All posts under category "Physics / Physics.hist-Ph"
We review the non-trivial issue of the relativistic description of a quantum mechanical system that, contrary to a common belief, kept theoreticians busy from the end of 1920s to (at least) mid 1940s. Starting by the well-known works by Klein-Gordon and Dirac, we then give an account of the main res
Sunspot observations with telescopes in 18th century were carried out in Japan as well. One of these sunspot observations is recorded in an account called Sansaizusetsu narabini Kansei irai Jissoku Zusetsu (Charts of Three Worlds and Diagrams of Actual Observations since Kansei Era). We analyze manu
In this paper, we discuss the role of Mathematics in articulating reality in theoretical Physics. We propose a parallel between empirical and theoretical work and investigate how scientists can also speak about reality without performing any laboratory trial, a key explanation element of STS. To do
It is seldom acknowledged the tremendous burden that the Nuclear Age leaves on future generations, and the environment, for an extremely long time. Nuclear processes, and products, are activated at energies millions of times higher than the energies of chemical processes, and consequently they canno
We review the definition and the concepts of the weak values and some measurement model to extract the weak value. This material is based on the author Ph.D. thesis 'Time in Weak Values and Discrete Time Quantum Walk' at Tokyo Institute of Technology (2011).
I make the case that the Universe according to unitary (no-collapse) quantum theory has a branching structure, and so can literally be regarded as a 'many-worlds' theory. These worlds are not part of the fundamental ontology of quantum theory - instead, they are to be understood as structures, or pa
This paper celebrates the remarkable life, science and legacy of Abb'e Georges Lema^itre, the Belgian cleric and professor of physics; he was the architect of the fireworks model for the origin of the universe. He died half a century ago, three days after learning that Arno Penzias and Robert Wilson
Dmitri Ivanenko, professor of Moscow State University, was one of the great theoreticians of XX century, an author of the proton-neutron model of atomic nucleus. In honor of the 110th Year Anniversary.
A scientific introduction and short biography to accompany the translation of Matvei P. Bronstein, 'Quantum theory of weak gravitational fields', Phys. Zeitschr. der Sowjetunion 9, 140 157 (1936), to appear as a 'Golden Oldie' in JGRG.
The classical method for measure the Earth-Sun distance is due to Aristarchus and it is based upon the measure of the angle Moon-Earth-Sun when the Moon is exactly in quadrature. Such an angle is only 9 arcminutes smaller than 90 degrees, and it is very difficult to evaluate, being necessary to look
Two important and unpleasant events occurred in Albert Einstein's life in 1920: That August an antirelativity rally was held in the large auditorium of the Berlin Philharmonic, and a few weeks later Einstein was drawn into a tense and highly publicized debate with Philipp Lenard on the merits of rel
The cosmic ray conference at Bagn`eres de Bigorre in July, 1953 organized by Patrick Blackett and Louis Leprince-Ringuet was a seminal one. It marked the beginning of sub atomic physics and its shift from cosmic ray research to research at the new high energy accelerators. The knowledge of the heavy
Claude Francis Milliet Dechales described the Coriolis effect in his 1674 Cursus seu Mundus Mathematicus. Dechales discussed and illustrated the deflection of both falling bodies and of projectiles launched toward the poles that should occur on a rotating Earth. Interestingly, this was done as an ar
The 1927 discovery of the expansion of the Universe by Lemaitre was published in French in a low-impact journal. In the 1931 high-impact English translation of this article a critical equation was changed by omitting reference to what is now known as the Hubble constant. That the section of the text
A brief description and results of A.M. Mathai's research programme on statistics and probability, initiated in the 1970s, and its relation to physics is given.
When guns were developed in Europe in the 14th century, the theory of projectile motion was not the one we are familiar with today due to Galileo and Newton but the one taught by Aristotle approximately 1700 years earlier. In addition to Aristotle's wide-ranging philosophical concerns, his theory ar
In this paper we discuss the orientation of the Egyptian pyramids at Giza with respect to sunrises and sunsets, using SunCalc.net software. We can see that Khufu and Khafre pyramids had been positioned in a manner that, from each pyramid, it was always possible to observe the points of the horizon w
Enter keywords to search articles