« first day (2384 days earlier)      last day (2528 days later) » 
00:00 - 09:0009:00 - 10:0010:00 - 14:0014:00 - 16:0016:00 - 20:0020:00 - 00:00

Slereah
Slereah
4:00 PM
I plan to live forever
Shouldn't be too hard
Just gotta avoid dying
 
Balarka Sen
Balarka Sen
fite god
 
John Rennie
John Rennie
-6
Q: SCIENCE IS THE BEST BUT I HAVE QUESTIONS

J. Doewhat does this have to do with AIR PRESSURE PEOPLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!...

climate-science
 
user228700
Omg lol x'D
 
John Rennie
John Rennie
I love the way someone has attempted a rational reply in a comment :-)
 
user228700
"PEOPLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!" x'D
 
Balarka Sen
Balarka Sen
4:03 PM
stack exchange is the best but i got banned!!!1!!
 
user228700
@JohnRennie I bet it features a lot of Ogden Nash :-)
 
John Rennie
John Rennie
The Hippopotamus by Hilaire Belloc

I shoot the hippopotamus
With bullets made of platinum,
Beacause if I use leaden ones
His hide is sure to flatten 'em.
 
user228700
That's...nice :-)
 
user228700
Oooh, @JohnR: Did u see the thing about the abandoned ferris wheel?
 
John Rennie
John Rennie
A crusader's wife slipped from the garrison,
To have an affair with a Saracen,
She was not oversexed,
Nor jealous nor vexed,
She just wanted to make a comparison.
@Kaumudi.H Abandoned ferris wheel? No, what was that?
 
user228700
4:09 PM
 
user228700
...and a few lines of conversation following that.
 
John Rennie
John Rennie
Scary stuff - the ghost of communism
Probably the question asked most often is "Do one celled animals have orgasms?" The answer is yes, they have orgasms almost continually, which is why they don't mind living in pools of warm slime.

Dave Barry - Sex and the Single Amoeba: What every Teen Should Know.
 
Slereah
Slereah
Boooo the workers shall control the means of productiooon
 
John Rennie
John Rennie
Good grief, the new Hawkwind album is no. 2 on the BBC Radio 1 rock album chart.
 
ACuriousMind
ACuriousMind
4:25 PM
Who listens to radio, anyway?
 
Secret
Secret
> Recent evidence indicates that several Amoebozoa lineages undergo meiosis.

Orthologs of genes employed in meiosis of sexual eukaryotes have recently been identified in the Acanthamoeba genome. These genes included Spo11, Mre11, Rad50, Rad51, Rad52, Mnd1, Dmc1, Msh and Mlh.[51] This finding suggests that the ‘’Acanthamoeba‘’ are capable of some form of meiosis and may be able to undergo sexual reproduction.

The meiosis-specific recombinase, Dmc1, is required for efficient meiotic homologous recombination, and Dmc1 is expressed in Entamoeba histolytica.[52] The purified Dmc1 from E. histo…
Amoeba
An amoeba (/əˈmiːbə/; rarely spelled amœba, US English rarely spelled ameba; plural am(o)ebas or am(o)ebae /əˈmiːbiː/), often called amoeboid, is a type of cell or organism which has the ability to alter its shape, primarily by extending and retracting pseudopods. Amoebas do not form a single taxonomic group; instead, they are found in every major lineage of eukaryotic organisms. Amoeboid cells occur not only among the protozoa, but also in fungi, algae, and animals. Microbiologists often use the terms "amoeboid" and "amoeba" interchangeably for any organism that exhibits amoeboid movement. In...
Ok, I thought that guy is making some kind of sexual themed alternate theory on animal reproduction, turns out nature is stranger than you think
 
John Rennie
John Rennie
@ACuriousMind I listen to mostly (Internet) radio these days. I find it's a good way to hear about new bands that I wouldn't otherwise know about. Admittedly I get to listen to a lot of crap bands too :-)
For the record (no pun intended) the new Hawkwind album probably won't appeal to any but the die hard Hawkwind fan.
 
Sir Cumference
Sir Cumference
-7
A: Is the influence of gravity instantaneous?

dv1penguinIf the speed of gravity were equal to the speed of light, which most conventional astronomers believe, our solar system would have evolved in a completely different way. The speed of gravity is a critical physical fact that tells us why the theory of General Relativity is an absurd hypothesis i...

