Exploring fundamental laws of classical mechanics via predicting the orbits of planets based on neural networks

Neural networks have provided powerful approaches to solve various scientific problems.Many of them are even difficult for human experts who are good at accessing the physical laws from experimental data.We investigate whether neural networks can assist us in exploring the fundamental laws of classical mechanics from data of planetary motion.Firstly,we predict the orbits of planets in the geocentric system using the gate recurrent unit,one of the common neural networks.We find that the precision of the prediction is obviously improved when the information of the Sun is included in the training set.This result implies that the Sun is particularly important in the geocentric system without any prior knowledge,which inspires us to gain Copernicus'heliocentric theory.Secondly,we turn to the heliocentric system and make successfully mutual predictions between the position and velocity of planets.We hold that the successful prediction is due to the existence of enough conserved quantities(such as conservations of mechanical energy and angular momentum)in the system.Our research provides a new way to explore the existence of conserved quantities in mechanics system based on neural networks.

Classical interpretations of relativistic precessions

Relativists have exposed various precessions and developed ingenious experiments to verify those phenomena with extreme precisions. The Gravity Probe B mission was designed to study the precessions of the gyroscopes rotating round the Earth in a nearly circular near-Earth polar orbit to demonstrate the geodetic effect and the Lense-Thirring effect as predicted by the general relativity theory. In this paper, we show in a very simple and novel analysis that the precession of the perihelion of Mercury, the Thomas precession, and the precession data （on the de Sitter and Lense-Thirring precessions） collected from the Gravity Probe B mission could easily be explained from classical physics, too.

Changes in Barents Sea Ice Edge Positions in the Last 442 Years. Part 2: Sun, Moon and Planets

This is the second paper in a series of two, which analyze the position of the Barents Sea ice-edge (BIE) based on a 442-year long dataset to understand its time variations. The data have been collected from ship-logs, polar expeditions, and hunters in addition to airplanes and satellites in recent times. Our main result is that the BIE position alternates between a southern and a northern position followed by Gulf Stream Beats (GSBs) at the occurrence of deep solar minima. We decompose the low frequency BIE position variations in cycles composed of dominant periods which are related to the Jose period of 179 years, indicating planetary forcings. We propose that the mechanism transferring planetary signals into changes in BIE position is the solar wind (SW), which provides magnetic shielding of the Earth in addition to geomagnetic disturbances. Increase in the solar wind produces pressure which decelerates the Earth’s rotation. It also transfers electrical energy to the ring current in the earth’s magnetosphere. This current magnetizes the earth’s solid core and makes it rotate faster. To conserve angular momentum the earth’s outer fluid mantle rotates slower with a delay of about 100 years. In addition will geomagnetic storms, initiated by solar coronal mass ejections (CMEs) penetrate deep in the Earth’s atmosphere and change pressure pattern in the Arctic. This effect is larger during solar minima since the magnetic shielding then is reduced. The Arctic may then experience local warming. The transition of solar activities to a possibly deep and long minimum in the present century may indicate Arctic cooling and the BIE moving south this century. For the North Atlantic region, effects of the BIE expanding southward will have noticeable consequences for the ocean bio-production from about 2040.