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bio website math.ubc.ca/~israel
location Vancouver BC
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Associate Professor Emeritus, University of British Columbia, and Optimization Algorithms Researcher, D-Wave Systems, Burnaby BC

42m
comment 0-1 Integer Problem, On Constructing A General Case Algorithm
Look up "knapsack problem".
3h
answered For what real $t$ is $\{n^t : n \geq 1\}$ linearly independent over $\mathbb{Q}$?
5h
comment For what real $t$ is $\{n^t : n \geq 1\}$ linearly independent over $\mathbb{Q}$?
Has to be linearly. $4^t = (2^t)^2$.
2d
revised Multivariable function analysis
added 665 characters in body
2d
answered Multivariable function analysis
Apr
24
comment Multivariable function analysis
Since you say "polynomial", is $k$ to be an integer $\le n$? By "largest" do you mean largest in absolute value, or greatest real root, or what?
Apr
24
comment Solving complicated equation involving integral of error functions
It seems extremely implausible that in general there would be a closed form for the integral, much less a closed-form solution to the equation, if that's what you're asking.
Apr
23
comment Extension of conformal map and annulus
Yes, I took "circle" in the geometric sense.
Apr
23
answered Extension of conformal map and annulus
Apr
21
answered First collision time of $n$ random walkers on a cycle
Apr
18
awarded  Nice Answer
Apr
16
comment Densely-defined operator with closed range: conditions for operator closed
In particular, the closedness of the range doesn't really help much. For example, suppose $X = U \oplus V$ with $\text{dom}(A) = (\text{dom}(A) \cap U) + (\text{dom}(A) \cap V)$. The image of $U \cap \text{dom}(A)$ might be all of $Y$, in which case $\text{rng}(A)$ is certainly closed, but that says nothing about what happens on $V$.
Apr
16
comment Densely-defined operator with closed range: conditions for operator closed
What sort of conditions are you looking for? You're not likely to get much other than restatements of the definition of closed operator.
Apr
16
comment Sum of two unbounded self-adjoint operators
Well, then you could take $B = -A$, and $A + B = 0$ is certainly not self-adjoint on $D(A)$.
Apr
15
comment Motivation for the existence of periodic solutions
I would suggest not closing, as there might be good answers from the mathematical dynamical-systems point of view.
Apr
15
comment Uniquely ergodicity and polynomial ergodic average
Since you say "average", I presume you're dividing these sums by $n$.
Apr
15
revised Proof that image of a polynomial map is a cone
edited body
Apr
14
comment Is there a closed form for tan(q*pi) with q rational?
You left out a factor $-i$.
Apr
14
answered Holomorphic functional calculus and idempotents
Apr
13
answered Proof that image of a polynomial map is a cone