Another great autumn week has passed and it’s time once again to take a look at the top news of physics. Here are the top 3 news stories with corresponding links. To receive these news straight to your inbox, register for our email newsletter here.
1. Zero Friction Quantum Engine Designed (Sep 16)
In real physical processes, some energy is always lost any time work is produced. The energy is almost always lost due to friction. Now, a new engine that operates with zero friction has been designed by scientists from Queen’s University in Belfast. The engine is unique in a sense that it makes use of the bizarre laws of quantum physics.
The current theories of classical thermodynamics describe a wide array of topics, however, when it comes to quantum world, thermodynamics might need an upgrade. What a quantum version of thermodynamics might look like is not yet known, and neither are the limitations or possible advantages of the quantum devices that would be described by such laws. The new engine that operates using quantum shortcuts is a little, but significant step towards the direction of quantum thermodynamics.
“This work is one of the first steps into the merging of quantum control and thermodynamics,” said Mauro Paternostro, a co-author of the study. “We have shown that it is possible to use techniques that, to date, have only been used for other goals (population transfer, for instance) for thermodynamic tasks and the engineering of efficient cycles.” The research also marks a step toward the key engineering goal in this context, which is to find the maximum efficiency allowed at the maximum possible power.
2. Banana Peel Slipperiness Wins the IgNobel Prize (Sep 19)
How slippery is a banana? Who cares, you might answer. Well, apparently, Kiyoshi Mabuchi and his colleagues at Kitasato University do care and they got an IgNobel prize for that. Their research investigated how slick that banana peel really is.
To determine exactly how slippery a banana peel is, Mabuchi and colleagues sacrificed a total of 12 Cavendish bananas. They placed the banana skins interior-side down on samples of linoleum and measured the coefficient of friction with a force transducer. It turns out that banana skins are, indeed, very slippery. The average coefficient of friction of a banana on linoleum was 0.066, and friction was only slightly higher for a banana on hardwood flooring (0.083).
One of the cornerstones of the general theory of relativity — the equivalence principle — has recently been tested in the influence of a strong gravitational field. The collaboration of scientists from the University of Amsterdam, University of Leicester, the University of Cambridge and the Swinburne University have measured the mass ratio between protons and electrons at a laser lab and compared the results with the same ratio obtained from the surface of a white dwarf star.
White dwarfs stars, which are in a late stage of their life cycle, have collapsed to less than 1% of their original size. The gravitational field at the surface of these stars is therefore much larger than that on earth, by a factor of 10,000. However, even under such extreme conditions, the proton-electron mass ratio is the same within a margin of 0.005%. In both cases, the proton mass is 1836.152672 times as big as the electron mass. Such a test in a strong gravitational field not only re-confirms that the equivalence principle still holds, but also gives important insights into how gravity works undersuch conditions.
- New Ways to Improve Efficiency of the Solar Cells
- Longer Distance Quantum Teleportation
- Tweak to Dark Matter May Explain Milky Way Mystery