bio | website | shef.ac.uk/nps |
---|---|---|
location | Sheffield | |
age | 48 | |
visits | member for | 4 years, 9 months |
seen | Jul 18 at 12:51 | |
stats | profile views | 8,077 |
I am an algebraic topologist, based at the University of Sheffield.
Jul 17 |
comment |
Intuition behind Kronecker's congruence?
What is $j$? If $Y$ is an indeterminate, how is $\alpha(Y)$ meaningful? |
Jun 24 |
comment |
A question about the Leray-Serre spectral sequence
The Milnor hypersurfaces give a nice example of the phenomenon that @CraigWesterland mentioned. This is Example 3.3 in my notes at shef.ac.uk/nps/courses/bestiary/ss.pdf |
Jun 4 |
comment |
Can we construct a Baas-Sullivan presentation of TMF?
As Tyler explains, you cannot get $tmf$ as a Baas-Sullivan quotient of $MU$. I do not know whether you could get it as a Baas-Sullivan quotient of $MO\langle 8\rangle$. That is an interesting question, but much harder to address because of the complicated structure of $\pi_*(MO\langle 8\rangle)$ and $\pi_*(tmf)$. My guess is that the answer is negative, but it would be nice to be proven wrong. |
May 31 |
comment |
Nilpotency of BG^+
You should bear in mind the Kan-Thurston theorem: for any connected space $X$ there exists a group $G$ and a perfect subgroup $P$ such that $BG^+_P=X$. |
May 27 |
answered | classification of $p$-groups |
May 22 |
answered | K-groups of a permutative category - are they finite? |
May 17 |
reviewed | Leave Open Category = Groupoid x Poset? |
May 17 |
reviewed | Leave Open The classifying space of an infinite totally ordered set is contractible |
May 17 |
comment |
The classifying space of an infinite totally ordered set is contractible
The two maps combine to give a poset map $\{0,1\}\times P\to Q$, and $B(\{0,1\}\times P)=[0,1]\times BP$. |
May 17 |
comment |
The classifying space of an infinite totally ordered set is contractible
The space $BP$ is topologised as the colimit of the spaces $BQ$, as $Q$ runs over finite subsets of $P$. So a subset $F\subset BP$ is closed iff $F\cap BQ$ is closed with respect to the obvious topology on $BQ$, for all $Q$. |
May 17 |
answered | The classifying space of an infinite totally ordered set is contractible |
May 14 |
comment |
What questions should -ologists of mathematics ask, in order to improve maths researcher training?
The link that you gave suggests that the project is focused on developing countries that do not already have a strong research culture. Answers in that context will be very different from answers in the more obvious context of US and European research universities. You should clarify which context you are interested in. |
May 14 |
revised |
What questions should -ologists of mathematics ask, in order to improve maths researcher training?
Added text from the first link |
May 12 |
reviewed | Close Integral kernels of self-adjoint operators |
May 12 |
reviewed | Leave Open Can the image of a disk have nontrivial Hausdorff measure for $1 < d < 2$? |
May 12 |
reviewed | Leave Open Finite groups normalizing a torus |
May 5 |
reviewed | Leave Open Continuity of function mapping $\mathcal{P}(\mathcal{P}(X))$ to $\mathcal{P}(X)$ |
May 5 |
reviewed | Leave Open If the quotient of an algebraic space $X$ by a finite group is a scheme, is $X$ a scheme? |
May 5 |
reviewed | Leave Open Reference request: Flipping the factors in the Künneth formula |
May 2 |
awarded | Nice Answer |