errata

errata

[Eduardo Dubuc]

in my posting:

"this is essentially the difference between filterness and cofilterness,
with all what it means"

it should be:

"this is essentially the difference between filterness and
pseudofilterness, with all what it means"

RE: errata

[Marta Bunge]

Even in the locally connected case there are several non isomorphic trivialization structures. The difference is that, in that case, there is a canonical one.
> Date: Wed, 6 Oct 2010 09:34:51 -0300
> From: edubuc@dm.uba.ar
> To: edubuc@dm.uba.ar
> CC: categories@mta.ca
> Subject: categories: errata
> 
> 
>>
>> The difference is only manifest when the space B is not locally
>> connected. In
>> this case we may have homeomorphisms from X to X over B which do not
>> preserve
>> this structure (Spanier, Algebraic Topology).
>>
>>
> 
> is not quite it should be,
> 
> there is a clear notion of isomorphism of trivialization structure, and  a same
> space X over B may have non isomorphic structures. Alternatively, a continuous
> function over B does not necessarily preserve the trivialization structures.
> 
> however, if B is locally connected, trivialization structures are like a pure
> property of X.
> 

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errata

[Eduardo J. Dubuc]

>
> The difference is only manifest when the space B is not locally
> connected. In
> this case we may have homeomorphisms from X to X over B which do not
> preserve
> this structure (Spanier, Algebraic Topology).
>
>

is not quite it should be,

there is a clear notion of isomorphism of trivialization structure, and a same
space X over B may have non isomorphic structures. Alternatively, a continuous
function over B does not necessarily preserve the trivialization structures.

however, if B is locally connected, trivialization structures are like a pure
property of X.


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Re: errata

[Michael Shulman]

And of course instead of "evil" one could say "treif".

On Tue, Sep 14, 2010 at 3:10 PM, David Roberts
<droberts@maths.adelaide.edu.au> wrote:
> Actually this is the sort of thing I was trying to think of - it
> shifts the focus to the positive (we can talk about kosher, as opposed
> to 'non-evil'). It also has an element of incongruity, so that like
> 'evil' people stop for a moment and go 'hang on...'. And like the
> concept of kosher, people who are not that way inclined can live quite
> happily without it.
>
> David
>
>
> On 14 September 2010 10:32, Eduardo J. Dubuc <edubuc@dm.uba.ar> wrote:
>> of course,   I meant  "not kosher' or "non kosher"

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Re: errata

[Eduardo J. Dubuc]

the problem is that "kosher" (or not kosher) is a word much more universally
known than "trefe".   e.d.

Robert Knighten wrote:
> Eduardo J. Dubuc writes:
> > of course,   I meant  "not kosher' or "non kosher"
>
> The word you want is "trefe" :-)
>
> -- Bob
>


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Re: errata

[David Roberts]

Actually this is the sort of thing I was trying to think of - it
shifts the focus to the positive (we can talk about kosher, as opposed
to 'non-evil'). It also has an element of incongruity, so that like
'evil' people stop for a moment and go 'hang on...'. And like the
concept of kosher, people who are not that way inclined can live quite
happily without it.

David


On 14 September 2010 10:32, Eduardo J. Dubuc <edubuc@dm.uba.ar> wrote:
> of course,   I meant  "not kosher' or "non kosher"
>
>

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errata

[Eduardo J. Dubuc]

of course,   I meant  "not kosher' or "non kosher"


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