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Re: [Phys-l] expand your mind



"homogeneous == same everywhere
isotropic == same in all directions"

antonyms: inhomogeneous and anisotropic. Why not anhomogeneous and inisotropic, inter alia?

bc


p.s. If the strands are braided it's a Challah bagel!
_____



John Denker wrote:

I wrote:


constrained by friction against whatever it's sitting on while it rises.


Here's a simpler way to minimize friction during rising: Build a
"bagel boat" by cutting a piece of buoyant wood (e.g. balsa wood)
into N pieces:
http://www.av8n.com/physics/img48/bagel-boat.png

It's like an ordinary raft, except that it has _expansion joints_
between the pieces.

Put the not-yet-risen bagel on the bagel boat, and then float it
in a shallow dish of water.

This should allow it to expand more-or-less isotropically ... so
that the hole in the middle expands as everything else does.

==============

Also, to minimize memory effects due to internal stress, two
possible lines of attack:

1) Make a big flat sheet of dough and cut out an annulus using a
donut cutter (or knife or scissors); or

2) If you like to build your bagels by creating a cylinder and then
joining the ends to make a torus, proceed as usual but make the
cylinder N times thinner (and therefore N^2 times longer), where
N is at least 2 and preferably greater. This may well require
making several separate strands, rather than one reeeally long
one. Then build the bagel by wrapping the strands around and
around and around. (Optionally you can get artistic with this
if different strands have different properties: whole wheat
versus not, cinnamon in the dough versus not, et cetera.)


*) Keep in mind that the goal is to minimize internal stresses,
or at least to make the stresses homogeneous and isotropic.
homogeneous == same everywhere
isotropic == same in all directions
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