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Bob
12:21 AM
good evening
 
 
1 hour later…
1:46 AM
good evening to you
 
Bob
2:19 AM
good night
 
2:32 AM
Howdy @copper
 
2:56 AM
Bonsoir @TedShifrin!
 
3:06 AM
I'm currently reading Narahimhan's complex analysis textbook. It's pretty good to me
 
3:50 AM
As I remember, it had some really unusual stuff in it. I taught part of it, but didn’t read most.
 
Corona theorem for example?
 
any complex text that starts with the Wirtinger derivatives is not elementary in my mind
 
It’s definitely a graduate text.
I used his differential geometric proof of big Picard.
 
4:20 AM
Makes sense. My complex development stopped at Nevanlinna Pick.
 
 
1 hour later…
C7X
5:36 AM
@RE60K @RE60K The support of a function $e$ is the set $\{x\in dom(e)\mid e(x)\neq 0\}$. Probably will depend on the context of the paper, but if for each vertex $v$ there's an associated function $e$ I'd guess $e$ maps each vertex to the number of edges connecting $v$ to the vertex. Then the support of $e$ (function $e$ chosen when working with vertex $v$) would be the set of vertices connected to $v$
 
 
2 hours later…
7:55 AM
Does there exists any injective ring homomorphism from $C([0, 1], \mathbb{R}) $ to $C(K, \mathbb{R}) $ ? ($K\subset [0, 1] $ is the Cantor set)
 
8:35 AM
is X\wedge n=max(X,n) or min(X,n)?
 
really up to whoever is defining it, but min would be standard
 
okey thank you
 
9:29 AM
@TedShifrin There's a complex analysis textbook by Krantz that has a geometric viewpoint. But I think you already aware of it.
 
9:51 AM
I read the answer of poission distribution but I am bit confused about the parameter lambda
It is mean right?
The probability of exactly one occurrence in a sufficiently short subinterval
of length h is approximately λh.
I don't get what h is and why is lambda*h a probability
and poission distribution is a pmf and lambda*h is also a pmf
I don't get it
I see some article mentioning lambda is rate
 
 
2 hours later…
12:19 PM
@SouravGhosh There is a surjective continuous map $K\rightarrow[0,1]$. a) Do you know this? b) Can you see what this has to do with your question?
 
12:32 PM
@NotTfue In the answer I mentioned in my previous reply, it is mentioned that $v$ was the "expected number of decay events ... in a second". In the Poisson process, there is a given sample space (in the decay example, it is a second).
Given the expected number of occurrences in the sample space, $\lambda$, Poisson's Formula says that the probability of $n$ occurrences happening in the sample space is $\frac{\lambda^n}{n!}e^{-\lambda}$.
If the sample space is an amount of time, $\lambda$ is the expected rate of occurrences in that amount of time.
 
1:23 PM
Can I do the following proof to show that the closure of an open ball is contained in the closed ball.
Let me pick y\in \bar(B(x,r)) in the closure. Then I know that this is equivalent to say that for all $\epsilon >0$ B(y,\epsilon)\cap B(x,r)\neq \emptyset. but this means that y\in B(x,r)\subset \bar(B)(x,r).
 
 
3 hours later…
4:06 PM
@anak do I have to specify $e(-1)=0$ and $e(1)=0$ for the embedding?
 
 
2 hours later…
6:18 PM
@Wave please use mathjax, otherwise it is hard to read
 
6:41 PM
@copper.hat sorry I don't know what mathjax is and how to write it and how to read it
 
7:06 PM
3763
Q: MathJax basic tutorial and quick reference

MJD(Deutsch: MathJax: LaTeX Basic Tutorial und Referenz) To see how any formula was written in any question or answer, including this one, right-click on the expression and choose "Show Math As > TeX Commands". (When you do this, the '$' will not display. Make sure you add these: see the next point...

 
7:17 PM
G’day @robjohn
 
@TedShifrin hello. We are back from our vacation. The temperature is much hotter here than in Mammoth.
96° here and 68° in Mammoth
 
Yeah, the heat wave is back ;(
Did you drive to Manmoth or fly?
 
8:07 PM
We drove. We like the scenery and the drive. First time for our dog, and she liked it.
 
8:22 PM
hi, i wanted to ask about a proof that is in my real analysis book to prove the archimedean property. is takes the approach to, for contradiction, assume that N is bounded above. then, say we have b := sup(N), then b-1 cannot be an upper bound, so there exists an m in N such that m > b-1, then add one to both sides and this contradicts b being an upper bound
however, i dont understand why there has to be an m in N st m > b-1
 
What does it mean that $b-1$ is NOT.
An upper bound. Can’t edit. Grrr.
 
sorry i dont quite understand your question
 
You said $b-1$ cannot be an upper bound. What does that mean?
 
i think the idea is if b is the supremum, b - 1 cant be an upper bound
where being an upper bound is something like there is no element in the set larger than the upper bound - lemme look up the exact def
 
Agreed. So figure out what failure to be an upper bound means.
 
8:33 PM
if there exists a b in S such that x is less than or equal to b for all x in E , then we say E is bounded above and b is an upper bound of E
is the exact def
 
now read what I typed above
 
oh oh is it like if b had nothing above it then it would be an upper bound
 
$b-1$, right.
 
got it got it thanks
 
good.
 
 
2 hours later…
10:53 PM
@robjohn OK I see I misunderstood slightly I think I get it now.
 

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