There are categories of ‘spaces' that are not categories of locales

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Video in TIB AV-Portal: There are categories of ‘spaces' that are not categories of locales

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There are categories of ‘spaces' that are not categories of locales
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We described a short list of categorical axioms that make a category behave like the category of locales. In summary the axioms assert that the category has an object that behaves like the Sierpnski space and this object is double exponentiable. A number of the usual results of locale theory can be derived using the axioms: the (weakly) closed subgroup theorem proved, closed and proper surjection are of eective descent, parallel theories of discrete and compact Hausdor spaces emerge. An example is given of a category that satises the axioms but which is not the category of locales for any topos. We show how to embed the category of elementary toposes into the category whose objects are categories that satisfy the axioms.
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Point (geometry) Standard error Exponential smoothing Group action Transformation (genetics) State of matter Correspondence (mathematics) Multiplication sign Equaliser (mathematics) 1 (number) Morphismus Many-sorted logic Lecture/Conference Term (mathematics) Modulform Algebra Alpha (investment) Condition number Area Potenz <Mathematik> Moment (mathematics) Expression Category of being Proof theory Quotient Right angle Homomorphismus Object (grammar) Thomas Bayes
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Point (geometry) Exponential smoothing Group action Finitismus Logarithm Multiplication sign Proper map Junction (traffic) Theory Power (physics) Product (business) Many-sorted logic Lattice (group) Modulform Series (mathematics) Stability theory Condition number Principal bundle Topologische Gruppe Potenz <Mathematik> Constraint (mathematics) Prisoner's dilemma Computability Commutator Complete metric space Local Group Numerical analysis Equivalence relation Connected space Category of being Elementary arithmetic Computer animation Doubling the cube Logic Network topology Topostheorie Object (grammar) Resultant Local ring Spacetime Gradient descent
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completely different categories of spaces that and also categories the categories of spaces that on all the categories of low-cost this time we're kind of attack is what is going to recall some of the properties of the category of locales notably that there is a government double exponential object in that category living look at bats double exponential object in in any category and prove stability results for that double exponential object and and that will actually give me up costs of categories that has a stove likes manageability 2 minutes and then the sort of point of the talk is to show that that costs 1 of an example of a can that form with the double exponential military cannot be a category of locales and then if I got time Noppadol little bit of 70 roundabout in and so justify saying it actually a category that does have this double exponential ability is like a category of spaces so you can do a lot of topological space a local theory within within my cat within that terms that within a category that satisfies as axioms the answer when it'll be about lock category locales I'm gonna write this for BSA Penske locale set the skillet ,comma main property that we have reason for all this for all locals X set Penske the statements came to the X exists and the to X doesn't always exists because not everything is likely compact so what 1 mean by that what we do have appreciate Fountain said Pinsky to the X came from lock Paul the Senate to the the opposite the category locals set and that sends any y lot White white-owned context ,comma statements so you can define that and that is the exponential In the preachers category so when I say that this exists what I mean is that you need a recipient's to the power sit-ins GTX not once not preachy the exists In the preachy category local ,comma sets and it is represented when we have that we write the effects the double exponential it is a property of a captive locales this double exponential exists the key universal characterization the points of PX on winding the double exponential that they correspond to natural transformations more prisons in the appreciate category pacific and To the X statements to the y and once you have that you have the defines a strong it is also interesting tonight but once you think about this appreciate category you can do actually quite a bit of topology so for example you can prove that a local ,comma FSU next y it is open if an earlier there exists a left a joint recipients into the air so there's a natural transformations in in appreciate category such are the usual from being reciprocity condition holds and is also well known and that we can once we can say World open map is relative to any any category I guess with the final minutes of the final product and we can say what the discrete objects are said we say that excess In any contacts with the lot some objects at Penske axes discreet if and only if the finalized diagonals are there and all of this works all of this works relative to arbitary elementary top so you can have a discrete objects relative to lot well it's at any age let's just he again and beds in the cashiers locales relative to a venue elementary troubles set the fair and I want to prove police outlined the priests about double exponential currency it's essentially saying the public's legibility is closed under the formation of G objects the proposition so and if see just as to have finally products that's why any assumption so I hopefully if nobody's interests only the local theory little bat spaces they'll see this is an interesting result about the likes manageability so and we have an object a such that a and EX exist In see for all object facts we have G which is a good thing which is a group in the day's top products so we can't about internal growth then the results says that way the point 2 face points text ,comma exists for all g objects thanks ,comma adjust the clarity so I'm talking relatives now To this category pursues appreciate nation notation for it but it has as objects and they have to yield as objects so that a typical example is X and Due to inspect their steps
