Structure of the Earth easily than does the upper mantle (chemical changes within the mantle may also be important). The viscosity of the mantle ranges between 10 and 10 Pa·s, depending on depth. In comparison, the viscosity of water is approximately 10 Pa·s and that of pitch is 10 Pa·s. The source of heat that drives plate tectonics is the primordial heat left over from the planet’s formation as well as the radioactive decay of uranium, thorium, and potassium in Earth’s crust and mantle. The average density of Earth is . Because the average density of surface material is only around , we must
What the Bleep Do We Know!? film has been described as an example of quantum mysticism, and has been criticized for both misrepresenting science and containing pseudoscience. While many of its interviewees and subjects are professional scientists in the fields of physics, chemistry, and engineering, several have noted that the film quotes them out of context. Filmed in Portland, Oregon, "What the Bleep Do We Know!?" presents a viewpoint of the physical universe and human life within it, with connections to neuroscience and quantum physics. Some ideas discussed in the film are: In the narrative segments of the movie, Marlee Matlin portrays Amanda, a photographer who