Love Rob Jeffries' response
 
Slereah
Slereah
"He didn't just make it up like Mr. Einstein would do."*
@AlbertEinstein what do you have to say for yourself
 
Secret
Secret
4:43 PM
> There are many einsteins, but only one is real
 
Slereah
Slereah
Also more importantly
If I do a GR book
what do I call it
I get the impression that GR books either have very short or very long titles
It's either "Gravitation" or "Exact solutions of the einstein field equations"
 
AccidentalFourierTransform
AccidentalFourierTransform
"GR", or "A complete treatise on gravitational phenomena, from differential geometry to cosmology, geodesic motion, black holes and causality - A new perspective - Volume I."
 
Slereah
Slereah
Pretty much
Just like old timey books
Galileo's own "The Discourses and Mathematical Demonstrations Relating to Two New Sciences"
 
AccidentalFourierTransform
AccidentalFourierTransform
I would have gone with "science, yo' - Galileo"
 
0celouvskyopoulo7
0celouvskyopoulo7
I would go with: The Mathematical Theory of Gravity
Well, maybe not
My hypothetical book doesn't really concern itself with gravity
How about just "Mathematical General Relativity"
 
Slereah
Slereah
4:58 PM
Yeah I'm gonna have it a bit more grounded in physics
 
0celouvskyopoulo7
0celouvskyopoulo7
Why?
 
Slereah
Slereah
I guess I could just call it "general relativity", but then there's a lot of books with that title
cuz I'm a physicist
 
0celouvskyopoulo7
0celouvskyopoulo7
GR is not a realistic physical theory though
 
Slereah
Slereah
Is it
it predicts a ball falling down
 
0celouvskyopoulo7
0celouvskyopoulo7
ok, btw
 
Slereah
Slereah
5:00 PM
pretty good prediction
 
0celouvskyopoulo7
0celouvskyopoulo7
that's the book with Sanchez in it
I think
 
Slereah
Slereah
nice
 
0celouvskyopoulo7
0celouvskyopoulo7
Actually no...
It has a Sanchez article in it
But not the usual one
 
Slereah
Slereah
What is the prediction of throwing a ball in GR anyway
I don't think Schwarzschild has a generic solution for geodesics
 
0celouvskyopoulo7
0celouvskyopoulo7
god, who knows
 
Slereah
Slereah
5:01 PM
Radial one is probably doable
 
0celouvskyopoulo7
0celouvskyopoulo7
@Slereah Radial for sure
General orbits are not analytically known
 
Sir Cumference
Sir Cumference
@Slereah Go for something more eye catching, like "10 wacky equations (solutions inside!)"
 
0celouvskyopoulo7
0celouvskyopoulo7
one approximates with Newton +$1/r^3$, then does some shit
 
Slereah
Slereah
I guess throwing a ball straight up has a solution
 
0celouvskyopoulo7
0celouvskyopoulo7
it's in every book
 
Slereah
Slereah
5:02 PM
Did anyone do that experiment
Throw a ball up
Look at the deviation from Newton's theory
 
Sha Vuklia
Sha Vuklia
Guys, is it possible to visualise why a field, whose curl is zero, must be the gradient of a scalar valued function? (I can prove this direction: $E=-\nabla V\implies \nabla\times E=0$), however, since the proof in the other direction involves advanced maths, I was hoping I could make this intuitive for myself. Is it that rotating vectors cannot represent a gradient? (if we're thinking of the steepness of hills, for instance)
 
Sir Cumference
Sir Cumference
@Slereah Thank me later
 
Secret
Secret
@ShaVuklia Think about if the vectors are gradients, it tells you which direction is uphill. Now think about what happens when you apply this logic to a swirling vector field
 
Sha Vuklia
Sha Vuklia
yea I was trying to visualise that
let me think (or draw)
 
Slereah
Slereah
In the meanwhile I have to do my homework
Terrible
 
Sha Vuklia
Sha Vuklia
5:08 PM
@Secret wouldn't we get something that spirals upwards?
 
