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12:08 AM
Mathematics of breaking speghetti
 
12:27 AM
@Secret You misspelled spaghetti.
 
LOL, @Jasper, you're quite predictable :P
 
@TedShifrin Yes, I am a constant.
 
well, no
you have your aspects of chaos ... but many things are approximately constant
 
what about me
 
no comment
 
12:31 AM
Looks like the appointment of Brett to the Supreme Court has caused quite a drama.
 
he hasn't been appointed
 
The lying a-hole will be confirmed. A page out of the orange narcissist's playbook. ... OK, I'm done.
I hate having to be more responsible.
 
I am actually getting amused by American politics. The past two years actually.
 
It's damn scary, @Jasper. Far from amusing.
 
I also don't understand why many British politicians still insist on Brexit when it is clear Brexit hurts.
 
12:33 AM
Yup ... the world is disintegrating into racism and nationalism.
But economically, of course
 
You know, I wanted to solve the problems of the world, but now I just want to solve my own problems, because I still have not solved them yet.
 
If I had as my goal to solve the world's problems, I would have committed suicide decades ago.
 
@TedShifrin @JasperLoy generally, how does one parametrize a space
 
I figured trying to teach a small part of the world mathematics in a good way was a better goal — and being a good cook :P
 
@Ultradark You mean a curve or surface?
 
12:36 AM
Depends how complicated the space is.
Some (copies of vector spaces) you can do easily. Others are almost impossible.
 
A set of curves in a two dimensional space
 
Plus a lot are infinite-dimensional.
What klnd of curves?
 
so the conditions are
 
That's a very infinite-dimensional space, regardless.
 
Well, you just stare very hard at the curve and do lots of thinking.
 
12:37 AM
That's only one point in this YUGE space, Jasper :)
 
that the curves have to essentially "start" at the point (0,0) and "end" at (1,1)
 
Are they continuous? smooth?
 
definitely continuous
and smooth yeah
and also they have to stay inside the unit square. So I guess boundedness is another condition
 
So you look at $C^\infty$ maps from $[0,1]$ to $\Bbb R^2$ with the two conditions $f(0)=(0,0)$ and $f(1)=(1,1)$. Then there's an issue with reparametrizing the same set. But basically it's that infinite-dimensional Frechet space.
Oh, that restricts you to some subset, sorta yucky 'cuz of $\le$ and $\ge$ not meaning open.
 
what?
I understand the first part
 
12:41 AM
You're saying $0\le f_i(t)\le 1$ for $i=1,2$.
 
would it be "nicer" if they were open
 
yeah, if you want to do calculus on this space.
It's still a very HUGE space.
 
how can I restrict it further to make it more manageable
 
It's most likely going to be infinite-dimensional, regardless. This is where the study of calculus of variations comes in. Trying to do max/min problems in infinite dimensions.
 
oh, also the curves cannot intersect, so doesn't that comprise a notion of an ordered set
 
12:46 AM
Nah. What do you mean "the curves cannot intersect"?
We're looking at all curves from one point to another. We don't have a specific family.
 
but to restrict it further I could look at a family right
and a family would not intersect
 
So, you basically want a foliation of the square (minus the two points), with the property that all leaves go through the two points. This comes from a $1$-form with the property that it vanishes at the two points and is non-zero elsewhere.
 
Yes..I'm not sure I understand the concept of "leaves" though
 
so $P(x,y)dx+Q(x,y)dy$ with $P$ and $Q$ both vanishing precisely at the two points.
Those are the integral curves of the differential equation $Pdx+Qdy=0$.
So far I see no way to keep the curves inside the square.
 
ah okay
couldn't you just impose some boundary conditions?
 
