On 09 May 2012, at 17:09, R AM wrote:

PM, Bruno MarchalYes."Nothing", in set theory, would be more like an empty *collection*of sets, or an empty "universe" (a model of set theory), except thatin first order logic we forbid empty models (so that AxP(x) ->ExP(x) remains valid, to simplify life (proofs))."nothing" could also be obtained by removing the curly brackets fromthe empty set {}.

`Noooo... Some bit of blank remains. If it was written on hemp, you`

`could smoke it. That's not nothing!`

`Don't confuse the notion and the symbols used to point to the notion.`

`Which you did, inadvertently I guess.`

`{ } is a set and "{ }" is a string with 3 symbols, ... which should be`

`differentiated even from the paper and ink, or stable picture on a`

`screen, representing physically the symbols to you, and then from the`

`image made by your brain, and the neuronal 'music' trigged by it, and`

`the consciousness filtered locally by the process, etc.`

Or removing the (empty) container. I guess this would be equivalentto "removing" space from the universe. Except that this doesn't makeany sense in Set Theory (maybe it doesn't make any sense in realityeither).Still, {} is some sort of nothing in Set Theory,

`Sure, like 0 is some sort of nothing in Number theory, and like`

`quantum vacuum is some sort of nothing in QM. Nothing is a theory`

`dependent notion. (Not so for the notion of computable functions).`

`Extensionally, the UD is a function from nothing (no inputs) to`

`nothing (no outputs), but then what a worker!`

Extensionally it belongs to { } ^ { }. It is a function from { } to { }.

`But that is a bit trivial, I think. It is due to the fact that`

`computability theory is not dimensional. Dimensions also have to be`

`derived from the internal points of view (with comp), like the real`

`and complex numbers and the physical laws.`

given that it is what is left after all that is allowed to beremoved, is removed.

OK. Bruno

Ricardo. Bruno http://iridia.ulb.ac.be/~marchal/ --You received this message because you are subscribed to the GoogleGroups "Everything List" group.To post to this group, send email to everything-list@googlegroups.com.To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com.For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.--You received this message because you are subscribed to the GoogleGroups "Everything List" group.To post to this group, send email to everything-list@googlegroups.com.To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com.For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.

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