5,355 reputation
12146
bio website sbseminar.wordpress.com
location New York, NY
age 34
visits member for 4 years, 1 month
seen 11 hours ago

I'm an assistant professor in mathematics at Indiana and an early adopter of Math Overflow. I was the first user at mathematics.SE.


14h
reviewed Close correlation coefficient between ordinal and binary variables spss or stata
14h
reviewed Close What is the difference quotient for the function?
14h
reviewed Close Show that the set $K=[0,1]$ is compact in $\Bbb{R}$
14h
reviewed Close gcd and lcm from prime factorization proof
14h
reviewed Close Does $\sum_B p(L|B)p(B|G) = \sum_B p(L,B |G) = p(L|G)?$
14h
reviewed Close Injective hull of $\mathbb{ Z}_n$
1d
reviewed Close How can i resolve this limit without L'Hopital's Rule?
1d
reviewed Leave Open How does $A_n$ look in Aut$(X)$?
1d
reviewed Close distribution of books among students
1d
reviewed Close continuous function-constant
1d
reviewed Close Random walk probability
1d
reviewed Close Program for writing a Bachelor Thesis.
Aug
7
comment Is $.999999999… = 1$?
@Matteo: That's a great way of putting it. Of course it's equivalent to the other definition, but if you only want to talk about infinite decimals you're right that your definition is easier.
Aug
4
reviewed Close Cardinality of the real numbers
Aug
4
reviewed Close Orthogonalization of two Vectors
Jul
20
awarded  Yearling
May
17
reviewed Reject suggested edit on Is $.999999999… = 1$?
May
9
awarded  Nice Answer
Mar
10
comment Proving that $\dim(\mathrm{span}({I_n,A,A^2,…})) \leq n$
Now that the typo is sorted out, if you have a math question that you still need answered then you should edit the question to fix the typos and get it reopened.
Feb
28
comment Topology - interval homeomorphic to another interval
@SKA: For bounded intervals you're going to approach is similarly to the way you approached the other ones: find an explicit continuous function going each way. In this case you can use pretty simple functions. As for why [0,1] and $(-\infty, \infty)$ are not homeomorphic, that's a bit trickier. Once you know about compactness it's easy. The first other approach I can think of is to identify some property that the endpoints have which no interior points can have. For example, any connected open set containing 1 has the property that when you remove 1 its still connected.