12:53 AM
Well, probably that on the boundary square you have to be tangent to the boundary.
so, e.g., when $x=0$ or $1$ , then $Q=0$, and when $y=0$ or $1$, then $P=0$.
OK, that's not unreasonable.
And those intersect in the conditions that I already specified, that $P(0,0)=Q(0,0)=P(1,1)=Q(1,1)=0$.
 
okay, so you wrote the diff eq in condensed form
$P(x,y)dx+Q(x,y)dy=0$
So do I have to find $P(x,y)$ and $Q(x,y)$ now?
I think they would both be increasing functions
 
no, all the functions $P,Q$ with the properties I've specified will give you answers to your question. So you have a more handle-able parameter space: smooth functions $P(x,y)$, $Q(x,y)$ with the boundary conditions.
 
oh okay
 
No, no, remember $P$ vanishes on the top and bottom and $Q$ vanishes on the left and right.
But otherwise they're arbitrary.
 
so I can test out specific situations with this model
 
1:01 AM
Yup.
With computers, you should be able to do zillions of examples.
 
@TedShifrin Good luck.
 
Not my problem, Nick. It's Ultradark's experimentations.
 
That reminds me. I ought to ask. Is there any matlab alternative where I can play around with hyper geometry?
 
I don't know what the question is, but I have no idea.
 
Octave, is the free version of Matlab, if that's helpful
 
1:33 AM
Did someone say free?
 
Demonark has certain Pavlovian responses.
 
@TedShifrin morning
 
hi @Faust ... you alive?
 
yeah, any chance u have some free time on zaturday?
 
Probably. I have my usual document-cam calculus tutorial 3-4.
 
1:39 AM
any chance you be intrested in teaching some manifold stuff?
 
Why, what's happening Sat?
Oh, did he finally assign something?
 
well yeah but we just got to something intresting then stopped
 
stopped and did what?
 
was wondering if you could teach us some more about cohomology
 
@Daminark Maybe you will see that very often, free things are not so good. =)
 
1:40 AM
stopped and went home
 
Yo @Faust have you gotten married?
 
no i am not married, still have a fiance though
 
fiancée, in your case
 
Yeah I remember, which is why I asked. I thought you would have 10 kids by now, lol.
 
you haven't learned enough to talk about cohomology yet, @Faust ... you haven't done integrals or pullbacks or ...
 
1:43 AM
aww
imersions then?
 
you haven't defined manifolds, or have you?
 
thats next class i guess
 
so what did he do that was interesting and then stopped?
 
cohomology
 
oh ... but you don't have tools to do much about it
I guess we could do a little
like cohomology of the circle
did he do that?
 
1:45 AM
please would be so coool
no nothing
 
oh, ok ...
 
just talked about it and said that the
omega function was one
 
1-form, actually
 
yeah he stopped part way through the explanation
i got a friend form class whos going to be over on saturday
 
yeah, we can do that without much more than multivariable calc stuff
like when on Sat?
 
1:47 AM
whenever works for you
 
maybe early afternoon ... not sure yet
 
we've been doing some algebraic topology
so its intresting to see something similiar show up
ok that would be great ^^
 
1:59 AM
Oh yeah in my analysis pset once we basically computed cohomology of the circle, that was a lot of fun
 
The $n$-sphere is much more interesting :P
You can do it inductively, but you need $S^1$ to start.
 
Is it an argument that passes through suspension or is it more directly a forms/de Rham thing?
 
Mayer-Vietoris with forms
 
Ah
So you do the thing where you write it as a union of two disks whose intersection is an n-1 sphere?
 
thickened up, yeah
and you use partitions of unity
bye
 
2:02 AM
Lol I need to learn partitions of unity at some point. And see you!
 
 
1 hour later…
3:11 AM
@Daminark Take a noodle and stretch it out. Then chop it into pieces. That is a partition of unity.
 
3:30 AM
What needs to be shown in order to confirm that a collection of open sets is a topology?
I believe I know, but I want to be certain
 
3:52 AM
confirm the axioms of being a topology...
 
I wish I could do math instead of school. I just want to work on my proof, but I have homework.
 
