user19161
8:07 PM
@JonasTeuwen Wait, I don't understand that statement.

Don't worry bro, me neither.
Actually I do.
NL is the home or one of the first countries with 'gay marriage', 'euthanasia', 'sex change surgery'.

user19161
Don't worry bro. Just don't get suspended again.

So it would be perfect if the Queen became a man, married to one and then went for euthanasia.

@JasonBourne : +1 from my side

user19161

8:12 PM
@JasonBourne : I am planning to change it soon :P

user19161
@Theorem To your real name? I change mine all the time until most people don't know who I am anymore.

Hi all

@JasonBourne : I had my real name so i am bored of it as well , may be some other name .
@OldJohn : Hi , had dinner ? :)

user19161
@Theorem Yeah we get bored, but after we change it we regret it, LOL.

user19161
@OldJohn No recent answers from you I see.

8:14 PM
@Theorem Yep - just finishing it off with an espresso
@JasonBourne No - too busy answering my own questions :)

@OldJohn : time to do some maths after espresso :)

user19161
@OldJohn Yes, you are probably secretly working on the remaining millennium problems.

@JasonBourne No - I know my limitations, and only work on things I have a hope of solving :)

user19161
@OldJohn Anyway, I predict your next photo you will face the left instead of the right, LOL.

anyone interested in solving P vs NP problem ?

8:17 PM
@JasonBourne Or I might face away from the user ;/

user19161
@theorem Guess what, someone downvoted that answer without commenting...

@OldJohn Hello. Sir.

@JonasTeuwen Hi! - how are things?

Pretty messed up! But nothing much different so I guess: Good! How about you?

@JasonBourne : There are some nuts :P

user19161
8:21 PM
@Theorem I did not want to write it as there exists x such that there exists y such that ... but to give a slightly different way of looking at it. Probably a nutcase then.

@JasonBourne : Its sad that very often people just like to downvote for no reason and i specially like calling them nuts :P

user19161
@Theorem They might downvote for the above reason, but that shows they have not reached that mathematical maturity to see beyond the immediate implications. =)))

@JasonBourne : Even then i don't see a reason to downvote , if they don't understand they are free to ask or argue why its wrong . simply down voting shows that they are actually nuts

@JasonBourne I downvoted just to give chat something to talk about.
(kidding, of course)

@JasonBourne I would not downvote for this reason yet. But I think with a few more links to the question here in chat, I might have

8:27 PM
Its not that i know lots of answers , but even when i know the answer i give up writing up the answer because it takes me hours and hours to write the answer , i don't know how to improve my latex typing speed .

user19161
Hey guys you know what now? My rep is not a multiple of 5. That makes me sad. I will need to downvote some answers now... However I have run out of votes for today, so I will do it tmr.

Practice.

As was his style, Kepler could not resist sharing his unique inter-
pretation of this mathematical observation. He assigned genders to the
solids and used duality to indicate sexual compatibility. The cube and
the dodecahedron (both dominant primaries) were male and contained the
female octahedron and icosahedron (secondaries). The tetrahedron was a
hermaphrodite because it contained itself. The faces and vertices were the
sexual characteristics because that was where the solids met.
> THE TETRAHEDRON WAS A HERMAPHRODITE!

Always knew that those tetrahedrons had something funny going on.

@EdGorcenski =D

8:30 PM
@JasonBourne the reason being, even though the answer is correct, I don't really find it interesting enough that it warrants advertising on chat

user19161
@Tobias Ah, so you were the one who downvoted it? It is alright if so. =)

No, as I said, it would have taken a few more links to the answer

How can you parametrize a screw?

and even then, I might not, depending on my general mood

@hhh conical helix?

8:32 PM
@OrangeHarvester Something like here?

user19161
@Tobias Oh well, I guess I am a rep whore then. =)

@hhh you already have a solution I gues?

@OrangeHarvester Not yet, it is not a screw

user19161
Who is the one doing all the starring?

@hhh What do you mean when you say you are looking for a screw?

