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Oct
2
awarded  Enlightened
Oct
2
awarded  Nice Answer
Sep
30
awarded  Explainer
Sep
24
awarded  Autobiographer
Sep
23
comment Does the number pi have any significance besides being the ratio of a circle's diameter to its circumference?
@Ant: My comment was a reply to asmeurer's speculation that it had to do with "angles and the 2D lattice" -- my comment was not a reply to anything in this (damiano's) answer.
Sep
22
comment The myth of no prime formula?
You ignored the word "useful" in Tao's comment: here, "useful" means something that allows us to compute the $n$th prime significantly faster than what follows straightforwardly from its definintion.
Sep
22
comment Why doesn't the definition of the interior of a set depend on the dimension of the set
The definition of interior does depend on the space you're working in (in exactly the ways you mentioned). What definition have you seen?
Sep
21
comment Is there a known mathematical equation to find the nth prime?
Why the downvote?
Sep
20
awarded  Revival
Sep
20
comment Look at the following infinite sequence: 1, 10, 100, 1000, 10000, . . ..
@Olcayto‌: Any number and any sequence. :-)
Sep
17
awarded  Good Answer
Aug
16
comment Is '10' a magical number or I am missing something?
@JoSo: You may notice that I always used "base 1" in quotes — of course it's not one of the general class of "base n" representations, but there does exist such a thing as the unary numeral system: en.wikipedia.org/wiki/Unary_numeral_system. I feel I'm repeating the comment I made to user dhasanen above. In the unary numeral system, you can use any symbol you like (either 0 or 1 or X or whatever), and correspondingly 0000 or 1111 or XXXX would represent the number 4.
Aug
9
revised Where did $-4x$ come from?
removed stray +4
Aug
9
revised Where did $-4x$ come from?
removed stray +4
Aug
4
awarded  Good Answer
Jul
29
comment Are there more examples of functional equations which are also valid for the identity map?
@Isomorphism: Feel free to edit the question (you can mention Semiclassical in your edit) -- improving the question to make it clearer (and answerable) is very much encouraged, not frowned upon.
Jul
27
awarded  Yearling
Jul
27
comment Are there more examples of functional equations which are also valid for the identity map?
Well, $\sin$ is not a homomorphism, and $\sin (A^2) \neq \sin^2 (A)$ (which stands for $(\sin A)^2$), and the OP explicitly excludes homomorphisms as trivial, so... yeah it's not clear what "preserve" means.
Jul
25
reviewed Reject suggested edit on On the Origin and Precise Definition of the Term 'Surd'
Jul
21
comment Is $.999999999… = 1$?
@ElazarLeibovich: Yes, that's what I was pointing out. :-)