0
Q: A problem on Sobolev Hilbert space using Fourier transform, from PDE book by Evans.

Rajesh DachirajuLet $u \in H^s(\mathbb{R}^n)$.Given that $s \in \mathbb{N}$ and $s>\frac{n}{2}$. I need to prove that $$u\in L^{\infty}(\mathbb{R}^n)$$ and $$\|u\|_{L^{\infty}(\mathbb{R}^n)} \le C\|u\|_{H^s(\mathbb{R}^n)}$$ $C$ depending only on $s$ and $n$. Appreciate your help in getting some hints on provi...

 
Anyone know some good set theory books? I'm currently reading Hrbeck
*Hrbacek
 
So, just show that X and the empty set are open, that an arbitrary union of open sets is open, and that a finite intersection of open sets is open?
 
4:08 AM
Can anyone tell me the fastest way to deduce which of the 4 to is the correct answer? I have no clue other than doing truth tables but its MCQ ...
 
Big challenge ongoing:
Finding a suitable projective geometry so that 3 levels of infinity can be simultaneously shown in one picture
 
@PrashinJeevaganth Why would you complete a truth table for that?
@PrashinJeevaganth It seems like something you could do in your head.
 
@PrashinJeevaganth Well $p\leftrightarrow q \equiv (p\to q)\wedge (q\to p)$, and do you know any equivalent identities to these latter two?
 
Purple regions are infintesimals
 
@CaptainAmerica16 Sorry do u mind sharing how would u do this in your head? I'm a novice
I can't see the Latex ...
 
4:14 AM
 
@PrashinJeevaganth I don't really know how to explain it, but if you know the meaning of the symbols, then you just have to find the logical statements. It asks for which is equivalent to $p$ if and only if $q$, so the only ones that work are I and II. They read: 1. (Not $p$ or $q$) and ($p$ or Not $q$) 2. (Not $p$ and Not $q$) or ($p$ and $q$). If you think of it like that, the logical equivalency becomes more obvious.
 
ok how does this work... bookmark the start jar?
 
@PrashinJeevaganth Yep bookmark it, and then come back here and click the bookmark
 
@PrashinJeevaganth Yeah, just bookmark and then click on it.
 
Alright got it
Hmm ok I only know the first one in my head
 
4:19 AM
@PrashinJeevaganth Ah, so that seems like part of the issue.
 
Personally I don't think avoiding learning how to manipulate these expressions is a great idea :P
 
@PrashinJeevaganth I guess I just got used to being lazy...
 
Surely a final exam will have convoluted expressions and require you to justify your answer
@CaptainAmerica16 To me it seems like you are doing a tremendous amount of work :P
Seems anti-lazy
 
Well, actually the convoluted expressions only appear in the MCQ, the others are just spoken in English, either which I also need help ...
 
Is $(1-x)^{n/2}=x^n$ always equal to $1/\phi$, where $\phi$ is the golden ratio and $n$ is some positive integer?
 
4:21 AM
@AlexClark Just working from memory? I suppose I get what you mean, I'm weird.
@AlexClark Care to take it from here? I have homework.
 
Is it wise to forcefully expand it into 4 terms for the 2nd option?
 
@Semiclassical Hi Semiclassical ...
 
do u have any insights to give on my latest question on how to expand it?
 
4:26 AM
you can take both sides to the power of $2/n$ and get $1-x=x^2$
So the integer $n$ is actually irrelevant
 
Currently testing: Blowing up the pixel to 3 times its size, so that a sequence that approach an asymptote can be digitalised
 
@CaptainAmerica16 Hrbacek/Jech is the best set theory book I know of, but you should not read this book if you don't know how to write proofs yet.
 
Wow, I think I expanded that tedious logical statement in (II) and somehow made it without errors...
 
for example $(1-x)^5=x^{10}$ yields a real solution $x=1/\phi$.
 
@Rithaniel Just show that the definitions for a topology hold.
@Rithaniel Yes.
 
4:31 AM
(Yeah, already wrote down my proof. I was being excessively cautious because the problem seemed far easier than the usual in that class.)
 