Secret
Secret
@ShaVuklia No, you will get something that look like a penrose stairs after you completed a cycle around the region of nonzero curl
 
Sha Vuklia
Sha Vuklia
ohhhhh, wow
 
Secret
Secret
which means the start and end point will have two values for the potential (the height of the hill) and we normally don't use multivalued potentials
 
Sha Vuklia
Sha Vuklia
did not think of that at all
wow, I had no idea the answer was that simple
 
Secret
Secret
and this is why any nonzero curl vector field is not a gradient, because if it were so, we would already have a perpetual motion machine by placing a ball bearing in such potential
as it will, as you have noticed it forms a spiral, it rolls downhill forever, releasing unbounded amount of kinetic energy
 
Sha Vuklia
Sha Vuklia
5:11 PM
wow, that makes sooo much sense.
damn, I did not expect such a satisfactory answer
thanks
 
Secret
Secret
(Unrelated: Too bad physical infinities don't exists, (except possibly the gravitational singularity in black holes), otherwise economics would be much simpler)
Pictures are often good at intuition, but it only really helps if you have a solid understanding of the subject in question
and there are concepts too abstract to be captured by pictures without distortion, thus be aware of different learning methods
 
Sha Vuklia
Sha Vuklia
yea true
I must say tho; since I've been doing physics the past two weeks, I've really had to resort to my intuition many, many times. I think mathematicians have the luxury of being able to turn of their intuition and simply work from definitions and theorems.
 
Sir Cumference
Sir Cumference
Question: is chemistry just physics in disguise?
 
Secret
Secret
Chemistry=mostly electron shell physics, plus some rules of thumb
 
Sir Cumference
Sir Cumference
Like, people complain that there's an astronomy SE (saying that astronomy is just physics), but no one says anything about chem SE
 
0celouvskyopoulo7
0celouvskyopoulo7
5:16 PM
@SirCumference no
chemistry is a bunch of rules of thumb
 
Secret
Secret
The thing is, while yes it is fundamentally electron shell quantum physics and statistics, the methods and thinking process (such as the emphasis in an array of representations and diagrams to aid in the thinking, and the heuristic guidelines) makes chemistry so distinct it can no longer be considered completely a subdomain of physics
 
Sir Cumference
Sir Cumference
Hmm, so where do you draw the line between Chem and Physics?
 
0celouvskyopoulo7
0celouvskyopoulo7
Please don't call it Chem.
 
Phase
Phase
Honestly, I hate chemistry. A lot. But I get annoyed when people say it's just physics. If it were physics, then physics would have to: 1) be complete and 2) allow the results from chemistry. I feel like analytically solving the schrodinger equations for heavy metal atoms would be a huge waste of time and at this time impossible.
 
0celouvskyopoulo7
0celouvskyopoulo7
It's Chemistry.
 
Sir Cumference
Sir Cumference
5:19 PM
@0celouvskyopoulo7 You don't say "astro"?
 
0celouvskyopoulo7
0celouvskyopoulo7
No.
I say "trash."
 
Sir Cumference
Sir Cumference
I realize now that sounds a bit nerdy...
 
Phase
Phase
@0celouvskyopoulo7 Math or Maths
 
Cows
Cows
@0celouvskyopoulo7 on page 43. . . working through defs and concepts . Got back on the horse this morning. "(It is left to the reader to
understand how to make the set of equivalence classes into a vector space.)"
 
0celouvskyopoulo7
0celouvskyopoulo7
Math is fine.
 
Phase
Phase
5:20 PM
Oh
Well, die
tbh
 
0celouvskyopoulo7
0celouvskyopoulo7
@Cows You're doing $L^p$?
 
Sir Cumference
Sir Cumference
@0celouvskyopoulo7 Well, one man's trash is another man's treasure, I guess
 
0celouvskyopoulo7
0celouvskyopoulo7
@Phase Did you just say I should die?
 
Cows
Cows
@0celouvskyopoulo7 yup!
 
Phase
Phase
Did you just assume my subject
 
0celouvskyopoulo7
0celouvskyopoulo7
5:20 PM
@SirCumference I was trying to toll you, I guess you're learning...
@Phase You're not German
 
Phase
Phase
I'm also not French
or Spanish
 
Sir Cumference
Sir Cumference
@0celouvskyopoulo7 ;-;
 
Phase
Phase
or Japanese
 
0celouvskyopoulo7
0celouvskyopoulo7
@Cows What's unclear to you?
 
