bio  website  math.temple.edu/~rivin 

location  USA  
age  
visits  member for  4 years, 7 months 
seen  6 hours ago  
stats  profile views  14,720 
Professor of Mathematics at Temple University. Regius Professor of Mathematics at St Andrews starting Fall 2015.
20h

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Stability of the Solar System
First, they came for Mars... 
20h

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Stability of the Solar System
@GerhardPaseman Planets leaving, other planets crashing into the Sun. O, the humanity! 
21h

answered  Probability a random matrix contains a short integer vector in its kernel 
21h

answered  Stability of the Solar System 
23h

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How to prove the existence of the polytope in $\mathbb{R}^d$ with a given number of faces, minimizing the isoperimetric ratio?
@student The volume is the same as when you would count the face one, but the area is bigger. 
23h

answered  How to prove the existence of the polytope in $\mathbb{R}^d$ with a given number of faces, minimizing the isoperimetric ratio? 
1d

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Algebraic independence in normed spaces
By the way, I had trouble backing out the statement from the lemma you mention (I did not try very hard to unravel all the jargon, it's true...) 
1d

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Identities involving sums of Catalan numbers
Your RHS equals the expression in the answer... 
2d

answered  Identities involving sums of Catalan numbers 
2d

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Algebraic independence in normed spaces
I don't see how you would be able to say anything in general (since the algebricity of the $l^2$ norm is obviously essential); the $l^p$ case is obviously quite special. 
2d

answered  Is the boundary of an open, regular, bounded, pathconnected, and simply connected set a Jordan curve 
2d

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Determining if a matrix is orthogonal
added more info. 
2d

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Determining if a matrix is orthogonal
@YCor Yes, correct. That's what happens when you do this too late at night :) 
2d

answered  Determining if a matrix is orthogonal 
2d

revised 
Determining if a matrix is orthogonal
fixed TeX 
Jul 1 
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How to determine an unitary operator involved in an unitary transformation?
Why? What's wrong with the 1962 method? 
Jul 1 
answered  How to determine an unitary operator involved in an unitary transformation? 
Jul 1 
answered  Given $x$ in a pathconnected open set $S$ on the plane, are there noncrossing paths from $x$ to every point in $\partial S$? 
Jul 1 
answered  $P_3$factors for 3regular, 3connected cubic graphs 
Jul 1 
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$P_3$factors for 3regular, 3connected cubic graphs
Sleuthing shows that $P_k$ is a path on $k$ vertices, so the OP's question is whether the vertices of $G$ can be decomposed into triples, where each triples forms the vertex set of a path on three vertices, and these paths are disjoint. 