@JasperLoy I know how to write proofs. Guess I'll stick with it then. Thanks for info
 
@Ultradark Like I said, $(1-x)^{n/2}=x^n$ is equivalent to $1-x=x^2$ for any positive integer $n$ (so long as 0<x<1 anyways)
In which case $x=1/\phi$ is the relevant root. Hence that'll be a root regardless of $n$
 
I had to show that the function space was a topology, and that the function that the function space was built around would always be continuous.
 
The trouble is that, when you take an nth root, you have to worry about the fact that $x^n=1$ can have more than one solution
 
@CaptainAmerica16 As a high school student you can read it, but bear in mind it is at the level of a third year undergraduate math course.
 
4:33 AM
and I'm sitting here thinking "There's something I'm missing. It can't be that easy."
 
In particular, when $n$ is even you'll also have $-1$ as a solution. Hence when $n/2$ is even---as n=80000 is---you'll also have the possibility that 1-x=-x^2
This doesn't have a real solution, but it does have complex solutions
 
@Semiclassical I didn't know you like to use ---
 
occasionally, yeah
that or semicolons
 
I have never used and will never use ---
Same thing goes for internet on mobile phone, lol
 
@JasperLoy Just wondering: What about the book makes it so difficult. I'm only on the first chapter, so of course, I haven't had trouble so far. (I'm asking out of genuine curiosity, not cockiness.)
 
4:38 AM
@CaptainAmerica16 Well, many of the concepts may not make sense to you if you have not been exposed to some undergraduate math already, so you may think you understand the material when you really don't. But technically, other than informal logic, there are no formal prerequisites.
 
Some calculus: The function $x^n$, when $n$ is a positive integer, is an increasing function for any $0<x<1$, and as such $(1-x)^n$ is a decreasing function on $0<x<1$
 
@JasperLoy I get it. Worrying, but not discouraging. I shall push onward!
 
Consequently, any function of the form $f(x)=x^a-(1-x)^b$ is increasing on $0<x<1$ for any positive integers $a,b$
and f(0)=-1, f(1)=1
 
@CaptainAmerica16 I do know of several users on this site who don't get the math but think they do, but I am not referring to you! =)
 
Consequently f(x) has exactly one zero on 0<x<1
 
4:41 AM
@CaptainAmerica16 You can always skip parts you don't understand and come back to them later on, or post a question about your doubts on the site.
 
Actually, I can weaken that to $a,b>1$
 
I am now watching a movie, Adoration, about two mothers who are childhood friends and fall in love with each other's son, lol.
 
that seems...awkward
 
That is like wtf.
 
@JasperLoy I'll do that. I want to learn as much as I can. Thanks for the advice, now I'll be prepared if I get stuck :)
@JasperLoy I think I've. Matt Smith is in it I think. I'm not allowed to watch it.
 
4:44 AM
i mean, i don't want to say that's out-and-out "bad", so long as it's about consenting adults
 
*I think I've heard of that movie
 
but still....awkward
 
@CaptainAmerica16 Oh yeah, maybe there are some sex scenes in it, but nothing too explicit really. No, I don't think he is in it...
 
That might make for a good comedy
But, it's probably played more straight, for drama, right?
 
@JasperLoy Eh, I luv Matt Smith, but that sounds grody. I'm waiting for Captain Marvel!!!!!
 
4:47 AM
@CaptainAmerica16 I am sick of all the Marvel Cinematic Universe movies actually, too many of them, lol
 
having looked at the wikipedia page...awkward seems like a good summary of it
that and draaaama
 
@Semiclassical Yes, and in the case of non-adults, it's illegal but doesn't mean it's immoral. =)
 
@JasperLoy I might be thinking of the wrong movie then. If I get sick of Marvel, I watch DC. If I get sick of DC, I watch Marvel. I never get sick of either though, so that's basically all I watch. Well, that and Monk.
 
@CaptainAmerica16 Well, I love Matt Damon movies. Especially the Bourne series and Good Will Hunting.
 
@JasperLoy relationships are too complicated for me to have strong opinions about their 'morality' absent further context
 
4:50 AM
@JasperLoy I've actually never seen Good Will Hunting.
 
for instance, I'd have much different feelings were we talking about the relationship between a professor and one of their students
 
I actually think that the appeal of the Marvel movies is that there are so many of them, at this point.
 