8:34 PM
@JasonBourne starring went crazy last night - maybe it is the same person (cannot be me, as it was mostly my posts starred last night)

@hhh Is the image provided by nathan a close approximation?

user19161
@OldJohn Ah, I think the person who did the starring might have done the downvoting and maybe also the flagging. =)

myword.info/images/sm_screw_1g.gif <--- this is a screw that I am trying to plot

@OldJohn Jack the Starrer.

(or I believe when I can do it, I can do my original problem -- I want to get conical screw)

8:35 PM
@OrangeHarvester darned starrers - should be banned
6

@OrangeHarvester It misses the elevation of the fridge

@hhh That is a pretty tough thing to parametrize. I am assuming you are not hoping to parametrize the head itself?

user19161
@tobias I usually don't advertise my posts in chat. But sometimes I feel sad that a post is still at 0 after very long, so I do that now and then. Also, all my answers are trivial, so you don't need to bother looking at them if you want something non-trivial. =)

@OrangeHarvester err I want a cone that has a groove/fridge -- i.e. a groove spins around the surface from top to bottom where ball can roll.
If you release a magnetic ball on the top of the cone, it will go along the groove -- this is what I am trying to parametrize

@hhh If you are trying to solve the case by hand, I am not sure why would you need a protrusion for analyzing that.

8:39 PM
If I am able to find a way to get Screw-shape, then I am pretty sure how to do other shapes

The ball follows a conical helix and that is the end of it.

user19161
@OldJohn Careful, they might flag you for that. =)

@JasonBourne I consider it the responsibility of mods to prevent flag abuse, not mine.

hello

8:44 PM
how do I know you?

user19161
@OrangeHarvester You know who Tessa is?

right i do not remember you
i apologise
anyway could i get some help

@hhh What you can do is
1. Project a function like $y=|a-x|$ on a conical helix. And the project that helix onto a cone.

Prove the following: if |G| > 1 is not prime, then G has a proper subgroup

8:47 PM

I did a really good proof of if it is prime then it only has the identity and the group itself.
but Im not sure on this one

right, this one is slightly more tricky
since it has size > 1 take a non-identity element
what can you say about the subgroup generated by that element?

no idea. group theory is scaring me at this moment in time.

Can you use Cauchy's Theorem?

well, what happens if this element generates a proper subgroupo?
@EdGorcenski Cauchy is way overkill for this

8:49 PM
not heard of cauchys theorem as of yet. we were doing lagrange at the time.

the elementary solution is instructive

user19161
It's scary huh, people starring and flagging our posts and not confessing. Could be a serial killer.

Lagrange's theorem is related.

does it make a cyclic subgroup

But yes, you don't need Cauchy's theorem

8:50 PM
@TessaDangerBamkin right. What can we say if this subgroup is proper (recall what it is we want to show)?

im a girl and i do maths yaay
2

user19161
The order of the subgroup divides the order of the group.

sorry. my husband just jumped on to bug me.

I claim that if this subgroup is proper, we are done. Why is this?

okay so if the subgroup is proepr then the order divides the order of the group

8:51 PM
don't use Lagrange yet

we wanted to show that the group had a proper (and non-trivial) subgroup
so if this subgroup we have found is proper then...?

then it is not the identity or the group itself

compare to what we wanted to show

user19161
Hey @tessa now I remember talking to you before, under another username...

8:53 PM
are we all using different usernames?!

@robjohn Do you know something about distributions on hyperbolic measures? For instance $\partial_{x_j} \partial_{x_i} r^{-1}$ where $r$ is some hyperbolic thingie in $x_i$.

right so I want to show that G has a proper subgroup and if I assign an element to be this subgroup then i have found it? Im really confused right now. I do heavily apologise, I feel it must be frustrating for you pros

@TessaDangerBamkin well, if the subgroup we have found is proper, then we are done, so we can assume it is not and proceed from there
This reduces to showing the claim for cyclic groups

user19161
Whoa I find that there are more downvotes these few days compared to last year.

user19161
See how fast the questions get downvoted?

