The Independent’s journalism is supported by our readers. When you purchase through links on our site, we may earn commission.

Graphene inventor solves 150-year-old sand castle mystery

The ‘impossibility’ of the 1871 Kelvin equation has finally been proved

A 150-year-old physics mystery relating to sand castles was solved in a paper published in Nature
A 150-year-old physics mystery relating to sand castles was solved in a paper published in Nature
Leer en Español

A 150-year-old physics mystery relating to how sand castles hold together has been solved by the inventor of the “miracle material” graphene.

Professor Sir Andre Geim, who won the 2010 Nobel Prize in Physics for his work on graphene, led a team at the University of Manchester to solve a mathematical puzzle that has baffled scientists since it was first proposed by Victorian physicist Lord Kelvin.

The Kelvin equation centres around a natural phenomenon known as capillary condensation, which is the process that causes water molecules to bind grains of sand together when wet.

This form of microscopic condensation is fundamental to common physical processes like friction and adhesion, but until now physicists were forced to rely upon the incomplete Kelvin equation that only explains binding forces on a macroscopic level.

“Capillary condensation, a textbook phenomenon, is all around us – and such important properties as friction, adhesion, stiction, lubrication and corrosion are strongly affected, if not governed, by capillary condensation,” Professor Geim said.

In order to prove the process at a microscopic level, the researchers created artificial capillaries just one atom high that were capable of accommodating a single layer of water molecules.

The breakthrough was published in the journal Nature this week, in a paper titled ‘Capillary condensation under atomic-scale confinement’.

“This came as a big surprise. I expected a complete breakdown of conventional physics,” said co-author Qian Yang.

“The old equation turned out to work well. A bit disappointing but also exciting to finally solve the century old mystery. We can now relax. All those numerous condensation effects and related properties are finally backed by hard evidence rather than a hunch like 'the old equation seems working – therefore, it sould be OK to use it." 

Professor Geim added: “Good theory often works beyond it applicability limits. Lord Kelvin was a remarkable scientist, making many discoveries but even he would surely be surprised to find that his theory – originally considering millimetre-sized tubes – holds even at the one-atom scale.

“In fact, in his seminal paper Kelvin commented about exactly this impossibility. So, our work has proved him both right and wrong, at the same time.”

Register for free to continue reading

Registration is a free and easy way to support our truly independent journalism

By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists

Please enter a valid email
Please enter a valid email
Must be at least 6 characters, include an upper and lower case character and a number
Must be at least 6 characters, include an upper and lower case character and a number
Must be at least 6 characters, include an upper and lower case character and a number
Please enter your first name
Special characters aren’t allowed
Please enter a name between 1 and 40 characters
Please enter your last name
Special characters aren’t allowed
Please enter a name between 1 and 40 characters
You must be over 18 years old to register
You must be over 18 years old to register
Opt-out-policy
You can opt-out at any time by signing in to your account to manage your preferences. Each email has a link to unsubscribe.

By clicking ‘Create my account’ you confirm that your data has been entered correctly and you have read and agree to our Terms of use, Cookie policy and Privacy notice.

This site is protected by reCAPTCHA and the Google Privacy policy and Terms of service apply.

Already have an account? sign in

By clicking ‘Register’ you confirm that your data has been entered correctly and you have read and agree to our Terms of use, Cookie policy and Privacy notice.

This site is protected by reCAPTCHA and the Google Privacy policy and Terms of service apply.

Register for free to continue reading

Registration is a free and easy way to support our truly independent journalism

By registering, you will also enjoy limited access to Premium articles, exclusive newsletters, commenting, and virtual events with our leading journalists

Already have an account? sign in

By clicking ‘Register’ you confirm that your data has been entered correctly and you have read and agree to our Terms of use, Cookie policy and Privacy notice.

This site is protected by reCAPTCHA and the Google Privacy policy and Terms of service apply.

Join our new commenting forum

Join thought-provoking conversations, follow other Independent readers and see their replies

Comments

Thank you for registering

Please refresh the page or navigate to another page on the site to be automatically logged inPlease refresh your browser to be logged in