The fine-structure constant

Arnold Sommerfeld

One of the latest scientific advances of 2020 was a new, more precise measurement of the fine-structure constant. The last value officially accepted in 2018 by the Committee for Data on Science and Technology (CODATA) is equal to 1/137.035999084. The value obtained in December 2020 is equal to 1/137.035999206. It will be seen that the difference with the previous value is very small and affects only the seventh decimal place.

But what is the fine-structure constant? It's a dimensionless constant, defined by the following formula:

Dating the Turin Shroud

Comparison of positive (left)
and negative (right) photos

The Shroud of Turin (or Sindone, from the Greek σινδών, shroud) is traditionally thought to be the shroud that covered the body of Christ during the three days that he was buried between his death on the cross and his resurrection. The documented part of its history begins in 1357, when it was exhibited for the first time in Lirey (France). In 1453 it was sold to the Duke of Savoy. In 1532 it was damaged in a fire, and in 1578 was transferred to Turin, where it is located today. Although the Catholic Church allows its veneration, it has never pronounced either in favor or against the authenticity of the Shroud, which from the beginning was the subject of controversy, as some claimed it was a contemporary painting, while others considered it authentic.

In 1898 the Shroud was photographed for the first time and the image was found to be much sharper on negatives than on positives, so the original image appears to be roughly equivalent to a photographic negative.

Is there a crisis in theoretical physics?

Nicolaus Copernicus

Physics has been, for the last seven centuries, the queen of sciences: its object is the study of the lowest-level of reality; its most akin to mathematics; it has seen happen the highest number of new, spectacular and revolutionary theories and discoveries. Let's see a few of them:

• 13th century: Roger Bacon studies reflection, refraction, spherical aberration and the use of lenses to correct vision defects. He also suggests the possibility of building telescopes, microscopes, and flying vehicles.
• 14^th century: Jean Buridan, Nicolás Oresme, Albert of Saxony and the calculators of Merton College revolutionize Mechanics, separating it for the first time from the work of the Greek philosophers, and introducing new concepts such as impetus.
• 16th century: Copernicus proposes replacing Ptolemy's geocentric system by a much simpler heliocentric system. Kepler modifies the theory of Copernicus and discovers the three empirical laws that bear his name.
• 17th century: Galileo perfects the telescope and makes with it astronomical discoveries. He also recapitulates and organizes the mechanical discoveries of the 14th century. Newton revolutionizes physics with the theory of universal gravitation, which unifies terrestrial and celestial mechanics, and makes great advances in optics. Other important physicists of that century are Pascal, Huygens, Boyle, Mariotte, and many more.
• 18th century: Although it's possible to detect a certain slowdown in scientific research, we can mention the Bernoulli brothers, and near the 19th century, Galvani, Volta and Laplace.
• In the 19th century, discoveries in theoretical and experimental physics and the number of professional physicists increased dramatically. Let's mention just a few of the most important: Dalton, Faraday, Ampère, Gauss, Maxwell, Carnot, Lord Kelvin and Boltzmann.

Influence of aesthetic ideas in physics

The Birth of Venus by Botticelli

In a previous post I reviewed the new book in Spanish by Francisco José Soler Gil, entitled The enigma of the natural order. Its third chapter, whose title is Aesthetic ideas in physics, which reproduces a lecture given by the author at the Faculty of Chemistry of the University of Seville, has provided me with matter for this post in my blog.

The influence on physics of aesthetic ideas is very old, perhaps as old as physics. One of its oldest precursors is Pythagoras, who proposed the concept of the harmony of the celestial spheres, according to which the distances between the planets would reproduce harmonious musical intervals.