Following this pair of tweets about water:
A bucket full of water contains more atoms than there are bucketfuls of water in the Atlantic Ocean
— The QI Elves (@qikipedia) February 5, 2012
.@qikipedia There are 10,000× more molecules per pint of water than pints of water on earth. (3×10^21 pints/earth vs 2×10^25 molecules/pint)
— Matt Parker (@standupmaths) February 5, 2012
The obvious question is, at what point are the two numbers the same? Or,
If you put all the Earth’s water into containers of the same size so that each container carries as many atoms of water as there are containers, how big is each container?
Click here to continue reading Putting all the world’s water in buckets on cp’s mathem-o-blog
January’s MathsJam was a bit massive. It’s now a week later and I’ve only just gathered enough thoughts together to do this writeup.
There were nine of us this month, all but one of whom either maths students or lecturers. A major theme of the night was of professional mathematicians or nearly-professional mathematicians forgetting basic high-school methods. This led to quite an intense session of puzzling and proving.
Things didn’t start out that way, though. A few weeks ago I found the website of a mathematician in Illinois called Alan Schoen, and his page about Lominoes. They’re a pretty interesting set of shapes!
Click here to continue reading Newcastle MathsJam January 2012 Recap on cp’s mathem-o-blog
Lots of people have blogs where they talk about maths. Lots of these people just use plain text for mathematical notation which, while it gets the point across, isn’t as easy to read or as visually appealing as it could be.
MathJax lets you write LaTeX and get beautifully typeset mathematical notation. And it’s really really easy to set up: you just need to paste some code into the header of your blog’s theme. To make it really really really easy, I’ve written some very detailed instructions of what to do for each big blogging service. (If you’re reading this after I wrote it, which you definitely are, beware that the interfaces I describe may have changed, so the advice below might be inaccurate.
Click here to continue reading How to get beautifully typeset maths on your blog on cp’s mathem-o-blog
I’m going to try collecting additions to my Interesting Esoterica collection in let’s-say-weekly posts. I’ll link to each item, maybe paste its abstract, and write a sentence or two about it. Let’s see if it catches on. I’m not sure if I’ll have the will to do this regularly. I’m in a bit of a getting-things-done mood today.
As this is the first one, and I’ve added loads of stuff in January, for this first post I’m using everything I’ve added since the New Year. Future posts shouldn’t be anywhere near as long.
I should explain what the Interesting Esoterica collection is about.
Click here to continue reading Interesting Esoterica Summation on cp’s mathem-o-blog
Recently, someone left my office at Newcastle University and a new person took their place, so we needed a new sign on our front door. I wanted to do something clever with it, but it needed to be instantly legible to lost supervisors trying to find their students.
My first thought was that since there are seven of us, something to do with the Fano plane would look good. Our names didn’t have enough of the right letters in the right places for it to work, though.
That got me thinking about the Levenshtein distance. The Levenshtein distance between two strings is a measure of how many changes you need to make to one to end up with the other.
Click here to continue reading The sign on my office door on cp’s mathem-o-blog
Amazingly, December’s MathsJam had a non-trivial attendance of six whole people. And not just any people! Puzzling heavyweight David Cushing had yet more Renaissance-era riddles to test us all, and the other regulars were in similarly bamboozling form.
I balanced things out by failing to prepare anything or bringing anything to take notes on and subsequently forgetting most of what the others talked about. So this isn’t going to be a very accurate record of what happened, unless I get some reminders in the comments.
I’m going to start with a rather lengthy deconstruction of a puzzle Matthew Taylor posed:
A “lights out” puzzle
Matthew posted this puzzle on twitter a couple of days before the MathsJam night.
Click here to continue reading Newcastle MathsJam December 2011 Recap on cp’s mathem-o-blog