Category Physics

The invention of the printing press revolutionized duplication of the written word, giving the hands of tired scribes a break and making written material more accessible. A similar breakthrough has happened in reverse in the McKelvey School of Engineering at Washington University in St. Louis.

Researchers working with Chuan Wang, associate professor of electrical & systems engineering, have developed ink pens that allow individuals to handwrite flexible, stretchable optoelectronic devices on everyday materials including paper, textiles, rubber, plastics and 3D objects. Flexible optoelectronics for emitting and detecting light, which are already found in everyday objects like smartphones and fitness trackers, can bend, fold and flex while maintaining functionality.

In a paper pub...

A classic movie was once promoted with the punchline: “In space, no one can hear you scream.” Physicists Zhuoran Geng and Ilari Maasilta from the Nanoscience Center at the University of Jyväskylä, Finland, have demonstrated, on the contrary, that in certain situations sound can be transmitted strongly across a vacuum region!

In a recent publication they show that in some cases a sound wave can jump or “tunnel” fully across a vacuum gap between two solids if the materials in question are piezoelectric. In such materials, vibrations (sound waves) produce an electrical response, as well, and since an electric field can exist in vacuum, it can transmit the sound waves across...

Everyone has, at one time or another, experienced how dreams can influence our moods and actions. However, putting an idea in somebody else’s head while they are dreaming in order to make them do something specific once they wake up is still the stuff of science fiction. In the 2010 movie “Inception,” Leonardo di Caprio’s character tries to get the heir of a wealthy businessman to break up his father’s empire. To do so, he shares a dream with the heir, in which through clever manipulation, the heir’s convictions about his father are subtly altered, leading him to abandon his late father’s business.

While sharing dreams and planting s...

We often believe computers are more efficient than humans. After all, computers can complete a complex math equation in a moment and can also recall the name of that one actor we keep forgetting. However, human brains can process complicated layers of information quickly, accurately, and with almost no energy input: recognizing a face after only seeing it once or instantly knowing the difference between a mountain and the ocean. These simple human tasks require enormous processing and energy input from computers, and even then, with varying degrees of accuracy.

Creating brain-like computers with minimal energy requireme...