I find David's theories to be interesting and insightful. Here's a piece I wrote a while back about my theories on the earth/sun relationship.
Feel free to pick it apart....

Earth Dynamo Theory

I've always been curious about earth's polar shifts, and have been studying the effects of the sun on our magnetosphere, especially during solar maximums such as the one we've been going through. I've come to believe magnetic pulses from the sun affect earth's inner cores rotation.

Earth is like a self-exciting dynamo, receiving pulsed energy from the sun, spinning like a top with positive and negative magnetic poles and a spinning core. Like a dynamo, the rotation through a magnetic field causes an electric potential difference between its inner and outermost area. This potential difference causes discharges of energy to occur from the ionosphere to the earth in the form of lightning. Lightning is plasma, pure electromagnetic energy.

Coronal bursts from the sun cause the earth's inner core to spin faster, causing the magma to heat from friction, resulting in increased pressure and heat within the earth. This pressure causes movement of the tectonic plates, resulting in earthquakes and volcanic activity. The heat from the inner friction warms our oceans, causing El Nino's to form and ice shelves to retreat. The suns magnetic bursts also cause earth's magnetic field to drift. The minerals in the earths crust attempt to align themselves with the
field, and additional tectonic plate movement results.
Here are some facts:
From space sensors and probes, we know that the sun is made up of different quadrants of alternating magnetic polarity, and that the poles rotate at different speeds than the equator. The alternating fields tangle and cause magnetic loops to form. We see sunspots. Occasionally they collapse and explode with energy, sometimes with huge amounts toward our planet known as full halo coronal mass ejections ("http://www.spaceweather.com") . When the magnetic energy reaches our planet, it enters our magnetosphere. We call it Aurora Borealis, and see the charged particles glow colorfully when they interact with the various elements in the earths atmosphere. Interestingly enough, earths own lightning discharges into our magnetosphere when it's not streaming down to earth.
Also from NASA, we know that the sun goes through an 11-year solar maximum cycle, during which time it exhibits increased magnetic explosion activity, and it appears to have even longer cycles based on sunspot data. As the energy strikes our planet, it peels away the impact area of our magnetosphere like the layers of an onion. Our field is pushed away from the suns energy, its magnetic lines stretched back until the pulse wave has passed, at which time the field collapses back in on itself pouring energy
into the earth. Other particles from the sun bombard our planet such as neutrinos, which have just recently been proven to have mass. In addition, the energy charges our ionosphere, and we see impacts on radio wave transmission and power grids.
We know that earth's magnetic field has reversed polarity many times in the past. We can tell this from the polarity of elements in lava flows from volcanoes, as they align themselves with the polarity of the planet at the time they cooled. We also know from monitors that our earth's field is affected by the suns activity, and that it shifts by several degrees during a heavy solar storm. We know that earths crust is made up of several plates, which drift on molten rock. When the plates push under one another, this molten rock is ejected through volcanoes, and earthquakes occur on the brittle edges. The "Ring of Fire" in the Pacific Ocean is a huge ring of volcanoes lining the pacific tectonic plate.
We know that many of earths deserts used to be oceans, and that many sections of the ocean floors were deserts and land. It would appear that the plates raise and lower, in addition to drift.

The Maya believed the sun has destroyed the earth 4 times in the past, and that the end of the fifth sun was going to occur in 2012. That falls on an 11-year cycle. Unfortunately, Cortez melted down most of the Mayans calendars and documents for their gold content so we can't learn much more, but that's another story. What if earth's polar shifts occur in sympathy with the suns magnetic field reversals, like a piano string vibrates when a pitchfork is held close?
What happens to the earth's electrical potential difference between the ionosphere and ground when a polar shift occurs? Does it reverse so that negative becomes positive, and lightning strikes upward from the ground? What happens to gravity in the process? Regardless of popular belief, we don't understand mass, let alone gravity. Scientists are working with a supercollider in 2001, as this is being typed, to try and understand what makes a molecule of lead heavier than a molecule of air.

Billion Watts
http://www.billionwatts.com