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The only one who is ignoring claims is you. Let's see what that site says (emphasis in italics mine) Origin of Basaltic Magma Much evidence suggests that Basaltic magmas result from dry partial melting of mantle. Basalts make up most of oceanic crust and only mantle underlies the crust. Basalts contain minerals like olivine, pyroxene and plagioclase, none of which contain water. Basalts erupt non-explosively, indicating a low gas content and therefore low water content. The Mantle is made of garnet peridotite (a rock made up of olivine, pyroxene, and garnet) -- evidence comes from pieces brought up by erupting volcanoes. In the laboratory we can determine the melting behavior of garnet peridotite. Under normal conditions the temperature in the Earth, shown by the geothermal gradient, is lower than the beginning of melting of the mantle. Thus, in order for the mantle to melt there has to be a mechanism to raise the geothermal gradient. One such mechanism is convection, wherein hot mantle material rises to lower pressure or depth, carrying its heat with it. This causes the local geothermal gradient to rise, and if the new geothermal gradient becomes higher than the initial melting temperature at any pressure, then a partial melt will form. Liquid from this partial melt can be separated from the remaining crystals because, in general, liquids have a lower density than solids. Basaltic magmas appear to originate in this way. This is sometimes referred to as decompression melting. From that site, here is a graphic that depicts the process described above: The only person who who lacks credibility here is you. You have used fallacies gallore and you have ignored evidence. You have repeatedly ignored my challenge to you asking you to explain the accumulated evidence behind plate tectonics.

Three sentences, each one of which is false. Nice going. You are still assuming that magma is completely molten. That simple is not true. You are still ignoring buoyancy, and that can be exert quite a large force. Finally, the thing that causes magma to become magma (partially molten rock) at the mid-oceanic ridges is not addition of heat. It results from the rock that will become magma rising and hence reducing in pressure. The rising rock carries some of the heat from the deep with it. When the rock mass rises high enough, the combination of reduced pressure and heat carried by the rock mass from the deeps causes the rock to begin to undergo a partial melt. This makes the rock even more buoyant, which makes it rise and melt even more. Even by the time the mass reaches the surface it is still only partially molten. That is exactly what geophysicists are trying to do. The explanation is not yet complete; that is why research can still be done in this field. (There is no field of science where the explanation is complete.) They are using the laws of physics. In comparison, you have offered nothing to explain these phenomena. I have challenged you multiple times to do so. You are taking what appears to be the standard crackpot approach to science. Crackpots try to show that the existing science is incorrect and then later (sometimes much later) introduce an alternative explanation. The attempts to disprove the existing science are typically full of fallacies (you get full marks here). The hidden agenda doesn't come out until much later (full marks again; you have yet to show your hidden agenda). Now, even if the crackpot is successful in stage 1, that does not mean that the alternate hypothesis is true. That alternate hypothesis has to undergo scientific scrutiny. Since you have not yet shown your alternate hypothesis I don't have anything to say about it. Hmm. Let's see exactly what I said in post #6. Does that look like I was proposing that science only be based on well-observed fact? I proposed nothing of the sort. What I did do was to ask you to explain those facts. I'm still waiting ... Science is a lot more than armchair philosophizing. It is nice but not essential to have a scientific theory have some theoretical basis. There is such a thing as an empirical science, a science based largely on observation. On the other hand, a scientific theory that does not comport with reality is a false theory no matter how pretty the theory is and no matter how good it looks from an armchair philosopher's perspective. Geophysics, BTW, is not one of those empirical sciences. Geology has moved from being an empirical science to one with a deeper theoretical basis thanks to geophysics.

OK, then. That is a very different question. The use of the term "lock step" and the discussion of Kepler's laws in the original post led me to think the topic of this thread was something very different than the long-term stability of the solar system. Whether the solar system is stable in the long term is an open question. Recent studies indicate that it may not be. There is apparently a small chance, about 1 percent, that a secular resonance between Jupiter and Mercury can make Mercury's orbit get so eccentric that its orbit crosses that of Venus. That in turn means there is a chance that Venus and Mercury could collide, and that in turn means all kinds of nastiness. Mars might even be ejected from the solar system. A recent paper on this subject: K. Batygin & G. Laughlin, "On the Dynamical Stability of the Solar System", The Astrophysical Journal, 2008, 683:2 1207-1216 ArXiv preprint: http://arxiv.org/abs/0804.1946 The June 2009 contains two short letters on this subject. The editor's overview, with links to the letters is at http://www.nature.com/nature/journal/v459/n7248/edsumm/e090611-06.html. (paysite)

Once again, I call bull. I suspect that is was you pointed out to your students that the stuff in the textbooks "was in violation of every physical principle". Just because you don't understand something doesn't mean it is wrong. Regarding the non sequitur you posted in the very first post in this thread, Too many teachers in the US come into the system with a bias against what they are teaching. This is particularly so in the south. You are a part of the problem.