8:56 PM
okay and what is this claim? yes i need babying

the claim was that the group has a proper non-trivial subgroup

tobias im getting confused slightly treat me like an idiot for a sec and explain it like you would to that person
maybe just write the proof you'd do and I'll try and understand because I don thk im going to be able to get it from my head right now

user19161
Yeah I am getting confused too, LOL

@TessaDangerBamkin The outline of the proof goes something like this:

i hope thats not sarcasm Jason

9:02 PM
hi

Pick an element x in G that is not the identity. Make a subgroup out of it. Either that subgroup is proper, or it is not. If the subgroup is proper, then we're done! If it is not proper, then it must be the entire group. If it is the entire group, then the element has some certain given properties.

user19161
Hey @mariano I just realised you have cast so few votes, LOL

user19161
@EdGorcenski Well done.

Then, if x has those properties, show that the order of G has properties that contradict your hypothesis (in other words, if <x> is a non-proper subgroup, the order of x relates to the order of G in such a way that means that |G| must be prime)

@JasonBourne Naah, we're both too lazy to get married ;)

9:04 PM
@TessaDangerBamkin Now, using that sketch, see how Tobias's hints lead you along that path :)

user19161
@Rachel Oh. OK, as long as you are happy! Marriage is just a formality.

thanks ed
I shall try my best

@JasonBourne Surprised you remembered me from that :)

@EdGorcenski no, that is not quite right

user19161
@TessaDangerBamkin Do you get it now? If not I can elaborate.

9:05 PM
there are groups not of prime order with some element generating the entire group

elaborate away. the more help the better! :D

user19161
@Rachel I am Jasper by the way, and I have deleted my Eng account!

@JasonBourne Oh I remember you then :)

If x generates a group of composite order and d is any proper divisor of said order not equal to 1, then x^d generates a proper nontrivial subgroup.

Well, then ignore my parenthetical point ;)

user19161
9:06 PM
The great anon has spoken.

Beyond the horizon of the place we lived when we were young

The ocean?

user19161
@ilya What are you saying?

and in fact its the answer

awesome

user19161
9:08 PM
Ah, that was a nice refresher for my group theory.

In a world of magnets and miracles
Our thoughts strayed constantly and without boundary

@JasonBourne : which / what ?

user19161
@ilya Did you just take the wrong drugs?

dont worry I'll be back to bug you
this course is too abstract right now for my little brain

@JasonBourne Baby, did you forget to take your meds?

user19161
9:09 PM
@Theorem Well, how a group of composite order has a proper nontrivial subgroup.

user19161
@Ilya Haha, I call you dear and you call me baby? Your wife will be suspicious!

@TessaDangerBamkin :most mathematicians are made , they are not born so it's same for everyone
@JasonBourne : interesting na :D

got thisproblem from another site: No group can be written as the union of two proper subgroups

@JasonBourne you don't change
good bye, you almost asked for that

user19161
@user58512 Not quite.

user19161
9:12 PM
@Ilya Bye! See you!

good night Volks :)

user19161
@anon I now have a feeling that you look like the person in the picture.

whats the picture from anon?

Hi

9:19 PM
A girl, maths, and bad spelling. Does not sound so nice 8-(.

@user58512 Suppose $G=H\cup K$, pick $x\in H\setminus K$ and $y\in K\setminus H$. So where is $xy$?

I don't know, it could be in either

$xy\in H\iff y\in x^{-1}H=H$ and $xy\in K\iff x\in Ky^{-1}=K$

user19161
@anon That also shows the flaw in the statement as given.

Eh?

user19161
9:23 PM
Oh wait, I misread the statement.

user19161
Ignore my nonsense.

Anyway this shows in general that $(H\setminus K)(K\setminus H)\cap(H\cup K)=\varnothing$.

@JonasTeuwen not really. Sorry.

@user58512 : one of the easiest arguments can be using the order of the group .

user19161
@rob I have decide not to keep my rep at a multiple of 5 anymore, it's too hard with all the downvotes these days...

9:25 PM
@Theorem how would you use the order for that?

@JasonBourne you've been getting a lot of downvotes?

