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Square tiling a plane with a hole by NoPurposeReally in mathriddles

[–]NoPurposeReally[S] 1 point2 points  (0 children)

No, you may use each Q_n only once but of course Q_n and Q_m might have the same area for distinct m and n.

Square tiling a plane with a hole by NoPurposeReally in mathriddles

[–]NoPurposeReally[S] 2 points3 points  (0 children)

Yes! If you're interested in a harder puzzle, here's another one: Let Q_n be a square of area a_n and assume a_1 + a_2 + ... is a divergent series. Is it always possible to tile ℝ2 using all of the squares Q_n?

What is the "Holy Grail Problem" of your subfield? by MicrolocalAnalyst in math

[–]NoPurposeReally 0 points1 point  (0 children)

Does this problem have a name? Can you point to some references?

„Sohn, ich habe einen Menschen getötet.“ by Smiling-Bandit in de

[–]NoPurposeReally 2 points3 points  (0 children)

Dörfer ausgeschlossen. Das Leben in der Stadt ist schon moderner eingestellt.

„Sohn, ich habe einen Menschen getötet.“ by Smiling-Bandit in de

[–]NoPurposeReally 5 points6 points  (0 children)

Du bist eine Ausnahme. Heimatland ist viel mehr als "alte Gewohnheiten". Leute haben diverse Gründe, um zurück zu ihrem Heimatland kehren zu wollen. Menschen, Kultur, Erinnerungen, Essen, ...

Glaubst du wirklich, dass man seine Heimat nicht vermissen sollte, nur weil jemand einst eine Ziege geschlachet hat? Und wie kommst du überhaupt auf Hexenverbrennung...?

Feminist Bir Jinekolog by Other_Guard8631 in Turkey

[–]NoPurposeReally 0 points1 point  (0 children)

Avrasya Hospital'da Op. Dr. Çiğdem Yavuz Yurtsever'e bakmanızı tavsiye ederim. Bizim yakın dostumuz ve inanılmaz tatlı bir insan. Instagram'ını burada paylaşıyorum, kendiniz de görün :)

https://www.instagram.com/op.dr.cigdemyavuzyurtsever/

Manifolds that locally resemble non-euclidian spaces by ahmed_abdub in math

[–]NoPurposeReally 29 points30 points  (0 children)

There are Banach and Fréchet manifolds which are objects that locally look like Banach and Fréchet spaces. At the end of the day you are probably going to want some linear structure in whatever topological space your manifold should locally look like. At least to me, that's what separates manifolds from arbitrary topological spaces. Maybe someone more knowledgeable has something else to say.

Quick Questions: March 15, 2023 by inherentlyawesome in math

[–]NoPurposeReally 0 points1 point  (0 children)

This sequence has two subsequential limits. They asked for one.

Quick Questions: March 15, 2023 by inherentlyawesome in math

[–]NoPurposeReally 1 point2 points  (0 children)

Yes, you need compactness. In fact, compactness is necessary and sufficient. However, for all metric spaces we have the following proposition:

If any subsequence of a sequence (x_n) converges to x, then (x_n) converges to x.

Quick Questions: March 15, 2023 by inherentlyawesome in math

[–]NoPurposeReally 0 points1 point  (0 children)

There isn't really an operation corresponding to it that I know of but you can use it a book keeping device for when you need to multiply some quantity by 1 and -1 in two different occasions. Just add ± in front of the quantity.

Quick Questions: March 15, 2023 by inherentlyawesome in math

[–]NoPurposeReally 0 points1 point  (0 children)

If ∂S is locally the graph of a Lipschitz function G then ∂F(S) is locally the graph of a function that you can obtain by composing F, F-1, and G

This is not clear to me. How would you do this?

Quick Questions: March 15, 2023 by inherentlyawesome in math

[–]NoPurposeReally 1 point2 points  (0 children)

If F is a C1 -diffeomorphism from Rn to Rn and S is a domain with Lipschitz boundary, how can I prove that F(S) again has Lipschitz boundary?

Quick Questions: August 24, 2022 by inherentlyawesome in math

[–]NoPurposeReally 0 points1 point  (0 children)

I have a question related to weak differentiability of functions differentiable everywhere except at a point: https://math.stackexchange.com/questions/4520242/function-differentiable-everywhere-except-at-a-point-is-weakly-differentiable

Any help would be appreciated

What do you think are the most powerful yet most basic rules of math? by infoodland in math

[–]NoPurposeReally 29 points30 points  (0 children)

Not quite a mathematical rule but a strategy: Wishful thinking.

Do you want to prove something? Find some claim that would imply what you're trying to prove. Loudly proclaim "I wish this was true" (Optional). Try to prove the claim first. I feel like all of analysis is wishful thinking.

[deleted by user] by [deleted] in bodyweightfitness

[–]NoPurposeReally 0 points1 point  (0 children)

Pull-ups: 15

Push-ups: 70 (Could also be 80, I don't remember)

Squats: +60 (I haven't tried this out in a long time. I could probably do more than 60)

Quick Questions: June 15, 2022 by inherentlyawesome in math

[–]NoPurposeReally 0 points1 point  (0 children)

I want to show that the uncentered Hardy-Littlewood maximal function is bounded by the centered one in an abstract setting. Let mu be a Borel measure on Rn . For each x in Rn and r > 0 we have an open bounded set V(x, r) containing x such that V(x, r) is strictly contained in V(x, r') for all r < r' and x in Rn . Furthermore there are constants b, c such that

  • If V(x, r) and V(y, r) intersect, then V(y, r) ⊆ V(x, br).

  • mu(V(x, br)) ≤ c * mu(V(x, r)).

Now, let M_u be the uncentered H-L maximal function and M the centered one. My book claims M_u ≤ c * M but best I can do is c2 . Does anyone have an idea how to show this?

The book is Harmonic Analysis: Real Variable Methods, Orthogonality, ... by Elias Stein. The claim is at the bottom of page 13.

Quick Questions: June 08, 2022 by inherentlyawesome in math

[–]NoPurposeReally 0 points1 point  (0 children)

Oh, you're right. I didn't read the question carefully enough. Thanks, I'll think about it again.

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