MIT TECHNOLOGY REVIEW: The Engineering issue features ‘Go big or go home’. That may be true—sometimes. But, just as often, solving engineering challenges means thinking small. From the tiny transistors powering the AI boom to the machines digging the world’s longest tunnels, human ingenuity is tackling problems at every scale. Plus: A fresh spin on air conditioning, stratospheric cell service, and more.

The $400 million machine powering the future of chipmaking

The AI era needs ever faster chips. ASML has a monopoly on the expensive contraptions needed to pattern them. Can anyone catch up?

Hacking the atmosphere: Geoengineering gets a reality check

Researchers are starting to explore the tools and systems we need to develop to cool down the planet.

Want to get a data center online quickly? Give it some flex.

As the data-center boom puts pressure on the grid, some companies say the answer isn’t just more power plants but software that dials down centers’ energy-guzzling ways when demand spikes.

The search for dark matter has been blown wide open

After decades of hunting, physicists still don’t know what makes up most of the universe’s matter. Now they need to cast a wider net.