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Math Professor

Oct
18
comment Inequality for an integral involving $ \exp $, $ \sin $ and $ \cos $
@Christian Rempling: integral of $x\sin(2\pi x)$ over this range will depend on $k$. And the desired estimate does not depend on $k$.
Oct
18
revised Inequality for an integral involving $ \exp $, $ \sin $ and $ \cos $
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Oct
18
comment Inequality for an integral involving $ \exp $, $ \sin $ and $ \cos $
What range of $t$ are you interested in?
Oct
18
answered Inequality for an integral involving $ \exp $, $ \sin $ and $ \cos $
Oct
17
comment Hill's discriminant and spectral properties of Schrödinger operator
They do not claim that they arguments constitute a proof of theorem 1: instead they refer to [6,16].
Oct
16
comment Analytic extension of the exterior Newtonian potential into the domain
The boundary of these domains is analytic. Look in the literature I recommended.
Oct
16
comment Analytic extension of the exterior Newtonian potential into the domain
Can someone explain her reasons for closing this question??
Oct
16
revised Analytic extension of the exterior Newtonian potential into the domain
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Oct
16
answered Analytic extension of the exterior Newtonian potential into the domain
Oct
13
comment Is this series well known?
@Dirk: Why almost? Is $(n^2)!$ "almost" $n^2$?
Oct
13
comment Is this series well known?
@Brendan McKey: $n$-th term becomes the biggest when $t\sim n^2$.
Oct
13
comment Is this series well known?
@Dirk: How it is related to the integral of theta-function? Where will $(n^2)!$ in the denominator will come from?
Oct
12
comment Non-smooth function with all differences of translates smooth?
@Bob Yuncken: right. Everything is fine for periodic functions. But it is probably true without any growth restriction (with a different proof not using any Fourier transform).
Oct
12
revised Non-smooth function with all differences of translates smooth?
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Oct
11
revised Non-smooth function with all differences of translates smooth?
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Oct
10
comment Non-smooth function with all differences of translates smooth?
@Bob Yuncken: Bob, there is a lot of possibilities for generalization. For example, $f$ can be periodic and locally $L^1$, or in Schwartz temperate distribution space. Some growth conditions are however necessary for Fourier analysis to work. It is actually strange that the answer to such question may depend on the growth of $f$ rather than just local properties. But I do not see how to get rid of the growth conditions completely.
Oct
10
revised Non-smooth function with all differences of translates smooth?
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Oct
10
comment Non-smooth function with all differences of translates smooth?
@Jochen Wengenroth: you are right. We need derivatives in $L^1$. I made a correction.
Oct
10
revised Non-smooth function with all differences of translates smooth?
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Oct
10
revised Non-smooth function with all differences of translates smooth?
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