Order Topology on a Preorder












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While looking at the definition of the order topology defined on a total order (https://en.wikipedia.org/wiki/Order_topology), I realized I needed a generalization to preorders. So ultimately the question: Is there a generalization of the order topology to preorders. If so, what is it? If not, what are some workarounds?



Some motivation:
My idea is to use “dense” preorders to model cause and effect where a<=b iff a causes b. The topology would make it possible to capture the idea that it is posible certian events are “closer” to directly causing another event.










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    0












    $begingroup$


    While looking at the definition of the order topology defined on a total order (https://en.wikipedia.org/wiki/Order_topology), I realized I needed a generalization to preorders. So ultimately the question: Is there a generalization of the order topology to preorders. If so, what is it? If not, what are some workarounds?



    Some motivation:
    My idea is to use “dense” preorders to model cause and effect where a<=b iff a causes b. The topology would make it possible to capture the idea that it is posible certian events are “closer” to directly causing another event.










    share|cite|improve this question









    $endgroup$















      0












      0








      0





      $begingroup$


      While looking at the definition of the order topology defined on a total order (https://en.wikipedia.org/wiki/Order_topology), I realized I needed a generalization to preorders. So ultimately the question: Is there a generalization of the order topology to preorders. If so, what is it? If not, what are some workarounds?



      Some motivation:
      My idea is to use “dense” preorders to model cause and effect where a<=b iff a causes b. The topology would make it possible to capture the idea that it is posible certian events are “closer” to directly causing another event.










      share|cite|improve this question









      $endgroup$




      While looking at the definition of the order topology defined on a total order (https://en.wikipedia.org/wiki/Order_topology), I realized I needed a generalization to preorders. So ultimately the question: Is there a generalization of the order topology to preorders. If so, what is it? If not, what are some workarounds?



      Some motivation:
      My idea is to use “dense” preorders to model cause and effect where a<=b iff a causes b. The topology would make it possible to capture the idea that it is posible certian events are “closer” to directly causing another event.







      general-topology relations order-theory order-topology






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      asked Jan 17 at 14:46









      user512716user512716

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          Define for each $x in X$, the lower and upper sets $L(x) = {y in X: y < x}$ and $U(x) = {y in X: y > x}$. By definition all such sets together form a subbase for the order topology when $(X,<)$ is a linear order.



          So if you want to generalise to a partial order $(X,le)$, just define $x < y$ as $ x le y$ and $x neq y$ and use the same subbase.






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            $begingroup$

            There is the Alexandrov topology on a pre-ordered set.

            It is not a generalization of the order topology you link to, but it might be what you're looking for






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              $begingroup$

              Define for each $x in X$, the lower and upper sets $L(x) = {y in X: y < x}$ and $U(x) = {y in X: y > x}$. By definition all such sets together form a subbase for the order topology when $(X,<)$ is a linear order.



              So if you want to generalise to a partial order $(X,le)$, just define $x < y$ as $ x le y$ and $x neq y$ and use the same subbase.






              share|cite|improve this answer









              $endgroup$


















                1












                $begingroup$

                Define for each $x in X$, the lower and upper sets $L(x) = {y in X: y < x}$ and $U(x) = {y in X: y > x}$. By definition all such sets together form a subbase for the order topology when $(X,<)$ is a linear order.



                So if you want to generalise to a partial order $(X,le)$, just define $x < y$ as $ x le y$ and $x neq y$ and use the same subbase.






                share|cite|improve this answer









                $endgroup$
















                  1












                  1








                  1





                  $begingroup$

                  Define for each $x in X$, the lower and upper sets $L(x) = {y in X: y < x}$ and $U(x) = {y in X: y > x}$. By definition all such sets together form a subbase for the order topology when $(X,<)$ is a linear order.



                  So if you want to generalise to a partial order $(X,le)$, just define $x < y$ as $ x le y$ and $x neq y$ and use the same subbase.






                  share|cite|improve this answer









                  $endgroup$



                  Define for each $x in X$, the lower and upper sets $L(x) = {y in X: y < x}$ and $U(x) = {y in X: y > x}$. By definition all such sets together form a subbase for the order topology when $(X,<)$ is a linear order.



                  So if you want to generalise to a partial order $(X,le)$, just define $x < y$ as $ x le y$ and $x neq y$ and use the same subbase.







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered Jan 17 at 18:52









                  Henno BrandsmaHenno Brandsma

                  111k348118




                  111k348118























                      0












                      $begingroup$

                      There is the Alexandrov topology on a pre-ordered set.

                      It is not a generalization of the order topology you link to, but it might be what you're looking for






                      share|cite|improve this answer









                      $endgroup$


















                        0












                        $begingroup$

                        There is the Alexandrov topology on a pre-ordered set.

                        It is not a generalization of the order topology you link to, but it might be what you're looking for






                        share|cite|improve this answer









                        $endgroup$
















                          0












                          0








                          0





                          $begingroup$

                          There is the Alexandrov topology on a pre-ordered set.

                          It is not a generalization of the order topology you link to, but it might be what you're looking for






                          share|cite|improve this answer









                          $endgroup$



                          There is the Alexandrov topology on a pre-ordered set.

                          It is not a generalization of the order topology you link to, but it might be what you're looking for







                          share|cite|improve this answer












                          share|cite|improve this answer



                          share|cite|improve this answer










                          answered Jan 17 at 15:28









                          amrsaamrsa

                          3,6702618




                          3,6702618






























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