bio  website  math.ubc.ca/~israel 

location  Vancouver BC  
age  63  
visits  member for  3 years, 8 months 
seen  4 hours ago  
stats  profile views  5,139 
Associate Professor Emeritus, University of British Columbia, and Optimization Algorithms Researcher, DWave Systems, Burnaby BC
1d

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Estimating the moments of a random variable
Upper and lower bounds for $k$ might be helpful. 
Nov 23 
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Probability of close approach for multivariate normal variables
Are $x$ and $y$ independent? 
Nov 21 
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Norm of swapped power series in the unit disk
Almost any polynomial, suitably scaled, is either $f$ or $g$ for a counterexample. 
Nov 21 
answered  Continuity in Banach space for nonlinear maps 
Nov 20 
answered  Efficient computation of null space of large symbolic matrices? 
Nov 17 
answered  Does this equation has a closedform solution for $t$? ($(1p)\sum_{i=0}^{n}t^i = p\sum_{i=0}^{n}(1t)^i)$) 
Nov 17 
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Does this equation has a closedform solution for $t$? ($(1p)\sum_{i=0}^{n}t^i = p\sum_{i=0}^{n}(1t)^i)$)
Yes, the point is that it factors, and the cubic factor is the one that contains $p$, so that's what you're actually solving. 
Nov 17 
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Does this equation has a closedform solution for $t$? ($(1p)\sum_{i=0}^{n}t^i = p\sum_{i=0}^{n}(1t)^i)$)
For $n=5$ you're solving the cubic $${t}^{3}7\,p{t}^{2}+2\,{t}^{2}+7\,pt+2\,t7\,p+1$$ 
Nov 13 
answered  How to find equilibrium of the following game? 
Nov 13 
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How to find equilibrium of the following game?
I don't understand what you say about $p = 1/2$. It seems to me that $(1/2, 1/2)$ is never an equilibrium: it's better for either player to choose either $0$ or $1$ (to get payoff $1/2$) instead of payoff $1/4$ at $(1/2, 1/2)$. 
Nov 12 
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A nilpotency question on $C^{*}$ algebras
I suppose you aren't interested in commutative $A$'s? 
Nov 11 
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Existence of arithmetic function satisfying a certain property
I don't think you mean $n_1 + n_2 + \ldots n_k = 0$ if $n_1, \ldots, n_k \in \mathbb N$. What do you really mean? 
Nov 11 
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Are there infinitely many primes p such that both p1 and p+1 have at most 3 prime factors, counted with multiplicity?
Dickson's conjecture would imply that there are infinitely many members of the subsequence where, e.g., $(p1)/6$ and $(p+1)/4$ are prime. 
Nov 10 
revised 
Random walks with exponential decreasing steps
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Nov 10 
revised 
Random walks with exponential decreasing steps
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Nov 10 
revised 
Random walks with exponential decreasing steps
added 398 characters in body 
Nov 10 
answered  Another type of derivative, and the associated primitive 
Nov 10 
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Counterexample for closed graph theorem in unmetrizable case
The Closed Graph Theorem requires some conditions on $X$ as well, e.g. that it is a barrelled space. Otherwise, for a counterexample take any closed unbounded (partially defined) operator $A$ in a Banach space $Y$, and let $X = {\mathscr D}(A)$ with the topology of $Y$. 
Nov 10 
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Random walks with exponential decreasing steps
No, you won't. $1 + g  g^2  g^3  g^4  g^5 = 3  \sqrt{5} > 0$. 
Nov 9 
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Random walks with exponential decreasing steps
If the walk ever fails to return when $n$ is a multiple of $3$, then it will never return. 