From: Anders Sandberg (asa@nada.kth.se)
Date: Sat Nov 01 1997 - 13:41:11 MST
EvMick <EvMick@aol.com> writes:
> In a message dated 97-11-01 03:40:49 EST, you write:
>
> << Iron is generally an easily
> alloyed metal, probably due to the fact that it switches crystal structures
> (between BCC, FCC, and HCP) easily under fairly mild conditions. As for
> amorphous crystals, I don't think metal crystals can be amorphous. If I am
> not mistaken, amorphous crystals can only occur when there is l >>
>
> Ok...that sounds good....except I don't understand it...
>
> What does BCC, FCD and HCP mean? And what does Amorphous mean in this
> context...
BCC = Body Centered Cubic
FCC = Face Centered Cubic
HCP = Hexagonal Close Packing
These are three ways of placing atoms in a lattice. See
http://abe.msstate.edu/classes/abe3813/prop3.htm for some (bad)
pictures, and http://matse1.mse.uiuc.edu/~tw/metals/prin.html for some
slightly better pictures.
Amorphous materials do not have a regular lattice structure; the atoms
are arranged more or less randomly.
> Addittionally...how would this idea of a crystalline core tie in with the
> concept of the polarity of earths magnetic..."flipping' or reversing every so
> often...how would (could) this happen...and what (if any) visible effect would
> there be.?
It is likely not the solid inner core that creates the magnetic field,
rather the liquid outer core. There are dynamo processes where the
flow of conducting core material, the earth's rotation and the
magnetic process interact which could be chaotic, creating flips from
time to time. I guess a crystaline core might interact with this
process, likely as a damping term in the equation. The visible effects
do not appear to be very large, although the cosmic radiation level
would likely rise during the reversal.
Just to get this into a more transhumanistic vein: any ideas for how
to influence these processes to avoid/cause a pole reversal?
> And just to throw a nother bean into the stew...how does Gold's Primeval Oil
> thesis tie into this?
As far as I know, not at all. It is all about what happens up at the
crust, not down in the core.
-- ----------------------------------------------------------------------- Anders Sandberg Towards Ascension! asa@nada.kth.se http://www.nada.kth.se/~asa/ GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y
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