The best Matt Damon film is The Talented Mr. Ripley.
 
superman spiderman batman antman lol
@Aubyn I like that one too.
 
first and third are DC, second and fourth are Marvel
 
4:51 AM
Like, people have watched so much of Tony Stark that they now care about him as though he were a real person they know.
 
@JasperLoy lol, most likely. I'm vaguely aware of the flaws, but I choose to ignore it over the fact that I'm going to own them all one day.
 
Marvel could play
 
It's funny to me that the Marvel movies have been so much better received than the DC ones
 
@Rithaniel I don't like his moustache, lol
 
@JasperLoy He made some really good films. The Informant is probably the least well known, but it's also really good. I finished the film without realising it was him lol.
 
4:53 AM
Well, that's a good reason to dislike someone, can't fault you there.
 
@Aubyn He even acted in The Great Wall with some Chinese actors, lol
 
I really liked S-dog millionaire
 
@Ultradark Yeah, story is cliche, but still nice.
 
Omg, It's almost 1. I have so much homework ;-;. Looks like I won't sleep until around 2:30. I did it for the math tho.
 
(I suspect that DC was perceived as pandering, where-as Marvel is perceived as earnest. Though, that is entirely speculation on my part, and colored by my own knowledge of the companies outside the movies themselves)
 
4:56 AM
@JasperLoy That's crazy. Didn't know that. I really like his films and tried to keep up, but it's hard!
 
I also like the Twilight series, but I only watched the first 3. =)
 
I've seen arguments made that it goes right back to the first DC Universe film, Man of Steel, and what it did with Superman
 
I never read the Twilight series
 
aka made him angsty/reluctant to use his powers when that's sorta the opposite of what Superman is supposed to represent
and as such, it put them in a corner when they got to the Batman vs. Superman movie
 
And for Harry Potter, I gave up after the first 4 movies.
 
4:57 AM
Actually, I thought Man of Steel was fine. Not a great movie, not faithful to Superman as he exists in the comics, but okay as a movie.
 
But I did watch all 24 Eon Productions James Bond movies!
 
I think there's two questions: how well it works as a movie, and how well it works as a starting point for the DC universe
 
My brother read every Harry Potter book at least 8 times for some reason
2
 
Also, yeah, I was a kid when the Harry Potter books were coming out, so I got into those. What Warner Bros did with the movies is part of why I distrust them as a company.
 
and my cousin cried when dumbledore died
 
5:00 AM
As a starting point? It's definitely not a starting point. It's good as a self contained unit, though.
 
maybe so. but that's what they had to work with when it came to the DC Universe
 
True enough
 
compare that to the original Iron Man film, which was both very good and a good starting point
 
This is a nice break from talking about math
 
Apparently the graph theory problem in Good Will Hunting isn't hard (not that I know).
 
5:03 AM
I agree. The original Ironman has a lot of poor plot points, but excelled in that was a very good origin story. As an extension, it could serve as an origin story for the entire Marvel universe.
 
man of steel sucks and so do most snyder movies
 
Oh yeah, that graph theory problem was hilarious.
 
I remember one time everybody was talking about like philosophy for the longest time and then mercio came in and was like it was so funny
oh isn't that graph theory problem like considered really easy
 
the good will hunting problem is something a elementary school student might accidentally have solved while doodling
 
12
Q: Proof Involving a Problem from "Good Will Hunting"

Jacob KoffI don't know if any of you have seen the movie "Good Will Hunting" but there is a particular mathematics problem in the movie that is of interest to be. One of the problems used in the movie is "Draw all homeomorphically irreducible trees of size $n = 10$." I've been able to draw all ten valid ...

 
5:07 AM
homeomorphically irreducible trees of size n=10
 
Drawing...
 
