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Topic: Zero set
Replies: 7   Last Post: May 31, 2012 3:12 AM

 Messages: [ Previous | Next ]
 Brian M. Scott Posts: 1,289 Registered: 12/6/04
Re: Zero set
Posted: May 30, 2012 5:57 AM

On Wed, 30 May 2012 01:38:35 -0700, William Elliot
<marsh@panix.com> wrote in
<news:Pine.NEB.4.64.1205300128060.28313@panix2.panix.com> in
sci.math,alt.algebra.help:

> On Wed, 30 May 2012, Butch Malahide wrote:

>> On May 30, 2:18 am, William Elliot <ma...@panix.com> wrote:

>>> If A is a zero subset of S, is cl S\A a zero subset?

>> Let S be a totally ordered set of order type omega_1 + 1
>> + omega^* with the order topology, and let A be the
>> subset consisting of the first omega_1 + 1 elements of
>> S. It seems to me that A is a zero set, but cl S\A is
>> not a zero set.

> What's omega^*? The reverse of omega_1?

No: it's the reverse of omega.

[...]

Date Subject Author
5/30/12 William Elliot
5/30/12 Butch Malahide
5/30/12 Butch Malahide
5/30/12 William Elliot
5/30/12 Brian M. Scott
5/30/12 Butch Malahide
5/31/12 William Elliot
5/31/12 Butch Malahide