Science Seen

Time One author Colin Gillespie helps you understand the physics of your world.

Until recently our cosmic neighborhood was growing faster than the speed of light. Now it’s run into a roadblock.

“From a physical point of view everything that is outside our neighborhood is pure extrapolation.” – Willem de Sitter (1932) Physics is coming up against two fundamental limits: It can never observe the biggest and the smallest things that it needs to study. Some seem satisfied this is the end of our search for ultimate […]

An amazing birthday present: a universe that allows time travel and helps us understand our existence

In 1949 Austrian-American logician Kurt Gödel gave a friend a strange birthday present: a rotating universe. Gödel is widely regarded as the world’s greatest logician. Albert Einstein, the greatest physicist, was his best friend. For years they walked home from the Princeton Institute for Advanced Study almost every day. The present—for Einstein’s 70th birthday—dealt with […]

What is Planck-scale physics and why does it matter?

The Planck-scale physics story begins long ago. In 1901 German physicist Max Planck publishes an explanation for strange properties of radiant heat. He says its energy is quantized. In other words, it radiates in distinct little bits. He sees this as a mathematical convenience and doesn’t really believe it. His math requires a constant he […]

Twin mysteries: A ghostly fundamental particle and a physicist who disappeared after saying its antiparticle may not exist

Twin mysteries arose around 1937 when Italian theoretical physicist Ettore Majorana suggested neutrinos are their own antiparticles. Soon afterward he took the night ferry from Palermo to Napoli and vanished, leaving us to ask: What happened to him; and was he right? The Standard Model has a place for every known elementary particle. It says […]