Sujet : Re: More complex numbers than reals?
De : ben (at) *nospam* bsb.me.uk (Ben Bacarisse)
Groupes : sci.mathDate : 10. Jul 2024, 00:45:15
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <878qyap1tg.fsf@bsb.me.uk>
References : 1 2 3 4 5
User-Agent : Gnus/5.13 (Gnus v5.13)
"Chris M. Thomasson" <
chris.m.thomasson.1@gmail.com> writes:
On 7/9/2024 10:30 AM, Ben Bacarisse wrote:
WM <wolfgang.mueckenheim@tha.de> writes:
Le 09/07/2024 à 14:37, Ben Bacarisse a écrit :
>
A mathematician, to whom this is a whole new topic, would start by
asking you what you mean by "more". Without that, they could not
possibly answer you.
>
Good mathematicians could.
>
So, what do you mean by "more" when applied to
sets like C and R?
>
Proper subsets have less elements than their supersets.
>
Let's see if Chris is using that definition. I think he's cleverer than
you so he will probably want to be able to say that {1,2,3} has "more"
elements than {4,5}.
>
I was just thinking that there seems to be "more" reals than natural
numbers. Every natural number is a real, but not all reals are natural
numbers.
You are repeating yourself. What do you mean by "more"? Can you think
if a general rule -- a test maybe -- that could be applied to any two
set to find one which has more elements?
So, wrt the complex. Well... Every complex number has a x, or real
component. However, not every real has a y, or imaginary component...
>
Fair enough? Or still crap? ;^o
So you are using WM's definition based on subsets? That's a shame. WM
is not a reasonable person to agree with!
One consequence is that you can't say if the set of even numbers has
more or fewer elements than {1,3,5} because {1,3,5} is not a subset of
the even numbers, and the set of even numbers is not a subset of
{1,3,5}. They just can't be compared using your (and WM's) notion of
"more".
-- Ben.