Tag archives: history of physics
By Tushna Commissariat
The results of a successful scientific experiment can make scientists very happy. Indeed, in the clip above, taken from the BBC TV series Human Universe, one scientist exclaims “holy mackarel!” when he sees the outcome he was hoping for. In the video, everybody’s favourite physicist Brian Cox carries out an experiment similar to Galileo’s Leaning Tower of Pisa experiment, where he tested that no matter the mass of objects, they fall at the same rate under gravity. In the video above, Cox drops a bunch of feathers and a bowling ball in the world’s biggest vacuum chamber – the Space Simulation Vacuum Chamber at NASA’s Space Power Facility in Ohio, US. In the slow-motion video, you can see with exquisite clarity just how accurate Galileo’s prediction was, as the feathers and ball land at precisely the same time. We came across this video on the Dot Physics blog on the Wired Science network, written by physicist Rhett Allain, where he has worked out some of the maths and pointed out some of the nuances of the above experiment, so make sure you take a look.
By James Dacey in Córdoba, Argentina
What’s the best way to teach tricky physics concepts to students? Naturally, this was one of the questions underpinning many of the talks here at the International Conference of Physics Education (IPCE) in Córdoba. According to a couple of educationalists in Latin America at least, it seems that one approach is to enlist the help of some of the great scientists and philosophers of the past.
Patricia del V. Repossi, a lecturer at the Pontificia Universidad Católica Argentina in Buenos Aires, spoke about how she uses the history of science as a framework for teaching optics. Repossi explained how she had come to realize that some of the students taking her conventional optics course believed that photons are made of the same stuff as “tennis balls”. So, she and her colleagues set about transforming the way they teach the topic – by combining a physics class with a history lesson.
By Hamish Johnston
“How we created spooky experimental music in a superconductor lab”: what physicist could resist clicking on this story, which appeared on the Guardian website earlier this week? Written by the physicist-turned-computational-biologist Andrew Steele, the article describes how Steele and a few pals converted a magnetic sensor into a musical instrument. Like the theremin, which is played by waving your hands around an antenna, this new instrument responds to the player’s motion. But because the sensor was optimized for studying superconductors rather than creating freaky mood music, Steele explains the “instrument covered three octaves in less than a centimetre of hand movement”. He suggests that playing the instrument should probably be left to a talented gerbil rather than talented superconductor researchers. You can listen to Steele’s attempt at making music on SoundCloud.
By Margaret Harris
Last Sunday I went up to Cheltenham for the final day of the town’s annual Science Festival. My plan was to meet the University of Maryland theorist Jim Gates before lunch and then stay to hear his lecture on science and policy.
I was already somewhat familiar with Gates’ research thanks to a feature he wrote for Physics World in June 2010. I could also have made an educated guess about his activities as a member of the President’s Council of Advisers on Science and Technology (PCAST). However, I knew very little about his personal history before his evening lecture, when he was interviewed by the physicist and science presenter Jim Al-Khalili.
Gates was born in 1950 and grew up during a period when African-Americans faced severe institutionalized discrimination across the US. However, being from a military family helped insulate him from some of the worst effects, and he told the audience that he didn’t feel the full impact until his family moved to Florida after he turned 11. For the first time, he attended a racially segregated school, and there, he said, he had “the very curious experience of having to learn how to be black”.
By James Dacey, reporting from Sheffield
“I wanted to make a film about an old space cowboy” is how British director Mark Craig introduced his new film on Sunday afternoon here at Sheffield Doc/Fest. The Last Man on the Moon takes a fresh look at the the Apollo era through the story of Eugene Cernan, who was the last person to set foot on the lunar surface when he did so in 1972 as commander of Apollo 17.
The documentary interleaves a profile of “Gene” Cernan with NASA archive footage and special effects, focusing on the personal stories of the astronauts and their families. To give you a flavour, the film opens in the present day with close-ups of Cernan’s facial reactions at a rodeo event as he admires the spectacle and the bravery of the men being thrown around on the back of bulls. Later in the film, Cernan recounts his experiences of being rotated rapidly in space during the Gemini 9A and Apollo 10 missions.
Immediately after the showing, Cernan and Craig stayed for a Q&A session and the audience gave an extended standing ovation as the 80-year-old astronaut walked to the front of the auditorium. I was fortunate to catch up with the pair this morning to get some insights into the inspiration for the film and how it was adapted from the book Cernan co-authored in 1999.
By Hamish Johnston
Can you name 10 blunders that have held back the progress of modern astronomy? Avi Loeb of Harvard University can, and he lists them in an essay entitled “On the benefits of promoting diversity of ideas”, which is posted on the arXiv preprint server.
