocals?

By: Howie Hua (via TikTok)

@howie_hua

Why do perpendicular lines have slopes that are opposite reciprocals? #math #mathematics #teacher #teachersoftiktok

♬ original sound – Howie Hua

Half a year of the Liquid Tensor Experiment: Amazing developments

By: Peter Scholze
Submitted By: Robin Whitty

“Exactly half a year ago I wrote the Liquid Tensor Experiment blog post, challenging the formalization of a difficult foundational theorem from my Analytic Geometry lecture notes on joint work with Dustin Clausen. While this challenge has not been completed yet, I am excited to announce that the Experiment has verified the entire part of the argument that I was unsure about. I find it absolutely insane that interactive proof assistants are now at the level that within a very reasonable time span they can formally verify difficult original research. Congratulations to everyone involved in the formalization!!

In this Q&A-style blog post, I want to reflect on my experience watching this experiment.”

LINK


Singmaster’s conjecture in the interior of Pascal’s triangle

By: Terence Tao
Submitted By: Robin Whitty

Kaisa MatomäkiMaksym RadziwillXuancheng ShaoJoni Teräväinen, and myself have just uploaded to the arXiv our preprint “Singmaster’s conjecture in the interior of Pascal’s triangle“. This paper leverages the theory of exponential sums over primes to make progress on a well known conjecture of Singmaster which asserts that any natural number larger than 1 appears at most a bounded number of times in Pascal’s triangle.

LINK


#GeometrySketchbook

Submitted By: Sam Hartburn

#GeometrySketchbook is a hashtag that has been used for a daily maths art 
challenge throughout June. A huge variety of media and art styles have been 
used; if you’re interested in mathematical art you’re sure to find 
something inspiring here.

LINK


Is This Some Kind of Code? You Can Solve the …

By: New York Times

(Paywalled)

SRC: New York Times

“Erik and Martin Demaine, a father-and-son team of “algorithmic typographers,” have confected an entire suite of mathematically inspired typefaces.”

The verb “puzzle” — to perplex or confuse, bewilder or bemuse — is of unknown origin. “That kind of fits,” said Martin Demaine, an artist in residence at the Massachusetts Institute of Technology. “It’s a puzzle where the word ‘puzzle’ comes from.”

LINK

Carnival Of Math February 2020

A Collection Of Math and Science Blog Posts From Around The World

Final Look at 2019: School, Science and Education
by Frederick Koh
A detailed review of 2019 examining science, school and education related events.

Hypot – A story of a ‘simple’ function
by Mike Croucher
Even the most simple looking mathematical functions can be difficult to implement on computers perfectly.  In this post, I look at an extremely common computation where the mathematics can be understood by children and yet efficient and bug-free implementation is complex and the subject of modern research.

Convergence rate of random walks
by John Cook
In some cases, random walks rapidly become more uniformly distributed, quickly going from obviously not uniform to apparently uniform.

Attracted to Attractors
by Ari Rubinsztejn
In this post 3 different chaotic attractions are visualized.

More Modular Knitting
by Pat Ashforth
Geometry in knitting (even for those who ‘can’t do maths’). How many different shapes can be knitted using only 45, 90 and 135 degree angles?

The Multiples of Me
by Sam Hartburn
The Multiples of Me is a poem about prime numbers, and why they needn’t be sad about having no factors.

Two dimensional tessellations at the Curious Minds Club
by Debbie Pledge
I run a recreational maths after school club in England. The post shows I got the children to explore the regular and semi-regular tessellations.

Australian Mathematicians
by LThMath
At the start of January we wanted to do something on our Facebook page to raise awareness about all the problems Australia has been through in the last period. We were shocked at the situation there.  For 2 weeks we researched and wrote more about Australian mathematicians and their work. In addition, each post has a link where you can donate for different charities and organizations. In this post we want to put together all the information we have discovered in those 2 weeks, including the mathematicians and where you can still donate to help.

Welcome to a Carnival of Mathematics!

This month, I will be hosting the Carnival Of Mathematics blog.

The Carnival of Mathematics is a monthly blogging round up hosted by a different blog each month. The Aperiodical will be taking responsibility for organizing a host each month, and links to the monthly posts will be added here. To volunteer to host a forthcoming Carnival (see below for months needing a host), please contact them on their website.

The Carnival of Mathematics accepts any mathematics-related blog posts, YouTube videos or other online content posted during the month: explanations of serious mathematics, puzzles, writing about mathematics education, mathematical anecdotes, refutations of bad mathematics, applications, reviews, etc. Sufficiently mathematized portions of other disciplines are also acceptable.

A FAQ can be found HERE.

I have the honor of hosting the anniversary Carnival! The Carnival of Mathematics will be 13 years old on February 9th.

If you want to get your math related post submitted, fill out this Google Form for consideration.

Brace yourself, there will be a test later.