Secret
Secret
The line is extremely blurry if you are working in physical chemistry domains such as quantum chemistry, computational chemistry, solid state chemistry, thermochemistry and photochemistry, where a lot of things overlap.

The line is more clear cut for things like organic chemistry, coordination chemistry, where we mostly think of heuristic periodic table trends, and orbitals, and laboratory preparation, reagents and reaction conditions, and does not involve much quantitative analysis
 
0celouvskyopoulo7
0celouvskyopoulo7
5:22 PM
@Cows Let $\mathcal L^p(\Omega)=\{f:\Omega\to\Bbb F\mid ||f||_p<\infty\}$, right?
 
Phase
Phase
@SirCumference Astro is cool, I just hate it because at the levels I've learnt it it's always been memorising formulae and definitions, without any real flexibility in the maths unlike normal classical mechanics questions. i'm sure it's different high up tho
 
0celouvskyopoulo7
0celouvskyopoulo7
So let $\sim$ be an eq. rel. on $\mathcal L^p$ such that $f_1\sim f_2$ if $f_1-f_2=0$ a.e.
 
Cows
Cows
@0celouvskyopoulo7 hang on let me switch to chrome for the mathjax to kick in
 
0celouvskyopoulo7
0celouvskyopoulo7
Then $L^p:=\mathcal L^p/\sim$.
 
Sir Cumference
Sir Cumference
@Phase Don't memorize them. Try to understand them.
Then it becomes cool and fun
 
0celouvskyopoulo7
0celouvskyopoulo7
5:23 PM
Clearly $\mathcal L^p$ has a vector space structure since it is a function space, and you have the Minkowski inequality. So that structure descends to equivalence classes (elements of $L^p$). It's not hard to see how.
 
Secret
Secret
@Phase Yup , it is still impossible, this is why all existing computatonal methods on that are numerical. As for whether that is useful, well our iphones etc. works because of these
 
Phase
Phase
@SirCumference what I meant is that for normal classical mechanics, you can go in knowing things like $L = rmv sin(theta)$, and with a few integrals describe a systems angular motion and how that changes
meanwhile with Astro at the level I've learnt it it's uh...
Very static and seems like number crunching
 
Secret
Secret
@SirCumference Astronomy is a subdomain of physics, but its community has grown large enough to warrant a separate SE site. One cannot claim a subdomain is the domain itself
 
Sir Cumference
Sir Cumference
@Secret Are observational astronomy and telescopy subdomains of physics?
 
Secret
Secret
That honestly I don't have enough background to answer correctly, but IMO, I suspect they are part of astronomy and hence are subdomains of physics
But if you talk about things like astrobiology, astrochemistry, etc., then these are multidiscipline and not a subdomain of anything
 
rob
rob
5:28 PM
 
Sir Cumference
Sir Cumference
I think it's mostly theoretical astronomy that uses physics
Wtf mobile chat...
 
Secret
Secret
@rob I will soon be able to put fine arts, religion, liberal arts, spirituality, etc. into that picture now that my knowledge domain have recently expanded to that
(Villian crackle) On the process of colonising all knowledge domain of humanity
 
Phase
Phase
Is AlbertEinstein still in the chat or has he been banned yet?
 
Sir Cumference
Sir Cumference
@Phase "Yet"?
 
Phase
Phase
Idk, just seems like all the warnings are for naught
 
0celouvskyopoulo7
0celouvskyopoulo7
5:32 PM
What warnings?
I don't think there's a rule against being annoying. At least not unless you annoy mods
 
Phase
Phase
The barrage of short questions
Oh, I figured the warnings were formal, didn't realise it was just "or else I'll ignore you"
Haven't really been as active in the chat so haven't been around to see stuff.
 
Bernardo Meurer
Bernardo Meurer
@JohnRennie Is it reasonable to have a types.h just with all the custom types I need?
 
Cows
Cows
@0celouvskyopoulo7 yes, the book says this too. I just read this part. I am trying to make sense of of some of it. Let me chew on the concept for a while.
 