Loeb argues that a common flaw of astronomers is to believe that they know the truth even when data are scarce. This, he argues, “occasionally leads to major blunders by which the scientific community makes the wrong strategic decision in its research plans, causing unnecessary delays in finding the truth”.
The first example he gives is the 1909 pronouncement by Edward Pickering, director of the Harvard College Observatory, that telescopes had reached their optimal size and that there was no point trying to make them any bigger.
By Matin Durrani
Things seem to have quietened down a bit following last month’s announcement by astronomers in the BICEP2 collaboration that they had obtained the first evidence of cosmic inflation – the period of rapid expansion in the first fraction of a second after the Big Bang. As you’ll know if you’ve been keeping up, the evidence was obtained by searching for certain “B-mode” polarizations in the cosmic microwave background, which are related to primordial gravitational waves that are thought to have abounded in the early universe. These polarizations differ from “E-mode” polarization, which describes how the magnitude of polarization varies across the CMB.
But never mind your fancy B-modes and E-modes, how well do you understand the concept of polarization in the first place? Intriguingly, in the late 1840s Sir Charles Wheatstone, who was then professor of experimental philosophy at the University of London, decided to create a mechanical device to explain the principles of the concept – several decades before James Clerk Maxwell’s theory of the electromagnetic nature of light.
The video above shows a rare surviving example of one of these “Wheatstone Wave Machines”, which has been restored to working order by Robert Whitworth and colleagues at the University of Birmingham in the UK as part of their collection of historic physics instruments. Wheatstone designed the machine to visualize the wave nature of light and offer what Whitworth calls “a vivid insight into the theoretical concepts of wave motion”. At the time, there were other devices that showed the behaviour of travelling plane waves, but Wheatstone’s was different in that it was the first to demonstrate circularly polarized light.
By Margaret Harris
As part of Physics World’s 25th anniversary celebrations, I’ve been reading through the archive of “Lateral Thoughts”, the magazine’s column of humorous or otherwise off-beat essays about physics. My goal is to get a better feel for the topics that have amused and preoccupied Physics World readers over the past quarter-century, and to understand how the community has changed.
While most Lateral Thoughts have focused on the world of physics, the archive shows that every now and then, the wider world intrudes. The results can be fascinating, sobering and sometimes even disturbing. Consider the essay “Soft zlotys for western hardware”, in which the metallurgist Jack Harris describes taking a research trip behind the Iron Curtain to Poland. “In science, as in other areas, I was struck by how little real contact there was with Russia,” Harris wrote. His Lateral Thought was published in July 1989. Two months later, Poland defied its puppet-masters in Moscow by electing its first non-communist government since the Second World War.
By Margaret Harris
As Physics World’s reviews editor, I come across a lot of books that interest me intellectually. But with Kate Brown’s book Plutopia – the subject of this month’s Physics World podcast – my interest is personal, too.
Brown’s book tells the story of two cities, Richland in the US and Ozersk in the former Soviet Union, that were built to house workers at the nearby Hanford and Maiak plutonium plants. Brown calls these cities “plutopias” because high wages and subsidies meant that residents enjoyed a better standard of living than their neighbours outside the secure zones. Such benefits, in turn, fostered an atmosphere of loyalty and solidarity that helped keep the plants’ horrendous environmental records under wraps.
This sounded familiar to me because my childhood had a decidedly “plutopian” flavour. Although I didn’t grow up in an “atomic city” like Richland or Ozersk, my father worked for a defence contractor for 39 years, and his plant’s generous vacation allowance meant that we took longer holidays than most American families. We had good health insurance, too, which may have saved my life as a teenager. But after reading Plutopia and speaking to Brown for the podcast, I found myself wondering whether such benefits were a fair trade for working, as my father and thousands of others did, in a mostly windowless building that was surrounded by razor wire and contaminated with beryllium dust.
By Tushna Commissariat at the APS March Meeting in Denver
The city of Denver, Colorado has been invaded…or so I am sure the locals will feel over the next few days, as more than 9000 physicists from all over the world have arrived to take part in the APS March Meeting. I have been here in the “Mile-high city” of Denver – so nicknamed thanks to its official elevation that is exactly one mile or 5280 feet above sea level – since Sunday morning, and physics is the talk of the town as everyone descends upon the Colorado Convention Center (pictured above).
As always, there is a wide variety of interesting talks, sessions and press conferences over the next few days and I would have to clone myself multiple times to get around to all of them. Talking about cloning, though – I have just been to my first session, where Stanford researcher Patrick Hayden was taking about quantum information and asking whether or not it could be cloned in space–time. I will be speaking with Hayden later in the day, so watch this space if you would like to know more.