As of May 31, 2023, we have updated our Code of Conduct.
Mathematics
Noah Schweber's user avatar
Noah Schweber's user avatar
Noah Schweber's user avatar
Noah Schweber
  • Member for 11 years, 2 months
  • Last seen this week
Profile Activity

5,066 Answers

Score Activity Newest
223 votes
Accepted

Why is it important for a matrix to be square?

123 votes

Where are the axioms?

109 votes
Accepted

Why are There No "Triernions" (3-dimensional analogue of complex numbers / quaternions)?

80 votes

Is there a bijection between the reals and naturals?

79 votes

Why write ten as $10$ and not as $00$

78 votes

Is mathematics just a bunch of nested empty sets?

74 votes

What's wrong with this reasoning that $\frac{\infty}{\infty}=0$?

69 votes

Can you prove that proof-by-induction is invalid for the real interval [0, 1]?

63 votes
Accepted

Avoiding proof by induction

63 votes
Accepted

Hilbert's hotel: why can't I repeat it infinitely many times?

59 votes
Accepted

Are there any Turing-undecidable problems whose undecidability is independent of the Halting problem?

59 votes
Accepted

Why do people accept the axiom of choice given the well ordering principle?

53 votes
Accepted

Set builder notation: Colon or Vertical Line

52 votes
Accepted

What is meant, exactly, by nonrepeating when talking about irrational numbers?

52 votes
Accepted

Why do we define the modulus of a complex number as we do?

51 votes
Accepted

Does the existence of a mathematical object imply that it is possible to construct the object?

50 votes
Accepted

Difference between provability and truth of Goodstein's theorem

49 votes
Accepted

Is there a model of ZFC inside which ZFC does not have a model?

48 votes

Implication in mathematics - How can A imply B when A is False?

47 votes
Accepted

Is there a function $f:{\mathbb N}\to{\mathbb N}$ that is neither injective nor surjective?

45 votes
Accepted

Does there exist an operation that could turn the set of all negative real numbers into an abelian group?

45 votes
Accepted

Are the rationals on a unit circle dense?

45 votes

Why aren't all square roots irrational?

43 votes
Accepted

Opposite of Fermat's Last Theorem?

42 votes
Accepted

Is indefinite integration suspect?

42 votes
Accepted

Is there any uncountably infinite set that does not generate the reals?

41 votes
Accepted

Is aleph-$0$ a natural number?

40 votes
Accepted

Does the unique existential quantifier commute with the existential quantifier?

40 votes

What's between the finite and the infinite?

40 votes
Accepted

How long can proofs be?

1
2 3 4 5
…
169

Your privacy

By clicking “Accept all cookies”, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy.