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David Roberts
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David Roberts

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Once a paper is accepted for publication, the author is assumed to have transferred the copyright to World Scientific.

Is this even legit?? This is on the submission instructions for a reasonably reputable, though not stellar, journal published by World Scientific. Elsewhere details the policy for manuscripts/preprints:

Authors can also post the accepted author manuscripts of their research papers freely available at the end of an embargo period of 12 months following official publication or later, by placing them on personal websites, subject or institutional repositories or as stipulated by the Funding Agency.

Alright, this is fairly standard. But! At http://www.worldscientific.com/page/authors/author-rights it's even worse: they demand that if a paper is submitted to a World Scientific journal, the publicly available preprint has to specify the journal and slap a © on it:

You may post the preprint anywhere at any time, provided it is accompanied by the following acknowledgement:

Preprint of an article submitted for consideration in [Journal] © [Year] [copyright World Scientific Publishing Company] [Journal URL]

This is ridiculous! It's not at all clear with such a copyright line what the © applies to; I guess they mean the journal, but who knows, given the "assumption" in my first quote that © is transferred...

#nopenaccess  

cc +Peter Suber +Ross Mounce +Mike Taylor 
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Further to my recent post [1] about mathematics enrichment programmes in Australia, this is the sort of thing I'd rather see emulated:

http://mathbabe.org/2016/02/12/guest-post-a-math-circle-thats-breaking-the-mold/

rather than the elitist model as discussed in [2], which is what first springs to mind when these sort of things are discussed.

[1] https://plus.google.com/+DavidRoberts/posts/U73dQdukkVo
[2] http://mathbabe.org/2016/02/09/how-do-we-make-math-enrichment-less-elitist/
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I think an online maths circle website to help seed groups worldwide would be good as well. See also freecodecamp.com, which is part of the ongoing push to get adults to code, and how they're encouraging their audience to set up local groups.
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Gravitational wave papers now on the arXiv!

Observation of Gravitational Waves from a Binary Black Hole Merger
http://arxiv.org/abs/1602.03837 (the actual paper, published in Phys. Rev. Lett.)

Tests of general relativity with GW150914
http://arxiv.org/abs/1602.03841

Swift follow-up of the Gravitational Wave source GW150914
http://arxiv.org/abs/1602.03868

Astrophysical Implications of the Binary Black-Hole Merger GW150914
http://arxiv.org/abs/1602.03846

The Rate of Binary Black Hole Mergers Inferred from Advanced LIGO Observations Surrounding GW150914
http://arxiv.org/abs/1602.03842

Properties of the binary black hole merger GW150914
http://arxiv.org/abs/1602.03840

GW150914: First results from the search for binary black hole coalescence with Advanced LIGO
http://arxiv.org/abs/1602.03839

GW150914: The Advanced LIGO Detectors in the Era of First Discoveries
http://arxiv.org/abs/1602.03838

Observing gravitational-wave transient GW150914 with minimal assumptions
http://arxiv.org/abs/1602.03843

Characterization of transient noise in Advanced LIGO relevant to gravitational wave signal GW150914
http://arxiv.org/abs/1602.03844

Calibration of the Advanced LIGO detectors for the discovery of the binary black-hole merger GW150914
http://arxiv.org/abs/1602.03845

GW150914: Implications for the stochastic gravitational wave background from binary black holes
http://arxiv.org/abs/1602.03847

Testing Gravity with Gravitational Wave Source Counts
http://arxiv.org/abs/1602.03883

Any that I missed?

