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David Roberts
Works at NCVER
Lives in Adelaide, Australia
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David Roberts

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We should have some of these for maths journals:

http://ineed.coffee/tag/journal-review/

Sadly, my experiences with the platform that Springer (one of the major mathematics publishers) uses have never been pleasant.
Given the general appreciation forx my small series of author-based reviews of academic journals, I will now report my experience with PeerJ Computer Science. PeerJ Computer Science is the second journal launched by the academic publisher of the PeerJ journal, which is called PeerJ, ...
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David Roberts

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Lawvere's Hegelian taco

Compare to the 'Monads are like burritos' meme [1].

Source: F.W. Lawvere, Display of graphics and their applications, as exemplified by 2-categories and the Hegelian “taco”, Proceedings of the first international Conference on algebraic methodology and software technology University of Iowa, May 22-24 1989, Iowa City pp. 51-74

[1] https://byorgey.wordpress.com/2009/01/12/abstraction-intuition-and-the-monad-tutorial-fallacy/
[2] http://chrisdone.com/posts/monads-are-burritos
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+Drew Armstrong thanks, fixed.
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From https://www.facebook.com/pratchett/posts/10152970826355025

Five things you need to know about The Shepherd’s Crown
1. It introduces a brand new character – young Geoffrey Swivel.
2. There is a devilish smart goat named Mephistopheles, who can count to twenty and use the privy.
3. Granny, Nanny, Magrat, Agnes, Petulia, Mrs Earwig, Long Tall Short Fat Sally and Miss Tick are all there. Along with a whole host of other much-loved characters.
4. It will make you see the humble Garden Shed in a whole new light.
5. An elderly gentleman’s toenails can be used as a powerful Feegle weapon.

Out this week!
Five things you need to know about The Shepherd’s Crown 1. It introduces a brand new character – young Geoffrey Swivel. 2. There is a devilish smart...
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I'm still hoping Weatherwax will die in this book. Would be a fitting end, I think.
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This is a lot of fun

http://arxiv.org/abs/1508.05908

Title: Heisenberg-picture quantum field theory
Author: +Theo Johnson-Freyd

Abstract: This paper discusses what we should mean by "Heisenberg-picture quantum field theory." Atiyah--Segal-type axioms do a good job of capturing the "Schr\"odinger picture": these axioms define a "d-dimensional quantum field theory" to be a symmetric monoidal functor from an (∞,d)-category of "spacetimes" to an (∞,d)-category which at the second-from-top level consists of vector spaces, so at the top level consists of numbers. This paper argues that the appropriate parallel notion "Heisenberg picture" should also be defined in terms of symmetric monoidal functors from the category of spacetimes, but the target should be an (∞,d)-category that in top dimension consists of pointed vector spaces instead of numbers; the second-from-top level can be taken to consist of associative algebras or of pointed categories. The paper ends by outlining two sources of such Heisenberg-picture field theories: factorization algebras and skein theory.

#arXiv arXiv:1508.05908
Abstract: This paper discusses what we should mean by "Heisenberg-picture quantum field theory." Atiyah--Segal-type axioms do a good job of capturing the "Schr\"odinger picture": these axioms define a "$d$-dimensional quantum field theory" to be a symmetric monoidal functor from an $(\infty ...
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David Roberts

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The title should be something more like "Is it true that girls aren't good at math?", with the obvious answer.

#womeninstem
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+Havvanur Dervişoğlu If you read the article you will see it does not agree with the title either.
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CML building with the Black Stump in the background.

#Adelaide
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David Roberts

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[...]THE FIRST thing that people invariably notice about Felicia Maria “Shasha” Magpantay is that she looks like she barely got out of high school. But this young-looking 28 year old has already racked up an impressive curriculum vitae in the academic field. Consider this: a Ph.D. in Applied Mathematics from McGill University in Montreal, Canada,  [...] And just this August, Shasha became the first Filipino woman to join the Department of Mathematics as a tenure-track professor at the research-intensive University of Manitoba. Not bad for a little girl who had initially considered a career as a ballerina.
THE FIRST thing that people invariably notice about Felicia Maria “Shasha” Magpantay is that she looks like she barely got out of high school. But this young-looking 28 year old has already racked
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Thanks, +Bruce Elliott , I suspected something like that.
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This is sad, but Unibooks is only one-third the size it was when I started at Adelaide: they moved from a multi-storey format into a single floor a few years back. Their physics and mathematics sections took a huge hit in the downsize.

http://www.abc.net.au/news/2015-08-26/unibooks-closure-to-hit-more-than-100-jobs/6727648

#adelaide  
More than 100 jobs will go with the closure of Unibooks, the Adelaide supplier of study materials for SA's three public universities.
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+Kevin Clift : I love Foyles! More or less every time I am in London I go there :-)
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Yes. 
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A review of a very interesting book that shows that a) quantum mechanics and b) much (if not all) of general relativity can be formalised in a strict finitist foundation. Not to mention all mathematics derived in the constructive system BISH (edit: according to the reviewer. See comments below).

http://journals.uvic.ca/index.php/pir/article/view/13181/4184
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+Bas Spitters​ hmm, that seems likely. The reviewer does mention Ye spends time developing things not relying on that claim, so while BISH isn't interpretable, the rest of the results hold up. I'll see what I can do regarding the nLab, but I can't really add much.
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Just checked the local 1-forms I defined give a connection on a nonabelian gerbe: the lifting gerbe for a G-bundle and a normal extension of Lie groups K --> G^ --> G. The middle equation in the picture is the analogue of what is known as the equation for a "bundle gerbe connection" in the abelian world.

Feeling quite pleased with this, as this was the last, most complicated, equation to verify.

#geometry #mathematics 
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And I believe I can write down an explicit solution to this, now, together with the other two families of local forms: A^, as above, and B (not seen in the picture), satisfying two more linked nonlinear differential equations.
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Have him in circles
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  • NCVER
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  • University of Adelaide
    2012 - 2015
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Mathematician, among other things.
Introduction
I live in Adelaide, Australia.

I am a pure mathematician who works on category theory and a smattering of related fields such foundations and higher geometry.

I works as a data analyst, of sorts, at the National Centre for Vocational Education Research (all views expressed here are my own).

I am a visiting fellow in the School of Mathematical Sciences at the University of Adelaide.

My nLab page: http://ncatlab.org/nlab/show/David+Roberts
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