That's crazy! Maths in movies is weird; there was a recent one where a genius kid calculates the Gaussian integral and then solves Birch and Swinnerton-Dyer conjecture next or something.
It's called 'Gifted'.
 
gotta love hollywood math
 
I want to see a movie about Galois
 
Can anyone do me a goodwill by validating that $a \to (b \land c) \equiv (a\to b) \land (a \to c)$?
 
5:18 AM
i feel like biopics about historical math guys are usually kinda bad
 
I can't believe he solved a 350 yr old problem in his teens
 
the ramanujan movie was deeply mediocre and the turing movie was weirdly paced and struck me as kind of tone deaf to his actual history
 
@EricSilva yeah
 
I would want to believe it's true but somehow when doing truth tables I always get it wrong somewhere ...
alright thanks
 
I don't mind bad depictions of math in movies, really
but i do mind bad depictions of mathematicians as people
 
5:20 AM
@Semiclassical was that a thumb-up to me?
 
oh damn :/
 
Proof, A Beautiful Mind, Pi, An Invisible Sign, Gifted... all have characters with a mental illness. I believe A Beautiful Mind is based on a true story, but the rest aren't.
 
pi isn’t even really a math movie
 
3 mins ago, by Prashin Jeevaganth
Can anyone do me a goodwill by validating that $a \to (b \land c) \equiv (a\to b) \land (a \to c)$?
theorem imp_and_distrib {α} : (α → b ∧ c) ↔ (α → b) ∧ (α → c) :=
⟨λ h, ⟨λ ha, (h ha).left, λ ha, (h ha).right⟩,
 λ h ha, ⟨h.left ha, h.right ha⟩⟩
 
5:22 AM
lol
 
@PrashinJeevaganth ^ there you go
 
Woah, this is by far the greatest life hack I have seen, all the existing equivalences
 
@EricSilva True, I suppose. Just some guy obsessed with patterns/numbers.
 
can that solve any problem
 
@LeakyNun Huge thanks man, I'm getting addicted to this chat group already
 
5:23 AM
you're speaking to an addict
 
I wanna be part of this math community too ... but well I'm not apt enough
 
Me neither
 
I'm a year 1 CS major and I'm struggling with almost all the modules, I'm not even procrastinating
 
wanna start our own average math community
 
I just discovered this chat group like yesterday
@Ultradark we should aim to get value-added, not group all the average people together XD
 
5:25 AM
@EricSilva I read that in the Turing film they had to throw extra doses of social anxiety and awkwardness at the character (whereas in reality Turing was a very social guy).
 
he also wasn’t mega into crosswords like the movie would have you believe
i mean it’s really i think a problem w just how biopics kinda are, you have to fictionalize a lot to get a good movie, peoples lives just aren’t good film plots, and it’s hard to strike the balance between honest and good filmmaking
especially w math nerds cause unfortunately the things that would excite us are a snoozefest to look at
 
True.
 
Is it possible that everyone here is just a robot
 
5:42 AM
Only a robot would say that
 
Does anyone know what this is talking about regarding propositional logic?
 
@PrashinJeevaganth pretty sure i'm the only one in this room who knows lean
and it just says $\neg b \to \neg (a \land b)$
$\neg$ means negation
 
6:02 AM
Where does the a appear from?
haha nvm, I think I will just look up the biconditional ones for logical equivalences ... the rest seems to be very deep into this
 
nowhere
 
6:20 AM
@Ultradark I'm 75% sure I'm a robot. Anyone else?
 
6:31 AM
does anyone have idea how to do this problem?
 
6:44 AM
@Ninjahatori maybe you should be more familiar with analysis before doing fancy stuff
such as Banach space
which step are you stuck on?
 
7:02 AM
I know that normed linear space is banach space iff iff every absolutely convergent
series is convergent in E. So basically we know norm so we take summation norm of (x1,x2)_n and then summation (x1,x2) converges. where norm is given by defining the operation .
@LeakyNun
 
I don't think thinking about series is a good idea
 
Why is this case so? Is it possible to show without series?
 
series is obviously more complicated than sequences...
 
so basically we we want to show every cauchy sequence converge in D because norm is already given to space?
@LeakyNun
 
yes, naturally
 
7:14 AM
@LeakyNun I'm trying to power through my last calculus assignment. My teacher uses a million different representations for function composition. (fg)(x) just means f(g(x)), right?
 
depends...
context?
 