Whoa! What "lock step"? This implicitly assumes to things, both of which are wrong. It assumes Kepler's laws say that there is some kind of "lock step" relation amongst the planets' orbits. It doesn't. It assumes Kepler's laws are absolutely correct. They aren't. They are approximately correct. They aren't even correct in terms of Newtonian mechanics, let alone general relativity. About item 1: "Lock step" would imply some kind of rational (e.g. 1/2, 2/3, ...) relation between the orbits of each of the planets. Numerologists try to pretend this is the case. As far as science can tell, it isn't. The Titus-Bode law is only approximately correct, and most likely, is only circumstantial. About item 2: Kepler's laws ignore a whole lot of things. It ignores that planets have non-zero mass. This means that Kepler's third law is only approximately correct, particularly so in the case of Jupiter. That the planets themselves have mass also means that the planets can and do perturb each other's orbits. Kepler's laws of course also ignore relativistic effects. (That omission is perhaps forgivable given that Kepler predated Newton by a generation and Einstein by hundreds of years.) Predicting the planets' locations based on Kepler's laws alone is not going to give accurate positions for any length of time--and certainly not billions of years. There is no good prediction scheme for that kind of time scale. The solar system is chaotic with a Lyapunov time of 5-10 million years.

I call bull. Or rather, I call crackpot. Everything you have posted here is screaming "crackpot". If you don't want to give that perception perhaps you should change your style. Emphasis mine: Thanks for reminding me that science is not about observation. A clue for you: Science is all about observation. It was observations, for example, that led to the development of the theory of evolution and quantum mechanics -- and of modern geology. The observation of the mid-oceanic ridges, coupled with the observation of the increased age of the oceanic crustal rock with increased distance from the mid-ocean ridge, was the driving factor that led to the development of plate tectonics. Modern geology has explained those phenomena to a remarkable extent given that modern geology is only about 50 years old. The discovery of the mid-oceanic ridge marks the birth of modern geology. Just because you say so doesn't mean that it is true. Prove it. Wrong. You are implicitly assuming that the magma melts completely and abruptly. That simply is not the case. The fraction of material in magma that is melted increases as the magma rises. Even erupting lava is not fully melted. You are also ignoring pressure and buoyancy here. Once again, just because you say so doesn't mean that it is true. You haven't answered a thing. All you have offered are ill-formed opinions about the existing explanations. You have offered no explanations of your own. I'll challenge you once again: how do you explain: The well-observed fact that there is a 60,000 mile long series of mid-oceanic ridges that girdle the globe. The well-observed fact that plates are moving apart from one another along these mid-oceanic ridges. The well-observed extrusion of magma at several sites along the mid-oceanic ridge. The well-observed magnetic striping of the sea floor, with the stripes parallel to the the mid-oceanic ridges. Do keep in mind that science is first and foremost about explaining observed phenomena. First off, your link doesn't work. Please check that your links work in the future. Secondly, if you had gotten the link correct it would have linked to a pay site. That's not nice. Here is a link to the full article: http://adsabs.harvard.edu/full/1982AREPS..10..397T This article is 30 years old. Whether ridge-push and slab-pull is the dominant process at the mid-oceanic ridges was not known back then and remains an open question. Note well: Just because there are open questions in some science does not mean that the science is questionable. It just means that the science does not have all the answers -- yet. That's a good thing, not a bad thing. It means that work remains to be done, papers remain to be published. A science that has all the answers would be rather boring.

By the same reasoning, the Coulomb force isn't a force either. A point charge creates an electric field and the so-called Coulomb force isn't really a force, it's just a name we give to the product of the electric field and the charge on a test particle. So, Bzzzt. Wrong. Gravity is a weird beast. Gravitation is a fundamental force in Newtonian mechanics but it is a fictitious force in general relativity. If your teacher acquaintance had talked in this way I would have agreed with him. This topic can be discussed without going into the mathematical details. (The mathematics of GR is are way over the head of most undergraduate physics majors, let alone high school students.) The focus of this non-technical discussion would be the equivalence principle and the concept of weight. Weight, like gravity, is also a weird beast. Weight defined as gravitational acceleration times mass cannot be measured. What your bathroom scale measures is apparent weight rather than actual weight. In Newtonian mechanics, apparent weight is the net sum of all real (non-fictitious) forces acting on an object except for gravity. In general relativity, apparent weight is the net sum of all real (non-fictitious) forces acting on an object, period. Gravity is a fictitious force in GR.

