#serious-discussion

1 messages · Page 37 of 1

bright hill
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I know diff geo is really big for GR and stuff

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But that's about it opencry

rocky shuttle
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Essentially, what I wanted to cover today is how to integrate differential forms on manifolds and Stokes' theorem, which is an extension of the fundamental theorem of calculus

zealous garden
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hmm....

rocky shuttle
bright hill
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Oh, don't worry, i dont give a crap about GR so Lee won't be necessary for now lmao

zealous garden
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I care about GR

rocky shuttle
# bright hill I know diff geo is really big for GR and stuff

I'm not an expert in GR. I have a colleague who is doing numerical analysis in GR. The only thing I can say is perhaps that GR uses the language of differential geometry to formulate the Einstein field equations, which describes the curvature of spacetime. So mass tells spacetime how to curve and spacetime tells mass how to move.

zealous garden
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should I skip spivak and go to Lee

bright hill
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Spivak is a prereqs for lee, i think

rocky shuttle
zealous garden
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idk I really enjoyed Taylor's treatment of integration on manifolds

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I'd be willing to go through something like that again just because it was kinda fun

rocky shuttle
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My path to differential geometry was very messy. I started with Optimization Algorithms on Matrix Manifolds by Absil, because the course I had in my uni was quite application-oriented. Then I picked up Vector Analysis by Jänich. Then Lee, Do Carmo, and Spivak.

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Ok, how to motivate it... Have you done some integration in physics? Like computing the work done along a path in some gravitational field? Or computing the flux of an electric field through a surface given some distribution of electrical charge?

bright hill
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I don't know much physics over all lel

mint canopy
zealous garden
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sorry I can't do discrete geometry yet

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I'm still learning differential geometry

surreal kindle
rocky shuttle
# bright hill I don't know much physics over all lel

Ok, so, maybe you have heard in school that the work done by lifting some mass $m$ over some height difference $Δh$ with gravitational acceleration $g$ is given by $$W = F Δh = m g Δh,$$ where $F$ is the gravitational force. Turns out, we can generalize it to arbitrary force fields by considering the line integral $$W = \int_{\Gamma}F\cdot dS,$$ where $\Gamma$ is the path we're integrating over and $F\cdot dS$ is a differential 1-form.

fathom swallowBOT
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Zanarcane

rocky shuttle
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Usually, physics and engineering students memorize that the above line integral is given by $$W=\int_{\Gamma}F\cdot dS=\int_{a}^{b}F(\gamma(t))\cdot\dot\gamma(t)dt,$$ where (\gamma\colon[a,b]\to\mathbb{R}^3) is a parameterization of the path / curve / 1-dimensional manifold (\Gamma). But it's quite insightful to learn the general formulation using differential forms.

bright hill
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Are you looking for $\mathbb{R}$?

fathom swallowBOT
rocky shuttle
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One particular interesting thing is that if the force field F is conservative, then the work done along any path only depends on the starting and end point.

fathom swallowBOT
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Zanarcane

rocky shuttle
bright hill
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I use \bR haha

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You can request a preamble edit later if you want

rocky shuttle
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Especially, if the path is also closed, i.e., starting and end point are the same, then the work done is 0, according to our intuition.

rocky shuttle
rocky shuttle
fathom swallowBOT
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Zanarcane

rocky shuttle
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You can also see the FTC as a telescoping sum in the discrete case, i.e., given a finite sequence $x_i$ for $i=0,...,n$, the sum of differences reads $$\sum_{i=1}^{n}\Delta x_i=\sum_{i=1}^{n}x_i-x_{i-1}=x_n-x_0.$$

fathom swallowBOT
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Zanarcane

rocky shuttle
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I quote @zealous garden

the accumulation of the differences inside, is the same as the accumulation of the values outside

zealous garden
rocky shuttle
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And this applies to the more general case, where you integrate over n-dimensional manifolds, summarized in Stokes' theorem

bright hill
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This feels waay too wishy-washy ngl

rocky shuttle
bright hill
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Fair lmao

rocky shuttle
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I like this segment after the proof of Stokes' theorem for chains in Spivak

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So the work is in defining the mathematical objects, such as differential forms, boundary of a chain, etc. properly, then Stokes' theorem follows directly from the FTC in 1D.

bright hill
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oooo

zealous garden
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basically

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I had stokes' theorem proved as a special case of the FTGC

bright hill
zealous garden
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Geometric

rocky shuttle
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oh right, didn't need to ask

rocky shuttle
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I assume that FTGC uses FTC in the proof?

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Some people say that Stokes' theorem is a generalization of FTC, but I think extension is the better word

zealous garden
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the way It's often introduced is that Stoke's Theorem is a generalization of FTC, and FTGC is a generalization of stokes' theorem

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it doesn't look like this proof uses the FTC directly, but it does do a few telescoping sums

rocky shuttle
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I can't imagine it not using FTC, hmm

zealous garden
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it might have to do with the way Taylor chooses to phrase it

frail lagoon
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gm

zealous garden
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the trick with the FTGC is that the basic form looks just like stoke's theorem with forms, but apparently there are a lot of choices that go into getting that presentation

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like you need to establish your orientation

frail lagoon
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yeah proving stokes has been among the most disappointing moments of my maths career

zealous garden
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then when you have an orientation established, it has to induce an orientation on the boundary

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which gives you some options

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i.e. for an orientation $w$, we have the choice of $w$ and $w^{\dagger}$ for orientation, which can be taken in combination with a normal vector $n$ to the boundary to induce an orientation on the boundary by $\partial w = w n$ or $\partial w = n w$ or $\partial w = w^{\dagger} n^{\dagger}$ etc etc.