@LeakyNun $f(x) = 4x+16$ $g(x) = $2x^2$ find (fg)(x)
I didn't even do the mathjax right
 
@LeakyNun I know for real how to show but what about if we have tuple (x1,x2) can you please show me how to do this?
 
how to do what? @Ninjahatori
@CaptainAmerica16 that's... troublesome
 
cauchy sequnece converges?
 
7:17 AM
closed as unclear :P
 
@LeakyNun :(
@LeakyNun I'll just multiply and compose the functions and then see which answer fits the given choices. I'm too sleepy for this.
 
@CaptainAmerica16 that's the correct approach
@Ninjahatori show that a sequence is cauchy iff each component is cauchy
and that a sequence converges to (L1, L2) iff the left component converges to L1 and the right component converges to L2
 
@LeakyNun Looks like it wanted me to multiply.
 
I see
 
Ok I got it but how to show map x goes (x,0) is isometry?
 
7:30 AM
maybe you should start thinking about it
 
A proper map between topological spaces is a continuous map such that the preimage of a compact set is compact. Does one mean quasi-compact, or quasi-compact Hausdorff?
 
how the d((x,0),(y,0)) looke like ? d is norm function? @LeakyNun
 
@Ninjahatori What is the metric on the source and target?
Or what is the metric on the domain atleast.
 
norm function doesn't take two arguments
also, apply definitions
@user490981 quasi-compact
 
it is same as we defined for complexification in above problem?
 
7:37 AM
@LeakyNun Excellent, thanks
@Ninjahatori If that was in response to me, do you mean above in the textbook?
 
yes @LeakyNun
 
I am now more confused, because I am not LeakyNun and you said yes
 
ohh sorry @user490981
 
So 1) How do you get the metric from the norm, 2) What is an isometry, 3) What is the metric on $\mathfrak{X}$?
 
@LeakyNun @user490981 can you please show me why x to (x,0) is isometry ? problem is given above in this chat?
 
7:43 AM
Answer my three questions?
 
isometry is distance preserving map or norm preserving map. X is real banach space so it has standard euclidian metric and for first we have define complexification norm.
@user490981
 
If you write the definition of an isometry mathematically, and then test it out, you'll find yourself quite happy I am sure
 
fine thank you sir
@LeakyNun @user490981
 
8:28 AM
@TedShifrin, @mercio: I'm sorry for taking up so much of your time and effort yesterday. I was very stressed and started asking questions without thinking first. (Referring to the part where I was to show the results for $E=\ell^p$ and $E=c_0$.) I'll try to refrain from doing that in the future, and if having a prolonged conversation preferably starting a separate chat room for that chat as not to take up the entire chat here. I'm however of course very thankful for your help.
 
8:42 AM
Update on the progress:
ok so...
Without twisting the surrounding environment a lot, a $\mathfrak{c}+1$ level zoom will really only give you that given number surrounded by a sea of infinitesimals
There cannot be any other real numbers nearby because any of them will be at least a real number apart from the number in the center of the window, which is not infinitestimal
So yes, you can do a continuum level zoom, its just not interesting until you mark out certain family of infinitesimals (which will follow more or less the same pattern due to the way the surreals are constructed)
Therefore, for any zoom level $m < \mathfrak{c}$ you will get something like the first picture
once you hit $\mathfrak{c}$, the number at the center is the only one you will see
Now to figure a projective geometry that can project the two infinitely far ends in the 3rd picture to points at infinity, so that the relation between the rationals and the irrationals can be shown by clearly
 
9:47 AM
@Secret: Maybe you could create a separate chat room for this. It would improve readability.
 

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Discussion related to the use of algorithms and programs to vi...
Done
The stuff is finally coherent enough to contain in a small room
 

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