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Richard Elwes
Works at University of Leeds
Attended University of Oxford
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Richard Elwes

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Turkish academics persecuted for petition

Turkish academics who have openly criticized Turkey’s military crackdown on ethnic Kurdish communities are now feeling the wrath of their government. In recent days, the government arrested 33 academics. Although all have since been released, 15 have been fired from their university posts. The course of action started on 11 January, when a letter protesting violence in Turkey's ethnically Kurdish southeastern region, and calling on the government to make peace with Kurdish rebels, was posted online. Meanwhile, more than 2200 academics in Turkey and more than 2300 abroad signed it.
Read more at Science:
http://www.sciencemag.org/news/2016/01/turkish-academics-pay-price-speaking-out-kurds

The Guardian:
http://www.theguardian.com/world/2016/jan/15/turkey-rounds-up-academics-who-signed-petition-denouncing-attacks-on-kurds

A petition to the Turkish government can be found here:
http://barisicinakademisyenler.net/node/98.html
Turkish academics who have openly criticized Turkey's military crackdown on ethnic Kurdish communities are now feeling the wrath of their government. In recent days, the government arrested 33 academics. Although all have since been released, ScienceInsider has learned, 15 have been fired from ...
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An inefficient definition

The mathematician Nicolas Bourbaki (who was actually not a person but a collective) sought to build up the whole of mathematics from scratch (or more accurately, from a small number of underlying axioms). In a footnote on page 55 of Chapter 3, they define the number 1. The logician Adrian Matthias has unpacked that definition, and shown that when written out in full it "comprises 4,523,659,424,929 symbols together with 1,179,618,517,981 links between certain of those symbols".

https://www.dpmms.cam.ac.uk/~ardm/inefff.pdf
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+Yemon Choi, yes the paper which started all this was his The Ignorance of Bourbaki: https://www.dpmms.cam.ac.uk/~ardm/bourbaki.pdf
The paper linked to in my post and the one you mention are both follow-ups of that.
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The biggest known prime number just got bigger

The 49th known Mersenne prime, and largest prime so far discovered is 2^(74,207,281)–1.

Congratulations to Cooper, Woltman, Kurowski, Blosser & GIMPS!

http://www.mersenne.org/primes/?press=M74207281
GIMPS has discovered a new Mersenne prime number: 2^74207281-1 is prime! Discovered: 2016 Jan 07
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The idea of a number suddenly getting bigger fills me with dread.

But hurrah for finding a new one!
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"That the symbolic processes of algebra, invented as tools of numerical calculation, should be competent to express every act of thought, and to furnish the grammar and dictionary of an all-containing system of logic, would not have been believed until it was proved." (Augustus De Morgan, in A Budget of Paradoxes.)

Taken from George Boole and Boolean Algebra by Stanley Burris in the latest EMS Newsletter, page 27 here:
http://www.ems-ph.org/journals/newsletter/pdf/2015-12-98.pdf#page=29
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A New Year's Message from EMS President Pavel Exner

We look back at a memorable 2015, and forward to an exciting 2016.
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Rolling an oloid

There is something unusual that happens when you roll the shape called an "oloid" (but not when you roll e.g. a cylinder or cone): every part of the surface touches the ground at some point.

To make an oloid you start with two interlinking circles of the same size, set at 90 degrees to each other, and then fill in all the gaps. (The technical term for filling in the gaps is "taking the convex hull".)

https://www.youtube.com/watch?v=GM3_JuFgJ2E
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The baths and deaths of Archimedes

According to Plutarch, Archimedes's dedication to science was so intense that it "made him forget his food and neglect his person, to that degree that when he was carried by absolute violence to bathe or have his body anointed, he used to trace geometrical figures in the ashes of the fire, and diagrams in the oil on his body, being in a state of entire preoccupation, and in the truest sense, divine possession with his love and delight in science."

It's said that Archimedes was eventually murdered by a Roman soldier, angered by his refusal to accompany him until he'd completed his calculation. Over the centuries, this tragic death has been depicted by several artists. Here's an archive, courtesy of New York University Maths dept: https://www.math.nyu.edu/~crorres/Archimedes/Death/DeathIllus.html
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What is the most beautiful equation?

The BBC is holding an important public consultation on the above topic.

Click through, read about the candidates, and vote for your favourite.

http://www.bbc.com/earth/story/20160120-you-decide-what-is-the-most-beautiful-equation-ever-written?ocid
We asked a group of mathematicians and physicists to tell us their favourite equations. Now you get to decide which is the best
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+John Baez I wholeheartedly concede that what I did of e^(πi/2)=i mistreated your intentions with little justification (...)

