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bio website scholarpedia.org/article/…
location Arizona
age 47
visits member for 2 years, 3 months
seen Dec 15 at 20:27

Author of the Wikipedia pages Kepler's Equation, and Radial Trajectory. Assistant editor at Scholarpedia. Google+ profile.


Sep
22
comment How to write $a^{ix}$ in terms of $\sin(x)$ and $\cos(x)$?
$e^{\ln(a)}$ is single valued for $a \ne 0$.
Sep
20
comment How to write $a^{ix}$ in terms of $\sin(x)$ and $\cos(x)$?
$a=e^{\ln a}$ is true for negative values of a: $(a=e^{\ln a}, a\neq 0)$.
May
6
comment Can this gravitational field differential equation be solved, or does it not show what I intended?
The correct differential equation is: $ - \frac{G M m}{r^2} = \mu \ddot r $ where $ \mu = \frac{M m}{M+m} $ is the reduced mass.
May
1
comment Can this gravitational field differential equation be solved, or does it not show what I intended?
The correct equation is: $$ - \frac{G M m}{r^2} = \frac{M}{M+m} m \ddot r $$
Mar
30
comment Are constant numbers (rank-0 tensors that are fixed) considered as symmetric tensors?
The Kronecker delta is a rank 2 tensor.