Like a lot of science, the birth of string theory was messy. Vibrating strings each playing a cosmic note This search for grand unification brings us to string theory. Einstein was searching for a way to unify gravity and electromagnetism until his dying days. The search for this Grand Unified Theory is not new, and many have tried and failed. So, they have searched for one set of mathematics to describe all of the forces, a Grand Unified Theory that will mean that there is less to remember. It also worries them, as they are unable to describe physical processes in situations when the fundamental forces are battling for dominance, such as at the birth of the universe or in the centre of black holes. This situation frustrates physicists as they have to remember two independent sets of mathematics to describe the physics of the universe. And these two methods are completely incompatible. But the other three forces are written in the language of quantum mechanics. Gravity is described by Einstein's beautiful mathematics of curved space and time. At a larger scale, the rest of the universe is a never-ending battle between gravity and electromagnetism. Of these, the strong and weak forces only operate at subatomic scales. It was realised that there were four fundamental forces that underpin the universe: gravity, electromagnetism, strong nuclear force and weak nuclear force. And these new strange physical theories were yielding incredibly accurate predictions for experimental tests.īut despite this success, physicists were unhappy. In 1900, Lord Kelvin apparently retorted that 'there is nothing new to be discovered in physics'.īut soon after the dawn of the 20th century, this cosy situation began to fall apart.Įinstein rewrote the very notions of space and time with his special and general theories of relativity, whilst Planck, Bohr and Heisenberg revealed that the world of the very small obeyed the apparently nonsensical rules of quantum mechanics.īy the mid-1900s, our view of the universe had been utterly revolutionised. Scientists thought they understood gravity, electricity, magnetism, heat and gases. Two beautiful, incompatible theoriesĪt the end of the 1800s, physics was riding high. To understand why, we need to step back more than 100 years. Why would physicists, a seemingly sensible bunch, think this is the way the universe operates? These strings are truly tiny, many billions of times smaller than an individual proton within an atomic nucleus.Īnd they vibrate at countless billions of times per second in ten dimensions of space, or maybe eleven. String theory is the idea that everything in the universe, every particle of light and matter, is comprised of miniscule vibrating strings. But are they really fundamental? Have we truly reached the bottom? Over the last century, we've ripped atoms apart, eventually finding electrons and quarks, the fundamental building blocks of stuff.

Our high-school physics tells us atoms, with 90 natural elements building the world around us.

What is the stuff in the universe made of?

Family strings theory