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<p class="MsoNormal"><span style="color:black">Hi all,<br>
<br>
On Monday, the MSP101 talk will be given by Jules Hedges (MSP, Cybercat Inst.). See the details of the talk below.<o:p></o:p></span></p>
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<span style="color:black"><br>
Best,<br>
Dilsat<br>
<br>
**********************************************************************<br>
<br>
Date: Monday, 03 February at 15:00<br>
<br>
Room: LT209, Livingstone Tower<br>
<br>
Zoom link: <a href="https://strath.zoom.us/j/85449272187?pwd=0qNkQqybiaKgBpbEBRv38x11x4db5n.1" target="_blank" title="https://strath.zoom.us/j/85449272187?pwd=0qNkQqybiaKgBpbEBRv38x11x4db5n.1"><span style="color:#96607D">https://strath.zoom.us/j/85449272187?pwd=0qNkQqybiaKgBpbEBRv38x11x4db5n.1</span></a><br>
<br>
Speaker: Jules Hedges<br>
<br>
Title: We solved dependent optics!<o:p></o:p></span></p>
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<span style="color:black"> <o:p></o:p></span></p>
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<span style="color:black">Abstract: There are two major generalisations of lenses. First there are optics, which require almost nothing of their base category and give you something in return. And then there are dependent lenses (aka container morphisms, aka
natural transformations of polynomials), which require a lot of their base category but give you even more in return. One day several years ago I innocently twote the question of how to unify these two constructions, which is motivated for mathematical, computational
and sociological reasons. The problem ended up occupying us (joint work with Dylan Braithwaite, Matteo Capucci, Bruno Gavranoviĉ, Eigil Rischel and André Videla) for several years, and its difficulty became a meme.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:black">I will explain the answer that finally satisfied us. This involves first constructing a category of "dependent adaptors" and then freely adjoining a particular family of monoidal costates using a technique we call
"weighted coparametrisation" that we reinvented. The definition began life as a prototype in Idris using QTT features, and was then translated back into category theory using what might or might not be a novel semantics of polymorphic dependent type theory.<o:p></o:p></span></p>
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**********************************************************************<o:p></o:p></span></p>
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