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Peter May
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I would like to just comment but don't see how. Christian, here's an answer to your last question. For based spaces, you can just do what you want by hand, as Fernando suggested, taking care to use disjoint basepoints to make your attaching maps of $A$ based. You are right to complain that the interplay of $h$ and $q$-model structures is not obvious. Based spaces are of coursescourse spaces over and under a point. In ``Parametrized homotopy theory'', Sigurdsson and I generalize to parametrized spaces, which are spaces over and under a give space, and then the combination of $h$, $q$, and related model structures is surprisingly delicate. In that book, the answer to theyour original question you asked is axiomatized in a general model categorical context in 5.4.1 (see (v)) and the axioms are verified for parametrized spaces in 5.4.9. But that is like hitting a thumb tack with a sledge hammer. Maybe it will help to add that in the direct argument you do need to know that a wedge of weak equivalences is a weak equivalence, and that uses the well-pointed hypothesis.

I would like to just comment but don't see how. Christian, here's an answer to your last question. For based spaces, you can just do what you want by hand, as Fernando suggested, taking care to use disjoint basepoints to make your attaching maps of $A$ based. You are right to complain that the interplay of $h$ and $q$-model structures is not obvious. Based spaces are of courses spaces over and under a point. In ``Parametrized homotopy theory'', Sigurdsson and I generalize to parametrized spaces, which are spaces over and under a give space, and then the combination of $h$, $q$, and related model structures is surprisingly delicate. In that book, the answer to the question you asked is axiomatized in a general model categorical context in 5.4.1 (see (v)) and the axioms are verified for parametrized spaces in 5.4.9. But that is like hitting a thumb tack with a sledge hammer.

I would like to just comment but don't see how. Christian, here's an answer to your last question. For based spaces, you can just do what you want by hand, as Fernando suggested, taking care to use disjoint basepoints to make your attaching maps of $A$ based. You are right to complain that the interplay of $h$ and $q$-model structures is not obvious. Based spaces are of course spaces over and under a point. In ``Parametrized homotopy theory'', Sigurdsson and I generalize to parametrized spaces, which are spaces over and under a give space, and then the combination of $h$, $q$, and related model structures is surprisingly delicate. In that book, the answer to your original question is axiomatized in a general model categorical context in 5.4.1 (see (v)) and the axioms are verified for parametrized spaces in 5.4.9. But that is like hitting a thumb tack with a sledge hammer. Maybe it will help to add that in the direct argument you do need to know that a wedge of weak equivalences is a weak equivalence, and that uses the well-pointed hypothesis.

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Peter May
  • 30.4k
  • 3
  • 96
  • 140

I would like to just comment but don't see how. Christian, here's an answer to your last question. For based spaces, you can just do what you want by hand, as Fernando suggested, taking care to use disjoint basepoints to make your attaching maps of $A$ based. You are right to complain that the interplay of $h$ and $q$-model structures is not obvious. Based spaces are of courses spaces over and under a point. In ``Parametrized homotopy theory'', Sigurdsson and I generalize to parametrized spaces, which are spaces over and under a give space, and then the combination of $h$, $q$, and related model structures is surprisingly delicate. In that book, the answer to the question you asked is axiomatized in a general model categorical context in 5.4.1 (see (v)) and the axioms are verified for parametrized spaces in 5.4.9. But that is like hitting a thumb tack with a sledge hammer.