On Dec 22, 10:52*am, Darryl Ramm wrote:
On Dec 22, 7:50*am, Grider Pirate wrote:

No, actually, it happens as I approach the speed of light.

While looking aft.

Matt may be confused or just maybe he is showing off. A relativistic
glider pilot facing forward (and looking around a bit)will observe a
combination of red and blue shift.

Classical Doppler effect is of course inline to the direction of
relative motion. So blue shift going towards and redshift going away.
But relativistic Doppler will redshift objects even those with no line
of motion towards/away form you. The overall red shift/blue shift
shapes into a cone with things to the side of you red shifted as well.
There is a nice 2D animation of the relativistic Doppler cone athttp://en..wikipedia.org/wiki/Relativistic_Doppler_effect.

BTW I hear the new ClearNav vario includes corrections for
relativistic Doppler effects (but no word yet if it will actually talk
to any PDA based soaring software).

Darryl


A couple of things come to mind.

Euler's equations

Our world has three spatial dimensions (up-down, left-right, fore-aft)
and one time dimension. In general, the Euler equations have a time-
dependent continuity equation for conservation of mass and three time-
dependent conservation of momentum equations. At the top of the
figure, we show a simplified, two-dimensional, steady form of the
Euler equations. There are two independent variables in the problem,
the x and y coordinates of some domain. There are four dependent
variables, the pressure p, density r, and two components of the
velocity vector; the u component is in the x direction, and the v
component is in the y direction. All of the dependent variables are
functions of both x and y. The differential equations are therefore
partial differential equations and not ordinary differential equations
that you study in a beginning calculus class.


The second more apt sailboat racing term

LTO (lightning tack to oblivion)

Richard
www.craggyaero.com