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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I think there are like 6-8 different choices you could make to define the way that an orientation on a boundary is induced by an orientation on the interior

frail lagoon
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wew daggers

zealous garden
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furthermore, when differentiating we have to decide whether we mean $\nabla = e^i \partial_i$ or $\nabla = \partial_i e^i$

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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and then we have to, again, make a similar choice with integration, distinguishing between $\int dx F$ and $\int F dx$

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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so we usually run with:

$\overrightarrow{\partial} w = n w \ \overleftarrow{\partial} w = w n$

$\overrightarrow{\nabla} = \partial_i e^i \ \overleftarrow{\nabla} = e^i \partial_i$

$\int F = \int \overleftarrow{\partial}w F$ (for Multivector Fields)

rocky shuttle
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uhhh, alright, what does dx F mean? I'm familiar with F dx = F ∧ dx = -dx ∧ F, is it the same?

zealous garden
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so

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dx F means that you combine dx and F with the geometric product

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oh wait

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I'm mixing notations

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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that juxtaposition is the geometric product

rocky shuttle
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wew

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completely new language for me

zealous garden
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dx (now replaced with del w) is a pseudoscalar of the tangent space

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that is $\bigwedge_i dx^i$

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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the reason we have these disagreements is because the geometric product in general fails to commute or anti commute

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using this notation, the direct analogue of stoke's theorem looks like

$\oint_{\partial M} f \overrightarrow{\partial w} = \int_M \overrightarrow{\nabla} f w$ or

$\oint_{\partial M} \overleftarrow{\partial w} f = \int_M w \overleftarrow{\nabla} f$

fathom swallowBOT
#

wraithlord_kotopology

zealous garden
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which actually generalizes further, we can multiply on both sides of del(w) (formerly dx), this one is a doozy

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$\int_{\partial M} f (\overrightarrow{\partial} w) g = \int_M \overrightarrow{\nabla} f ( w ) g + (-1)^{m - 1} \int_M f (w) \overrightarrow{\nabla} g$

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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with the left-handed version being what you likely expect

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let g = 1 and we recover the first version I showed

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the geometric derivative (nabla with the arrow on it) is a dirac operator, it's basically the exterior derivative + the codifferential

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so the final bits we need to turn this into stokes' theorem are a way to translate between multivector fields and differential forms, and to integrate forms over manifolds

rocky shuttle
zealous garden
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it suffices to identify differential forms with multivector fields that remain unchanged when projected onto the manifold, and to identify the exterior derivative with the curl (the grade-raising portion of the geometric derivative) projected onto the manifold

zealous garden
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the last tricky+gross part, is the definition of integration for these "differential forms"

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$\int_M \omega = \int_M \langle w^{\dagger} f \rangle_0$

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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where f is the multivector field representing the differential form omega

rocky shuttle
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ok, a lot of things I need to look up the definition of

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the angle brackets mean projecting onto the 0-blade space?

zealous garden
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in GA <F>_n means "extract the nth grade part of F"

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so that means the scalar part of that geometric product

rocky shuttle
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ok

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and orientations here are just either -1 or +1?

zealous garden
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orientations (w) are pseudoscalars, I picture them as infinitesimal pieces of the manifold

rocky shuttle
zealous garden
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and they are unitary

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so -1/+1 in 1D

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then we also have that w^2 = \pm 1, depending on the dimension of w

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i.e. in 1 it's 1, in 2,3 it's -1, in 4 it's 1

rocky shuttle
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is wn = -nw?

zealous garden
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wn = (-1)^m nw

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I think

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might be m-1

rocky shuttle
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oh, yeah dependence on the dimension

zealous garden
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now to prove stokes' theorem as a special case.
we want: $\ \int_{\partial M} \omega = \int_{M} \text{d} \omega$

which according to our definitions of integrating forms becomes

$\int_{\partial M} \langle (\overrightarrow{\partial} w)^{\dagger} f \rangle_0 = \int_{M} \langle w^{\dagger} \overleftarrow{\text{d}} f \rangle_0$

fathom swallowBOT
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wraithlord_kotopology

rocky shuttle
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What happened to the codifferential?

zealous garden
# fathom swallow **wraithlord\_kotopology**

we can simplify the (not pictured, left-handed version of the) two-sided fundamental theorem directly with f=1, g=f, and w=w^\dagger

$\int_{\partial M} \overleftarrow{\partial}(w^{\dagger})f = \int_M w^{\dagger} \overleftarrow{\nabla} f$

fathom swallowBOT
#

wraithlord_kotopology
Compile Error! Click the errors reaction for more information.
(You may edit your message to recompile.)

zealous garden
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this means that the codifferential lowers the grade, then the orientation sends it to the opposite dimensionality, where it gets ignored because it's definitely not in the scalar part

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which is what we care about

rocky shuttle
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I see

zealous garden
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as the next manipulation from here, we take the scalar part and basically walk through the reasoning I just outlined

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along with a short lemma about projection onto manifolds

rocky shuttle
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What's your main reference for GA?

zealous garden
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and it shows that $\langle w^{\dagger} \overleftarrow{\nabla}f \rangle_0 = $\langle w^\dagger \overleftarrow{\text{d}} f\rangle_0$, which after substituting back in and using our definitions, yields the theorem

fathom swallowBOT
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wraithlord_kotopology
Compile Error! Click the errors reaction for more information.
(You may edit your message to recompile.)

zealous garden
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it's cheaper than something like Snygg's Diff Geo with GC or Hestenes' "From Clifford Algebra to Geometric Calculus"

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while being more rigorous and detailed than Alan MacDonald's LAGA and VAGC

rocky shuttle
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Oh, there is a crash course written by Taylor

zealous garden
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but Taylor's notation (the one I've been using up to now) is one I have strongly mixed feelings about

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like where taylor has w and del w, macdonald has d^m x and d^(m-1) x

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but then where taylor takes time to develop what the fuck a manifold is and how to integrate over one properly

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macdonald only goes so far as to talk about open subsets of R^n

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with most proofs omitted

rocky shuttle
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Wait, are those cross products?

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or x

zealous garden
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well macdonald chose $d^m x$, because $\text{d}^m \mathbf{x} = \text{d} x^1 \wedge \ldots \wedge \text{d} x^m$

fathom swallowBOT
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wraithlord_kotopology

zealous garden
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and putting the exponent over the x just looks like the tangent vector

rocky shuttle
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aha

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I skimmed the crash course, looks quite manageable

zealous garden
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my problem with both so far is that their material stays pretty firmly in the realm of Geometric Algebras with positive signature

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which excludes things like Conformal Geometric Algebra, Spacetime Algebra, and Projective Geometric Algebra (the first two have pseudo-riemannian metrics, the last has a degenerate form)

frigid matrix
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@zealous garden @zealous garden what is geometric algebra

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also isnt the notation to do dx^I where I indexes over x^i

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d^m x is not canon

zealous garden
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Geometric Algebras are Clifford Algebras, perhaps with the stipulation that they are over the Reals

frigid matrix
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the only correct notation is lee

zealous garden
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Clifford called them Geometric Algebras before his death

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And the people who call them Clifford Algebras usually have very different intentions than those who call it a Geometric Algebra

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Like talk of Clifford algebras sometimes completely skip over the grading, but that's a central aspect to anyone doing Geometric Algebra

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So in Geometric Algebras we typically care about interpretations of Clifford Algebras for representing and manipulating some Geometric space

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Like in VGA (Vector Geometric Algebra), the simplest kind

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Where the different k-vectors are used to represent k-dimensional subspaces, reflections, rotations, dilations, and oriented k-dim volume segments

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Or in something a bit more complicated like Projective Geometric Algebra (3,0,1), where we have planes, points, lines, and translations as well

frigid matrix
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oh cool

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thanks for explanation @zealous garden

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i have seen definitions of clifford algebra when looking at a gauge theory thing. but i do not know the various uses besides potentially mathematical physics. if i remember correctly it has something to do with this thing called a killing form?

