Pierre Maurice Duhem (9 June 1861 – 14 September 1916) was a physicist, epistemologist, and historian of science. He maintained that the history of science and ideas is important for a correct scientific epistemology. He contributed to a reexamination of the role Christian theology played in the formation of the Western scientific spirit, chiefly through his monumental work “Le système du monde. Histoire des doctrines cosmologiques de Platon à Copernic” (10 volumes), whose publication was completed after his death. Duhem criticized the claims of the mechanist and materialist philosophies, stating that they operated on illegitimate extrapolations from results obtained in physics. He considered metaphysics the field of first principles and of the notions upon which physics is based, while leaving physics the full freedom to formulate its own models and delineations. His principal reflections on the relationships between physics and metaphysics are found in his work “La théorie physique, son objet et sa structure” (1906).
The Templeton Foundation announced today that Marcelo Gleiser is the 2019 Templeton Prize Laureate. Marcelo Gleiser is theoretical physicist, cosmologist, and a leading proponent of the view that science, philosophy, and spirituality are complementary expressions of our need as humans to embrace mystery and the unknown. He is originally from Brazil and is now Professor of Natural Philosophy and a professor of physics and astronomy at Dartmouth College in Hanover, New Hampshire. He has earned international acclaim through his books, essays, blogs, TV documentaries, and conferences that present science as a spiritual quest to understand the origins of the universe and of life on Earth. He considers himself a non-believer and an agnostic, emphasizing that agnosticism seems for the non-believer the best position, since the atheistic position is not consistent with the state of scientific knowledge we have. He thus is a prominent voice among scientists, past and present, who reject the notion that science alone can lead to ultimate truths about the nature of reality.Continue reading
On 20 February 1778, Laura Maria Caterina Bassi died at the age of 66. She was the first woman in the world to earn a university chair in a scientific field of studies. She received a doctoral degree from the University of Bologna in May 1732, only the third academic qualification ever bestowed on a woman by a European university, and the first woman to earn a professorship in physics at a university in Europe. She was the first woman to be offered an official teaching position at a university in Europe.
On 17 April 1732, Bassi defended her theses for the degree of doctor of philosophy. Several of her theses showed the influence of Isaac Newton’s works on optics and light. Two months later, she defended another set of theses about the properties of water, which led to her being awarded an honorary post at the university as a professor in physics.
In 1738, she married Giuseppe Veratti, a fellow academic with whom she had twelve children. After this, she was able to lecture from home on a regular basis and successfully petitioned the University for more responsibility and a higher salary to allow her to purchase her own equipment. She made physics into a lifelong career and broke a huge amount of ground for women in academic circles.
Graphic: Portrait of Italian mathematician and physicist Laura Bassi (1711-1778) by Carlo Vandi (18th century)
On 1 September 1648, Marin Mersenne (1588-1648) died in Paris. A French philosopher, physicist, and ordained priest, he acted as a liason between a number of the scientists and thinkers of his time, such as Fermat, Gassendi, and Pascal. He defended Descartes and Galileo against criticism from theologians and fought against pseudo-sciences such as astrology and alchemy. Mersenne is also remembered today thanks to his association with the Mersenne primes. The Mersenne twister, named for him, is frequently used in computer engineering, and in related fields such as cryptography. However, Mersenne was not primarily a mathematician; he wrote about music theory and other subjects. He edited works of Euclid, Apollonius, Archimedes, and other Greek mathematicians. But perhaps his most important contribution to the advance of learning was his extensive correspondence (in Latin) with mathematicians and other scientists in many countries. He also performed extensive experiments to determine the acceleration of falling objects by comparing them with the swing of pendulums, reported in his Cogitata Physico-Mathematica in 1644. He was the first to measure the length of the seconds pendulum, that is a pendulum whose swing takes one second, and the first to observe that a pendulum’s swings are not isochronous as Galileo thought, but that large swings take longer than small swings.
On 8 July 1695, Christiaan Huygens (1629–1695) passed away at The Hague. A mathematician, physicist, and astronomer, he was also interested in philosophy and humanistic studies. In his mechanistic conception of light and gravitation he was inspired by Descartes’ thought. He knew Blaise Pascal with whom he corresponded about mathematical problems. He grappled with problems in plane geometry, optics, wave theory, and collision. He designed microscopes and telescopes and discovered Saturn’s rings, which Galilean observations had not yet been able to decipher.
Among others, Dutch physicist Christian Huygens introduced the concept of Entrainment in 1666 after he noticed that the pendulums of two clocks mounted on a common board had become synchronized, and his subsequent experiments duplicated this phenomenon. He termed this effect as “odd sympathy”. The two pendulum clocks synchronized with their pendulums swinging 180° out of phase (in opposite directions), but the in phase states were also observed. It is theorized that entrainment occurs because small amounts of energy are transferred between the two systems when they are out of phase in such a way as to produce negative feedback. As they assume a more stable phase relationship, the energy transfers are gradually reduced to zero. Within other topics of physics, Huygens’ theory of entrainment is related to the resonant coupling of harmonic oscillators, which also gives rise to sympathetic vibrations.
Entrainment has been used as a term to describe the process of mode locking of coupled driven oscillators, which is the process whereby two interacting oscillating systems, which have independent and different periods, assume a common period, which might be not only synchrony, but also other phase relationships. In general, the system with the greater frequency slows down, and the other speeds up. A 2002 study of Huygens’ observations demonstrated that his observation of an antiphase stable oscillation was somewhat fortuitous, noting that there are other possible stable solutions, including a stationary state where a clock stops running. Mode locking between driven oscillators can be demonstrated in labs by using mechanical metronomes on a common, easily movable surface. It is believed that many biological systems utilize such mode locking, including in the proper operation of pacemakers and other biological rate processes.
Sources: inters.org; wikipedia.
Painting: Christiaan Huygens by Bernard Vaillant (1632 – 1698)
On 12 March 1942, Sir William Henry Bragg (1862–1942) passed away in London, UK.
With his son, William Lawrence Bragg (1890–1971), William Henry Bragg was co-awarded the 1915 Nobel Prize in Physics, a unique Nobel honor shared by a father and son: “for their services in the analysis of crystal structure by means of X-rays.” The mineral Braggite is named after him and his son.
Quote from Sir William Henry Bragg (1862–1942):
“From religion comes a man’s purpose; from science, his power to achieve it. Sometimes people ask if religion and science are not opposed to one another. They are: in the sense that the thumb and fingers of my hands are opposed to one another. It is an opposition by means of which anything can be grasped.”
Werner K. Heisenberg (05 December 1901 – 01 February 1976) was a German theoretical physicist who devised a method to formulate quantum mechanics in terms of matrices, for which he was awarded the 1932 Nobel Prize for Physics. Heisenberg is widely considered as one of the most influential figures in nuclear physics, particle physics and quantum field theory.
An author of philosophical works, his “uncertainty principle” contributed to overcoming deterministic mechanics, while at the same instigating a lively epistemological debate about the nature of the real.
“The existing scientific concepts cover always only a very limited part of reality, and the other part that has not yet been understood is infinite. Whenever we proceed from the known into the unknown we may hope to understand, but we may have to learn at the same time a new meaning of the word ‘understanding’.”
Werner Heisenberg (1901-1976)
German theoretical physicist & one of the key pioneers of Quantum Mechanics