Category Physics

The next generation of Harvard’s Ambulatory Microrobot (HAMR) can walk on land, swim on the surface of water, and walk underwater, opening up new environments for this little bot to explore. Credit: Yufeng Chen, Neel Doshi, and Benjamin Goldberg/Harvard University

‘HAMR’ can walk on land, swim, and walk under water. In nature, cockroaches can survive underwater for up to 30 minutes. Now, a robotic cockroach can do even better. Harvard’s Ambulatory Microrobot, known as HAMR, can walk on land, swim on the surface of water, and walk underwater for as long as necessary, opening up new environments for this little bot to explore.

This next generation HAMR uses multifunctional foot pads that rely on surface tension and surface tension induced buoyancy when HAMR needs to swim but can also apply a...

Screenshot of video showing hybrid catalyst for water splitting (see video at: https://youtu.be/nkouqCFaqAk). Credit: Image courtesy of University of Houston

Catalyst uses inexpensive elements and could be scaled up for commercial use. Researchers from the University of Houston and the California Institute of Technology have reported an inexpensive hybrid catalyst capable of splitting water to produce hydrogen, suitable for large-scale commercialization.

Most systems to split water into its components – hydrogen and oxygen – require two catalysts, one to spur a reaction to separate the hydrogen and a second to produce oxygen. The new catalyst, made of iron and dinickel phosphides on commercially available nickel foam, performs both functions.

Researchers said it has the potential to dramat...

Excitation spectra of the Higgs mode

Researchers produce a state in which atoms behave similarly to a Higgs boson. Physicists at the University of Bonn have succeeded in putting a superconducting gas into an exotic state. Their experiments allow new insights into the properties of the Higgs particle, but also into fundamental characteristics of superconductors.

For their experiments, scientists at the University of Bonn used a gas made of lithium atoms, which they cooled down significantly. At a certain temperature, the state of the gas changes abruptly: It becomes a superconductor that conducts a current without any resistance. Physicists also speak of a phase transition. A similar sudden change occurs with water when it freezes.

The lithium gas changes to a more orderly state at its phas...

Range of the size for a typical neutron star compared to the city of Frankfurt. Credit: Lukas Weih, Goethe University, satellite image: GeoBasis-DE/BKG (2009) Google

Comparison of billions of theoretical models with gravitational waves results in the answer to an old riddle. How large is a neutron star? Previous estimates varied from eight to sixteen kilometres. Astrophysicists at the Goethe University Frankfurt and the FIAS have now succeeded in determining the size of neutron stars to within 1.5 kilometres by using an elaborate statistical approach supported by data from the measurement of gravitational waves. The researchers’ report appears in the current issue of Physical Review Letters.

Neutron stars are the densest objects in our universe, with a mass larger than that of our sun comp...