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Old 12-24-2009, 11:47 AM   #4
Erick Mead
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Dojo: Big Green Drum (W. Florida Aikikai)
Location: West Florida
Join Date: Jun 2005
Posts: 2,616
Re: Gravity and the body

Oisin Bourke wrote: View Post
Or, to really push the conceit: in aikido terminology one might express it as from:
comes and

That's a stretch, but it's food for thought.

I wonder, then, how gravity might be differentiated in the body. Does it act on either side of the body? or on the front and back side of the body. Or as one part lowers/sinks, the other rises.

Thanks for your thoughts. I'm going to mull over this for a while.
Read Kisshomaru again. "Spherical" action. Then go look up spheroidal waves and their normal modes. Radial and tangential oscillations = "S-mode" radial (breathing); and "T-mode" tangential oscillations -- (torquing/untorquing -- also rolling toroidal waves) deformations of the sphere. These can act together.

A sphere under gravity squashes (oblate), if that occurs dynamically, its reaction is to unsquash (prolate) - this and uniform radial ballooning oscillation are S-mode spheroidal waves.

If you take a nerfball on a rug and press without squashing it, and then torque it, it reduces in radius creating a direct conversion between S-mode and T-mode action. This is called asagao in traditional terms. Toroidal waves along the surface of the sphere dissipate in energy as they diverge in approaching the equator and concentrate as they converge in approaching the polar extremities es, and then bounce back again. (Fajin, for those who care). These toridal waves also create cross-coordinated gross radial deformation effects -- prolating in approaching the extremities and oblating it as they approach the equator.

-- But the torsional shear stress line diagonals in the body (L hand to R foot and R hand to L foot) themselves torque/untorque and squash/unsquash inversely to one another, thus allowing an applied torque or squash to be accepted by the inverse action on the unloaded diagonal -- shearing the applied load perpendicularly without opposing it -- essentially a field effect of keeping the stress paths in the body coherent and continuous, and not countering.


Erick Mead
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