Coherent duality: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
wikifying E. Matlis
en>Yobot
 
Line 1: Line 1:
In mathematics, especially in [[algebraic geometry]], '''base change''' refers to a number of similar theorems concerning the [[sheaf cohomology|cohomology]] of [[sheaf (mathematics)|sheaves]] on algebro-geometric objects such as [[Algebraic variety|varieties]] or [[scheme (mathematics)|schemes]].


The situation of a base change theorem typically is as follows: given two maps of, say, schemes, <math>f: Y \rightarrow X</math>, <math>g: X' \rightarrow X</math>, let <math>f'</math> and <math>g'</math> be the projections from the [[fiber product]] <math>Y' := Y \times_X X'</math> to <math>X'</math> and <math>Y</math>, respectively. Moreover, let a sheaf <math>\mathcal F</math> on X' be given. Then, there is a natural map (obtained by means of adjunction)
:<math>f^* R^i g_* \mathcal F \rightarrow R^i g'_* f'^* \mathcal F.</math>
Depending on the type of sheaf, and on the type of the morphisms ''g'' and ''f'', this map is an isomorphism (of sheaves on ''Y'') in some cases. Here <math>R^i g_* \mathcal F</math> denotes the [[higher direct image]] of <math>\mathcal F</math> under ''g''. As the [[stalk (mathematics)|stalk]] of this sheaf at a point on ''Y'' is closely related to the cohomology of the fiber of the point under ''g'', this statement is paraphrased by saying that "cohomology commutes with base extension".<ref>{{harvtxt | Hartshorne | 1977 | p=255 }}</ref>


{{Images of sheaves}}
We can now perform bingo online. Bingo is 1 of the most beloved gambling game and bing0  [http://www.purevolume.com/melodymabrydn/posts/6590698/Everything+I+Learned+About+Spilleautomater+Som+Det+Heter+P%C3%A5+Norsk+I+Learned+From+Potus norske automater] in Canada - or ought to I say all more than the globe is a trend  [https://www.rebelmouse.com/shermanwalls/how-to-gain-spillautomater-664220323.html automater villig nett] absolutely nothing can't take away. A bing0 site for all Canadian  [http://rochellebaldessin.newsvine.com/_news/2014/08/08/25223902-finding-the-best-spilleautomat Hvis du liker å spille på spilleautomater online] bingo  [http://www.purevolume.com/romeovalazquez/posts/6917325/Four+Things+Your+Mom+Should+Have+Taught+You+About+Slotmaskiner+Er+Blant+De+Mest+Popul%C3%A6re. spilleautomater som det heter på norsk] followers solely. If you are residing in Canada and loves to play Bingo, then welcome to my globe! And in these contemporary times bing0 had also been revolutionized. Furthermore, Bing0 websites devoted for certain nations experienced  [http://kellyeleyvazmcg.pen.io/ signifiant beste norske spilleautomater] been produced. Now how good can that be. Allow me tell you the reasons why you ought to play bing0 on-line today instead of going to Bing0 halls.<br><br>The last thing you  [http://www.kiwibox.com/samiraseibert/blog/entry/116862707/alle-spilleautomater-som-er-p-v-r-side-may-not-exist/?pPage=0 Spill sikkert hos website!] would want is to forget to perform and see your figures come up. Believe about how terrible that would be if you could have gained but did not get a ticket. One factor you can do that will help is maintain taking part in. If you truly want to know how you can start winning the lottery with extremely little effort then maintain studying.<br><br>As lengthy as there are two or much more scatter symbols anywhere on the slots machine reels then you can have a scatter win. A scatter image is represented by a Champagne symbol on Mega Fortune slots. This is because scatter symbols do not need to seem on the enabled line in [http://photo.net/gallery/tag-search/search?query_string=purchase purchase] to total a scatter win. Winning combinations of this symbol doesn't [http://Www.google.de/search?q=require require] to appear on your enabled line. The on-line slots  [https://www.rebelmouse.com/shermanyfgwlxqitt/7-signs-you-made-a-great-impac-666404335.html orgesspill] Paytable determine the payout of the successful mixtures. If a normal get and scatter get seem on the same round then each wins will be awarded.<br><br>Their company design is built to profit via your losses. And finally the 3rd lesson; be careful of Dealing Desk/Market Maker Currency Brokers. That is not a broker you want or should be carrying out company with, specifically when they companion with sketchy companies that do nothing at all but supply  [http://aldajuarezmtvsq.pen.io/ online spille automater] you with losing trades.<br><br>it has to be related else it will backfire. Make sure to use words that could easily curiosity the audience. You can find other web masters and make a deal with them to trade hyperlinks.<br><br>Do you truly want to listen to your ex's voice again? Here is how you can pull your  [http://www.purevolume.com/abbyaxvdulfl/posts/6931839/The+Ulitmate+Les+V%C3%A5re+Artikler+Og+Bli+En+Mester+P%C3%A5+Spilleautomater+Trick no cost norrman spilleautomater] ex back again once and for all. Does your ex not return your phone phone calls? Well you have strike the jackpot then! You are about to see three confirmed techniques that will get your ex to return your phone phone calls. Do you skip your ex like insane and want to get your ex back again?<br><br>Roulette is an individual of the most peaceful casino game which let you adequate time to socialize with the persons all over the gaming table. Keep in mind that sport is an amusement way, not a instrument to make money.
 