Crackpot. Very nicely presented, but crackpot nonetheless. There is no lunar time-scale problem. Let's look at the author's own numbers. The author stated a current lunar recession rate of 1.5 inches/year. The Permian–Triassic extinction event occurred 251.4 million years ago. A linear extrapolation of that current rate says the Moon would have been 6000 miles closer to the Earth at the time of that extinction event, or 233,000 miles distant (the distance between the centers of the Earth and Moon is currently 239,000 miles). So, the theory is an absolute no go assuming that the Moon has been receding at a constant rate of 1.5 inches/year for the last 250 million years. It turns out that is not a good assumption. The current recession rate is abnormally high, which in turn means that the above 6,000 mile figure is high. The average recession rate is about half the current value. At the time of the P-T extinction the Moon was about 236,000 miles from the Earth. The Roche limit for a body the size and density of the Moon with zero tensile strength is about 12,000 miles. The reason the current recession rate is abnormally high is because the of the current configuration of the continents. There are two north-south barriers to a world-girdling tidal flow. The Americas present a solid land barrier from 56°32′ south to 71°58' north while Africa and Eurasia present a solid land barrier from 34°51' south to 77°44' north. The configurations of the continents also arise in resonances that accentuate these barrier effects. Finally, and most damning, the hypothesis disagrees with observation. There is a very good historical record of the number of days per month and number of months per year frozen in various fossils and rock formations. This record now goes back to 3.2 billion years ago. The length of a day and the distance between the Earth and the Moon can be determined from this record. The only conclusion that can be drawn from this record is that Moon has been orbiting the Earth for at least the last 3.2 billion years. The most widely accepted theory of the Moon's formation is that it was indeed captured (by means of collision), but this occurred 4.5 billion years ago, not 250 million.

... and you're not off to a good start. Use of fallacies is strongly forbidden at this site. The title of the thread uses of scare quotes around physics, implying there is no physics in geophysics. So, fallacy #1, appeal to ridicule. Fallacy #2: Another appeal to ridicule, this one a lot more out in the open than the scare quotes in the title. Fallacy #3: Non sequitur. The cited article has nothing to do with geophysics. Fallacy #4: Red herring. This is a misrepresentation of plate tectonics. Fallacy #5: Composition fallacy. Magma is not partially molten and is not fully expanded. Fallacy #6: Bare assertion. Just because you say something is so doesn't mean it is so. I don't know what your hidden agenda is here. Don't keep it hidden: Why don't you just come out with it? How do you explain The well-observed fact that there is a 60,000 mile long series of mid-oceanic ridges that girdle the globe. The well-observed fact that plates are moving apart from one another along these mid-oceanic ridges. The well-observed extrusion of magma at several sites along the mid-oceanic ridge.

If by that simple statement you mean that there exists one unique reference against which all things can be judged, nope. Theory and observation say that this simple statement is simply wrong. There is no preferred reference frame.

There are two common mistakes high school students and freshmen make in solving these kinds of problems. Since your exponent is way off its hard to tell. These mistakes are Not using the correct value for G, the Earth's mass, etc. G is 6.673×10-11 m3/kg/s2. Note well: G has units. It is a physical constant. Solar system astronomers might well use 1.488×10-34 AU^3/kg/day^2. Treating physical constants such as G and physical values such as the Earth's mass and the Earth-Moon distance as numbers. Don't do that! The number one sign that students are doing that is stating the result without units. Always carry the units along with you in your calculations.

That "one single undeformed reality" doesn't exist. It is those measurements that are real -- and yes, they sometimes are apparently contradictory. So be it. That is the universe in which we live.

What do you mean by that? It is pretty obvious from the underlying mathematics that repulsive forces cannot result in closed paths.