0celouvskyopoulo7
0celouvskyopoulo7
@Cows are you familiar with quotient vector spaces?
This is exactly the same thing
 
Cows
Cows
Ohhhhh
 
0celouvskyopoulo7
0celouvskyopoulo7
5:40 PM
You have a space $N(\Omega)$ of measurable functions $f:\Omega\to\Bbb F$ with $f=0$ a.e.
 
Cows
Cows
i see
 
0celouvskyopoulo7
0celouvskyopoulo7
You're quotienting $\mathcal L^p$ by $N$.
So $f,g$ are equal in the quotient if $f-g\in N$.
So giving $L^p$ a vector space structure is the same as giving a quotient vector space one
Basic linear algebra
 
Cows
Cows
@0celouvskyopoulo7 perfect!! got it
 
Secret
Secret
5:59 PM
Let me know if I left anyone out:
user image
2
Take home message: Sciences are more well defined in terms of purity
 
0celouvskyopoulo7
0celouvskyopoulo7
@Slereah Currently reading the "Journal of Mathematics and Mechanics"
Seems like a strange name.
 
Slereah
Slereah
what, all of it?
 
0celouvskyopoulo7
0celouvskyopoulo7
Yeah
There's only like 300 volumes
@Slereah please save me
 
Slereah
Slereah
6:16 PM
of what
 
0celouvskyopoulo7
0celouvskyopoulo7
PDE
I have a headache
 
Slereah
Slereah
close the book
 
0celouvskyopoulo7
0celouvskyopoulo7
not a book
 
Bernardo Meurer
Bernardo Meurer
@dmckee I want templating in C :P
So that I can have the same linked list structure for multiple types
Actually
I got a question @JohnRennie @dmckee
 
Slereah
Slereah
close your eyes
 
dmckee
dmckee
6:20 PM
@BernardoMeurer People used to do that with code-generation schemes. Now they just write is the c-like subset of c++.
 
Bernardo Meurer
Bernardo Meurer
Suppose I have a CSV file, I've read it into memory (char*) and I'm now parsing it into a data structure. What's the best way of doing this?
 
dmckee
dmckee
I found a open source library for that once.
 
Bernardo Meurer
Bernardo Meurer
If I do a m/calloc I'll need to realloc after every line to add the next thing
 
dmckee
dmckee
It respects the RFC and everything.
 
Bernardo Meurer
Bernardo Meurer
No libraries out of the standard allowed :/
 
dmckee
dmckee
6:21 PM
You did know there was an RFC that everyone ignores, right?
 
Bernardo Meurer
Bernardo Meurer
Should I do a linked list?
There's an RFC?
 
dmckee
dmckee
@BernardoMeurer SO there are two separate questions here. Te first is "how should I parse the file?" and the second is "How should I store or manage the results?".
 
Bernardo Meurer
Bernardo Meurer
@dmckee I'm parsing with strtok, is that not good? Using "\n," as a delimiter for the tokens
 
dmckee
dmckee
And the answer to the second depends on how you are going to use the data.
 
Bernardo Meurer
Bernardo Meurer
I already have a structure that holds a single entry 
typedef struct bikeStation {
    unsigned int ID;
    id terminal;
    char *name;
    char *city;
    coord location;
    bool status;
} station;
 
dmckee
dmckee
6:23 PM
@BernardoMeurer It's hard to make it respect the RFC (or any scheme for escaping commas).
 
0celouvskyopoulo7
0celouvskyopoulo7
bool?
 
Slereah
Slereah
boolean
 
0celouvskyopoulo7
0celouvskyopoulo7
 
dmckee
dmckee
It's better to write a state machine or a recurse desecnt parser.
 
0celouvskyopoulo7
0celouvskyopoulo7
Oh
 
dmckee
dmckee
6:24 PM
But for a class assignment you may not need that. Read the spec carefully.
 
Bernardo Meurer
Bernardo Meurer
@dmckee Is it worth the trouble? to just parse a simple CSV?
I don't need it to be general or anything 
id,terminal,station,municipal,lat,lng,status
3,B32006,Colleges of the Fenway,Boston,42.340021,-71.100812,Existing
4,C32000,Tremont St. at Berkeley St.,Boston,42.345392,-71.069616,Existing
5,B32012,Northeastern U / North Parking Lot,Boston,42.341814,-71.090179,Existing
6,D32000,Cambridge St. at Joy St.,Boston,42.361285,-71.06514,Existing
 
dmckee
dmckee
@BernardoMeurer The state machine is maybe 40 lines. But "Is it worth it" depends on the input. Will there be escaped commas or not?
 