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and usually clifford algebras are parameterized by a field its over and a dimension?

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iirc

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let Q be a killing form?

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then clifford algebra is n’th tensor product quotient the set of vectors that vanish with Q?

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im not sure exactly but its something like this

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im curious if it comes up in contexts other than physics do you know?

zealous garden
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Ah the tensor definition yeah

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So you take the tensor algebra and quotient it by the ideal generated by uv + vu - 2q(u,v) for a bilinear form q

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Clifford Algebras are most used in math phys to my knowledge

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Geometric Algebras are most used in physics, engineering, computer graphics and computer vision

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Where they subsume things like the quaternions and dual quaternions

zealous garden
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in math phys clifford algebras subsume things like spinors and twistors

frigid matrix
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o

alpine kindle
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because in char 2 they're not equivalent

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or sth

zealous garden
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A quadratic form is actually too general

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And that (v^2) doesn't use all of the bilinear form like we need/want

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Maybe I did get the divisor of the quotient wrong though, I'm not entirely used to that

alpine kindle
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this is what it says on wikipedia

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it says lower down that if char ≠ 2 this is equivalent to what you said

zealous garden
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Gotchu

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I see

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So it turns out that is also one of the differences

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Clifford Algebras generally accept a quadratic form

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We prefer to restrict Geometric Algebras to bilinear forms

alpine kindle
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can't you define a quadratic form from any bilinear form and vice versa

zealous garden
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Idk if it goes both ways but I know bilinear forms go to quadratic forms

alpine kindle
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if you have a quadratic form $Q$, you can define a symmetric bilinear form $B$:
$$B(u,v) = \frac{Q(u+v) - Q(u) - Q(v)}{2}$$

fathom swallowBOT
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Ally (ea/eam/eius)

alpine kindle
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(also from wikipedia 😵‍💫)

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this obviously doesn't work in char 2 so uhh

static loom
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so ignore it 😎

bright hill
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New merosity pfp less goo

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Is that ai generated? Lel

static loom
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haha no, just a wilted rose that happens to look kind of like a skull

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halloween theme

bright hill
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Cool

neat lintel
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@ember dawn @void holly look, im not saying we need to use that here, but this isnt physics. The whole point of math to assure this sort of accuracy

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If you will make a function that is partially satisfying why make it at all?

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You cant just exclude 0 from the inputs

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Just saying,

ember dawn
void holly
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honestly, it's not about literally buying 0 books. it's about showing that there is a $3 initial fee that you will always pay for some number of books (technically must be a positive number). that's why so many of these kinds of questions exist, they're not literally saying to plug in 0 and solve for the price when someone "buys 0 books"

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they're not really concerned about domain and stuff at this level

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i kinda worded that weird but yeah i hope it makes sense lol

neat lintel
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Thats like, the whole point of mathematics

icy crag
chrome pewter
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only in ohio

severe swallow
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wtf who says these overleaf cv templates look good? I'm browsing through them to find a good one but they all look like shit

surreal sapphire
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moderncv looks fine?

severe swallow
surreal sapphire
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A curriculum vitæ or résumé has a universal requirement: its formatting must be flawless. This is a great example of cases where the power of LaTeX comes to the front.
Thanks to its strong typographical stance, LaTeX is definitely a document processor of choice to write a CV.
Of course you can design your own CV by hand. Otherwise, you may want ...

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though i would just learn how to use the package and not copy-paste some template

severe swallow
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well, I really don't wanna get into studying the package but eh....

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if this is considered a decent cv, I guess cvs just look really unappealing in general

surreal sapphire
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i dont know what kind of look you want

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its just a table

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imo less is more

severe swallow
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yes, I'm not looking for something that does a lot, but it still should have an aesthetic that makes an eye want to look at it.

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I mean it shouldn't be something that looks like spaced out text editor file

deep mango
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im surprised you don't think something like this looks good

deep mango
severe swallow
surreal sapphire
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you can always learn like html+css and make it yourself monkey

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this is just standard moderncv

severe swallow
deep mango
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like this stuff is so dumb to me

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i get it

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but also

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what do the little skill bars at the bottom mean!?

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this isn't a fucking mmorpg

surreal sapphire
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maybe if you apply for a designer job

severe swallow
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yeah these bars are ridiculous lmao

deep mango
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maybe this appeals to hiring managers at a tech firm or something

severe swallow
deep mango
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but if you're writing a CV, for an academic job, no one cares about things looking like this. they'll be happier if you just have it in the format everyone has it in

surreal sapphire
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tbh i think a default moderncv one also looks good

severe swallow
surreal sapphire
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i had a cv done "professionally" a few years back

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and it was done in word

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it looks horrible

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and my moderncv one looks way better

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i assume random word one is the default and just using latex makes it look special

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though maybe in academia using moderncv is standard

surreal sapphire
# deep mango

also the main issue here from a hiring perspective is not listing months, only years

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this way it appears as if the person is trying to hide stuff

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i know because i do the same monkey

severe swallow
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alright I'll try to suffer my way through this package

severe swallow
deep mango
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hired december fired january sotrue

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2 years experience

surreal sapphire
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like if you quit a job january 2020 and get a new one december 2020, you can hide that by just listing years

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old job: xxxx - 2020
new job: 2020 - xxxx

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this hides almost a full year of unemployment

severe swallow
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is this really that much of an issue if you've been in academia meanwhile?

surreal sapphire
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if you are unemployed, you arent in academia

severe swallow
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ah..... well ok then

surreal sapphire
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maybe replace unemployed with NEET

severe swallow
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"trying to read hartshorne" 2020-2022

surreal sapphire
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i mean yeah, you can explain periods of being NEET

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but it doesnt look good on a glance

