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Originally Posted by glen chapman
Okay, I give up. You obviously have no idea what you are talking about, or any real understanding of geology. I better speak to some caver friends of mine, because with all this expansion going on, Jules Verne was right. The centre of the Earth is hollow. Will post photos when we get back.
Funny I used to think Creationist were a little odd....but
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The expanding Earth theory might seem odd, but that's mainly because it is not taught much in high school or university. But I can assure you it is a respectable theory that actually was a forerunner to plate tectonics. There was a period in the 60's where plate tectonics and EE vied for standing. Tuzo Wilson, one of the fathers of plate tectonics, actually supported EE for a while, and wrote on this in Nature. Expanding Earth theories fell by the wayside mostly because there was no clear cause of expansion. Plate tectonics (PT) also had no obvious cause, but because it did call for a change in size of the Earth it just became more acceptable. Scientifically, the evidence still supports EE. It's just not taught in school that way!
Before you discard EE completely, try reading Carey's books "The Expanding Earth" or "Theories of the Earth and Universe". Another good book is Pascual Jordan's "The Expanding Earth". Jordan favoured Dirac's idea that expansion is caused by a secular decrease in the gravitational constant G. There are also a lot of websites on EE now. Just punch in "expanding earth" in Google. The thread Expanding Earth Video also gives a sort of introduction, albeit a somewhat chaotic one.
The possible causes of EE can be briefly summed up as:
(1) expansion due to decreasing G (Dirac theory), which causes planets to elastically rebound and expand.
(2) expansion at constant mass and G, due to some sort of phase change in the core or mantle.
(3) expansion with increase of mass. This was favoured by Carey and some others. The question of course is where did the mass come from?
(4) expansion as a sort of scaled down version of the postulated universal expansion.
The proponents of expansion can't come to an agreement as to what the cause was, and so their case has not gathered much strength. But the absence of a proven mechanism for expansion does not mean that the reality of expansion has been negated. Expansion happened.
The point you made earlier about the thinning of atmospheres on expanding planets reminded me that if Mars was expanding at constant G and constant mass, it might still have been warmer in its early days due to its thicker atmosphere alone. The concentrations of greenhouse gases would have all been greater. It might thus not be critical here to postulate declining G to account for rain on early Mars.