When optical beams, consisting of photons, travel through fibers, they cause vibrations that generate acoustic waves, consisting of phonons. The phenomenon, called Brillouin scattering, has been harnessed by researchers to optomechanically “couple” acoustic waves with light waves. This coupling allows information carried by photons to be transduced, or converted, to the phonons, which travel nearly a million times more slowly than light waves.

Opto-acoustic coupling has enabled researchers to read and manipulate the transduced information more easily. To date, however, many of the Brillouin scattering techniques researchers have used rely on standard fiber geometries that cause acoustic waves to die out quickly, limiting the efficacy of the coupling.

Now, using an optical fiber with a micron-sized waist, University of Rochester researchers have demonstrated how to couple propagating optical waves and long-lived acoustic waves, with strong optical-acoustic interactions.

We are at a *very* unique moment—on the cusp of a revolution that will usher in multiple trillion-dollar companies and industries.

This moment reminds me of a few other periods filled with disruption and opportunity:

To be a victim of change is to ignore its existence.

A small, globe-trotting balloon declared “missing in action” by an Illinois-based hobbyist club on Feb. 15 has emerged as a candidate to explain one of the three mystery objects shot down by four heat-seeking missiles launched by U.S. Air Force fighters since Feb. 10.

The club—the Northern Illinois Bottlecap Balloon Brigade (NIBBB)—is not pointing fingers yet.

But the circumstantial evidence is at least intriguing. The club’s silver-coated, party-style, “pico balloon” reported its last position on Feb. 10 at 38,910 ft. off the west coast of Alaska, and a popular forecasting tool—the HYSPLIT model provided by the National Oceanic and Atmospheric Administration (NOAA)—projected the cylindrically shaped object would be floating high over the central part of the Yukon Territory on Feb. 11. That is the same day a Lockheed Martin F-22 shot down an unidentified object of a similar description and altitude in the same general area.

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Sketches found inside Leonardo da Vinci’s sketchbooks, show that he had already grasped the essence of Einstein’s 1907 ‘Equivalence Principle’ centuries before the physicist.

Renaissance polymath Leonardo da Vinci demonstrated frictional forces slow down the motion of surfaces in contact. Friction, he determined, is proportional to normal force. When two objects are pressed together twice as hard, friction doubles.

“We see this principle with tectonic plate boundaries,” says Utah State University geophysicist Srisharan Shreedharan. “As surfaces slide against each other, we observe frictional properties, including frictional healing that describes the degree of fault restrengthening between earthquakes. However, we know little about how this phenomenon may affect future slip events, including earthquakes.”

He and colleagues Demian Saffer and Laura Wallace of the University of Texas at Austin, where Shreedharan was previously employed as a postdoctoral fellow, and Charles Williams of New Zealand’s GNS Science geoscience research institute, publish findings about ultralow frictional healing and slow slip events along the Hikurangi tectonic plate boundary in the Feb. 17, 2023, issue of the journal Science.