科普物理
The theory of lithopanspermia proposes the natural exchange of organisms between solar system bodies through meteorites. The focus of this theory comprises three distinct stages: planetary ejection, interplanetary transit and planetary…
The habitable zone is the circumstellar region in which a terrestrial-mass planet with an atmosphere can sustain liquid water on its surface. However, despite the usefulness of this concept, it is being found to be increasingly limiting in…
Before they met, David Bohm and Roger Penrose each puzzled over the paradox of the arrow of time. After they met, the case for projective physical space became clearer.
We consider some implications of the much-discussed circumstellar habitable zones around M-dwarf stars for the conventionally understood radio SETI. We argue that the flaring nature of these stars would further adversely impact local…
Abridged: The interest towards searches for extraterrestrial civilizations (ETCs) was boosted by the discovery of thousands of exoplanets. We turn to the classification of ETCs for new considerations that may help to design better…
Symmetry is a fundamental concept in modern physics and other related sciences. Being such a powerful tool, almost all physical theories can be derived from symmetry, and the effectiveness of such an approach is astonishing. Since many…
In this work we address the problem of estimating the probabilities of causal contacts between civilisations in the Galaxy. We make no assumptions regarding the origin and evolution of intelligent life. We simply assume a network of…
In this paper we have extended our previous work \citep{probe1} and considered spectral characteristics of interstellar non-relativistic Type-II and Type-III Von-Neumann probes. It has been shown that by means of the proton capture,…
I describe a simple method to calculate Earth dimensions using only local measurements and observations. I used modern technology (a digital photo camera and Google Earth) but the exact same method can be used without any aid, with naked…
The low temperature plasma technology has been emerged as an alternative environmental friendly technology that has a potential to replace the traditional technologies in various sectors such as textile industries, agriculture, food…
The ancient Chinese bridge, Luoyang Bridge, has been revealed to obey similar laws to diminish waves, like an optical model, metagrating. Numerical simulations have been performed to verify this finding.
It is well-known that the straight gravity tunnel between any two different positions on a non-rotating Earth, which has uniform density, is traversable, i.e., an object initially at rest will reach its destination through the gravity…
This paper is a celebration of the frontiers of science. Goodenough, the maestro who transformed energy usage and technology through the invention of the lithium ion battery, opens the programme, reflecting on the ultimate limits of battery…
Motivated by MacKenzie's observation of a negative force couple near to impact, this paper explores a model for how the golf club moves near to impact. It assumes the golf club is moving as the distal arm of a double pendulum. At impact the…
The ultralow frequency analogues of sound waves in Earth's magnetosphere play a crucial role in space weather, however, the public is largely unaware of this risk to our everyday lives and technology. As a way of potentially reaching new…
With the ever-increasing carbon footprint associated with conferences, scientists can learn to refine their conference experiences when they do need to travel. We offer insight on how to optimize the conference experience through attending…
Chirality, or handedness, is a topic that is common in biology and chemistry, yet is rarely discussed in physics courses. We provide a way of introducing the topic in classical physics, and demonstrate the merits of its inclusion - such as…
Space settlement represents a long-term human effort that requires unprecedented coordination across successive generations. In this chapter, I develop a comparative hierarchy for the value of long-term projects based upon their benefits to…
Using ideas of sphere packing problem we estimate the number of solid moons that can be packed inside the Earth, assuming that both the Moon and the Earth are perfect sphere.
The obscuration of a celestial body that covers another one in the background will be called a ``hierarchical eclipse''. The most obvious case is that a star or a planet will be hidden from sight by the moon during a lunar eclipse. Four…