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Jeff Strom
  • Member for 12 years, 3 months
  • Last seen more than a week ago
102 votes

nontrivial theorems with trivial proofs

97 votes

Why do we teach calculus students the derivative as a limit?

69 votes

Can a subset of the plane have nontrivial $H_2$ or $\pi_2$?

54 votes

Can a mathematical definition be wrong?

39 votes

What are some noteworthy "mic-drop" moments in math?

36 votes

In a topological space if there exists a loop that cannot be contracted to a point does there exist a simple loop that cannot be contracted also?

33 votes
Accepted

Is every real n-manifold isomorphic to a quotient of $\mathbb{R}^n$?

32 votes
Accepted

Suspension of a topological space

30 votes

The role of the mean value theorem (MVT) in first-year calculus

28 votes

Main statement as theorem or corollary

27 votes
Accepted

Interesting Calculus Questions/Exercises

25 votes
Accepted

Image of a map on cohomology rings

25 votes

Why is it so hard to compute $\pi_n(S^n)$?

24 votes
Accepted

Homotopy equivalent Postnikov sections but not homotopy equivalent

21 votes
Accepted

Whitehead theorem for cohomotopy

20 votes
Accepted

Divisibility in the homotopy groups of spheres?

19 votes

Advantages of working with CW complexes/spaces over Kan complexes/simplicial sets?

17 votes

An abstract nonsense proof of the Hurewicz theorem

16 votes

The most outrageous (or ridiculous) conjectures in mathematics

14 votes

Teaching Steenrod Operations

13 votes
Accepted

In a fibration, can a deformation retraction of the base be lifted to the total space?

13 votes

Proof synopsis collection

13 votes

What is the intuition behind the Freudenthal suspension theorem?

12 votes

Why should one still teach Riemann integration?

12 votes

Why does homotopy behave well with respect to fibrations and homology with respect to cofibrations?

12 votes

Counterexamples in algebraic topology?

12 votes

Categories First Or Categories Last In Basic Algebra?

9 votes

when cup product is a zero homomorphism

9 votes

Homotopic maps out of cofibration sequences

9 votes
Accepted

continuous images of open intervals

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