Now assuming our would-be mathematician is a 21st century netizen s/he'd likely first ask Wolfram Alpha for this type of things and obtain loads of information about (the analytical continuation of) a "ProductLog" special function W_n(z) such that –W_n(–1), n a relative integer, are the fixed points of e^z -- and a related expression for fixed points of e^(πz/2), eg (–2/π)W_n(–π/2), with numerical approximations readily obtained:


–3   1.39951+8.90071 i
–2   1.02132+4.86835 i
–1    i
0    –i
1    1.02132–4.86835 i
2    1.39951–8.90071 i

...reading up on the applications of W_n that Wolfram Alpha provides, I discover that it can apply to computing electric potential lines of a plate capacitor, which reminds me with nostalgia of an undergrad physics lab experiment featuring analog simulation of capacitor geometries on graphite paper, whence I successfully spent a night to figure out a closed form for the field around an idealized grid, at the time of writing up the report (around '79, the birth year of uucp)... ...while battling a T.A. who'd declared the lab assignment absurd because he'd missed the point of the analog simulation (so that the presence of current clashed for him with studying an electrostatic situation).
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2016 Craaford Prize
 
The Royal Swedish Academy of Sciences has decided to award the 2016 Crafoord Prize in Mathematics to Yakov Eliashberg, Stanford University, Stanford, California, USA, “for the development of contact and symplectic topology and groundbreaking discoveries of rigidity and flexibility phenomena”.

Yakov Eliashberg was born 1946 in St Petersburg, Russia, he obtained a Ph.D. at Leningrad State University 1972. He is the Herald L. and Caroline L. Ritch Professor of mathematics at Stanford University, CA, USA.
 
http://fpme.link/I5juXT
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The Fermat Prize, 2015
 The laureates are:

Laure Saint-Raymond (École Normale Supérieure, Paris), for the
development of asymptotic theories of partial differential equations,
including the fluid limits of rarefied flows, multiscale analysis in
plasma physics equations and ocean modeling, and the derivation of the
Boltzmann equation from interacting particle systems.

Peter Scholze (Universität Bonn), for his invention of perfectoid spaces
and their application to fundamental problems in algebraic geometry and
in the theory of automorphic forms.

The prize-awarding ceremony will take place Tuesday the 22nd of March
2016 in Toulouse. More information on its schedule will soon be
available on the website:
https://www.math.univ-toulouse.fr/spip.php?article648&lang=en

The award amounts to a total of 20.000€ granted every two years by the
Conseil Régional Midi-Pyrénées. The recipient(s) is (are) required to
publish in the mathematical journal Annales de la Faculté des Sciences
de Toulouse an article summarizing their findings and aiming to explain
the significance of the results of the research rewarded by the Prize
to professional mathematicians not necessarily experts in the subject.

The EMS, as well as the French Académie des Sciences, the Société
Mathématique de France and the Société de Mathématiques Appliquées et
Industrielles, contributes to the composition of the committee of the
Prix Fermat, by appointing one of its member.
The laureates are : Laure Saint-Raymond, for the development of asymptotic theories of partial differential equations, including the fluid limits of rarefied flows, multiscale analysis in plasma physics equations and ocean modeling, and the derivation of the Boltzmann equation from interacting ...
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Natural ice art on the window this morning. Happy new year everybody!
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Did you leave some cookies for Jack Frost or something?
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Barry Cooper Obituary, now in print

My[1] obituary of Barry Cooper is printed in today's Guardian.

This is only of relevance to people who (a) are in UK and (b) prefer paper to screens. For everyone else, as previously advertised, it's online here:
http://www.theguardian.com/education/2015/nov/17/barry-cooper-obituary

[1] I want to acknowledge the help and input of Stan Wainer and Dugald Macpherson.
Other lives: Mathematician dedicated to promoting the work of Alan Turing
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Have him in circles
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Work
Occupation
Teaches & writes about mathematics
Employment
  • University of Leeds
    Mathematician, present
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Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Previously
Leeds - Oxford - London - Freiburg
Story
Tagline
A UK based maths lecturer & writer.
Introduction
Lives in Yorkshire, writes about Maths.
Bragging rights
Author of Maths 1001 & How to Build a Brain (AKA Mathematics Without The Boring Bits) & some other stuff, mostly on the subject of maths
Education
  • University of Oxford
    Mathematics, 1997 - 2001
  • University of Leeds
    Mathematical logic, 2001 - 2005
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Male