PODCAST: Once fringe and futuristic, this renewable energy shines brightly today as a cheap and efficient source of energy. Still, it remains controversial — for much different reasons.

PODCAST: Replacing or assisting the human heart with a machine would save countless lives. But the quest to build an artificial heart has had many gruesome missteps and caused researchers to reimagine how to keep our blood flowing.

Traffic planners, securities traders and military strategists all use it. Simulating the behavior of millions of idiosyncratic individuals also may be the best way to understand complex phenomena like pandemics.

Machines might better understand our commands if they experienced our physical worlds, researchers say. That enhanced perception could sharpen their listening skills and improve performance.

The unlikely marriage of two major artificial intelligence approaches has given rise to a new hybrid called neurosymbolic AI. It’s taking baby steps toward reasoning like humans and might one day take the wheel in self-driving cars.

When polymers prove resistant to recycling, new chemical techniques can do the job of breaking them down for reuse

Modern industry has made great strides in turning trash into tomorrow’s new products, but the process is still a long way from perfect. New technologies can help. Plus, updates on chemical recycling, design for recycling and dirty recycling.

The controversial technology of reflecting sunlight away from the planet could help blunt the worst impacts of climate change

Researchers and companies are harnessing computers to identify the emotions behind our written words. While sentiment analysis is far from perfect, it manages to distill meaning from huge amounts of data — and could one day even monitor mental health.

Machine learning has found uses in fields as diverse as particle physics and radiology, and its influence is growing. But so is the understanding of its limits.