科普物理
Why do curling stones curl? That is a question physicists are often asked, yet no answer has been established. Stones rotating clockwise curl right, contrary to our naive expectations. After a century of debate between contradicting…
Christopher Nolan's latest blockbuster, Interstellar, has supposed a revolution not only from a cinematographically viewpoint, but also in the relation between current spectators and science. The aim of this report is to analyze some…
If a civilization embarks on high-speed intergalactic expansion, growing to a cosmological scale over time, communication between remote galaxies in the civilization will incur an extreme time delay, due to the distance involved. Indeed, if…
In the present manuscript we consider the possibility of SETI by the small size (with diameters less than 1 m) optical telescopes. Calculations are performed for typical parameters of the mentioned type of telescopes. In particular, we show…
Deep space exploration offers the most profound opportunity for the expansion of humanity and our understanding of the Universe, but remains extremely challenging. Progress will continue to be paced by uncrewed missions followed up by…
The torque-free motion of rigid body in gravitational field is analyzed. The coin lands on a soft surface (such as the palm of the hand) that allows no bouncing. The model assumes the coin as a rigid body with constant angular momentum…
We present what we know on nucleosynthesis in the Universe and hypotheses that have been made in this regard. A brief description of the Universe's evolution during its different stages is offered, indicating which are the periods and…
Brief recollections by the author about how his work with Kip Thorne influenced his career in physics.
Paper strips, e.g. confetti, descending to the floor begin to rotate around the horizontal axis after a short time. This slows down the vertical velocity compared to free fall and adds a horizontal velocity component. The frequency of…
A series of ceramic artworks are presented, inspired by the author's research connecting theoretical physics to the beautiful theory of Riemann surfaces. More specifically the research is related to the classification of curves on the…
A novel approach to velodrome design for UCI-regulated tracks is presented. The mathematical model uses differential geometry to form a three-dimensional ruled surface. The surface accounts for the safety zone, blue band, and track region,…
Oscillation and collective behavior of diffusion flames is a fascinating phenomena. Considering candle bundles with different sizes in variable oxygen concentration, the flickering dynamics of the flames are experimentally and theoretically…
What is the most effective way to grill food? Timing is everything, since only one surface is exposed to heat at a given time. Should we flip only once, or many times? We present a simple model of cooking by flipping, and some interesting…
Till now there is no solid scientific proof for any of the numerous hypotheses proposed for the Tunguska 1908 event. Regarding the most popular "spacebody infall" interpretation it is reasonable to compare the Tunguska event with the 2013…
For millenia, sailors have used the empirical rule that the elevation angle of Polaris, the North Star, as measured by sextant, quadrant or astrolabe, is approximately equal to latitude. Here, we show using elementary trigonometry that…
Slinkys that start from a stretched equilibrium position supported at the top and then released to fall under the influence of gravity exhibit the interesting behavior that the bottom of the slinky does not move until the collapsing top of…
Fluctuations are ubiquitous in nature. They are one of the fundamental building blocks of quantum mechanics and are responsible for a wide variety of phenomena in many areas of physics, ranging from biology to cosmology. Far from any…
Antimatter is one of the most fascinating aspects of Particle Physics and one of the most unknown ones too. In this article we concisely explain what is antimatter and its distinction between primordial and secondary, how it is produced,…
Very simple experiments based on an analogy between two theories (gravitation and capillarity) allowed us to construct a two dimension space toy-universe composed of the surface of a three-dimensional water tank with floating soap bubbles…
How aesthetically pleasing is your country's diffraction pattern? This work summarizes the calculated and experimental Fraunhofer diffraction patterns obtained from using apertures lithographically formed into shapes of national borders.…