#gravitationalWaves  
Abstract: On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of $1.0 ...
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Danke. Nun kann ich endlich auch einmal die Ergebnisse der Studie einsehen, an der ich teilgenommen habe.
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Pretty cool stuff...
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Observation of Gravitational Waves from a Binary Black Hole Merger (licensed CC-BY)

B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration)

Phys. Rev. Lett. *116*, 061102 – Published 11 February 2016


On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10^−21. It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203 000 years, equivalent to a significance greater than 5.1σ. [...snip...] These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

http://dx.doi.org/10.1103/PhysRevLett.116.061102

#openaccess   #gravitationalWaves  
Gravitational waves emitted by the merger of two black holes have been detected, setting the course for a new era of observational astrophysics.
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So cool and exciting
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Feb 11 is International Day of Women and Girls in Science!
Today is the inaugural International Day of Women and Girls in Science. In December 2015, the United Nations passed a resolution to recognise on February 11 each year women's contributions to the field. The UN's research showed females "continued to be excluded from participating fully in ...
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Claire VOISIN, elected to the College de France, will give the inaugural lecture of the chair "Algebraic Geometry" June 2, 2016 at 18pm.

#womeninstem  
 
Claire VOISIN, élue au Collège de France, donnera la leçon inaugurale de la chaire « Géométrie algébrique » le 2 juin 2016 à 18h.
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Claire Voisin Directrice de recherche, CNRS Institut de Mathématiques de Jussieu Equipe Topologie et géométrie algébriques 4, place Jussieu 75252 Paris Cedex 05. France claire.voisin@imj-prg.fr photo ****** Renaissance d'un journal: JEP (Journal de l'Ecole polytechnique) ********** ...
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It's an open secret that while HoTT has the clear potential to be relevant for practicing homotopy theorists and higher topos theorists, the field is not yet quite living up to it. There are a tiny number of people, first and foremost Mike Shulman, who really work on HoTT as a topic in higher topos theory. The progress especially Mike has been making is impressive, but to homotopy theorists who are not into type theory or foundations as such, the development of HoTT is still at most at the verge of being interesting.

Lurie's often quoted "no comment", as in this recent hott-cafe discussion:

 https://groups.google.com/d/msg/hott-cafe/oBRMrk17G0I/C9SBjrPaAQAJ

is just the most prominent example, I could give you a long list of names of top homotopy theory researchers who ought to be interested in HoTT-as-it-could-once-be but are dismissive about it at the moment.

I think this ought to change, and it may change. But changing this situation will require more man-years of work on the aspects of HoTT that are genuinely homotopy theoretic and higher topos theoretic.

Unfortunately, currently large parts of the field are actively pushing away from this direction, wich does not help to improve the situation.

For instance all the work on initiality of models of type theory is really something that belongs to traditional type theory and means nothing to practicing mathematicians. One sees vivd evidence this week where at MPI Bonn Vladimir is giving a "marathon", as he announced it, talk series on C-systems in the context of a program titled "Higher structures in geometry and physics": it leaves most people except a handful of accounting specialists utterly puzzled why they should care about this, and nobody gets away with the impresion that there is anything to be gained here for researchers in "higher homotopy structures".

Also the wealth of work on "cubical type theory" so far failed to really connect to homotopy theory as such. The problem that it is motivated by, to make univalence compute, is again something that research homotopy theorists could not care less about; it's pushing away from instead of towards the interest of homotopy theorists.

In contrast, I think it is clear that what needs to be done next in order to improve the impact of HoTT on research-level homotopy theory is:

First and foremost, fill that darn remaining issue with the weak Tarskian universes, such as to finally have as an official theorem (instead of as something that Mike Shulman finds too obvious to publish, while nobody else in the field understands) that HoTT has interpretation in every infinity-topos as in Lurie's book, not just in the (admittedly already impressive) two or three classes of infinite families of infinity-presheaf toposes (with strict universes) that Mike has, thankfully, constructed. Mike explained this here

 https://ncatlab.org/homotopytypetheory/show/model+of+type+theory+in+an+(infinity,1)-topos

and if I were in charge of HoTT, I would drop everything else until the statement on that webpage becomes an officially published article.

Second, really important would be to make progress on formalizing stable homotopy theory, i.e. "spectrum types" or at least something in this direction. Homotopy theory is so rich, that most computational progress in practice is made by "linearizing" problems, in the sense of Goodwillie calculus, hence by translating problems about homotopy types into problems about stable homotopy types (spectra) as far as possible.

