Category Archives: Physique
Mécanique des solides déformables
Alien Worlds: The Science of Exoplanet Discovery and Characterization
Alien Worlds will explore the techniques that are used to discover and characterize the thousands of planets (called exoplanets) known outside of our solar system.
About this Course
Have you ever wondered about planets in other solar systems? Have you ever thought about the possibility of life elsewhere in the Universe? For the first time in human history, we know that planets around other stars not only exist, but are common!
Alien Worlds focuses on the search and characterization of planets orbiting other stars (called extrasolar planets or “exoplanets”). Over the course of nine modules, we will learn some of the techniques used to discover the thousands of known exoplanets and will discuss how we can use basic scientific tools to characterize the sizes, masses, compositions, and atmospheres of exoplanets. We will also learn about the diversity of stars in the Galaxy to understand how stellar properties affect exoplanet detection techniques and influence planetary formation and habitability.
In addition to the exploration of exoplanets, students in Alien Worlds will gain a basic understanding of light, gravity and motion, and be introduced to some of the most extreme life on planet Earth. We will hear from experts at the forefront of exoplanet science and interact with other participants and instructors through social media and online tools. Students will leave Alien Worlds with a better understanding of their place in the Universe and the skills to comprehend the wealth of new discoveries surrounding the countless worlds around distant stars.
Physique de l’intérieur de la terre.
Stockage et conversion de l’énergie : synthèse et perspectives
Comment les choses fonctionnent.
Designed for non-science students, this course is a practical introduction to physics and science in everyday life. It considers objects from the world around us, identifying and exploring the scientific concepts upon which they’re based. Because it starts with objects and looks within them for science, it is the reverse of a traditional physics class. Instead of the usual principle-driven physics class, How Things Work is case-study physics.
In this pilot semester of How Things Work, we will explore the basic laws of motion in the context of six familiar objects or activities: (1) Skating, (2) Falling Balls, (3) Ramps, (4) Seesaws, (5) Wheels, and (6) Bumper Cars. Despite their simplicity, these topics will bring us in contact with some of the most important concepts in physics, including inertia, energy, and momentum.
This course is self-paced. You can begin anytime and proceed at whatever speed you like. Although it typically takes about six weeks, you can finish it in three months or three days. With students ranging in age from 7 to 80+, there is little reason to follow a conventional academic schedule. This course should fit your lifestyle, not the other way around.
Subtitles are now available in more than 13 languages, with many translations prepared by volunteers from the course. Those translations are complete in Chinese and French, and nearly complete in German, Hebrew, Japanese, and Spanish. Other languages include: Arabic, Greek, Hindi, Italian, Korean, Portuguese, Russian, and Urdu.
La formation et l’évolution des galaxies
La superfluidité
“Peut-on voir au moins une propriété quantique de la matière à l’oeil nu ? Oui, il suffit de regarder de l’hélium liquide à suffisamment basse température. Je montrerai un liquide qui cesse de bouillir, jaillit en fontaine lorsqu’on le chauffe, s’écoule sans viscosité hors des récipients où l’on tente de l’enfermer (d’où son nom de ” superfluide “)… J’expliquerai ensuite comment ces propriétés surprenantes ont été associées au comportement collectif quantique des atomes, un phénomène connu sous le nom de ” Condensation de Bose-Einstein “. Les différents états de la matière correspondent à différents degrés d’ordre ou de désordre. Lorsqu’un liquide cristallise, par exemple, c’est la position des atomes dans l’espace qui s’ordonne. Lorsqu’un fluide devient superfluide c’est leurs mouvements qui deviennent collectifs. De même qu’un superfluide coule sans viscosité, un supraconducteur conduit l’électricité sans résistance. La superfluidité est semblable à la supraconductivité des métaux. Connue depuis 1937 dans l’hélium, la superfluidité a été découverte en 1999 dans différentes vapeurs alcalines. Nous verrons que la rotation d’un superfluide est très particulière, parce que quantifiée. Dans l’hélium comme dans le rubidium, nous montrerons des images de tourbillons quantiques où la vitesse du fluide est reliée à la constante de Planck. Pour conclure, nous décrirons comment la superfluidité peut servir à mesurer la rotation de la terre, et pourquoi l’on pense que l’intérieur des étoiles à neutrons est superfluide.”