Lee Mosher

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Name	Lee Mosher
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8h	comment	embeddings of graphs into surfaces Regarding question 1, your two assumptions together imply that $rank(\Gamma)=2genus(S)$, because the first says $1−r \ge 1−2g$ and surjectivity of $i_∗$ implies $r \ge 2g$. Is that the intent?
2d	comment	Why is the length R cosine theta? Your question, while interesting, is off topic at this site, which is for questions of mathematical research. Try another site like math.stackexchange.com
Jun 15	accepted	What are the best settings for the large scale geometry of locally compact groups?
Jun 15	answered	Why are negative sets multisets? (Reference request)
Jun 14	comment	What is the moduli space of germs of one-sided complex structures near the circle? My answer is written with sufficient generality to cover that assumption: the cusp is ruled out, and only the other case remains.
Jun 14	answered	What is the moduli space of germs of one-sided complex structures near the circle?
Jun 13	comment	Proper Group action on a metric space Being a length metric is irrelevant. On the other hand, you ought to assume the metric space is proper (closed balls are compact), particularly since you are assuming that the action is proper (the induced map $G \times X \to X \times X$ is a proper function). In that case what you ask for is true, and is a trivial consequence of the definitions.
Jun 13	comment	What are the best settings for the large scale geometry of locally compact groups? And I see that my answer has crossed with David's pointer to Yves Cornulier's paper.
Jun 13	answered	What are the best settings for the large scale geometry of locally compact groups?
Jun 12	answered	Random metrics on compact orientable surfaces
Jun 12	comment	Distortion of tree embedding in Alexandrov spaces Oops, sorry, my eyes saw "non-negative" and my brain saw "non-positive".
Jun 12	comment	Distortion of tree embedding in Alexandrov spaces You might want a narrower focus which rules out negatively curved spaces in which the infinite binary tree embeds with uniform value of $D$.
Jun 3	comment	Where to look for corrections of papers? If the paper is published in a journal and has a published correction, sometimes MathSciNet will bundle the review of the original paper and its correction into a single entry; the extreme rarity of this practice is a clue to the extreme rarity of published corrections. Also, if you have downloaded the paper from the arXiv, keep a lookout for later versions on the arXiv or in a journal, either of which is quite likely to contain corrections/revisions/updates of earlier versions.
May 31	comment	Geometry defined by foliation. Do you mean "lines PARALLEL to each axis"?
May 29	comment	Is there any finitely-long sequence of digits which is not found in the digits of pi? Voting to close meta.mathoverflow.net/discussion/1601/…
May 28	comment	complete metric space What is left unsaid in the answer and the wikipedia link is that the original metric and the "intrinsic metric" can be pathologically different. For example, if $X$ is the Cantor set or any other totally disconnected metric space then dist completely degenerates to the unique $0,\infty$ extended metric.
May 26	comment	Universal covering of compact surfaces Daniele's construction is not so much an application of the classification of surfaces, and more an application of the Poincare polygon theorem, in order to obtain the universal covering map with domain $\mathbb{H}^2$ using the gluing pattern for the specific surface asked for by the OP.
May 25	revised	Classification of geometric outer automorphisms of free groups added 529 characters in body
May 25	answered	Universal covering of compact surfaces
May 23	comment	$P^1$ minus k points The derivation of the matrices should be covered in any textbook on hyperbolic geometry. In outline, if you fix the polygon $P$ in the upper half plane model, each side pairing $a_i \mapsto \bar a_i$ takes the endpoints of $a_i$ to the endpoints of $\bar a_i$. Once the image of a third point at infinity is determined, the matrix is determined. There is also a completeness condition for each cusp: the monodromy around that cusp must be parabolic. With that, you get a very explicit set of formulas parameterizing the matrices.
May 23	revised	Hyperbolic pair of pants. added 74 characters in body
May 23	revised	Hyperbolic pair of pants. deleted 102 characters in body; edited body
May 23	revised	Hyperbolic pair of pants. deleted 14 characters in body
May 23	answered	Hyperbolic pair of pants.
May 22	answered	$P^1$ minus k points
May 22	comment	Does this qualify as “self plagiarism” or something? Here is a general rule which I tell my students when they need to write background material which they learned from another source, and which perhaps applies to material from ones own earlier writings. Don't be lazy: learn the old references in your heart of hearts, and then rewrite it anew the way you need it for your current paper.
May 21	comment	What does a singular simplex with real coefficient mean Perhaps you meant "references on singular homology". I would recommend Hatcher's book, which explains the distinctions between simplicial homology and singular homology. It is available at math.cornell.edu/~hatcher/AT/ATpage.html
May 20	comment	What does “Vertex Solution” mean? A citation of the paper or book in which you found this phrase, for example.
May 18	comment	What is an interpretation of the relation in the cohomology of the pure braid groups? At least you will have a lot of time to draw pictures of braids in the sand.
May 16	revised	Computation of Ext(Z^N,Z) edited body
May 16	comment	What are these compact sets called? How about just a "piecewise smooth set"?
May 13	comment	Mapping class group of once-punctured torus I guess what I mean is that what I would write in this situation is: "The proof for $T$ is given in [FLP], and the proof for $S$ follows immediately from the definitions."
May 13	answered	The role of the Automatic Groups in the history of Geometric Group Theory
May 13	answered	Mapping class group of once-punctured torus
May 9	comment	Jordan curve theorem: Can every point on the curve be reached from each region? Actually, what you state is not the full "Jordan Schonflies theorem". The full statement of the Schonflies theorem is that there is a homeomorphism of the plane taking $C$ to $S^1$, from which your property follows easily.
May 9	revised	Trees in groups of exponential growth edited tags
May 9	accepted	Converse to Milnor’s theorem on manifolds with nonnegative Ricci curvature.
May 9	revised	Converse to Milnor’s theorem on manifolds with nonnegative Ricci curvature. added tag geometric-group-theory
May 8	revised	Converse to Milnor’s theorem on manifolds with nonnegative Ricci curvature. added 81 characters in body
May 8	revised	Converse to Milnor’s theorem on manifolds with nonnegative Ricci curvature. added 89 characters in body
May 8	answered	Converse to Milnor’s theorem on manifolds with nonnegative Ricci curvature.
May 8	comment	Discrete disjoint covering of integer lattices @Some guy: This change, from "basis-and-origin simplex" to "minimal integer simplex", changes the mathematical content of your question and confuses the issue. For example, {(0,0),(34,21),(21,13)} is a "minimal integer" simplex, but it is not a translate of the basis-and-origin simplex. Was that your intent?
May 7	revised	Dehn presentation of a knot group edited tags
May 7	revised	Why isn’t $\langle x,y,z\|xyzx^{-1}y^{-1}z^{-1}\rangle$ a hyperbolic surface group? edited tags; edited tags
May 7	revised	Polynomial growth of the Betti number of balls of the Cayley graphs edited tags
May 7	comment	Periodic automorphisms of free groups and surface homeomorphisms You're welcome, Sebastian.
May 7	accepted	Periodic automorphisms of free groups and surface homeomorphisms
May 6	answered	Classification of geometric outer automorphisms of free groups
May 6	answered	Periodic automorphisms of free groups and surface homeomorphisms
May 6	comment	Periodic automorphisms of free groups and surface homeomorphisms When you speak about automorphisms of free groups, do you really mean outer automorphisms? I ask because $h : M \to M$ does not induce a well-defined automorphism of $\pi_1 M$, at best it induces an outer automorphism.

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