科普物理
This agile small "book" (in Italian) is an introduction to the life and work of Ettore Majorana, the brightest Italian theoretical physicist of the XX century, regarded by Enrico Fermi as the best theoretician of his time in the world. It…
What can we know about the universe? I outline a few of the fundamental limitations that are posed to our understanding of the cosmos, such as the existence of horizons, the fact that we occupy a specific place in space and time, the…
At any time, there are areas of science where we are standing at the frontier of knowledge, and can wonder whether we have reached a fundamental limit to human understanding. What is ultimately possible in physics? I will argue here that it…
When a mountaineer is ascending one of the great peaks of the Himalayas she knows that an entirely new vista awaits her at the top, whose ramifications will be known only after she gets there. Her immediate goal though, is to tackle the…
This paper summarizes two previously published technical papers describing what can be learned from measuring the motion of the golf club using two accelerometers. The sensors are mounted at different points along the shaft of the golf…
I outline a possible logical path from the formulation of physics of classical mechanics to "abstract" systems like cellular automata. The goal of this article is that of illustrating why physicists often study extremely simplified models,…
It is a remarkable fact that all processes occurring in the observable Universe are irreversible, whereas the equations in which the laws of physics are formulated are invariant under time reversal. The emergency of irreversibility from the…
Massive multiplayer online role-playing games (MMORPGs) are very popular in China, which provides a potential platform for scientific research. We study the online-offline activities of avatars in an MMORPG to understand their game-playing…
By using the Fermi satellite, a group of physicists discovers a new type of gamma-ray active nucleus
Proceeding like Newton with a discrete time approach of motion and a geometrical representation of velocity and acceleration, we obtain Kepler's laws without solving differential equations. The difficult part of Newton's work, when it calls…
Statistical analysis is a major aspect of baseball, from player averages to historical benchmarks and records. Much of baseball fanfare is based around players exceeding the norm, some in a single game and others over a long career. Career…
Even professional baseball players occasionally find it difficult to gracefully approach seemingly routine pop-ups. This paper describes a set of towering pop-ups with trajectories that exhibit cusps and loops near the apex. For a normal…
This is a review article about the most recent developments on the field of neutrino mass. The first part of the review introduces the idea of neutrino masses and mixing angles, summarizes the most recent experimental data then discusses…
We investigate whether storing baseballs in a controlled humidity environment significantly affects their aerodynamic properties. To do this, we measure the change in diameter and mass of baseballs as a function of relative humidity (RH) in…
A ball can be hit faster if it is projected without spin but it can be hit farther if it is projected with backspin. Measurements are presented in this paper of the tradeoff between speed and spin for a baseball impacting a baseball bat.…
A binary system of classical charged particles interacting through a dipole repulsive potential and confined in a two-dimensional hardwall trap is studied by Brownian dynamics simulations. We found that the presence of small particles…
We follow some (wild) speculations on trying to understand the uniqueness of our physical world, from the field concept to F-Theory.
We argue that the cosmic microwave background (CMB) provides a stupendous opportunity for the Creator of universe our (assuming one exists) to have sent a message to its occupants, using known physics. Our work does not support the…
A numerical model of 100 m and 200 m world class sprinting performances is modified using standard hydrodynamic principles to include effects of air temperature, pressure, and humidity levels on aerodynamic drag. The magnitude of the…
A geometric visualization is presented for the Brewster angle for a plane wave reflecting from an interface. The surface is assumed isotropic but it is allowed to display both dielectric and magnetic susceptibility, and hence the Brewster…