Tag archives: quantum physics
Quantum mechanics in a cup of coffee, hamming it up to the space station, the laws of political physics and more
By Hamish Johnston and Michael Banks
Physicists tend to drink lots of coffee so I wasn’t the least bit surprised to see the above video of Philip Moriarty explaining quantum mechanics using a vibrating cup of coffee. Moriarty, who is at the University of Nottingham, uses the coffee to explain the physics underlying his favourite image in physics. You will have to watch the video to find out which image that is, and there is more about the physics discussed in the video on Moriarty’s blog Symptoms of the Universe.
By Hamish Johnston and Michael Banks
You may remember back in 2013 when researchers at the National Institute of Standards and Technology (NIST) in the US entangled the motion of a tiny mechanical drum with a microwave field for the first time ever. Not content with that feat, NIST physicist Ray Simmonds, who was involved in the work, has now made a dance about it (but no song, yet). Teaming up with choreographer Sam Mitchell, the duo has created a modern dance piece entitled Dunamis Novem (“The chance happening of nine things”). Featuring four dancers, their movements are based on nine quantized energy levels of a harmonic oscillator – like the microscopic drum in the NIST work. For each level, Mitchell created corresponding dance actions, while Simmonds created a random-number generator – to add some “quantum randomness” – for the sequence of levels that the dancers perform at. If the dancers happen to touch each other, their actions become synchronized, which can then only be broken by a beam of light – demonstrating that a measurement collapses the entanglement.
NIST has published a Q&A with Mitchell and Simmonds with links to videos of the dance and the animations of the corresponding energy levels of the harmonic oscillator. A video of the first half of Dunamis Novem is shown above and a video of the entire dance is also available.
By Robert P Crease in Singapore
It’s not often that you come across a museum exhibit based on a Physics World article. But I did on Saturday at the Mind Museum – an extraordinarily beautiful and original science museum in Taguig, on the outskirts of Manila in the Philippines.
Not only that, the exhibit is right at the entrance. You may recall that I once asked Physics World readers for their thoughts on the 10 most beautiful experiments and wrote up the results in an article in September 2002. The project turned into a book, The Prism and the Pendulum: The Ten Most Beautiful Experiments in Science, which came out the following year and which Physics World reviewed.
Maria Isabel Garcia, who was planning exhibits for the then-future Mind Museum, saw the article and book, and created an exhibit based on it, consisting of videos and explanations of each of the 10 experiments, along with a sculpture designed by the Philippine artist Daniel de la Cruz.
This article first appeared in the “Lateral Thoughts” section of the July 2014 issue of Physics World
By Felix Flicker
If someone puts you in an armlock, what should you do? If you happen to be a martial artist well-practised in the art of joint manipulation, or chin na, you will know the answer already: there is one simple move that will allow you to turn the tables on your aggressor, leaving them on the wrong end of a throw. However, if your skill set tends more toward manipulating mathematical symbols, there is still hope, for the answer is also closely tied to theoretical physics.
By Matin Durrani
This year marks the 50th anniversary of the publication of a now-famous paper in the journal Physics by the Northern Irish physicist John Bell, in which he proved that making a measurement on one particle could instantaneously affect another particle – even if it’s a long way off.
As our regular columnist Robert P Crease writes in the November issue of Physics World magazine, that kind of instantaneous effect, which proved the concept of entanglement, was not something that Bell was originally keen on. In fact, Bell had actually set out to prove the opposite – that it was possible, using “hidden variables”, to have a theory of physics that could keep things nice and “local”, and so avoid what Einstein had dubbed “spooky action at a distance”.
But Bell reversed his thinking. “I made a phase transition in my mind,” he told Crease shortly before his death in 1990 aged 62.
Yesterday (4 November) marked the 50th anniversary of the day that Bell’s paper arrived at the journal’s offices and today (5 November) sees the opening of an exhibtion at the Naughton Gallery on the campus of Queen’s University Belfast, from which Bell graduated with a first-class degree in mathematical physics in 1949.
Entitled “Action at a distance”, the exhibition runs until 30 November and promises to “explore Bell’s life and the artistic response to his legacy by artists from across the world”. There is also an accompanying series of lectures from Andrew Whitaker, Maire O’Neill, Mauro Paternostro, Artur Ekert and Anton Zeilinger.
By Tushna Commissariat
It’s been nearly two weeks since I spent three intense and interesting days in Sweden bundled into a classroom with other journalists and scientists to polish up our knowledge of all things quantum. Since attending the NORDITA science-writing workshop, I have spent a lot of time thinking about one of the main themes of the meeting: “What is the best way to communicate quantum physics to the public?”
By Tushna Commissariat in Stockholm, Sweden
Google the word “quantum” and take a look at what comes up.
In addition to the obvious news articles about the latest developments in the field and the Wikipedia entries on quantum mechanics, you’ll undoubtedly come across a heap of other, seemingly random, stories.
I found, for example, a David Bowie song being compared to a quantum wavefunction (by none other than British science popularizer Brian Cox), as well as a new cruise ship being named Quantum of the Seas. Then there’s the usual jumble of pseudo-scientific “wellness” therapies that misguidedly adopt the word in a strange attempt to give their treatments some sort of credibility.
So while it seems that everyone is talking about quantum something or other, how much do we really understand this notoriously difficult subject? More to the point, how much do science journalists, like me, really know about the subject? I write stories about quantum mechanics from time to time for Physics World and the subject can, I assure you, be fiendish and quite mind-bending.
By Hamish Johnston
Last year we reported on a fascinating experiment that simulated the quantum Hall effect using light. Mohammad Hafezi and colleagues at the Joint Quantum Institute (JQI) of the University of Maryland created a lattice of ring-shaped silicon waveguides that are placed just nanometres apart (see image above). This allows light in one ring to “tunnel” into a neighbouring ring and make its way across the matrix, hopping from ring to ring.
By Tushna Commissariat at the APS March Meeting in Denver
It has been another exceedingly busy day the APS March Meeting – there were sessions on the SQUID’s many applications, robotic clams, global health physics and the spread of epidemics, and even some toys based on physics principles. Here’s another quick round-up of the fascinating talks.
On SQUID row
It’s the 50th birthday of the superconducting quantum interference device or SQUID – a very sensitive magnetometer that accurately measures extremely subtle magnetic fields – this year, and there were sessions this morning to discuss its impact to date as well as possible future applications. Kent Irwin from Stanford University discussed how superconducting photon detectors that are used in a host of astronomical and cosmological observations are being amplified using SQUIDs. Such SQUID-boosted sensors are being used to make more accurate measurements of the cosmic microwave background (CMB) – to look at its power as well as certain polarizations modes it exhibits. As certain experiments look for signs of gravitational waves in in the CMB polarization, this could be particularly helpful.
By Tushna Commissariat
If you like piña coladas and quantum mechanics, then we hope you are currently on the two-week “Bright Horizons 19” Southeast Asia cruise, as on board is physicist and writer Sean Carroll. He will be giving multiple lectures over the next 15 days on everything from the Higgs boson to dark matter and other fundamentals of quantum mechanics. Also floating along with Carroll are other lecturers who will cover topics from natural history to genetics to military strategy. If, like us, you are stuck at home, you can take a look at Carroll’s slides on his blog, maybe have a cocktail while you are at it.