Tuesday, September 4, 2012

Dreaming in Geneva - FQXi essay

The theme for this year's FQXi contest topic is "Questioning the Foundations: Which of Our Basic Physical Assumptions are Wrong?". I had some difficulty to start with this topic (I didn't seem to be the only one, see Ajit Jadhav's blog here and there). I had a lot of things to say about what has gone wrong with physics, which assumptions had to be reconsidered. So, since the opening of the contest, I regularly put some ideas in a draft, being confident that I would be able to arrange them into a coherent thesis for the essay. However by the 20th of August (ten days before closing), I still didn't know how I could write them together into an essay without being suspected of "trotting out my pet theory" (see warning in the Evaluation Criteria).

My "pet theory" is simple: the fundamental entity in physics is "THE quantum particle" which you can represent as an arrow (a vector, a ket). From the mechanical interactions between such rod-like particles, you may deduce all of physics, provided that you assume some complementary parameters (such as the velocity at which two particles fly one from another = c, the length of the rod = Bohr diameter of hydrogen). No mass, no force, no charge, etc. Just paths of rotating arrows that interact with each other through contact (collision). This is the way I reason about photons, electrons, quarks, fields, waves, etc. But I can't reasonably write it that way in an essay. I would need to recall a lot of history of science. So I chose to bring up some ideas that have emerged in history of science that we could reconsider, not necessarily in the same way, but gaining insight with hindsight.

Also I prefer to avoid abstract mathematics when talking physics. Mathematics is just a language, very convenient though, but really just a language that can hinder us in our intuitive understanding. Instead of math, scientists could as well use words, fantasy, dreams, pictures, poems maybe. It is an art and sometimes it is necessary to change the expression of this art. I hope you'll enjoy my dreaming in Geneva.

Thursday, August 23, 2012

Auguste Bravais - 201st birthday anniversary

On August 23, 1811, during a relatively calm period of Napoleon's reign, Aurélie-Adelaïde Thomé, spouse of physician François-Victor Bravais, gave birth to Auguste in Annonay. Annonay is located just south east of the Pilat massif, in the French mild climate department of the Ardèche.

Some 30 years earlier, the people of Annonay witnessed the first public hot-air balloon flights, as it was the hometown of the Montgolfier brothers. Buth both brothers died before Auguste was given the privilege to nest in Annonay. As last one, Joseph-Michel died almost one year earlier. Auguste surely benefited from the scientific entrepreneurial spirit of that town.

Stanislas College caption
He was sent to Paris for his studies, first at the college Stanislas. And consequently was admitted to Polytechnique.

Auguste Bravais is best known for pointing out that there are in total 14 types of crystallographic lattices. His ordering and denomination of lattices is still in use today.

In his young years, his main interest was in meteorological observations. At age 10, he climbed alone the Pilat mountain hoping to better understand cloud formation. Later in his life, together with two other scientists, he participated in the first scientific mission at the top of the Mont-Blanc, as well as in numerous observations on the Faulhorn with his brother Louis.

With Louis, he also shared a passion for botany, which was given to them by their father. Together, they investigated the arrangement of leaves on the stem of plants, which shows Fibonacci series in their spiraling. They came to the conclusion, that the leaves were never really growing vertically of each other. There was a prevalent tendency that two successive leaves were following each other on a spiral at 137.5 degrees (or, which is the same, at 222.5 degrees counter-wise). This result they published in 1835.

In 1868, Wilhelm Hofmeister gave an explanation for that angle, now known as Hofmeister's rule: as the plant grows, each new leave originates at the least crowded spot. A very natural law...

Sadly, for the last ten yours of his life, he lost his intellectual capacities, being aware that he could not fulfill the redaction of all his scientific work. He was said to start work at 4 o'clock in the morning with a lot of caffeine  The lack of sleep surely didn't arrange things. He died March 30, 1863 near Versailles.

Wednesday, August 15, 2012

Louis de Broglie - 120th birthday anniversary

Exactly 120 years ago, on August 15th, 1892, Louis de Broglie was born in Dieppe, a little town on the coast of Normandy. De Broglie is one of my favorite physicists because he has tried to conciliate quantum theory with intuition. He entered the physics stage after the first World War, where he had served as radiographer on the Eiffel tower. That stimulated his interest in electromagnetic radiation questions. At that time, it became clear that electromagnetic radiation could be explained as well by wave mechanics (constructive and destructive interference as evidenced by Thomas Young in 1803), as by a collection of particles (photoelectric effect explained by Albert Einstein in 1905). Louis de Broglie made an important following step: if light had dual wave-particle behavior, matter also should have that duality.

De Broglie tried to interpret this duality as phase matching between a particle embedded in a wave, the pilot wave. There should be phase matching between both: "les photons incidents possèdent une fréquence d’oscillation interne égale à celle de l’onde (my translation: the incident photons have an internal oscillation frequency equal to that of the wave)". He saw photons, as well as electrons, as little clock-watches embedded in their wave. I am sure this intuition will lead to new physics in the future, because this aspect of duality has hardly been investigated, see Couder's bouncing droplets in pilot wave. Personally I am working with this pilot wave idea in order to explain some properties of quantum dots.

As Louis de Broglie lived his last years in a little town, Louveciennes, that is close to where I live, I had a walk there today. Maybe I could find some place related to him. Unfortunately, I didn't find the exact location of his residence  (please drop a comment if you know). But surely the scenery of the pictures below near to the royal residence of the Manoir du Coeur Volant must have been very familiar to him.
Manoir du Coeur Volant

Abreuvoir of Marly-le-Roi

Royal Domain of Marly-le-Roi

Commemoration plaque of the Manoir du Coeur-Volant

Thursday, March 15, 2012

Electronic vibrations in ski poles

Two weeks ago, I was skiing in the Vosges mountains. The ski resort Lac Blanc is crossed by 400 kV high tension transmission lines which run over the ski trails at a height about 8 - 10 m. While waiting under them, I had the surprise to "feel" electronic vibrations in the ski pole with the tip of my fingers, as if bunches of electrons were running back and forth on the surface of the pole. Experimenting a bit with them, I noticed that the ski pole had to be planted in the ground (or the snow in this case) to set up these vibrations. For ski poles where the tip was isolated with a plastic material, there were no such vibrations. Also, this worked whatever the orientation of the pole, parallel or perpendicular to the transmission lines, which I found quite surprising. Whatever, I tried not to dwell too long under those lines, not sure to which extent these transmission lines affected my neuronal electrons ;-)


Saturday, February 4, 2012

Spinning dancers around poles

Some ideas for a spinning dancers choreography, representing spinning electrons with spin up and down, inspired by Pauli exclusion principle: http://commonsensequantum.blogspot.com/2010/10/explaining-electron-spin-and-pauli.html

All electrons spinning at same speed:

With an excited electron, spinning twice the speed of other electrons. At that speed, it doesn't disturb the dance:

To be continued with perturbing dancers representing laser light.