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Old February 2nd 08, 12:58 PM posted to sci.physics, sci.astro
sean
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Posts: 173
Default Earths Magnetic Field

On Jan 23, 2:54*pm, "Androcles" wrote:
"sean" wrote in message

...
|I have also supplied a graphic explanation of the `Variable speed Core
| ` model at the following url
|
|http://www.youtube.com/watch?v=CiCBrXKIH_0
|
| ...to accompany the model outlined below...
|
|
|
| Studies of the seismic record indicate that seismic waves travel
| fastest along a north-south axis from the southern hemisphere to
| Siberia (and more recently suggesting an easterly shift to over
| Alaska) implying that over the the last century it appears that the
| earths solid core is rotating in an easterly direction. The conclusion
| made from this data is that the earths solid inner core can be said to
| be rotating west to east at approximately 1 degree longtitude a year
| faster than the mantle.(Song, Richards 2005) *This implies then, that
| relative to Earths solid inner core, the mantle and the outer part of
| the liquid core can be said to be moving in a westerly direction. This
| also implies that there must be *speed gradient in the liquid core
| across its radius (relative to the mantle), of approximately 0 degrees/
| year near the mantle to 0.1 degreeslongtitude/year near the solid
| core. Thus using Lenzs` law, one can predict that the larger volume of
| the outer part of the liquid core will induce a residual westerly
| electrical current in the inner part of the liquid core (ie the outer
| liquid core moves in a westerly direction relative to the inner part
| of the liquid core). Flemings Right Hand rule predicts this westerly
| direction of the electrical current will in turn induce a magnetic
| south pole near Earths geographic North Pole. Recent experiments
| confirm this, in that a freely rotating liquid metal will generate a
| self sustaining magnetic field without a neccesary seed magnetic field
| to kickstart the dynamo effect as previously thought.(Generation of a
| Magnetic Field by Dynamo Action in a Turbulent Flow of Liquid Sodium.
| R. Monchaux et al 2007).
| As the seismic record shows that sound waves travel fastest across
| earths N-S axis, this could also be consistent with the solid inner
| core being slightly elongated in the earths N-S axis. (sound waves
| travel fastest in a denser medium) Following from this, it can be
| hypothesised that contrary to the speculation that the earths core is
| a rigid crystal, one could alternatively give the `solid` inner core
| non rigid, or elastic properties. Observations support this
| possibility (Andrew Jephcoat and Keith Refson (2001-09-06). "Earth
| science: Core beliefs". Nature 413: 27-30. doi:10.1038/35092650.) If
| so its shape could then be said to oscillate over large timescales
| between that of elongated in the N-S axis to stretched along the
| equatorial plane. Obviously this implies that the inner cores`
| rotational speeds would vary between slower and faster than the
| mantle, when the solid core goes from wider at the equator to
| stretched at the poles respectively. The historical record of Earths
| pole reversals and changing field strength can thus be well modeled by
| this variable core speed model. In that if currently it is accepted
| that the `solid core` is stretched is the north south axis and rotates
| faster than the mantle then it follows that when the cores volume
| changes shape to that of more stretched in the equatorial axis, It
| must then be forced to slow its rotational speed and therefore rotate
| slower than the mantle . Not faster as currently observed. (ie the
| core then will rotate in a westerly direction relative to the mantle)
| In turn this would reverse the relative motion between the inner and
| outer parts of the liquid core (as described above)
| and in turn reverse the induced equatorial direction of the induced
| electrical current which would then reverse the direction of earths
| induced magnetic field from N-S to S-N. THis is observed in the
| historical seismic record.
| The current weakening of Earths magnetic field must then be due to the
| solid cores` rotational speed slowing relative to the mantle. In other
| words if it is assumed that currently the core is observed to be
| travelling faster than the mantle in an easterly direction at 0.1
| longitude per year than that rate must have been faster in the past
| and will be slower in the future. This can only be explained if it is
| assumed that the `solid` core itself is becoming less stretched in the
| N-S axis and tending towards becoming stretched in the equatorial
| axis.
| To explain the observed off axis magnetic North pole using this
| `variable core speed model` one can again refer to the seismic record
| which shows that the *axis of anisotropy, corresponding to the fastest
| direction for seismic waves, tilts about 10 degrees from the Earth's N-
| S axis of rotation, towards Siberia. From this data *one can interpret
| that the inner core not only could be `stretched` in the N-S axis but
| also be physically tilted *10 degrees off axis towards Siberia as it
| rotates within the earths core. In effect while it is rotating faster
| than the mantle, its axis of mass is also tilted off center by 10
| degrees and stretched slightly in the N-S axis. *This will in turn
| effect the equatorial rotation of the liquid inner core which acts as
| a boundary between the mantle and the solid inner core. Modeling the
| liquid core flow is always speculative for any model, but it is not
| unreasonable to assume that a 10 degree off axis solid core that
| rotates around its N-S center of mass could create a flow in the inner
| part of the liquid core that was also tilted in an equal but opposite
| 10 degrees `off axis` in the equatorial plane. Resulting in an equal
| and opposite tilt in the induced magnetic North pole of 10 degrees
| towards the Arctic, using Lenz and Fleming as described previously.
| This predicted tilt in the magnetic pole towards the arctic is
| consistent with observation. As is the prediction that the axis of the
| solid core is tilted towards Siberia.
| The final element is to explain the northerly drift of the magnetic
| North pole. There is insufficient seismic data to confirm or refute
| this prediction but the variable core speed model presented in this
| paper predicts that this would be due to an equal northerly drift of
| the solid inner cores rotational axis from more than 10 degrees off
| axis as currently observed to one that will be tilted by 0 degrees, or
| directly N-S. In other words if the solid core is said to be currently
| rotating tilted by 10 degrees off axis and this induces a off axis
| electrical current and off axis magnetic pole. Then a solid core that
| is aligned to earths geographic N-S axis as it rotates will generate
| no off axis electrical current and therefore no off axis magnetic
| field. In other words the cores volume is stretched in the N-S axis
| and tilted by 10 degrees but is changing shape as it rotates so that
| its N-S stretch is tending towards 0 degrees. In fact it would be more
| correct to say that its nvolume is changing from stretched 10 degrees
| off axis to not stretched in either the N-S or equatorial axis. This
| would be in line with a slowing down of the solid cores rotational
| speed as seen in the observed weakening of the overal magnetic field.
| (The variable speed core model predicts that when the core is
| perfectly circular in volume it rotational speed relative to the
| mantle will be the same as the mantle ,ie 0 degrees per year. And *no*
| magnetic field will be generated)
| The conclusion this `variable speed core` model makes is that all the
| combined observations of earths core and magnetic field indicate that
| the solid core is currently stretched in the N-s axis, tilted off
| center by 10 degrees and rotating faster than the mantle in an
| easterly direction by 0.1 degrees per year. But also observations
| indicate that it must be slowing down, relative to the mantle, tilting
| its axis more towards earths vertical N-S geographical axis, and most
| likely becoming less stretched in the N-S axis.
|
| Sean
| see this url for an accompanying graphic explanation of the variable
| speed core model...
|http://www.youtube.com/watch?v=CiCBrXKIH_0
|www.gammarayburst.com

