José Carlos Santos

Porto, Portugal

http://www.fc.up.pt/mp/jcsantos/

I am a mathematician who works at the University of Porto (Portugal). My PhD, on Representation Theory, was obtained at the Université Paris — Denis Diderot, in 1996.

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Unexpected examples of natural logarithm

soft-question logarithms big-list asked Jul 3 '17 at 13:07

math.stackexchange.com

38 votes

Proving $\left(1-\frac13+\frac15-\frac17+\cdots\right)^2=\frac38\left(\frac1{1^2}+\frac1{2^2}+\frac1{3^2}+\frac1{4^2}+\cdots\right)$

real-analysis sequences-and-series summation asked Oct 2 '17 at 10:17

math.stackexchange.com

22 votes

Is every matrix conjugate to its transpose in a continuous way?

linear-algebra matrices continuity asked Dec 14 '18 at 10:03

math.stackexchange.com

19 votes

Did Emanuel Lasker write a book declaring that Germany had to win World War I if civilization were to be saved?

world-war-one germany book biography asked Sep 12 '18 at 9:48

history.stackexchange.com

14 votes

Egyptian fractions with very large denominators

reference-request algorithms egyptian-fractions asked Jul 20 '18 at 9:34

math.stackexchange.com

14 votes

Constructing the reals from the integers

reference-request real-numbers asked Aug 25 '17 at 14:41

math.stackexchange.com

14 votes

Was the insanity of kings used as an argument against monarchy?

monarchy republic asked Apr 9 at 10:09

history.stackexchange.com

12 votes

Why those who dislike the fact that the reals are uncountable always attack Cantor's diagonal proof?

soft-question infinity asked Aug 19 '17 at 14:50

math.stackexchange.com

11 votes

Are there any cases of rewarding an enemy commander for sparing a city from looting?

warfare loot asked Feb 6 '18 at 23:32

history.stackexchange.com

11 votes

Is there evidence that the annual pilgrimage to Mecca facilitated cultural exchanges?

middle-ages cultural-history islamic-history asked Jul 12 '18 at 12:31

history.stackexchange.com

Top Answers

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José Carlos Santos

Unexpected examples of natural logarithm

Proving $\left(1-\frac13+\frac15-\frac17+\cdots\right)^2=\frac38\left(\frac1{1^2}+\frac1{2^2}+\frac1{3^2}+\frac1{4^2}+\cdots\right)$

Is every matrix conjugate to its transpose in a continuous way?

Did Emanuel Lasker write a book declaring that Germany had to win World War I if civilization were to be saved?

Egyptian fractions with very large denominators

Constructing the reals from the integers

Was the insanity of kings used as an argument against monarchy?

Why those who dislike the fact that the reals are uncountable always attack Cantor's diagonal proof?

Are there any cases of rewarding an enemy commander for sparing a city from looting?

Is there evidence that the annual pilgrimage to Mecca facilitated cultural exchanges?