For instance it's not too surprising that the HoTT community is currently stuck with computing but the most evident homotopy groups of spheres (another reason why any working homotopy theorist feels there is nothing to be found here): this was precisely the state of the field of homotopy theory, too, in the 50s, before stabilization and spectral sequences came along.

Again, it's Mike Shulman who has started to push this topic from a HoTT perspective

  https://ncatlab.org/homotopytypetheory/show/spectral+sequences

but it would be useful if more people in the field (anyone, for that matter) picked this up and developed this further.
 
Spectral sequences is the tool in modern research level homotopy theory (see the recent sensational proof of the Kervaire invariant one problem), it's where all the meat it. But also, it's computationally  demanding. Therefore, potentially, there is a fantastic chance here for any computer assisted homotopy theory, hence for HoTT. Once you had a piece of Coq that would read in a tower of homotopy types and which would then start crunching out the pages of its spectral sequence, you would be assured that all those homotopy theorists who previously had "no comment" to make on HoTT would start paying attention.

In short, I think currently HoTT as a topic in homotopy theory has an large ratio of potential over realization. Anybody who cares should think about investing more energy into research that actually goes in this direction. Go and contact Mike Shulman, if you are not sure which precise research questions to tackle. Read all his articles, to see what the state of the field of HoTT as a topic in homotopy theory is. Then work on this. I am optimistic that with effort spend in this direction, eventually homotopy theorists who had not been interested in type theory as such will take notice.
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See also +Michael Shulman​'s comments in the hott-cafe discussion.
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Another, weaker chirp showed up in the weeks that followed

This is what I want to hear about! What was that??

https://www.quantamagazine.org/20160211-gravitational-waves-discovered-at-long-last/

#gravitationalWaves  
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+Urs Schreiber I haven't looked at The Rate of Binary Black Hole Mergers Inferred from Advanced LIGO Observations Surrounding GW150914 (http://arxiv.org/abs/1602.03842), but I would guess it might be in there...
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All the main points you need to know.

#gravitationalWaves  
 
Graviational waves

The rumors are true: LIGO has seen gravitational waves! Based on the details of the signal detected, the LIGO team estimates that 1.3 billion years ago. two black holes spiralled into each other and collided. One was 29 times the mass of the Sun, the other 36 times. When they merged, 3 times the mass of the Sun was converted directly to energy and released as gravitational waves.

For a very short time, this event produced over 10 times more power than all the stars in the Universe!

We knew these things happened. We just weren't good enough at detecting gravitational waves to see them - until now.

I'll open comments on this breaking news item so we can all learn more. LIGO now has a page on this event, which is called GW150914 because it was seen on September 14th, 2015:

http://www.ligo.org/science/Publication-GW150914/index.php

You can see the gravitational waveforms here:

https://pbs.twimg.com/media/Ca8dpleUAAALI2n.jpg

At left in blue is the wave detected in Livingston, Louisiana. At right in red is the wave detected in Hanford Washington. The detector in Hanford saw the wave a few milliseconds later, so it must have come from the sky in the Southern hemisphere.

#LIGO #astronomy
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A treasure trove!
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If you want to see the original paper predicting #gravitationalWaves  , according to Nature News it's this:

A. Einstein, Näherungsweise Integration der Feldgleichungen der Gravitation, Sitzungsberichte der Preussischen Akademie der Wissenschaften zu Berlin, 1 (1916) 688–696,
http://echo.mpiwg-berlin.mpg.de/MPIWG:RA6W5W65

The title in English, as far as Google gets me, is Approximate integration of the field equations of gravitation. The key word to look out for is Gravitationswellen, 'gravitational waves'.
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Unfortunately I read that book about 7 years ago and my memory of it is hazy. If I remember I will check when I get home. 
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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 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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