Is inequality the cause of social unrest and the growing divisions among our citizens? See my most recent article in USA Today Magazine:
The equations describing the two-dimensional vortices first described by Chaplygin in 1899 and 1903 are shown to have solutions of higher order that differ from a simple dipole. It is also shown that for these higher-order vortices a very small asymmetry dramatically changes the topology of the stream function. These vortices could be important for understanding the phenomenon of atmospheric blocking.
This explains how to introduce a PolarStreamPlot into Mathematica. It was used for the streamline plots in this paper.
Variation in total solar irradiance is thought to have little effect on the Earth’s surface temperature because of the thermal time constant—the characteristic response time of the Earth’s global surface temperature to changes in forcing. This time constant is large enough to smooth annual variations but not necessarily variations having a longer period such as those due to solar inertial motion; the magnitude of these surface temperature variations is estimated.
Modern developments in nonequilibrium thermodynamics have significant implications for the origins of life. The reasons for this are closely related to a generalized version of the second law of thermodynamics recently found for entropy production during irreversible evolution of a given system such as self-replicating RNA. This paper is intended to serve as an introduction to these developments.
Dark matter, first postulated by Jacobus Kapteyn in 1922 and later by Fritz Zwicky in 1933, has remained an enigma ever since proof of its existence was confirmed in 1970 by Vera Rubin and Kent Ford by plotting the rotation curve for the Andromeda galaxy. Here, some concepts from string theory and topological change in quantum cosmology are used to formulate a new model for dark matter. The density profiles of dark matter halos are often modeled as an approximate solution to the Lane-Emden equation. Using the model proposed here for dark matter, coupled with previous work showing that the approximate solution to the Lane-Emden equation can be an exact solution of the Einstein-Maxwell equations, provides a new insight into the possible nature of dark matter.
Dolphin cognitive capabilities have been explored by investigating their neural anatomy, their social behavior in the wild, and by analysis of their complex vocalizations used for communication and environmental perception. After a brief introduction to dolphin hearing, sounds, and neurophysiology, and an even briefer discussion of sound propagation in the ocean, an analysis is given of some representative vocalizations. It is also shown that Mathematica offers a tool for easily synthesizing dolphin-like sounds that could be as basis for constructing a pidgin type language for human-dolphin communication.
This talk was given some time ago but remains relevant.
This book addresses the incentives to develop nuclear weapons, what it takes to do so, and some of the technical aspects of nuclear and ballistic missile programs. It uses the North Korean program as an example. It also addresses the associated policy issues.
To read the front matter through Chapter 1, click on the link below.
This book is an attempt to show the majesty of the immense journey from the coming into being of the universe to the emergence and evolution of life. While it begins with the birth of the universe and the subsequent formation of the matter making up the stars and planets, it is the four and a half billion years since the formation of our sun and its planets that are the main focus of the book.
Part I covers the coming into existence of the universe; Part II the beginning of life on the early Earth; Part III the emergence of consciousness and intelligence; and Part IV, the immense journey of the universe beyond Earth. Part V addresses the problems raised by the emergence of higher-order consciousness in human beings as captured by the phrase “the human condition”.
It has been suggested that the north-polar hexagon found on Saturn is an unusual Rossby wave. If this is to be the case, one must not only explain how a Rossby wave can be hexagonal in shape, albeit with curved corners, but also why it is hexagonal rather than in the form of some other polygon. It is likely that a spectrum of Rossby waves with different amplitudes and wavelengths resulting from the velocity profile of the hexagonal jet is responsible for its shape.
Link for Saturn video (3rd slide):