Tag Archives: string theory

What are the quanta in quantum gravity? A hundred years ago Einstein said “space”. So where are we now?

Quantum gravity is all the rage in physics these days. There are books about it but none say what quantum gravity is. And none report real progress. We should be upset about this. Really! Quantum gravity tries to reconcile our two immensely successful—but mutually inconsistent—theories about the world: quantum theory and relativity. A quantum theory […]

How does Planck-scale physics work?

Planck-scale physics is more than a hundred years old. Physics is starting to take it seriously. This is great because we can hope for exciting new science and technology to drive a new economy. Planck scale is the incredibly tiny scale at which physics actually happens. It is the scale at which space no longer […]

At last an answer: What happened at the Big Bang

What exactly happened when the universe was born? What happened at the Big Bang? is the title of last summer’s popular science exhibition sponsored by six leading British universities and the Royal Society in London. Amid much fascinating information, the exhibition’s answer was: We don’t know. Yet, as Science Seen’s readers will recall, that answer […]

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 […]