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thanks capitalism

severe swallow
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well, I'm still in my masters, so this I don't have to worry about yet

bright hill
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That's legit so cringe lmfao

surreal sapphire
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tfw fishing 99

severe swallow
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but I guess I'll have to be a nonstop hustler if I don't want awkward gaps like this in my cv

surreal sapphire
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i mean my opinion is idc fuck them

woven whale
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math level 69

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doing calculus 17

surreal sapphire
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but if you dont have gaps, the standard way is to list months too

severe swallow
rocky shuttle
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I would put lorem ipsum in my cv, yes

ember vale
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Why there aint no game theory server here?

rancid meadow
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tons of tech resumes will have like a skill section w different tiers of understanding

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i just list all my shit in one line bc i’m the best at everything i do but

deep mango
bronze pelican
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So much space wasted in the left column

deep mango
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Ikr

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Put the dumb progress bars there

rancid meadow
long matrix
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ryc is dumdum

fair mural
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true

covert geyser
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I have a simple logic question: if one is one and one also counts for two what does two count for

vivid halo
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what

covert geyser
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yes

upbeat mesa
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Is it possible to have a circle but only have a single interior point with all its surrounding points being a boundary?

storm sage
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what do you mean?

upbeat mesa
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Like an infinitely small circle that goes around a single point

storm sage
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you can't have that in euclidean geometry (the sort of geometry you do in high school), but you can define that yea

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I imagine it'll have really weird properties

upbeat mesa
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ok cool thanks, got a dumb idea cooking up and im trying to see if its even worthwhile

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Considering if I should just define it as a collection of points around a point that may or may not include an object

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Though not sure that would work but I can dream

zealous garden
storm sage
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wdym?

zealous garden
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To have an interior be a single point

storm sage
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I'm sure you can consider this set and define a topology on it

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the only neighbourhood including the interior would be the whole thing, I guess

zealous garden
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Yes

rocky shuttle
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My intuition fails for non-metrizable spaces

zealous garden
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But if we still think of a circle as a collection of points equidistant from another point

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Then it's a circle with "smallest possible" radius

eager reef
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I mean

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The interior is open

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So you’d have that singletons are open

zealous garden
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That's not the issue, the issue is the boundary part

alpine kindle
eager reef
eager reef
alpine kindle
eager reef
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i guess we could try the discrete topology

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look at some point and the ball around it with radius <=1

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that's the entire space

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but i'm not sure rn if the interior of that ball is the ball of radius <1 rn

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it's not true for every metric space

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for the discrete topology on {0,1} it isn't for example

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so a discrete space where this holds would be an example i guess?

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actually i think that cannot work

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well, whatever monkey

storm sage
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I was thinking it'd be the same as the metric topology except you remove the singleton set containing the center from the topology

alpine kindle
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actually this can work as the subspace topology of R²-{x : 0 < |x| < 1}

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where the disc they mention is the closed ball $\overline{B_1(0)}$

fathom swallowBOT
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Ally (ea/eam/eius)

storm sage
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that's what I was thinking but it's kinda weird for the singleton center point to be an open set imo

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so I excluded it

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I'm p sure that's still a topology

rocky shuttle
storm sage
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?

rocky shuttle
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so, the singleton center is open

storm sage
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how is the complement closed

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or rather, why should be the complement be defined as closed

rocky shuttle
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relative to R²-{x : 0 < |x| < 1}

storm sage
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well yes but I'm not using the subspace topology

rocky shuttle
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ah

storm sage
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I'm using the subspace topology minus the singleton center point

rocky shuttle
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I see

alpine kindle
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and they stated that the interior was one point

rocky shuttle
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@alpine kindle I'm curious, how did you manage to learn a lot of concepts in math at your age? When did you start?

alpine kindle
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idk when exactly i started

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or even how to quantify when i properly started

storm sage
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oh it needs to have an interior?

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I see

alpine kindle
rocky shuttle
alpine kindle
storm sage
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I wonder if they meant interior in the topological sense or if it was just a casual description

alpine kindle
rocky shuttle
alpine kindle
alpine kindle
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more like a miz phase but for much shorter and less pronounced

rocky shuttle
alpine kindle
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like

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the wikipedia page popped up in relation to something or other

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and i realised i was out of my depth

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but eventually I'd read around enough that i could actually understand a bit of what was being said there

rocky shuttle
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Yeah, the wiki rabbit hole...

alpine kindle
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and we eventually get to now where I'm trying to prove the inverse function theorem without much prior formal analysis experience

rocky shuttle
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I'm a little bit jealous tbh, I never had a "proper" math education in school and only started to see the beauty in college

alpine kindle
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the maths education in school here is pretty good

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the issue is that it's all so easy

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when you've already done it a million times

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2 years before

rocky shuttle
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schools tend to repeat things, is that what you mean?

alpine kindle
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no

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i mean I've done it on my own

rocky shuttle
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oh, yeah, I misunderstood you

alpine kindle
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like i respect the maths a level

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it's a pretty good course all things considered

rocky shuttle
#

well, is there any way / are you interested in acceleration?

#

Or maybe just enroll in unversity?

alpine kindle
#

wdym acceleration

#

oh no

#

I don't want to skip years

#

for a myriad of reasons

#

including:

  1. having a-levels is good in case I don't get a degree for whatever reason
  2. i am doing cs and latin in addition to maths: these are subjects that i enjoy and won't get as much time to do once i get to uni
  3. i have a ton of friends in school
  4. it's harder to connect with people 2 years older than you
alpine kindle
rocky shuttle
#

the only downside is then, you have to deal with all the easy stuff, which might bore you

fair mural
#

i mean, being bored because it’s too easy is better than being stressed because it’s too hard

rocky shuttle
#

yap, and there is no need to rush

alpine kindle
#

i really don't want to be "that kid"

#

and i suppose i already sort of am

rocky shuttle
#

Life is too short for math

neat lintel
#

Is there any way to get rid of this dark blue name?

#

I find it hard to read sometimes.

rocky shuttle
#

be very active

neat lintel
#

I'd rather not spend more time on discord than I already do.

deep mango
neat lintel
#

Please do.

#

Thanks.

deep mango
#

just dm modmail if you ever want it removed

neat lintel
#

Got it.

rocky shuttle
#

not very ppl

deep mango
#

it's the "not very ppl" role

static loom
#

lol is that what that role is for?

deep mango
#

yes

neat lintel
#

I guess this role makes me not much of a person.

static loom
#

to "not" the "very active" role haha nice

deep mango
#

i dont understand the name either

rocky shuttle
#

How do you actually get honorable?

static loom
deep mango
#

there is an internal nominations process, there are no set criteria besides the ones listed in #info

haughty apex
#

anyone know why the transitive reduction of a finite direct acyclic graph is unique and a subgraph

slender rover
rocky shuttle
#

𝔇

naive solstice
#

hey guysss

#

is it a or b?