What precisely do you mean by this statement? You need to be very careful here. You risk falling into the same kind of nonsense that ensues from people who do not understand the uncertainty principle. That's the same crap you posted in #27. And it is crap. There is no way to trace the Earth back to 4.5 billion years ago through crustal markers. The Earth was molten 4.5 billion years ago. The Earth had to cool for 400 million years before the crust formed. His amazingly precise results, a radius of 6956 kilometers 4.5 billion years ago and an outgassing of 3.22×1025 grams of hydrogen, are signs that this is utter nonsense. Those are numbers pulled out of a lower body orifice. Another sign of nonsense is the statement "Average compression speed of our planet was 1.46x10-2 cm per year." The shrinking, if it did exist, would have be anything but uniform. It would have been much closer to exponential. Using an average rate to describe an exponential process is bad form at best. This has the look and feel of crackpot analysis. A word of advice: Don't put much credence in what Russian biologists and geologists say. Several sciences, and those two in particular, suffered immensely in the old Soviet Union. Russia is still recovering from the damage done by communist ideology to those sciences. Twenty years is not near enough time to undo that damage. It stands to reason that the Earth did indeed shrink somewhat in the last 4.5 billion years. It also stands to reason that the vast, vast majority of that shrinkage occurred shortly after the Earth formed. Some of that initial shrinkage resulted simply from cooling. Cooling is roughly an exponential decay process. Most of the cooling occurred during that first 400 million years when the Earth was still molten. Another factor is gravitational collapse. Most of that happened prior to 4.5 billion years ago. The outgassing? We don't know enough about planet formation or about early planetary chemistry to be able to say anything close to a number as precise as "3.22×1025 grams of hydrogen." There are some secondary effects that did happen after that initial cooling. It took quite a whole for the Earth's solid core and post-perovskite layer at the core-mantle boundary to form. Scientists still don't know enough about either of those, and particularly about the post-perovskite layer, to be able to say anything precise about how those affected the size of the Earth. These are secondary effects, however. The vast majority of the shrinkage occurred very early on in the Earth's history.

Very, very minute. That -100 meter level in the geoid height to south of India represents a reduction of about 0.006% in gravitational acceleration compared to the nominal level for that latitude.

You need to read the list of cases that Pangloss cited. The third one is particularly relevant here (emphasis mine): Fifteen years later, in 1999, the United States Court of Appeals for the Tenth Circuit reaffirmed its position, in United States v. Vasquez-Alvarez, 176 F.3rd 1294, stating, “this court has long held that state and local law enforcement officers are empowered to arrest for violations of federal law, as long as such arrest is authorized by state law.”

Yes and no. Euler's method is essentially first order Runge-Kutta. Consider second-order Runge-Kutta, one step above Euler. Two commonly used second-order Runge-Kutta integrators are the midpoint method and Heun's method. The midpoint method is [math]y_{n+1} = y_n + \Delta xf(x_n+\Delta x/2, y_n+ \Delta xf(x_n,y_n)/2)[/math] The Butcher's tableau for the midpoint method is 0 | 1/2 | 1/2 ----+--------- | 0 1 Heun's method is given by [math]y_{n+1} = y_n + \left(f(x_n,y_n) +\frac 1 2 \Delta x f(x_n+\Delta x,y_n+\Delta xf(x_n,y_n))\right)[/math] The Butcher's tableau for Heun's method is 0 | 1 | 1 ----+--------- | 1/2 1/2 Neither is optimal in the sense of minimizing truncation error. The second-order Runge-Kutta technique that minimizes truncation error is given by the tableau 0 | 2/3 | 2/3 ----+--------- | 1/4 3/4 Now, if second-order Runge-Kutta can offer so many choices (there are an infinite number), you can just imagine how messy higher order techniques can get. This article at wolfram.com describes some of the issues: http://reference.wolfram.com/legacy/v5_2/Add-onsLinks/StandardPackages/NumericalMath/Butcher.html. That said, here are some links describing 10(8), 12(10) and 14(12) Runge-Kutta integrators: http://www.mathworks.com/matlabcentral/fileexchange/25291-rkn1210-a-12th10th-order-runge-kutta-nystrom-integrator http://sce.uhcl.edu/rungekutta/ http://sce.uhcl.edu/rungekutta/GlascowRK.ppt (powerpoint)

16 out of 20 people in my betting group (for a win by Chile' date=' not necessarily the exact result).[/quote']I don't think Rickdog was talking about Chile v. Honduras when he asked "who'd imagine it ..." That Chile would beat Honduras was the expected result. That the Swiss would beat the Spaniards -- that was a Swiss pipe dream. Sometimes one's dreams do come true!