You sure went to a lot of work and are to be congratulated on
the pretty pictures, but sadly this motor rotates in either
direction when the brushes are vertically aligned:http://cache.eb.com/eb/image?id=63375&rendTypeId=4
and you do not have any brushes.

Why do I need brushes in my model. The liquid core is connected
to itself. The current flows around it and doesnt need to be
connected to anywhere else by brushes .
And you havent made it clear why your diagram proves
that Lenzs law is incorrect. As far as Im aware an electrical
current always flows in the direction of the motion of the magnetic
field. At least thats what my reference indicates. For instance
if you have a solenoid arranged so that it is vertical on a
desk. If you then move a magnet south pole first downwards
into the top end,. the current in the solenoid
flows from top to bottom. The same occurs if the magnet
is reversed so that its north pole enters the top end of
the solenoid first and moves downwards.
But if you move the magnet either north or south pole first
upwards from the bottom of the solenoid then the current is
reversed in the solenoid. This is what any reference claims
is observed. It is this effect that I use to explain
how the current is induced in the liquid core.The outer
part of the liquid core rotates around the inner part
of the liquid core and induces a current in the same direction
as the mantles rotation relative to the solid core.When the
solid core slows it reverses the rotational direction between
the solid core and mantle which in turn reverses the flow
of the outer part of the liquid core. And that in turn reverses
the flow of the induced current in the inner part of theliquid
core.Which in turn ...etc (as Ive outlined elsewhere)


Whilst I can see where you are going with the core moving
relatively to the mantle, you haven't explained polarity reversal
or permanent magnetism. Core stretching is imagination stretching.
*http://space.rice.edu/IMAGE/livefrom/sunearth.html

No offense but this is incorrect.I have not imagined a stretching.
I have extrapolated from data a stretching and as I outlined
in the first post, there IS proof that the core is
stretched in the N-S axis. This proof is the data that shows
that sound waves travel faster in a N-S axis centered over
Siberia. And this is also consistent with my model in that
my model dictates that if the solid core is stretched over
siberia, as observed, then it would have to result in a
magnetic pole over the Canadian Arctic. And that too
is observed, not imagined.
Which permanent magnetism are you referring to?
If its the earths field then you have to look no further then the
experimental observations by others as cited above that show
that a rotationg liquid sodium can generate and sustain
a magnetic field with no outside input as long as it rotates.
Regarding your other point. In fact I have explained
the polar reversal. When the solid core widens at
the equator rather than the N -S axis it must by laws of
physics slow its rotational speed to that of slower than
the mantle. This means the core must reverse its motion
relative to the mantle resulting in the reversal
also of the liquid core rotation.
And Lenz and Fleming show us that this will
reverse the direction of the electrical current and thus
reverse the North South polarity.
In other words as Ive outlined in my first post and
at the animated explanation at..
http://www.youtube.com/watch?v=CiCBrXKIH_0
...the polar reversals are due to the reversals in the east west
rotational flow of the liquid core. Simple physics really.
Im surprised noone else thought of this before.


Sean
www.gammarayburst.com
http://www.youtube.com/profile?user=jaymoseleygrb