#

im not sure

woven whale
#

e

slender rover
# rocky shuttle 𝔇

i think D too and cant figure out why this website says its wrong, according to it correct answer is B

rocky shuttle
rocky shuttle
slender rover
#

agreed. was curious if anyone else thought B so wouldve asked why and how

bright hill
rocky shuttle
#

How many are there in total rn?

bright hill
#

,whohas onor

fathom swallowBOT
#
Members in ℌonorable (Page 3/3)
===============================
41.  Manan#0640
42.  Rijinaru#5601
43.  Lochverstärker#5585
44.  Plurmorant#1811
45.  Faye#2862
46.  nGroupoid#5061
47.  Element118#2437
48.  Moldilocks#8320
49.  washingbear#1224
50.  Chmonkey#9767
51.  zetamath#3718
52.  Moth#5340
53.  ariana#4631
54.  justAlex#0934
55.  shamrock#0598
56.  det#7067```
bright hill
#

56

#

Huh

#

I thought there'd be more

#

Actually there is more, they just have left the server

#

But only like 5 or 6 or smth

rocky shuttle
#

0.05%

runic holly
#

How do you call recursive sequences that need the 2 previous terms, like the fibonacci one ?

rocky shuttle
runic holly
#

I thought there was a specific name like recursive sequence order 2

rocky shuttle
fervent pebble
#

WQHAT

#

RYCIE WITHOUT BLUE NAME???????????????

#

WTF

rocky shuttle
#

and yellow pfp

#

with hat

thorny grotto
#

anyone want to chill in vc and do some math problems with me?

storm sage
#

someone boosted but didn't want the color

wooden flax
#

@deep mango why did you lose mod

deep mango
wooden flax
#

Np

cold needle
#

Yw

neat lintel
#

ryc is still reserved mod so he went up the ladder

fair mural
#

reserved mod is lower in the role hierarchy than mod

neat frost
#

Ryc is high on copium rn

long matrix
#

dont be rude to ryc

neat frost
neat frost
long matrix
#

which ryc pfp u like better

#

now or shitting penguin

neat frost
#

Now

long matrix
#

@deep mango told u silly billy

deep mango
#

I told YOU that I knew that already doofus

bright hill
reef carbon
#

@swift tide gonna say it here since your channel got closed - stupidity alone is not something to apologize for

eager reef
neat frost
long matrix
devout geode
#

is this just uni math

brittle socket
#

What are you referring to by "this"

ancient flame
#

math enthusiast taking business classes

rocky shuttle
#

$i\cdot\int$

fathom swallowBOT
#

᳄ᮐᮔᮁᮊᮨᮄᮔ᮪

storm sage
fair mural
neat lintel
#

Set theory can predict the future.

torn willow
#

How do you think trading companies work?

azure nymph
#

Philosopher Yogi Berra lol

alpine kindle
neat lintel
#

Some set theory notes. Check my post history.

burnt dune
#

quick question

#

why do we need countable definition

#

if we have denumerable?

#

are there infinite countable sets that are not in bijection with N

#

?

surreal sapphire
#

no

#

because i have never heard the term denumerable

burnt dune
#

denumerable means in bijection with N

#

countable means countable the waay we know it

#

a friend of mine today just told me we should get rid of countable

#

but i thought no waay

#

cuz like

#

surely if you have an injection to N you can fail to have as urjection too

#

so im asking

fair mural
#

countable also means there exists a bijection to N so

surreal sapphire
#

this is a non-issue

#

i never heard the term denumerable

burnt dune
#

okaay

surreal sapphire
#

countable or countably finite/infinite

burnt dune
#

if a set is infinite and cuontable

#

does this mean it has a bijection

#

with it and N

#

no way right?

#

or not no way

#

but no

#

anyone 😦

#

QxQ does not have a bijection to N right?

#

nvm

arctic grove
#

(Products of countable sets are also countable)

#

just read the set chapter in any analysis book for more info on this stuff

burnt dune
#

countable for me means surjection to N

#

but yea

arctic grove
#

thats a weird def for countable?

#

i have always heard countable to mean be in bijection with N or with its subsets

#

i have a feeling denumerable means the same thing as what most people say when they say countable

fair mural
burnt dune
#

injection to N im sorry

alpine kindle
vocal roost
burnt dune
#

lmao but whyu tho

#

{1,2,3} does not have a bijection to N

#

so {1,2,3} is not countable

#

why would u require a bijection

fair mural
#

a bijection to N would mean countably infinite

#

your definition is fine for just countable

fair mural
#

since that includes finite and infinite

#

i know

burnt dune
#

no how

#

if you have two definitions

#

one finite and one countably infinite

#

there are infinite sets that are not countable like R

#

which are neither

#

you need infinite too right

arctic grove
burnt dune
#

yea ur right im respomding to the bijection with N thing

fair mural
#

an injection to N is countably finite OR infinite (or just called countable), a bijection to N is countably infinite

burnt dune
#

doe snot make sense to require it to be a bijection

#

for me

storm sage
storm sage
#

denumerable is not really used

fervent pebble
#

i have been playing some minesweeper lately and the more i play the more i realize just how fucking ridiculous the world record is

#

it's absolutely fucking insane

#

Minesweeper world record on Expert level by Kamil Murański (from 2010/07/03 to 2021/10/14). Clicking speed and precision achieved by using Logitech MX518. You can get it on Amazon: https://amzn.to/2ZuqeA9 (paid link).
Polecam myszkę: https://www.ceneo.pl/85236289#crid=370006&pid=22652

You can watch the analysis of this game in slow motion here:...

