The Basic Physics of the Kilogram’s Fancy New Definition

The kilogram is now based on energy changes in the quantum world rather than a physical object. Here’s how that works.

The Unseen Victims of the Opioid Crisis Are Starting to Rebel

The push to end opioid abuse has ended up hurting the people who use the drugs legitimately. Now those chronic pain patients are starting a movement of their own.

Abortion Bans Create a Public Health Nightmare

Making abortion mostly illegal will kick off an unintentional, vast experiment in public health—one where the outcomes are sick or dying women and children.