Yep. So much for the FIFA rankings. Past performance is not necessarily indicative of future success. Merged post follows: Consecutive posts merged It looked very non-deliberate to me. You have to remember that the foul is not handball. That a player touched the ball with his hand (which in soccer starts just below the shoulder) is not enough. The name of the foul is handling the ball. The touch has to be made with intent. The referee has to try to read the player's mind. One obvious way to intentionally handle the ball is to swat it down and gain advantage off of the bounce. The Hand of God goal, for example. Doing this requires some distance between the kick and this kind of intentional handling of the ball. As spectacular as pros are, even they have limitations on reaction time. There is no way that even the best player can intentionally smack down a ball kicked at pace from a short distance away. That said, a player could stick his hands out and hope that the ball will hit his hands -- and that too indicates intent. When inside the penalty box, a defensive player has to go out of his way to indicate he did not intend to handle the ball. In this case, Mertesacker appeared to be acting properly. His hands were not intentionally placed in the way, and he tried to get them out of the way from a ball kicked at pace from a short distance. The contact was incidental; no foul. As far as the red card for Cahill: Prior to the onset of every World Cup, FIFA announces to the refs and to the rest of the world those behaviors that FIFA very much wants not want to see. Last time around it was simulations. This time it is serious fouls. Too many players have been injured lately from tackles from behind. Late tackles from behind have always been noted as a serious foul in the rules but refs have not always treated them as such. This time around the refs were notified to watch for such fouls. Cahill made a late tackle from behind. Red card.

While detailing the causes of plate tectonics remains a work in progress, the basic mechanisms are fairly well understood. The key underlying mechanisms are heat transfer and gravity. A shrinking Earth is not a part of the picture. You are the one proposing a new model, so you are the one who needs to explain why this new theory is needed. What problems does your model fixing? What predictions does your model make that distinguish it from the existing model? Does your model agree with known facts? What are the theoretical underpinnings of your model?

Except that what you are claiming is not true. A day was considerably shorter 4.5 billion years ago than it is today, perhaps as short as six or so hours long. The length of a day has increased since then and continues to increase to this day. A day was about 15 hours long 3.8 billion years ago, 18 hours long 900 million years ago, 22 hours long 400 million years ago. I agree with that, but not for the reason you cited.

Then why do you argue with it? What causes the plates to move, the upwelling and downwelling at boundaries? What causes vulcanism? You misunderstand what I and others have said. Suppose that the cited study showed that the Earth's radius 400 million years ago was 102±0.28% of today's radius (instead of the cited 102±2.8%). The null hypothesis would then have to be rejected were that the case. The null hypothesis cannot be rejected on the basis of the actual study because no change (100%) is within the uncertainties of the results.

Beat me to it!

The conclusion I would draw from the first reference is that the null hypothesis cannot be rejected. The null hypothesis here is that the Earth has neither expanded nor contracted over the last 400 million year. The second reference, which you have ignored, is a much more stringent test. No significant change in the Earth's radius has changed over the last 620 million years. It does stand to reason that the Earth has changed shape/size to some extent over the last 4.5 billion years (i.e., since the formation of the Moon). The Earth was much hotter way, way back then than it is now and the Earth was rotating much faster then than it is now. It also stands to reason that the vast majority of whatever gross changes in size/shape did take place occurred very, very early in the Earth's history. That very early shrinking does not explain the shape of the continents and it does not explain plate tectonics. Plate tectonics is driven primarily by the continued cooling of the Earth, not by the more-or-less stagnant gross size/shape of the Earth. By way of analogy, think of heating a pot of water on a stove to near boiling. You can see a lot of roiling and eddies in that nearly-boiling pot of water. While the water does expand very slightly due to that heating, that slight expansion does not explain all the turbulence you are seeing. Heat transfer does.

No. That water can exist in all three states in Earth's atmosphere plays a major role in the formation of clouds in the Earth's atmosphere. You wouldn't expect to see water clouds on Venus (no water) or on Pluto (too cold). Clouds on Venus are composed of carbon dioxide and sulfuric acid; clouds on Pluto are composed of nitrogen and carbon monoxide. The critical temperatures of N2 and O2 are 126K and 155K, respectively. One will not see clouds of nitrogen or oxygen gas because nitrogen and oxygen remain gases throughout Earth's atmosphere. It has nothing to do with hydrogen bonds. One might well expect to see clouds of nitrogen on a very cold planet such as Pluto, and that is precisely what is seen there. For example, see http://www.sciencenews.org/view/generic/id/50424/title/Plutos_cloud_components_verified_.