text/a_inf_blob.tex
changeset 550 c9f41c18a96f
parent 544 24be062a87a1
child 555 11532ce39ec0
equal deleted inserted replaced
549:4d2dad357a49 550:c9f41c18a96f
   280 In the second approach we use a decorated colimit (as in \S \ref{ssec:spherecat}) 
   280 In the second approach we use a decorated colimit (as in \S \ref{ssec:spherecat}) 
   281 and various sphere modules based on $F \to E \to Y$
   281 and various sphere modules based on $F \to E \to Y$
   282 or $M\to Y$, instead of an undecorated colimit with fancier $k$-categories over $Y$.
   282 or $M\to Y$, instead of an undecorated colimit with fancier $k$-categories over $Y$.
   283 Information about the specific map to $Y$ has been taken out of the categories
   283 Information about the specific map to $Y$ has been taken out of the categories
   284 and put into sphere modules and decorations.
   284 and put into sphere modules and decorations.
   285 \nn{...}
   285 \nn{just say that one could do something along these lines}
   286 
   286 
   287 %Let $F \to E \to Y$ be a fiber bundle as above.
   287 %Let $F \to E \to Y$ be a fiber bundle as above.
   288 %Choose a decomposition $Y = \cup X_i$
   288 %Choose a decomposition $Y = \cup X_i$
   289 %such that the restriction of $E$ to $X_i$ is a product $F\times X_i$,
   289 %such that the restriction of $E$ to $X_i$ is a product $F\times X_i$,
   290 %and choose trivializations of these products as well.
   290 %and choose trivializations of these products as well.
   441 
   441 
   442 It is now easy to see that $\psi\circ\phi$ is the identity on the nose.
   442 It is now easy to see that $\psi\circ\phi$ is the identity on the nose.
   443 Another acyclic models argument shows that $\phi\circ\psi$ is homotopic to the identity.
   443 Another acyclic models argument shows that $\phi\circ\psi$ is homotopic to the identity.
   444 (See the proof of Theorem \ref{thm:product} for more details.)
   444 (See the proof of Theorem \ref{thm:product} for more details.)
   445 \end{proof}
   445 \end{proof}
   446 
       
   447 \nn{maybe should also mention version where we enrich over
       
   448 spaces rather than chain complexes;}
       
   449 
       
   450