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wanted and so this embeds in that because of that equalizer and the following here the final step in the process is to observe this is what I meant by Fleet got this left to join in the together from there that said she magnetic possessor of their captive men as and minor enjoyed induced by that but is also satisfies for beanies reciprocity and because the service was Rabin is reciprocity this actually extends contravariant only to an injunction in the appreciate category um so that's ,comma blanket so unwinding that junction appreciate categories we see that these natural transformations actually can be related back to natural transformation from a to B X aides why because this is the this is the free G times what Jeffries on the left on left a joint is visit contravariant so that's downright joint misconduct and there's a little bit of checking to do that the condition here corresponds to equalizing with those 2 arrows says an additional check public recounted but that's how you should that if you have an object in an algae the note you guessed which just as finally products then double exponential ability is is G stable but Florida so knowledge to make the medium of promises little incentive of give you an example of a category that has this property but is not necessarily the cashmere locales so I'm going to prove some insight GE is saying opened let Kaliningrad and went through some of the consequences of an assumption then g of lock is equivalent the lock can give locales over some mn policy so is a managed troubles can develop positive red was going to happen if I do you make the captives that locals of the G accident action the same things that catch be calls professing to observe is that as a 70 so big opening remarks that we can embed the as the discrete objects relative to this category I can do exactly the same thing over here because I have a say Penske like object in here this just Penske with the federal action on it so I can define discreet and unopened and I can look at the discrete objects relative To this category and it's a dilemma but it's relatively easy to see by detaining power just described in terms of describing natural transformations relative 2 GTE's Back in terms of relative natural cultural and natural smell of natural transmissions relative to lock White unwinding the fair wages or proposition or just proved you can actually checked with the discrete objects relative to hear of the same thing as as BG so just the usual thing assets with the G action on it so the objects adjusted and just discrete locales so with that information playing we know that these 2 things as an equivalence and because equivalent that's not what we noticed troubles anyway but as a top also is the same as that topples therefore they don't have the same categories all locales but we also know from well my enjoyment Jenny result for any g there is actually a geometric morphism here which is an open suggestion on the sly synergy GE was opened in the beginning that's surjection and instead therefore of affected descent and is well known in the media statement effect being affected descent means that the calls over BG I've given by g objects relative to the group that you get by pulling back these 2 and look-alike geometric morphisms against each other that pulls back in then their captive also policy to be Angie hat which he had is the and Alamo dike as the Intel completion of due said this actually His isomorphic to the daily equivalent rather to medium g objects relative 2 The as Sergio Paez only it's how completion of G the walk up overwhelmed then missing a little bit of detail you could also show that these these at junctions are effectively as I ever lock 7
there's a technical aspect of that so using bad junction in the case lock you actually means equivalences commute with lock and then you can go OK with the Zirconia never lock they induce a ceremony on lock and therefore she is actually isomorphic did so it has to be a tall complete so since there are examples all groups the categories that are not itself complete there are examples of categories he is 1 of JI's not local complete but has this double exponential feature today and that was the main result but want to get across but I do I have a word with him had sought 3 minutes yet so to make it a bit more of railcars at a given time constraints have really been able to make that connection as precise as light as I'd like but OK that's very interesting but that doesn't mean a walls allowing you to collect thing Acosta's spaces they're on an ax medic approaches to locales you say I've got got in which category got finite products Monaco products cover-ups a pullback um stable above said Pinsky objects which is an internal distributive flattens it classifies open and close I've got a couple exponentiation um and got some other technical conditions around how this behaves interacting with equalizers and of reflecting on small office and things like that with those actions in play you have a category which you can prove that proper maps a pullback stable and this ejections are affected descent the year weekly close subgroup Fareham holds off from his Hoffman this loft Lofaro holds II could be topological lattice series is an awful lot of you can do which I would call local ferry but we've now shown you can do that local theory without actually being a M a catch so that's why I've them headlined it can't create spaces that are not categories of locals the top the list the amendment you question about the I'm of 1 of the nation's Communications in the sense that it will forget why you'd have to give me a bit more of a conflict a lot of questions the president of the pilot machinist of mission I think that after the Cup I've I mean just out of interest as it may be related to the double power there's anything like the express really comes from the low-power local at lower power and author constructions and those were originally developed into main theory in in the rest computer science so you I actually in inaction ,comma decide the constructions era she come from various computers USB unlawfully with continuations of and cut becoming 1 more hit commented unless another question at the the other thing this is of even more interesting about it is that you can the 3 stop said you can you got your below Kowalski that works reached top the you could also frees geometrical forms of you can have in the junction between locales and that Junction care commutes with the double Power construction wherever it wherever I rented out and that she characterizes geometric Wolfensohn's so you can actually in bed the Academy of top bosses in this category of spaces and it's it's fully faithful and I guess what this is saying is that it's and you know there's more of them than there are of geometrical prisons and a dozen preliminary work and some of the properties of geometric morphism seemed to work in this In this logic category but 1 of you have hailed as 1 of the last day of the eye that is I don't think yeah that's a good question and and you know you could take the view a where you got it wrong you know you have captured locals are Armuchee taking the opposite view I think it's it's it's a more exciting interesting thing because and and another thing if countries that 1 of the key results a topless theory is that when got only category .period the points of the locality group would correspond to the principal bundles relative to the it's how completion but in this case once better in his logic and large category you get the principal bundles without having to go to the itself completion so my intuition is that it's actually in some sense that there was a lot of health among yeah this is as far as I'm aware there is no idea is known elementary characterize Asian and um 58 speed Thomas struck I think he presents as a fact she called an elementary characterization of dozens slightly awkward known elementary catheterization side never mailed to tie it down and I have been a number of years I guess this this sort of coming along and last year were earlier policies may be thing action to step outside looks like I think the candidates it was the 1st few as