Structure of the Earth the crust, upper mantle, lower mantle, outer core, and inner core. The geologic component layers of Earth are at the following depths below the surface: The layering of Earth has been inferred indirectly using the time of travel of refracted and reflected seismic waves created by earthquakes. The core does not allow shear waves to pass through it, while the speed of travel (seismic velocity) is different in other layers. The changes in seismic velocity between different layers causes refraction owing to Snell's law, like light bending as it passes through a prism. Likewise, reflections are caused by a large
What the Bleep Do We Know!? "What the Bleep Do We Know!?" have described distinct assertions made in the film as pseudoscience. Lisa Randall refers to the film as "the bane of scientists". Amongst the assertions in the film that have been challenged are that water molecules can be influenced by thought (as popularized by Masaru Emoto), that meditation can reduce violent crime rates, and that quantum physics implies that "consciousness is the ground of all being." The film was also discussed in a letter published in "Physics Today" that challenges how physics is taught, saying teaching fails to "expose the mysteries physics has encountered [and]