@JasonBourne Everytime I see your rep not a multiple of 5 I'll make sure to downvote you so that it is.
Consider it my civic responsibility.

user19161
@robjohn Not really, but if it is not a multiple of 5 I would need to find three answers to downvote which can be quite hard, LOL.

user19161
@EdGorcenski LOL

Last time I asked in chat for a precise number of downvotes (to obtain 31415) everyone and their dog jumped on the bandwagon.

9:27 PM
@anon LOL

user19161
@anon What is special about that number?

It's exactly 10000 times pi.

exactly?

(that feeling was everyone in the room twitching)

user19161
Truncated.

user19161
9:28 PM
Not even rounded. or it will be 6 and not 5.

Indeed.

user19161
I wonder if I will ever know the identity of the great anon...

user19161
Wow, interesting that crystal = glass = glasses = 8.

9:44 PM
@Tobias : looks like i have to spend some more time thinking about it .
@Tobias : I am not sure if it works , but lets see

user19161
I am kind of sick of the answers that go as XXX pointed out or a YYY pointed out. It's just noise to me. Yes, I know about the acknowledging others part but that's really not necessary to me. We are not stealing people's research here, LOL

10:02 PM
Give credit where credit is due.
2

user19161
Even for 1+1=2?

user19161
So now my answer goes like this: As Jonas pointed out, 1+1=2, but he only commented so I am typing this as an answer.

user19161
I would just prefer to see an answer that says: 1+1=2. QED.

Precisely, that is what 'is due' is supposed to say.
It means 'someone in his right conscious mind should do the right thing'.

user19161
10:22 PM
Hey guys, I actually think that some downvotes could be accidental.

user19161
Many times, I wanted to click on upvote but because the page moved I clicked on the downvote instead.

user19161
This happens especially on math when the tex takes long to get converted.

10:50 PM
Hi @WillJagy

Howdy

I was about to post the following, but it feels not enough for a full question.
So I'd like to post it here:
How does the concept of factoring natural numbers carry over to complex natural numbers?
with regard to arithmetic functions I mean...

@draks..., prime numbers equal to 1 mod 4 split and ones equal to 3 remain prime

Yes I know

10:54 PM

I thought about ..wait ia second

who is wolfgang muckenheim, and why does he tick ppl off so?

user19161
@draks... Do you mean the Gaussian integers?

something like this $g(n) = \sum_{d|n}f(d).\;$
So $d$ could be a compex number then right?

i would think it would have to be as $\Bbb N[i]$ is not closed under multiplication

10:56 PM
@draks..., have you tried defining a mobius function for it?

how did you guess that?

user19161
Hey @math

Hey @JasonBourne

user19161
@math101 So have you thought about the exercise I gave you?

@DavidWheeler probably because he refuses to listen to logical arguments and just bangs on and on about his own crazy theories?

10:59 PM
@JasonBourne Not at all. I just came back from work :)

user19161
OK guys, now that I have cast exactly 200 downvotes on main and 20 downvotes on meta I declare that I won't cast any more downvotes on SE.

@DavidWheeler who or what is ppl?

user19161
@math101 Oh, alright.

Ya gonna catch something to eat and head straight first into math

@draks... ppl = abbreviation for "people"

11:00 PM
@JasonBourne should we star this to have some evidence when you ever do it again?

user19161
@draks... Haha, I always change my mind!

@DavidWheeler, Wolfgang Mueckenheim: math.stackexchange.com/users/29503/wolfgang-mueckenheim

@OldJohn what kind of crazy theories?

user19161

@DavidWheeler he has some very non-standard ideas about real numbers and countability - I think he refuses to accept Cantor's diagonal argument proving the reals are uncountable, for instance
I followed some of his "arguments" out of amusement - before they were all deleted

user19161
11:03 PM
@OldJohn Is he a genius or a crank?

@DavidWheeler how would this affect a complex variant of the möbius function?

why is "cantor was wrong" so common?

@JasonBourne I think he is a well-known crank - although he is a professor of something like physics at some university

I understand "godel was wrong".. but not that

user19161
@OldJohn Ah, I don't really trust someone with the title of "professor" even in math. I have met enough professors who talk crap in classes.