▶ Play video
#

this isnt even the wr

#

but i couldnt do this in ten years of constant play

#

it's ridiculous

#

my hs on google easy mode isn't even 10s below it

#

fuck

fervent pebble
lyric totem
#

hey @lucid dust , sorry to disturb you - but, when i tried to solve for a and b,
i obtained a quadratic in terms of b which yielded two solutions
if the question asks for exact values of a and b, how can there be two solutions?

lucid dust
#

If you substitute back and equation hold then it should be fine

devout flame
brittle socket
#

@devout flame Don't advertise your help channel outside your help channel

#

Be patient

ionic quarry
#

if I'm graphing a function where x is the number of days since an event, do I start at zero or are negative days possible

zealous garden
#

Negative days would be before the event

#

You'd have to decide whether or not that's permissible for your application

rocky shuttle
#

But there is actually something called Cauchy's integral formula in complex analysis, which looks like this:

#

$$f(a)=\frac{1}{2\pi i}\oint_{\gamma}\frac{f(z)}{z-a},dz$$

fathom swallowBOT
#

᳄ᮐᮔᮁᮊᮨᮄᮔ᮪

neat lintel
#

can anyone help me sending links of good videos for calculus. from basics

rocky shuttle
neat lintel
#

is it from the basics

#

?

rocky shuttle
#

yes

neat lintel
#

ok thx

modest magnet
#

sus

vocal roost
rocky shuttle
iron osprey
#

only on riemann surfaces

vocal roost
#

hmmm

#

interesting

lament flicker
#

What software/programming language do you guys recommend for creating interactive math tools? For example, I want to create one that shows phase portraits of ODEs in an interactive way (as in you can drag a point on the screen and see how that affects the phase portrait). I thought of matlab or 3b1b's manim for python, are ther other better options?

bright hill
lament flicker
#

I already know C# pretty well so I might consider unity

bright hill
#

I saw Sebastian lague do some really cool stuff using it

river moon
#

well all the times I tried to program some user interface in python the experience was not pleasant, perhaps manim addresses this

#

and I remember when I was just beginning programming c# had an accessible UI designer with lots of basic features built-in

zealous garden
#

I'm working up the motivation to program a 3D graphing calculator in C++ with OpenGL, SDL2, and Klein (a glm replacement that uses geometric algebra)

lament flicker
#

Also damn I just realized that if I want to see trajectories rather than vectors only that'd become like 1000x more computationally expensive

eager crescent
storm sage
lament flicker
burnt dune
#

yoooooo

#

Colimits are so coooooooooooooooooo

#

l

storm sage
#

what's a colimit?

bronze pelican
storm sage
#

LOL

fair mural
#

bruh

wicked plank
#

You guys know any good alternatives?

azure nymph
#

I mean zlib is still up if you know where to look

echo tundra
wicked plank
#

Oh

#

Thanks

brittle socket
leaden torrent
#

pls dont discuss this here

#

fyi

#

discord doesnt like it

tight comet
brave wraith
#

I was thinking of a solution to counter an earthquake.

#

I have an idea that involves balloons, helium, and a house (reference: up)

#

I have researched how many balloons to get the house floating but how do i get it back down :/

#

I was thinking of turning the helium back to liquid but how...

brave wraith
#

Ohhh

#

yes

#

shoot the balloons

#

but that would be kinda pricey since I would need to pop around $100.000 worth of helium

brittle socket
hoary gorge
#

catAngery fbi gonna break in my home to steal my virtual books

zealous garden
#

Reasoning and problem solving

#

You'll also often be working with the same constructs, or at least variants of them

#

Of course your concerns will be different

manic ginkgo
#

It makes you really understand abstraction on another level imo

manic ginkgo
zealous garden
#

I think there are a lot of benefits that you can't really single out

#

The little changes in the way you think and process a problem

#

And in the care you take when you construct your solution

#

Of course there's also just having the wider tool box to choose from

#

With an understanding of the tools instead of copy pasting

manic ginkgo
#

Yeah the other things I noticed was it made my thinking and statements way more precise, understand why that matters and how to structure things better / more efficiently

#

So I’d hope that if you get better with proofs you’d also get better with writing programs 😛

neat lintel
steady portal
#

I wonder how many days I can procrastinate

#

And end up giving up on math

fading zealot
#

Cuboctahedrons (Archimedean solid with 14 faces) seen in Taipei Confucian Temple

#

This is an underrated shape

final fossil
#

Any us or uk or Australia student?

#

I need help

#

Cuz name cheap offer free domain name to thos students

#

And i really need a domain name!

versed geode
#

t!selfrole remove

long matrix
#

mwow

#

@small wave whats is this

#

@neat frost is this u

outer dew
tawdry falcon
patent matrix
#

Hello

#

I lost the channel where I got my answer. Is there a way I can get redirected?

neat frost
fading zealot
patent matrix
long matrix
neat frost
#

I wanted to stream my computer but the audio quality on it is shit, so I wanted to also connect through my tablet for audio

neat frost
obtuse heart
#

lain zi ler

#

poopoofirc

long matrix
neat frost
#

When I have Linux

long matrix
#

meow

lofty wagon
#

How many ways can we climb a staircase with n steps if we can take either 1 or 2 steps at a time?
i kinda know it, but i don't understand the proof to it. please help

brittle socket
#

Yay I drew my first commutative diagram!

#

In latex

bright hill
#

Can't believe you use that filth

zealous garden
#

I have a laptop with a throwaway hard drive in it rn that has windows installed

#

the linux drive is sitting in a dock on my desk

#

I need Windows for some certification tests so I'm forced

bright hill
#

Real OGS would use a VM

zealous garden
#

I would

#

that doesn't work

#

I guess if I was willing to do some research and put in the work I might be able to throw together a windows qemu install that could trick the software that checks if it's a VM

#

but that's a lot of work for a "maybe"

neat frost
bright hill
#

You got a Windows machine...

#

That's all I needed to know.

deep mango
#

Windows is a lot better than Linux

alpine kindle
inland raft
#

why isnt ryc a mod anymore?

brittle socket
inland raft
#

?

brittle socket
#

Still has the reserve mod role

inland raft
#

but thats not mod

brittle socket
#

Also, he said that he's just taking a break

brittle socket
inland raft
#

ok

zealous garden
#

based ryc

brittle socket
neat lintel
#

hi

#

i have a list

woven whale
#

yes

neat lintel
#

and i wanna check which of the numbers in that list mod 3 returns 0 (the first match)

frigid matrix
#

you are forgetting conditionals i think

#

find x mod 3 you might want

woven whale
#
find (\x -> x `mod` 3 == 0) list
#

mod returns a specific value

neat lintel
#

what does the \x mean?

