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David Roberts
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### David Roberts

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This makes me slightly unhappy: Elsevier chairman claims their core business is content creation. If they create their own content they don't need (and won't have) mine.

#thecostofknowledge

It has been a heady few years, but Chi says the innovation that has emerged in the aftermath of open source is invigorating.

“We will never abandon our core of quality content creation,” he says.

“But we have another hand (to play). We can create our own content, we can take everyone’s content and reuse it. That is the future for us. That is why we have been taking so much risk for the past seven years.”﻿
ALL good things come to an end. For academic publishers, that happened about seven years ago when a nascent open-source movement — born from the outrage of academics who wrote articles for free, peer-reviewed others for free and then were charged an arm and a leg to buy back their own work from rapacious publishing houses — started getting traction.
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guy yak

doesnt create scientific discoveries but sells things ¦

it is a provider not a scientist ¦ just look at its paywall of products as proof ¦

and scientists will discover that they do need that corporation to sell their discoveries ¦

academia is not among the hipsters of the revolution in publishing ||﻿

### David Roberts

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EDIT: Apologies, I didn't check this was actually watchable! (It's currently set to 'private') However, the other videos on the  from the event seem to be ok.
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Just watched it myself. Very interesting indeed!﻿

### David Roberts

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Some very nice lecture notes by !

http://arxiv.org/abs/1404.4918

Title: Six lectures on quadratic reciprocity
Author: Chandan Singh Dalawat

Abstract: Rousseau's simple proof of the quadratic reciprocity law, followed by the proof of its equivalence with Hilbert's product formula.

#arXiv  ﻿
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### David Roberts

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Masterful!

John Tate's contribution to the 1954 Amsterdam Congress.  He provides a one-page summary of 150 years of work on reciprocity laws (the central part of number theory).

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### David Roberts

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My 2006 MacBook battery died. :-( I meant to buy a spare at some point, but...﻿
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Try ebay﻿

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### David Roberts

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Very interesting!

http://www.tac.mta.ca/tac/volumes/29/6/29-06abs.html

Analytic spectrum of rig categories

Frederic Paugam

We define the analytic spectrum of a rig category $(A,\oplus,\otimes)$, and equip it with a sheaf of categories of rational functions. If the category is additive, we define a sheaf of categories of analytic functions. We relate this construction to Berkovich's analytic spaces, to Durov's generalized schemes and to Haran's F-schemes. We use these relations to define analytic versions of Arakelov compactifications of affine arithmetic varieties.

Keywords: Rig categories, global analytic geometry, generalized rings, Arakelov compactifications

2010 MSC: 18D10, 14G22, 14G25, 11G35, 18C15

Theory and Applications of Categories, Vol. 29, 2014, No. 6, pp 188-197.

Published 2014-04-21.﻿
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http://arxiv.org/abs/1404.4973

Title: Hat Puzzles
Author: Tanya Khovanova

Abstract: This paper serves as the announcement of my program---a joke version of the Langlands Program. In connection with this program, I discuss an old hat puzzle, introduce a new hat puzzle, and offer a puzzle for the reader.

#arXiv  ﻿
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Title: Extensions of flat functors and theories of presheaf type
Author: Olivia Caramello

Abstract: We develop a general theory of extensions of flat functors along geometric morphisms of toposes, and apply it to the study of the class of theories whose classifying topos is equivalent to a presheaf topos. As a result, we obtain a characterization theorem providing necessary and sufficient semantic conditions for a theory to be of presheaf type. This theorem subsumes all the previous partial results obtained on the subject and has several corollaries which can be used in practice for testing whether a given theory is of presheaf type as well as for generating new examples of theories belonging to this class. Along the way, we establish a number of other results of independent interest, including developments about colimits in the context of indexed categories, expansions of geometric theories and methods for constructing theories classified by a given presheaf topos.

http://arxiv.org/abs/1404.4610

#arXiv﻿
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### David Roberts

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