Bernardo Meurer
Bernardo Meurer
I just need to parse that into the structure I presented
No escaped commas
 
dmckee
dmckee
Then strtok will work. Leaving aside its horrifying use of local static storage.
::shudder::
 
Bernardo Meurer
Bernardo Meurer
I was thinking of reimplementing this
Because it handles blank tokens
Which I need for the other CSV I gotta parse
@dmckee But the question remains, do I do a linked list or do I just do a malloc and then reallocs
@dmckee I'm going with linked list
Cause realloc() is slow af
 
Bernardo Meurer
Bernardo Meurer
6:51 PM
@dmckee Is it easier to quicksort and manipulate doubly linked lists?
 
Sir Cumference
Sir Cumference
0
Q: Comment votes can be easily gamed

Sir CumferenceWhen someone deletes an account, the upvotes they left on comments are not removed. When they create another account, they can upvote these comments once again. This is a huge problem, as you can give a comment as many upvotes as you want by: Upvoting the comment Deleting your account Repeatin...

bug comments voting deleted-accounts gaming-the-system
This is bad
 
Bernardo Meurer
Bernardo Meurer
@SirCumference Read your last paragraphs
 
Sir Cumference
Sir Cumference
@BernardoMeurer What?
 
Bernardo Meurer
Bernardo Meurer
This can even be done very quickly, since upvoting a comment doesn't require you to contact SE to delete your account (the "Delete" button will remain in your profile settings).
This makes little sense
 
Sir Cumference
Sir Cumference
What doesn't make sense about that?
Jesus christ backlash
 
0celouvskyopoulo7
0celouvskyopoulo7
7:07 PM
@ACuriousMind algebraic bat signal
 
dmckee
dmckee
@BernardoMeurer The mechanism will look a little different, but I am sure you can do it.
@SirCumference Don't rile the meta.
 
Bernardo Meurer
Bernardo Meurer
struct Node* GetNewNode(int x) {
	struct Node* newNode
		= (struct Node*)malloc(sizeof(struct Node));
	newNode->data = x;
	newNode->prev = NULL;
	newNode->next = NULL;
	return newNode;
}
 
dmckee
dmckee
But seriously, the way to deal with it is not to give any weight to comment votes in considering arguments.
 
Bernardo Meurer
Bernardo Meurer
@dmckee Why the heck do people use structs for that and not a void func?
 
dmckee
dmckee
Tell people to put it in an answer and see how the real votes fall.
 
Sir Cumference
Sir Cumference
7:10 PM
@dmckee What do you mean?
 
dmckee
dmckee
In some case you can also flag the comments as noise to be deleted.
 
Sir Cumference
Sir Cumference
@dmckee But darn, I was not expecting such opposition
 
dmckee
dmckee
@SirCumference Comments that people might care to falsely amplify are mostly on meta. On meta we are a bit more forgiving about topicality of answers. So ask the author of the comment to make an answer of it.
You can do the same on the main site if the comment is a pseudo-answer.
Some of are more pernicious trolls have been forced to mightily resist that, making it clear that they know the way their notions are perceived.
 
Bernardo Meurer
Bernardo Meurer
Ah, nevermind that question
I was being stupid
 
dmckee
dmckee
Then they fall back on, "its a consipracy", but it makes the situation clearer to casual readers.
 
Sir Cumference
Sir Cumference
7:14 PM
@dmckee Well, some of the people resisting have >50k rep on some sites
 
dmckee
dmckee
@SirCumference Hmmm ... I think you may have misunderstood my suggestion. I'm saying that we have a work-around for the problem you want to solve: push commenters to commit their ideas to answers where they can't easily falsely increase the vote count.
That is, I'm not worried about comment vote counts and don't feel the team needs to rush out and do anything about it.
 
Sir Cumference
Sir Cumference
@dmckee I suppose, but then what's the point of having comment counts if they're broken anyways?
 
dmckee
dmckee
I'm pretty sure I can guess how many votes a stupid comment on meta.physcis will get because I know which users feel that way. And that implies that people aren't falsiely inflating their counts.
 