woven whale
#

lambda

neat lintel
#

ah ok

woven whale
#

it's like a function that takes in a value x

neat lintel
#

very cool

woven whale
#

when you dohaskell `mod` 3 it's essentially```haskell
\x -> x mod 3

frigid matrix
#

why cant she do find (x ‘mod’ 3) list

woven whale
frigid matrix
#

yes

woven whale
#

yes

#

the find argument must be a predicate

frigid matrix
#

if the value is nonzero its false

woven whale
#

i.e. return a bool

frigid matrix
#

oh

woven whale
#

booleans aren't numbers in haskell

frigid matrix
#

ok

woven whale
#

I haven't done haskell in like at least two years lmao

#

but bool is defined like this I think

frigid matrix
#

why did you do haskell at all

woven whale
#

type Bool = True | False

#

or something like that

woven whale
#

so I decided to learn it

frigid matrix
#

oh cool

neat lintel
#

based

frigid matrix
#

what do you do now

woven whale
#

type is type alias

#

it's

#

data Bool = True | False

neat lintel
#

where did u learn it illum

woven whale
neat lintel
#

i am just reading the documentation 💀

#

i am exactly reading this

frigid matrix
#

i used that lol

neat lintel
#
  • Hoogle
woven whale
#

don't have time for programming anymore sadly

frigid matrix
#

math like undergrad?

woven whale
#

yes

frigid matrix
#

this is sad

#

do you think ull ever use haskell again

woven whale
#

I used to do AoC in haskell

frigid matrix
#

aoc?

#

art of code?

woven whale
#

advent of code

frigid matrix
#

oh

neat lintel
#

lol i am on linux and got a windows-like scamming ad 🥱

fading surge
#

hi

#

ok, I will send the design document, the rulebook for the game, so you understand what I am talking about

frigid matrix
#

ok

fading surge
#

how is it @frigid matrix?

frigid matrix
#

i dont completely understand novae reactions

#

like when do star cards detonate

fading surge
#

ok, for instance you place Planets next to the Star, with directions facing the Star, if the total Mass Points of everything pointing at the Star is equal to or higher than the Mass Points of the Star, the Star will go Nova

frigid matrix
#

oh ok

#

the mass point of the star add towards your total mass points

#

and the star map gets reset?

fading surge
#

Planet vs Star > Deduction > Nova
Planet vs Planet >Addition > Attraction
Star vs Star > Deduction > Supernova

#

no, you collect the cards that went Nova, and the total Mass Points is like your Victory Points

frigid matrix
#

so ideally you want all planet cards

fading surge
#

no, you want Stars

#

Stars is what gives you points

#

actually both

#

you need Stars and Planets

frigid matrix
#

you said planet vs planet implies addition?

fading surge
#

yes

#

planets with arrows pointing at each other, add up their Mass Points

frigid matrix
#

oh

fading surge
#

so you understand?

#

there are still certain quirks and kinks that needs fixing

#

but that's the general idea

#

are you there bro?

#

so you interested in working with me on this?

#

can you work out how many configurations are possible, keeping in mind repeated orders based on rotation?

frigid matrix
#

im here lol

fading surge
#

ok great

#

so wanna work with me?

#

I need a mathematical mind

frigid matrix
#

i do not want to make a commitment

fading surge
#

mine is more oriented towards linguistic

#

I see

#

what if I pay you?

frigid matrix
#

but i can help with direct math questions

fading surge
#

I see

frigid matrix
#

brb

fading surge
#

ok nvm

frigid matrix
#

i would do for free but not commitment

fading surge
#

ok

#

what commitment?

frigid matrix
#

let me rephrase. if you ask questions here i will try to answer them but I won’t set aside time to answer them/be committed to a project

fading surge
#

ok

#

so wait, you looked at the rulebook?

frigid matrix
#

yeah i read it for most part

#

but mechanics are slightly unclear

fading surge
#

what is unclear?

#

ask me anything

frigid matrix
#

id like to see a play through of the game maybe

fading surge
#

I see

#

I got some questions
there are two Decks, the Star Deck and the Constellation Deck
can you draw from both at the same time at once?
and when your turn comes, can you pass?
just draw without putting anything down?

#

how about if both players pass consecutively, the next player must place a card?

#

You may either draw up to 2 Cards from the Star Deck or the Constellation Deck at the end of a Round, which is when both Players take their Turn in sequential order. Constellation Effects last for one Round. You may also choose to pass from placing a Card down, but if both players pass consecutively, the next player has to place a Card down.

#

is this understood @frigid matrix

frigid matrix
#

you cant draw from at once

#

i read it said either 1 constellation or 2 star

fading surge
#

ok

#

good idea

frigid matrix
#

wait you said this

#

or are you still in designing stage of rules?

fading surge
#

there are some kinks

#

there always are

#

at some level

#

but the game is more or less written down

frigid matrix
#

are you trying to make the game as balanced as possible

fading surge
#

yes

#

exactly

frigid matrix
#

because its a good idea to have a google sheets or something similar

fading surge
#

can I ask how many permutations can there be?

#

can we talk in DM?

#

if not it is ok

frigid matrix
#

yeah but atm my attention is sort of split so it might take me some time to respond as you noticed. sorry about this

fading surge
#

np

#

you there?

frigid matrix
#

sorta just ask the question

#

how many permutations of what

fading surge
#

there are 20 Stars, 14 Asteroids, 2 Moons, 24 Planets

#

for a grand total of 60 Cards

#

how many permutations are possible?

#

given rotation orientation?

#

@frigid matrix

#

is it ok if I ping you at times?

frigid matrix
#

yeah i dont mind

fading surge
#

ok cool

#

so I got 60 cards

#

what's the number of unique permutations?

#

8 directions

#

some 1, some 2, some 3, some 4, some 5, some 6, some 7, some 8

frigid matrix
#

yeah

fading surge
#

3 is 14

#

8 is 1

#

7 is 2

#

1 is 8

frigid matrix
#

i guess you are meaning to ask about combinations

fading surge
#

yea

#

actually permutations, not combinations

frigid matrix
#

So are you asking given a star card with 1<=x<=8 directions how many unique star cards can you have?

#

Okay actually you arent asking that

fading surge
#

maybe it is easier to vc?

frigid matrix
#

How many cards can you have per hand

#

not today sry no vc

fading surge
#

you start with 5 cards

frigid matrix
#

okay

#

you are saying with 5 cards how many what?

fading surge
#

erm

#

you don't get it?

frigid matrix
#

im not sure what you want to count

fading surge
#

there are 60 cards in total, 14 Asteroids, 2 Moons, 24 Planets, 20 Stars

frigid matrix
#

yes

fading surge
#

I want them all unique if possible

frigid matrix
#

ok

#

all of these card types have same number of gravity lines?

