Consider hydrogen for Earth's Core

[Moontanman]

My point Cold-co is why is the Earth so different than Mercury or Venus, why would the Earth have a cold hydrogen core? Because it spins? Where did the solid hydrogen come from? How would a solid hydrogen body form in the first place? Why would heat leave the cold core to make the mantle hotter? There are so many basic unanswered questions about a cold hydrogen core that are answered easily by the hot iron core model I see no reason to even consider your idea, then there the things Modest mentions, really overwhelming real problems. Personally I like to see the odd and or weird win a few battles but it does have to make some semblance of sense. If the most basic questions are not answered by your idea then it fails, adding all the other stuff to the mix is just obfuscation.

[CraigD]

From what I have read Mercury and Venus are close to being perfectly round because they are trapped in a syncronous orbit around the Sun and only rotate once in their year.

Although you’re correct that both Mercury and Venus are nearly spherical, Cold-co, I believe what you’ve either read very out-of-date astronomy texts, or misremember what you’ve read about the orbit and rotation of Mercury and Venus. More up-to-date information can be found innumerable places on the internet, including following the wikipedia links in this post.

 

The rotation characteristics of Mercury and Venus have been know with great precision since the early 1960s, when radar astronomy allowed direct observation of their surfaces.

 

Mercury’s rotation was a surprise, because prior to these observations, most astronomers that it would be tidally locked (synchronous) with the sun, with its sidereal day and orbital period the same. Instead, it was found to be in 3:2 resonance, rotating 1.5 times each 87.969 Earth day year. Mercury’s axial tilt, the least of any major solar planet, is close to zero, about 0.035° vs. Earth’s 12.4°

 

Venus is even stranger, rotating the opposite (retrograde) direction of its orbit at the slowest rate of any major planet, 1/248th the rotational rate of the Earth. Its axial tilt is also small, about 2.7°.

 

The lack of flattening of Mercury and Venus compared to Earth is almost certainly due to their much slower rotation.

 

However, the shape and rotation of Earth-like planets is, I think, a red herring (intentional or unintentional) when considering planetary differentiation (the separation of planets into different layers). The equatorial centrifugal force on a test particle within the Earth is at all depths very small, and even at the boundaries of its various deep layers (of which we know the depth with good precision via seismography), a small fraction of the force due to gravity. Although many important effects, especially their generated magnetic fields, would be much different if the Earth-like planets had much different rotations, no model I’ve seen or can plausibly imagine indicates that they would have differentiated much differently had, for example, Venus had Earth rotation, or vice versa.

[modest]

The lack of flattening of Mercury and Venus compared to Earth is almost certainly due to their much slower rotation.

 

Yes

 

This reminds me of something I heard once. In Einstein's original 1905 paper on special relativity he predicted quite reasonably that clocks on the equator would run slow relative to clocks on the pole due to relative velocity. But, this was not exactly correct. In general relativity clocks are also dilated with gravitational potential. Since the equator is some 22 kilometers further from the center of the earth than the pole, clocks on the equator are slowed by velocity yet sped up by relative difference in gravitational potential.

 

As it turns out, the two effects cancel exactly such that any clock anywhere on the earth at sea level will tick at the same rate as any other. But, this is no coincidence because in gtr every particle wants to find a path where its proper time is greatest. If earth were to become too spherical while spinning then parts on the surface would want to fall from the poles to the equator to maximize their proper time.

 

Assuming that the surface is in equilibrium as a surface of constant potential then the amount of bulge gives the rate of rotation.

 

In this way, the amount of the bulge can be given by the rate of rotation in both Newtonian gravity and gtr. Newton gave the first quantitative prediction in Prop. 19 and 20 of the third Principia at 1 part in 230. With better knowledge of the density of earth's inside layers the prediction becomes even more accurate. Using purely general relativity as derived here one gets approximately:

 

[math]b=\frac{r^4 \omega}{m}[/math]

 

where:

 

The mass of the Earth (in geometrical units) is m = 0.00443 meters, the angular speed of the Earth is w = (2.424)10^-13 rad/meter, and the nominal radius of the Earth is about r = (6.38)10^6 meters, so we estimate that the Earth's equatorial radius exceeds its polar radius by approximately 22,000 meters. This compares remarkably well with the best modern measurements of the Earth's actual equatorial bulge, which give the currently accepted value of about 21,476 meters (which is 1 part in 297.0).

 

The Bulging Earth

 

~modest

[stereologist]

I'm sorry, but as far as I'm concerned this forum of austute scientists did not debunk the cold-core model only wore the subject into the ground with obtuseness.

 

The unanswered question I had was simple. If you dig a deep mine and the earth is cold and the heat is due to the activity of mining, then the rocks pulled out of the wall should be colder on the side away from the mine. Cold-co claims to have worked deep mines. I wanted him to tell me where he made that observation.

[Pyrotex]

I'm sorry, but as far as I'm concerned this forum of austute scientists did not debunk the cold-core model only wore the subject into the ground with obtuseness.

Cold-co,

I'm really sorry. No doubt you have invested a lot of time and energy into your theory. And you've found a few books or websites that support your theory -- at least they appear to.

 

But we have done all we can to explain that the Cold Core Theory just cannot be supported by the evidence or by the known laws of physics. All we asked of you was to show us some evidence that could support it. Or show us how the laws of physics could support it. We would LOVE for you to be right!

 

But you never showed us any real evidence, and never showed us the laws of physics that support your theory. Indeed, you show no real understanding of physics at all. You made errors in your math. You made errors in your equations. You couldn't explain some of the symbols in the equations you had.

 

;) Again, I'm sorry. But that dog just won't hunt, cold-co. And if that makes US mean, obtuse, jerks... well, I don't know what can be done for it.