11:04 PM
I really don't know - I read Cantors's book on the founding of the theory of transfinite numbers when I was at school - and thought it was wonderful

well i've read some very interesting articles about what cantor's argument might mean if we adopt a non-standard model of ZF

@JasonBourne me too

user19161
When I attend these prof's lectures, I wonder how they got their PhDs.

are there any prof around yet?

user19161
11:05 PM
Sure, teaching is not the same as research, but some profs really don't care about teaching at all!

@math101 work?

@user58512 Hey com' on. we had a good start...

@draks..., hi

user19161
11:06 PM
@OldJohn From my dreamland too.

@user58512 yeah hi

from what little i've seen, he ruffles people up by being argumentative
sometimes to the point that peoples' replies seem to be more ad hominem than "on-topic"

@OldJohn as long as we don't get another M....o K..o, who cares?

@OldJohn One of the more notable mathematical cranks. It’s appalling that he holds an academic position.

@BrianM.Scott Yes -I thought he was quite good for entertainment for a while - once you get past his argumentative style.
But I got bored of his stuff after a few days :)

user19161
11:10 PM
@DavidWheeler I never met him on main, but he does not really post that much either.

@draks... MK seems to have gone rather quiet recently, I think

@OldJohn I’ve seen it all over: here, de.sci.mathematik, sci.math, at least one other web-based forum, and at least one paper somewhere. And yes, by now it’s pretty boring! (And I get a kick out of crackpots if they’re at all interesting.)

user19161
What was he suspended for?

@OldJohn maybe he's got what he was looking for...I hope!

11:12 PM
i'm interested in "non-standard mathematics"...i'm not entirely prepared to embrace ZF set theory as true...just "convenient".

@BrianM.Scott I am glad he didn't discover this chatroom, then!

I wonder the same thing

@DavidWheeler, can you tell me about it?

@JasonBourne He does not believe in infinity.

user19161
@robjohn There can be infinity when you believe.

11:15 PM
believing in infinity is the only way. You will never encounter it in real life...
despite in [human's stupidity](http://quoteinvestigator.com/2010/05/04/universe-einstein/)

@OrangeHarvester I think it is close to what he believes, if not exactly. It is hard to tell.

non-standard

@robjohn okay.

11:18 PM
oh...well one can insist that all sets be finite, or countable, or hereditary, for example

oh right

@OrangeHarvester to the ultrafinite people, even big does not exist.

is that the cumulative heierarchy

that's one kind of hereditary set list, yes

user19161
11:19 PM
@draks... Well, pasting the link of a user profile, question or answer, youtube or wikipedia autoexpands in chat if there is nothing else on the same line, but I do this only sparingly sometimes to exaggerate something as some people don't like too much expansion in this chat, so to avoid it just type something else on the line.

ok here it goes:
Is there a complex variant of Möbius' function?
http://math.stackexchange.com/q/289344/19341

@robjohn yes, I am familiar with finitism and such. I must confess even I have wondered some years ago as to how can be talk about numbers which may not even exist.

As of tomorrow there is 'Professor' on my office door... but only temporarily as the occupant is not occupying it 8-).

You moved back?

This is even a bigger one than my previous one.
With a sofa, (...)...

11:28 PM
Lucky profanity.

@JonasTeuwen ooh... a coffee machine

@draks..., maybe we need to factor into ideals rather than gaussian primes, that would fix the trouble with arbitrary choice of units
i.e. the arithmetic functions need to be defined on ideals

@user58512 ok sounds good
<back in a minute>

11:53 PM
thx so far everybody, gotta go, good nite...

user19161
@draks... See you in your dreams.

@JasonBourne W...what??

user19161
@draks... Well, just a favourite line of mine I say to almost everyone.

I don't want my dreams to be blue...

user19161
What colour do you want?

11:55 PM
green yellow red

@draks... Booooring! Why not puce, mauve, beige, magenta, ... ? :-)

@BrianM.Scott I don't know what you are taking, but it's your choice...nice dreams to everybody!

@draks... G’night!

or even gamboge, or taupe or ...