## SUMS

**27 May 2016**

Sydney University Mathematics Society -, said as SUMS, spelt ΣUMS, because the upper case Greek letter '"Σ'" is the symbol for '"sum'" in mathematics , calls itself a club for students with an interest in any and all things maths-related. Doesn't mathematics underlie everything? And I mean everything! So I had to ask, "What does ΣUMS do then exactly?"

Society president and, mathematics Ph.D. student, Sean Gardiner, told me about their popular weekly Thursday lunchtime talks and the interesting . What range of topics these cover. '"Australia Won the Ashes, Statistically'" was a recent one. In cricket there is always some interesting interplay between the game's summary statistics like number of runs, the average, and the strike rate. The presenter, Kevin Wang, showed a number of ways one could justifiably work the statistics to reveal Australia as the 2015 Ashes winner! Funny and c. Clever!

Another recent talk was '"Rubik's Cube Workshop and& Speed Competition', w"hich included a. A bit of talk on the mathematics underlying the puzzle, t. Then you could be taught how to master the Rubik's Cube, or be in the group that knew how to solve it, but now wanted to learn tricks to do so at lightning speed.

Another talk was '"Diophantine Analysis and Transcendental Numbers'", s. So something for those wanting a little more of the mathematically intense, though Sean says the speakers are always requested toaim to make sure no- one is left out.

ΣUMS has also joined up with the Linguistics Society and the Crossword Society to run '"Letters and Numbers'" evenings. ΣUMS executive member, Maggie Corrigan, organises these. Maggie is a Ph.D. student in chemistry who double majored in mathematics and chemistry for her undergraduate degree. She now brings all her mathematics to her equally loved chemistry, you see, e. Even recently giving a ΣUMS talk on some of the mathematics she's used to model chemical reactions! The '"Letters and Numbers'" evenings are based on the SBS TV show of the same name, though with a slightly shifted format so for there to beare the same amount of nNumbers puzzles as lLetters ones. Who plays the role of Lily Serna, the girl who computes the numbers puzzles in her head on the TV show? "The Python computer script," Maggie laughs!

There's a funny story here. On one of the evenings the projector wasn't working and they had to make do with Cass, the president of the Crossword Society, writing answers on a board. The answers were being dictated by Sean who was on his computer running the solution generating programs off to the side. By theIn the room setup, it turned out he was hidden by a piece of stage, and the audience couldn't see him. Everyone in the audience was thinking Cass was doing it all really fast in her head! Up came the Numbers puzzle: how can you make the number 171 with any of the numbers 1, 3, 6, 8, 75, 100? The players all returned the obvious: 100 + 75 - 3 - 1. The Python script returned:

(100×(8+3)+1-75)/6

Everyone was looking at Cass like she was a freak!

Anyway, anyway, what great diversity ΣUMS manages to capture! There are also mathematics cake competitions [see photo] and mathematics relays. Even a ΣUMS Puzzle Hunt -, an online competition where teams compete to solve 20 puzzles over five5 intense days to win as many points as possible (for cash prizes!). You don't need to have any specialist knowledge about any particular subject, it's aimed at a general audience. So again something for everyone.

Sean gave me some of the infamous mathematics relay questions to try out, and while solving where having solved yet another question concerning chocolate, I realised the other big theme in all this -, and again a theme for everyone - is: Food! There's free pizza at the talks, and most of the prizes for the competition events indeed take the form of chocolate! Oh ΣUMS gets the diversity in mathematics and people just right!

## Learn more »

ΣUMS talks, 1pm-2pm Thursdays, are all for general audiences, but high -school level is ensured during School Holidays. ... See http://www.maths.usyd.edu.au/u/PS/SUMS.html