A previous piece (“Patterns in Physics”) discussed alternative “representations” in physics as akin to languages, an underlying quantum reality described in either a position or a momentum representation. Both are equally capable of a complete description, the underlying reality itself residing in a complex space with the very concepts of position/momentum or wave/particle only relevant in a “classical limit”. The history of physics has progressively separated such incidentals of our description from what is essential to the physics itself.
Many dominoes may be stacked in a row separated by a fixed distance, in all sorts of interesting formations. A slight push to the first domino in the row results in the falling of the whole stack. This is the domino effect, a term also used in figuratively in a political context. You can use this amusing phenomenon to carry out a little project in physics.
Although we rarely stop to think about the origin of the elements of our bodies, we are directly connected to the greater universe. In fact, we are literally made of stardust that was liberated from the interiors of dying stars in gigantic explosions, and then collected to form our Earth as the solar system took shape some 4.5 billion years ago.
Many of you have likely seen the beautiful grand spiral galaxies captured by the likes of the Hubble space telescope. Images such as those below of the Pinwheel and Whirlpool galaxies display long striking spiral arms that wind into their centres.
Rubber bands are unusual objects, and behave in a manner which is counterintuitive. Their properties are reflected in characteristic mechanical, thermal and acoustic phenomena. Such behavior is sufficiently unusual to warrant quantitative investigation in an experimental project. A well-known phenomenon is the following. When you stretch a rubber band suddenly and immediately touch your lips with it, it feels warm, the rubber band gives off heat.
You may have seen the drinking bird toy in action. It dips its beak into a full glass of water in front of it, after which it swings to and fro for a while, returns to drink some more, and so on, seemingly forever. You can buy one on the internet for a few dollars, and perform with it a fascinating physics project. But how does it work?
If you are a student or an instructor, whether in a high school or at university, you may want to depart from the routine of lectures, tutorials, and short lab sessions. An extended experimental investigation of some physical phenomenon will provide an exciting channel for that wish. The payoff for the student is a taste of how physics research is done. This holds also for the instructor guiding a project if the guide’s time is completely taken up with teaching. For researchers it seems natural to initiate interested students into research early on in their studies.
The aim of physics is to understand the world we live in. Given its myriad of objects and phenomena, understanding means to see connections and relations between what may seem unrelated and very different. Thus, a falling apple and the Moon in its orbit around the Earth. In this way, many things “fall into place” in terms of a few basic ideas, principles (laws of physics) and patterns.
When I wrote Materials: A Very Short Introduction (published later this month) I made a list of all the Nobel Prizes that had been awarded for work on materials. There are lots. The first was the 1905 Chemistry prize to Alfred von Baeyer for dyestuffs (think indigo and denim). Now we can add another, as the 2014 Physics prize has been awarded to the three Japanese scientists who discovered how to make blue light-emitting diodes.
World Space Week has prompted myself and colleagues at the Open University to discuss the question: ‘Is there life beyond Earth?’ The bottom line is that we are now certain that there are many places in our Solar System and around other stars where simple microbial life could exist, of kinds that we know from various settings, both mundane and exotic, on Earth. What we don’t know is whether any life DOES exist in any of those places.
Today, 60 years ago, the visionary convention establishing the European Organization for Nuclear Research — better known with its French acronym, CERN — entered into force, marking the beginning of an extraordinary scientific adventure that has profoundly changed science, technology, and society, and that is still far from over.
2014 marks not just the centenary of the start of World War I, and the 75th anniversary of World War II, but on 29 September it is 60 years since the establishment of CERN, the European Centre for Nuclear Research or, in its modern form, Particle Physics.
René Descartes wrote his third book, Principles of Philosophy, as something of a rival to scholastic textbooks. He prided himself in “that those who have not yet learned the philosophy of the schools will learn it more easily from this book than from their teachers, because by the same means they will learn to scorn it, and even the most mediocre teachers will be capable of teaching my philosophy by means of this book alone” (Descartes to Marin Mersenne, December 1640).
The discovery of the periodic system of the elements and the associated periodic table is generally attributed to the great Russian chemist Dmitri Mendeleev. Many authors have indulged in the game of debating just how much credit should be attributed to Mendeleev and how much to the other discoverers of this unifying theme of modern chemistry.
Dmitri Mendeleev believed he was a great scientist and indeed he was. He was not actually recognized as such until his periodic table achieved worldwide diffusion and began to appear in textbooks of general chemistry and in other major publications.
Time is running short. When the IPCC published its first scientific report in 1990 on the possibility of human-caused global warming, the atmospheric concentration of carbon dioxide (CO2) was 354 ppm. It is now 397 ppm and rising. In spite of Kyoto, Copenhagen, Cancun, Durban, and Doha, atmospheric CO2 continues its inexorable upward path.