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Akiva Weinberger
11:07 PM
It's rare that I can get distracted by two separate pianos in a row
Ted Shifrin
Hi @Kasmir and DogAteMy ... you're walking down a row of pianos, DogAteMy?
Kasmir Khaan
Ted :D
I am doing the first isomorphism theorem
I got a bit stuck
Ted Shifrin
Nah.
Kasmir Khaan
Kinda need a dos of your wisdom :D
Hmm ._.
Can you put it in words the result of that theorem ?
Ted Shifrin
Why don't you try?
Kasmir Khaan
11:11 PM
well so far this is what i got
we start with surjective hom
we can allways do that ,f: G--->H, if we take only the image of f
what we do next we take the map Pi: G-->G/K
Ted Shifrin
What's $K$?
Kasmir Khaan
K is the kernel
Ted Shifrin
OK.
Kasmir Khaan
and another map f* : G/K ---> H
Daminark
Hai
Ted Shifrin
11:14 PM
Huh? Where did that come from?
hi Demonark
Kasmir Khaan
what did what come from ?
Ted Shifrin
$f^*$
Kasmir Khaan
You mean the notation is bad ? or the map is wrong
i meant f bar
just something different from f
Ted Shifrin
You just said we take another map $f^*$. What is it?
Yeah, star isn't good. $\bar f$ is better.
Kasmir Khaan
okay should I continue ? or i did not answer yet?
$\bar f$ : G/K ---> H
Ted Shifrin
11:16 PM
You didn't answer. You just take any old $\bar f$, or is it made up using $f$ somehow?
Kasmir Khaan
well
$\bar f$ is an isomorphism
Ted Shifrin
defined how?
Kasmir Khaan
By taking cosets of K
Ted Shifrin
that's elements of $G/K$
Kasmir Khaan
Yes we start from G and we collapse the elements of G into G/H
equivalence classes
Ted Shifrin
11:18 PM
What does this have to do with $f$?
Kasmir Khaan
I am not sure I understand the question but , f was not 1-1
but when we collaspe G into G/H
Ted Shifrin
You're supposed to define $\bar f$ for me.
Kasmir Khaan
ah okay
$\bar f$ : aK --> a
Ted Shifrin
No.
Kasmir Khaan
take a coset to one representative
okay let me think
Ted Shifrin
11:20 PM
You're defining a homomorphism from $G/K$ to $H$.
Kasmir Khaan
but that is more than hom
Ted Shifrin
One step at a time.
Kasmir Khaan
Okay
I was lost in notation, wrote H instead of K ( noticed that just now )
Okay let me see how to define $\bar f$
Ted Shifrin
You need to read your book and study it. And this is all in my book, too, of course.
Read and study with pencil ... work out all the details for yourself (without reading the book).
Kasmir Khaan
I did that but maybe i need second read
am not sure what your question was tbh
you wanted me to define f bar
Akiva Weinberger
11:24 PM
@TedShifrin Can I PM you in a minute? (I.E. Open up a private room)
Kasmir Khaan
the elements of G/K are of the from aK , a in G
Ted Shifrin
OK, DogAteMy ...
So you need to know what $\bar f(aK)$ is, @Kasmir, and you need to know why (1) this is well-defined, (2) this defines a homomorphism, and (3) it is a bijection.
You need to work this all out for yourself.
Kasmir Khaan
aK* bK = ab K
Is that what you wanted?
Ted Shifrin
No. Read what I wrote and go do it.
Kasmir Khaan
I ll do that now
Ted Shifrin
11:26 PM
I don't have the patience to sit here through this.
You need to prepare.
Kasmir Khaan
I understand that and thanks for help
Yes I know its all fuzzy with these defintions
and notation
Ill have a second read and come back
Ted Shifrin
I have lots of examples in my book.
Kasmir Khaan
am looking at it now =p
Semiclassical
hi chat
Daminark
11:39 PM
Hullo
Ted Shifrin
11:59 PM
hi Demonark — how're classes?
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