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Clement Yung

Singapore

Pure mathematics undergraduate hoping to enter academia.

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Top Questions
18 votes

Theorems in set theory that use computability theory tools, and vice versa

set-theory computability-theory asked Apr 18 at 1:55
mathoverflow.net

14 votes

Can ($X^I$, product topology) and ($X^I$, box topology) be homeomorphic for some nontrivial $X$ and infinite $I$?

gn.general-topology asked Oct 2, 2022 at 15:38
mathoverflow.net

14 votes

Is "There exists an unbounded non-measurable set but no bounded non-measurable set" consistent with $\mathsf{ZF}$?

set-theory lo.logic measure-theory model-theory asked May 18, 2021 at 12:46
mathoverflow.net

11 votes

Can every functional equation be solved or proved unsolvable?

logic functional-equations asked Dec 1, 2021 at 11:21
math.stackexchange.com

9 votes

Why is choice needed in Ellis' Lemma?

semigroups-and-monoids axiom-of-choice topological-semigroups-and-monoids asked Feb 28, 2022 at 5:26
mathoverflow.net

7 votes

Models with fixed cardinality of non-Lebesgue measurable sets

set-theory lo.logic measure-theory model-theory asked May 15, 2021 at 6:23
mathoverflow.net

6 votes

Properties of Jech's hierarchy of stationary sets (Exercise 8.13, 8.14 of Jech)

set-theory lo.logic infinite-combinatorics asked Apr 26, 2022 at 7:38
mathoverflow.net

6 votes

Renaming an environment then replace the original environment

environments asked Jul 13, 2021 at 9:04
tex.stackexchange.com

6 votes

Unbounded set in $V[G]$ has an unbounded subset in $V$?

set-theory forcing asked Aug 18, 2021 at 15:11
math.stackexchange.com

6 votes

Ramsey ultrafilters on partial order

set-theory ultrafilters ramsey-theory asked Oct 20, 2021 at 14:27
mathoverflow.net

1 2

Top Answers
15
Proving that $f'(x)\le f(x), \forall x\in \mathbb{R}$
math.stackexchange.com

9
$\int_0^1f(x) dx =0$, $\int_0^1xf(x) dx =0$. How to show that f has at least two zeros?
math.stackexchange.com

8
Why does Stolz- Cesaro fail to evaluate the limit of $\dfrac{n + n^2 + n^3 + n^4 + \ldots + n^n}{1^n + 2^n + 3^n + 4^n + \ldots +n^n}$,
math.stackexchange.com

7
Proving that the set of rational numbers between 0 and 1 is disconnected.
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7
In which case these integrals are equal?
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7
How can I turn a $0^0$ form into a $\frac{\infty}{\infty}$ or $\frac{0}{0}$ form?
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6
How can we show that the given sequence converges to $\frac{5}{6}$?
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6
Convergence of a particular infinite series
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6
show that $x_1^2+x_2^2+\cdots+x_{2020}^2\geqslant x_1x_2+x_2x_3+\cdots+x_{2020}x_1$
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6
Find $a_n:a_{n+1}$ if $a_n=\int_0^{\pi/2}\cos^nx.\cos nx.dx$
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6
Differentiability of $\cos \lvert x\rvert$
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6
Let $a$ and $b$ be elements of odd order in a finite group. Show that $a^2$ and $b^2$ commute if and only if $a$ and $b$ commute.
math.stackexchange.com

6
Models with fixed cardinality of non-Lebesgue measurable sets
mathoverflow.net

6
If you divide two equations by each other and you get a valid equation, does that necessarily mean original equations are also valid?
math.stackexchange.com

6
The definition of cofinality of an ordinal
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6
In what sense are proofs that rely on the Law of the Excluded Middle really proofs?
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5
Prove the surjectivity of $f(r,m)$ from $\mathbb{Z^{+}} \times \mathbb{N} \rightarrow 2\mathbb{N}+1$
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5
Calculate this limit : $\lim_{n\to\infty} \frac{(n^n+1)(n+1)}{(n+1)^{n+1}+1}$
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5
what is $\sum_{n=1}^\infty\frac{1}{n!\log n!}$
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5
Find the Maxima of $g(x)= xe^{x^{2}} + e^{-x^{2}}$ in $[0,1]$
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5
What is the superior limit of this sequence?
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