ACuriousMind
ACuriousMind
I don't understand what the problem here is - can 1 rep users upvote comments?
 
dmckee
dmckee
They are mostly not broken: they are breakable, but there is no payoff in it, so it rarely happens.
 
Sir Cumference
Sir Cumference
7:18 PM
@ACuriousMind Anyone with the association bonus can game them
 
Bernardo Meurer
Bernardo Meurer
@dmckee I need a tip on naming schemes. I have two types, station and trip, each has an associated doubly-linked node type named station_n and trip_n. I'm implementing utility functions (add node, remove, etc) for both. What to name, for example, the insertHead() function for each of the types?
 
ACuriousMind
ACuriousMind
@SirCumference See, that's not clear at all from your meta post. So, the issue here is that deleting an account on one site and then immediately recreating it allows me to upvote comments again?
 
Sir Cumference
Sir Cumference
@ACuriousMind Yup
 
dmckee
dmckee
@BernardoMeurer That's why c needs namespaces.
 
ACuriousMind
ACuriousMind
Also, the post is not quite clear on how you came by this information - did you test that yourself?
 
Bernardo Meurer
Bernardo Meurer
7:19 PM
Meh, templates would solve it
But I ain't got those either :P
 
dmckee
dmckee
I usually go with inertFooAtHead() and the like.
 
Bernardo Meurer
Bernardo Meurer
Yeah, that's reasonable I guess
@dmckee Am I wrong to always use calloc()?
 
dmckee
dmckee
@BernardoMeurer Template need a name mangling scheme which is the infrastructure upgrade needed for namespaces, too.
 
Bernardo Meurer
Bernardo Meurer
I just like to stay safe
 
Sir Cumference
Sir Cumference
@ACuriousMind Yeah, I noticed that, when I deleted my account, the upvote remained
I haven't abused it, of course
 
Bernardo Meurer
Bernardo Meurer
7:21 PM
@dmckee Aha! I did not know that :)
But C ain't getting neither templates nor namespaces I'm afraid. But to be fair I don't even know what's in C11
 
dmckee
dmckee
@BernardoMeurer It is traditional to default to malloc unless you known you want the zeros because there is no guarantee that calloc is as fast as malloc.
 
Bernardo Meurer
Bernardo Meurer
@dmckee I just like calloc better because it handles the allocation size arithmetic with failsafes
 
dmckee
dmckee
But that tradiation has it roots in the days when computers were slow, and arguably the repeatability of bugs you get using calloc is worth it today.
 
0celouvskyopoulo7
0celouvskyopoulo7
@ACuriousMind ?
 
ACuriousMind
ACuriousMind
@0celouvskyopoulo7 !
 
0celouvskyopoulo7
0celouvskyopoulo7
7:23 PM
Yes, no?
Too drunk to answer?
 
ACuriousMind
ACuriousMind
Not drunk, but not sure what to answer
 
0celouvskyopoulo7
0celouvskyopoulo7
@ACuriousMind My algebra question
 
Bernardo Meurer
Bernardo Meurer
@dmckee Just read on the C11 changes, nothing special there, apart from threading
 
ACuriousMind
ACuriousMind
@0celouvskyopoulo7 where is it?
 
0celouvskyopoulo7
0celouvskyopoulo7
@ACuriousMind In my head
Do you want me to ask it?
 
ACuriousMind
ACuriousMind
7:24 PM
When I start answering questions in your head you might need help ;P
Ask away
 
0celouvskyopoulo7
0celouvskyopoulo7
@ACuriousMind I was just testing if you can read my mind.
Just to...make sure.
 
ACuriousMind
ACuriousMind
If I could, would I not have also read that and avoided giving it away?
 
