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Jun
25
comment Fourier transform of a signal sequence?
I would be sort of surprised if there is an analytic formula for the Fourier transform of this contrived function.
Jun
18
awarded  Good Answer
May
29
revised How find the number of $z$,such that$ |a^2-b^2-b+1|\le 10$
added 365 characters in body
May
29
answered How find the number of $z$,such that$ |a^2-b^2-b+1|\le 10$
May
28
answered Evaluate integral in terms of Gamma function
May
24
revised Grover Algorithm Orthogonal vectors
added 15 characters in body
May
24
comment Grover Algorithm Orthogonal vectors
Sorry, I made a mistake. I meant that $\omega$ and $s'$ are orthogonal. My answer is hopefully fixed. I don't understand the question "how I will be able to define $\sqrt{N}|\omega\rangle$". It's just multiplication, right? One should know how to multiply vectors by numbers.
May
24
answered Grover Algorithm Orthogonal vectors
May
7
awarded  Yearling
Feb
3
awarded  Enlightened
Feb
3
awarded  Nice Answer
Dec
15
answered Fourier transform vs Fourier series
Dec
9
comment Rotation matrix in terms of axis of rotation
It's just a conjugation of the simple matrix for a rotation around the $z$-axis, which is effectively just 2 x 2 matrix, by another rotational matrix that rotates the North pole to the point $V$, which is a product of rotation in the theta-direction and the phi-direction to get where you need to get. Conjugation by $U$ is $URU^{-1}$ where the product is matrix product. It's possible ineffective to write these things without matrices so if you don't know matrices, this is a reason to learn them. At any rate, it's not really physics, it's linear algebra and geometry and a basic one.
Dec
2
comment Kummer's Equation
Dear Alex, the equation for $L_n$ is nothing else than a coefficient in front of $t^n$ in the Taylor expansion of the equation for $g$ with respect to $t$. You just compare the terms term-by-term. Please just expand my equation for $g$ as a Taylor expansion in $t$ and don't ask any more questions.
Dec
2
answered Kummer's Equation
Sep
21
awarded  Custodian
Jul
18
awarded  Good Answer
Jun
22
awarded  Enlightened
Jun
22
awarded  Nice Answer
May
23
comment A general pattern to find the roots of the classical lie algebras
Sorry, your updated question got very confusing. I was answering your original question. The new question talks about "levels" etc. There aren't levels in ordinary Lie algebras. The roots are very simple objects and be sure I could easily enumerate all of them for all 7 classes of the Lie algebras, A,B,C,D,E,F,G. They're just the non-negative integral combinations of the simple roots that have the right length (either the same as simple roots or, in non-simply-laced groups, sqrt2 or sqrt3 times longer). ... If you have an algebra, the roots are just defined as the eigenvalues under the Cartan.