#

when you say unique I think you mean unique gravity line directions

#

Like if you have a card type with N gravity lines that can point in 8 directions then we have that you can have 8chooseN unique cards

fading surge
#

well, they have different number of arrows

frigid matrix
#

So some asteroid type cards have a different number of gravity lines/arrows?

fading surge
#

no, all the 14 Asteroid Cards have the same number of Gravity Lines

frigid matrix
#

Okay

fading surge
#

that's why there are 14 of them

#

but the Planets and Stars, that's the tricky one

#

Moons(MP2): Reflection – Turn one orthogonally or diagonally adjacent Card 90 degrees. You may activate this Ability anytime instead of placing a Card.
Pluto(MP3): Underworld – Turn one orthogonally or diagonally adjacent Card upside down once a Game.
Mercury(MP4): Quicksilver – May Move Mercury one Space in any direction once a Game.
Mars(MP4): God of War – Discard Planet Cards equal to its Mass Points or less, when placed next to them once a Game.
Venus(MP5): Morning Star – Mass Points with Gravity Lines directed at Venus, with its own Gravity Lines directed back, get redirected back to the Source.
Earth(MP5): The Blue Planet - Reclaim Planetary Bodies of Mass Points equal to Earth's MP, from your Opponent.
Neptune(MP6): Deep Freeze – Cause the Opponent to Miss a Turn once a Game.
Uranus(MP6):
Saturn(MP7):
Jupiter(MP8):
Varuna(MP3)
Ceres(MP3)
Sedna(MP3)
Quaoar(MP3)
Makemake(MP3)
Haumea(MP3)
Eris(MP3)
Kepler-37b(MP4)
Trappist-1e(MP4)
55 Cancri e(MP5)
Gliese 504 b(MP7)
TrES-2b(MP7)
WASP-17b(MP8)
GQ Lupi b(MP9)
HD 100546b(MP10)

#

2MASS J0523-1403(MP8)
Trappist 1(MP9)
Proxima Centauri(MP10)
Barnard's Star(MP11)
Teide 1(MP12)
HD 100546b(MP13)
Sun(MP14): Sunburst – Once a Game, the Sun has Gravity Lines in all directions, if triggered from another Card at an unopposed angle.
Sirius A(MP15)
Pollux(MP16)
Arcturus(MP17)
Aldebaran(MP18)
Rigel(MP19)
Deneb(MP20)
Pistol Star(MP21)
Antares(MP22)
Betelgeuse(MP23)
Mu Cephei(MP24)
VY Canis Majoris(MP25)
UY Scuti(MP26)
Stephenson 2-18(MP27)

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you there? what do you suggest each orientation should be?

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how many permutations are there of 2 Arrows in unique configurations?

frigid matrix
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arrows are gravity lines right?

fading surge
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yes

frigid matrix
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8 choose 2

fading surge
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so how many?

frigid matrix
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its just this formula really

fading surge
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I see

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so how many?

frigid matrix
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28 my calculator tells me

fading surge
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I see

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hmm

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is it possible for you to help me figure out the Gravity Lines of the 20 Stars and 24 Planets, together with the two Moons?

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the two Moons are Moon and Charon

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is it possible?

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the largest Star of 27 Mass Points will have arrows pointing in all directions

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how about for Supernova, if you use a Star to initiate the Nova, that Star is not counted, you do not get it as Victory Points?

bright hill
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Lies!

azure nymph
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It's great at letting me kick the update can down the road until it decides to update while I'm working on my problem set for class that I forgot to save so I lose 40 minutes of progress

fading surge
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@frigid matrix hi, you back yet?

frigid matrix
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yea

fading surge
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so what do you suggest?

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how many permutations are there?

frigid matrix
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moons have 8 gravity lines?

fading surge
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all have 8

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as in, 8 possible

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just whether 1 to 8

frigid matrix
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how many actual gravity lines do moons have

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or does it vary

fading surge
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hmm, no idea at the moment

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there are only 2 Moons

frigid matrix
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like you said aseteroids had 3 out of 8

fading surge
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The Moon and Charon

frigid matrix
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If there are only two moons and they are powerful cards maybe give them less gravity lines?

fading surge
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they aren't powerful

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they are MP2

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they have Reflection though

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this game is the toughest game I ever had to design

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I faced a similar challenge with my Star Wars Lightsaber duelling board game

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but this is way harder

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what do you suggest? based on your mathematical ability and talent?

frigid matrix
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im not sure i have decision expertise for designing a game

fading surge
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np, we work together

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I am a game designer, so I have a knack for it in the first place

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I just need a little help and nudge

fading surge
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@frigid matrix so how?

covert siren
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Has anyone tried paperlike screen protector for the Ipad?
Thinking of switching over to taking notes, etc. on my Ipad but it's quite slippery so I saw paperlike was an option.
Has anyone used it for writing math problems, if so is it worth it? (Just finding a bunch of sponsored videos on youtube, want an unbiased opinion)

sterile yoke
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anyone know how to use excel

covert siren
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Thanks, will take a look at it 🙂

hushed pagoda
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is anybody familiar with mla citation here?

storm sage
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check purdue owl, they're such a good resource

brittle socket
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Feels nice when you make a link between two concepts and you are correct :D

hybrid lotus
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anyone takes calculus 1 at university?

woven whale
fading surge
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@frigid matrix hi!

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is there an accurate way of considering where the directions point towards for every Mass Point?

arctic grove
proud olive
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Copying what?

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Is it something Linux can copy that windows can't?

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Linux can copy money??

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Keep copying

arctic grove
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coping

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not copying

brittle socket
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Hi ShyShuu

neat lintel
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if earth revolves around the sun, does the sun revolve around something of larger mass?

neat frost
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Indeed

neat lintel
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what is it

neat frost
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The galaxy spins or whatever

neat lintel
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woah

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does that mean the entire solar system shifts and moves in space?

neat frost
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Yes

neat lintel
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so what does it orbit?

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the center of the galaxy

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or is there something smaller than that that's a mid-point

neat frost
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Yeah something like that iirc. I only know what I’ve read in popsci BS, so I don’t know shit about physics, but pretty sure it orbits the massive black hole in the middle of the galaxy

brittle socket
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In the milky way gal its sagitaraus A* or smt I think

neat lintel
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interesting stuff

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thank you

zealous garden
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Yes

brittle socket
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np : )

zealous garden
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Galaxies have massive blackholes at the center, some even have quasars

brittle socket
zealous garden
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I'm not sure if it's strictly every galaxy

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I assume it is

neat lintel
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man

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I'm very tired of factoring problems in my math class

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it's very tedious

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$a^3-b^3=(a-b)(a^2+ab+b^2)$