2021-10-18

The ultimate proposition of Geophysics: global scale quantum phase transition detected in the depths of the earth

By yqqlm yqqlm

The ultimate proposition of Geophysics: global scale quantum phase transition detected in the depths of the earth

researchers only have seismic fault images of this area. In order to interpret these images, they need to calculate the seismic (Acoustic) velocity of minerals under high pressure and high temperature. Through these calculations, they can create a three-dimensional velocity map and clarify the mineralogy and temperature of the observed area. When phase transitions occur in minerals (such as changes in crystal structure under pressure), scientists can observe velocity changes, usually a sharp seismic velocity discontinuity

in cooperation with a multidisciplinary team from Columbia Institute of engineering, University of Oslo, Tokyo University of technology and Intel, the latest paper by Renata wentzcovitch, a professor of Columbia Institute of engineering, describes in detail how they now determine the iron olivine spin cross signal, which is a quantum phase transition deep in the earth’s lower mantle. This is achieved by observing specific areas of the earth’s mantle expected to be rich in iron olivine. The study was published in nature communications on October 8, 2021

wentzcovitch said: “this exciting discovery confirms my earlier prediction and illustrates the importance of materials physicists and geophysicists working together to learn more about what is happening deep in the earth”

spin conversion is usually used for materials like magnetic recording. If you only stretch or compress a layer of magnetic material a few nanometers thick, you can change the magnetism of the layer and improve the recording characteristics of the medium. Wentzcovitch’s new research shows that the same phenomenon occurs thousands of kilometers inside the earth, bringing the phenomenon from the nano level to the macro level

The ultimate proposition of Geophysics: global scale quantum phase transition detected in the depths of the earth(1)

wentzcovitch also said: “in addition, geodynamic simulation shows that spin crossover activates convection and tectonic plate movement in the earth’s mantle. Therefore, we believe that this quantum phenomenon also increases the frequency of tectonic events such as earthquakes and volcanic eruptions”

researchers still do not understand many regions of the mantle, and the change of spin state is very important to understand velocity and phase stability. Wentzcovitch is continuing to interpret seismic fault maps using seismic velocities predicted by spontaneous calculations based on density functional theory. She is also developing and applying more accurate material simulation techniques to predict seismic velocity and transmission characteristics, especially in areas rich in iron, melting or near melting temperature

wentzcovitch said: “it is particularly exciting that our material simulation method is applicable to strongly related materials – multiferroic, ferroelectric, and generally high-temperature materials. We will be able to improve our analysis of three-dimensional tomographic images of the earth and learn more about how the crushing pressure inside the earth indirectly affects our life on the earth’s surface”