It’s hard to believe that the kilogram is still based on a lump of metal in a vault in Paris. But that all looks set to change this month at a meeting of scientists and policy-makers in Paris, where it should be redefined in terms of the Planck constant.
The imminent redefinition of the kilogram – and other SI units that are still based on physical phenomena artefacts – is the cover story of the November 2018 issue of Physics World magazine, which is now out in our digital apps for iOS, Android and Web browsers.. We don’t want to be rude, but the cover shows an h, the symbol for the Planck constant, kicking the kilogram into touch.
The story’s been written by science writer Benjamin Skuse, who explains why the International Prototype Kilogram is set to get the boot this month as part of a wider overhaul of SI units. Elsewhere in the special issue, Helen Margolis from the UK’s National Physical Laboratory tells you all you need to know about optical clocks, while Stephen Ornes guides you through “smoots”, “garns” and other weird and wonderful units that usually go under the radar.
Plus there’s the usual great mix of reviews, careers and the ever-popular Lateral Thoughts page.
Remember that if you’re a member of the Institute of Physics, you can read the whole of Physics World magazine every month via our digital apps for iOS, Android and Web browsers. Let us know what you think about the issue on Twitter, Facebook or by e-mailing us at pwld@iop.org.
For the record, here’s a run-down of what’s in the issue.
• Celebrating a century of progress – Physics Uspekhi was set up 100 years ago to support the fledgling physics community in the Soviet Union. A century later, the journal’s current editor-in-chief Valery Rubakov talks to Matin Durrani about the future of Russian physics
• Expanding the skills base – Five years after the creation of a multi-institution graduate school for physics PhD students, Peter McDonald and James West outline the lessons learned
• New views on units – Robert P Crease explains why philosophers are fascinated by the redefinition of SI units
• The thing about things – James McKenzie explores how physics and physicists can turn the hype about the Internet of Things into reality
• A brief history of timekeeping – From sticks in the ground to caesium atomic clocks, humans have been keeping track of time with increasing accuracy for millennia. Helen Margolis looks at how we reached our current definition of the second, and where clock technology is going next
• An upcoming change to SI units – due to be officially approved this month – will mark the end of a long journey from defining quantities in terms of objects to using precise, unchanging and universal constants of nature. Benjamin Skuse tells the story
• It’s all smoots and garns – SI units are a scientist’s best friend, but there are also some unusual scales of measurement available. Stephen Ornes looks at the stories behind some of the world’s more weird and wonderful units
• Here comes the Sun – Hamish Johnnston reviews The Sun: Living With Our Star at the Science Museum, London
• Hawking’s manifesto for science – Matin Durrani reviews Brief Answers to the Big Questions by Stephen Hawking
• Computing memories – Margaret Harris reviews The Cryotron Files: the Strange Death of a Pioneering Cold War Computer Scientist by Iain Dey and Douglas Buck
• Skills for start-ups – Entrepreneur and physicist-for hire Volker Türck reveals histips and tricks for setting up a successful business
• Once a physicist – meet Anand Kamalakar, a Brooklyn-based documentary film director, producer and editor whose work includes Salam – The First ****** Nobel Laureate
• Physics and art in 2½D – Sidney Perkowitz on a new kind of art-form