0celouvskyopoulo7
0celouvskyopoulo7
@ACuriousMind You might have thought "oh, I missed it!" then read my mind to obtain the question, rather than looking for it and concluding I never posted it.
Ugh, this is a technical question
@ACuriousMind I don't think the Sobolev spaces are important here, it really is just the linear algebra. I have a function $u\in W^{2,q}_\delta$, and I know that $\Delta u\in W^{0,q}_{\delta-2-\tau}$. Now $\Delta :W^{2,q}_{\delta-\tau}\to W^{0,q}_{\delta-\tau-2}$ is Fredholm (finite dimensional kernel and cokernel).
So the idea is to show that in $E_R=R^n-B_R$, we can find $v\in W_{\delta-\tau}^{2,q}$ with $\Delta u=\Delta v$.
And it's remarked that this cannot generally happen in all of $R^n$.
 
Sir Cumference
Sir Cumference
@dmckee Uuuugh
C'mon...
 
0celouvskyopoulo7
0celouvskyopoulo7
So in a sense, $\Delta$ is surjective on $E_R$...
I want to argue as follows: $\coker \Delta$ is finite dimensional.
 
dmckee
dmckee
7:32 PM
@SirCumference Look, I think it is cool that you've found a technical flaw in the system. Well, done. You get the 'Genius of the Moment' award (Savior it quickly it moves on fast!), but there is no evidence it is a big problem.
 
0celouvskyopoulo7
0celouvskyopoulo7
So the image of $\Delta$ only misses finitely many linearly independent functions on $R^n$
 
Sir Cumference
Sir Cumference
@dmckee Sigh...
 
0celouvskyopoulo7
0celouvskyopoulo7
So I claim that the functions that $\Delta$ misses are characterized by their values inside of $B_R$
 
Sir Cumference
Sir Cumference
I think I'll just give up, no one's listening to the other
 
Sha Vuklia
Sha Vuklia
Guys, sorry to interrupt, but I have one question. What was the main motivation to define potential energy? I understand that the potential is a scalar field, as opposed to the vector field of a force, so that is nice. However, why did we associate this quantity with energy?
 
0celouvskyopoulo7
0celouvskyopoulo7
7:34 PM
Because if $\Delta$ misses some function defined on $E_R$, then I can change the values arbitrarily in $B_R$ to produce more such functions
 
Sha Vuklia
Sha Vuklia
I understand that the work done by a force was practically defined as the change in kinetic energy, so was part of the purpose of defining potential energy in this way that we would have a sum (kinetic energy + potential energy) that is always constant, which is in line with our assumption that the total energy of an isolated system remains constant?
I’ve always just seen it as a definition, but I’m wondering if this really is the “motivation” or maybe intuition behind it. I keep forgetting that a (conservative) force is the negative of the derivative of the potential, because I just don’t have any intuition for it.
 
0celouvskyopoulo7
0celouvskyopoulo7
And eventually end up with an infinite dimensional cokernel
Now that I say that, it sounds nothing like what was in my head
@ACuriousMind Did that make any sense at all?
I think my idea is right though, I just need to formulate it precisely.
@ACuriousMind The idea is that if $\Delta$ cannot reach this magical $f$ outside of $B_R$, I can just change $f$ inside of $B_R$ (without leaving the Sobolev space) to create a bunch of functions it misses on all of $\Bbb R^n$. This contradicts the Fredholm hypothesis.
 
Bernardo Meurer
Bernardo Meurer
@dmckee If I want to compare structures can I just do a memcmp?
 
AccidentalFourierTransform
AccidentalFourierTransform
@SirCumference argh, what's wrong with people?
I dont get it
 
Sir Cumference
Sir Cumference
Thank you
It just baffles me
 
AccidentalFourierTransform
AccidentalFourierTransform
7:42 PM
I mean, I get that it might not be a top priority
but it is a very valid point
they could, you know, just say "yeah, we'll keep this in mind. Thanks"
but for some reason they are trying to argue that your post is pointless and nothing really matters
whatever
 
Sir Cumference
Sir Cumference
@AccidentalFourierTransform I know right? It can actually be a problem, but they're now arguing that upvoting comments is pointless
Way to ignore that a system is broken
 
AccidentalFourierTransform
AccidentalFourierTransform
are they really trying to argue that a comment with 40+ upvotes will have the exact same impact than one with no upvotes!? that they are to all purposes equivalent!? have they ever used SE!?
 
00:00 - 09:0009:00 - 10:0010:00 - 14:0014:00 - 16:0016:00 - 20:0020:00 - 00:00

« first day (2384 days earlier)      last day (2528 days later) »