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Theoretical physicist by training, PhD in spin-polarized quantum systems. Inventor of the DPD micro-hydrodynamics simulation methodology, and specialized in computational physics. Currently chief scientist for a major corporation. Blogger at Science2.0.


Apr
7
awarded  Great Answer
Apr
3
awarded  Good Answer
Apr
2
awarded  Nice Answer
Apr
1
comment Visually stunning math concepts which are easy to explain
The visual is not explaining why (given the three specific squares) the red triangle is a right triangle.
Apr
1
answered Visually stunning math concepts which are easy to explain
Mar
30
comment Gaussian Quadrature Confusion
It boils down to $\int_{-a}^{+a} x^m dx = 0$ for odd $m$.
Mar
30
comment Gaussian Quadrature Confusion
the terms corresponding to the even coefficients $c_n$ do not contribute to the integrals of $x^k q(x)$ with odd $k$ over an interval symmetric around $x=0$. Similarly, the terms corresponding to the odd coefficients $c_n$ do not contribute to the integrals of $x^k q(x)$ with even $k$ over an interval symmetric around $x=0$.
Mar
30
comment Gaussian Quadrature Confusion
When the even coefficients ($c_0$ and $c_2$) are set to zero, the integral condition is satisfied for all even powers of $x$.
Mar
29
revised weighted average with exponential weighting
Reaction to edits in question
Mar
29
revised weighted average with exponential weighting
Reaction to edits in question
Mar
29
revised weighted average with exponential weighting
Subscript corrected
Mar
29
comment weighted average with exponential weighting
Following your edits, it seems your question is different. Do I understand correctly that you propose a generalized mean of the form: $(w(x_1) + w(x_2) + ..) <x> = w(x_1)x_1 + w(x_2)x_2 + ..$ ?
Mar
29
revised How to win this game?
Title, wording
Mar
29
suggested suggested edit on How to win this game?
Mar
29
answered weighted average with exponential weighting
Mar
29
revised Find the width of the river.
Removed irrelevant units
Mar
29
answered Find the width of the river.
Dec
9
awarded  Yearling
Aug
16
answered How many balls were drawn? (a combinatorial problem)
Aug
12
comment The puzzle of billiard geometry
It is essential that the mirror is placed inside the billiard, about a ball radius away from the edge.