==Flat base change for quasi-coherent sheaves==
The base change holds for a [[quasi-coherent sheaf]] <math>\mathcal F</math> (on <math>X'</math>), provided that the map ''f'' is [[flat morphism|flat]] (together with a number of technical conditions: ''g'' needs to be a [[separated morphism|separated]] [[morphism of finite type]], the schemes involved need to be Noetherian).
 
==Proper base change for etale sheaves==
The base change holds for etale torsion sheaves, provided that ''g'' is [[proper morphism|proper]].<ref>{{harvtxt|Milne|1980|loc=section VI.2}}</ref>
 
==Smooth base change for etale sheaves==
The base change holds for etale torsion sheaves, whose torsion is prime to the residue characteristics of ''X'', provided ''f'' is [[smooth morphism|smooth]] and ''g'' is quasi-compact.<ref>{{harvtxt|Milne|1980|loc=section VI.4}}</ref>
 
==See also==
*[[Grothendieck's relative point of view]] in algebraic geometry
*[[Change of base (disambiguation)]]
*[[Base change lifting]] of automorphic forms
 
==Notes==
<references />
 
==References==
* {{Citation | last1=Hartshorne | first1=Robin | author1-link=Robin Hartshorne | title=[[Algebraic Geometry (book)|Algebraic Geometry]] | publisher=[[Springer-Verlag]] | location=Berlin, New York | isbn=978-0-387-90244-9 | oclc=13348052 | mr=0463157  | year=1977}}
* {{Citation | last1=Milne | first1=James S. | title=Étale cohomology | publisher=[[Princeton University Press]] | isbn=978-0-691-08238-7 | year=1980}}
 
[[Category:Sheaf theory]]

Latest revision as of 14:19, 5 May 2014


We can now perform bingo online. Bingo is 1 of the most beloved gambling game and bing0 norske automater in Canada - or ought to I say all more than the globe is a trend automater villig nett absolutely nothing can't take away. A bing0 site for all Canadian Hvis du liker å spille på spilleautomater online bingo spilleautomater som det heter på norsk followers solely. If you are residing in Canada and loves to play Bingo, then welcome to my globe! And in these contemporary times bing0 had also been revolutionized. Furthermore, Bing0 websites devoted for certain nations experienced signifiant beste norske spilleautomater been produced. Now how good can that be. Allow me tell you the reasons why you ought to play bing0 on-line today instead of going to Bing0 halls.

The last thing you Spill sikkert hos website! would want is to forget to perform and see your figures come up. Believe about how terrible that would be if you could have gained but did not get a ticket. One factor you can do that will help is maintain taking part in. If you truly want to know how you can start winning the lottery with extremely little effort then maintain studying.

As lengthy as there are two or much more scatter symbols anywhere on the slots machine reels then you can have a scatter win. A scatter image is represented by a Champagne symbol on Mega Fortune slots. This is because scatter symbols do not need to seem on the enabled line in purchase to total a scatter win. Winning combinations of this symbol doesn't require to appear on your enabled line. The on-line slots orgesspill Paytable determine the payout of the successful mixtures. If a normal get and scatter get seem on the same round then each wins will be awarded.

Their company design is built to profit via your losses. And finally the 3rd lesson; be careful of Dealing Desk/Market Maker Currency Brokers. That is not a broker you want or should be carrying out company with, specifically when they companion with sketchy companies that do nothing at all but supply online spille automater you with losing trades.

it has to be related else it will backfire. Make sure to use words that could easily curiosity the audience. You can find other web masters and make a deal with them to trade hyperlinks.

Do you truly want to listen to your ex's voice again? Here is how you can pull your no cost norrman spilleautomater ex back again once and for all. Does your ex not return your phone phone calls? Well you have strike the jackpot then! You are about to see three confirmed techniques that will get your ex to return your phone phone calls. Do you skip your ex like insane and want to get your ex back again?

Roulette is an individual of the most peaceful casino game which let you adequate time to socialize with the persons all over the gaming table. Keep in mind that sport is an amusement way, not a instrument to make money.