MODERN physics has two tales to inform about our universe. The first says it’s basically made from space-time: a steady, stretchy material that has ballooned because the daybreak of time. The different says it’s basically made from indivisible issues that may’t determine the place they’re, and even when.
Both tales are compelling, describing what we observe with unimaginable accuracy. The huge distinction, although, is the dimensions at which they apply. Albert Einstein’s idea of normal relativity, which describes gravity, area and time, guidelines over very large objects and cosmic distances. Quantum physics, in the meantime, governs tiny, sprightly atoms and subatomic particles.
Ultimately, each tales can’t be true. Nowhere is that this extra obvious than on the huge bang, the place every part within the universe was compacted into an infinitesimally small level. Here, you want a single idea that encompasses gravity and the quantum realm. “Why we’re here is the big question,” says Toby Wiseman, a theorist at Imperial College London. “It seems that quantum gravity is the only answer.”
Alas, it’s a solution we are but to search out, regardless of many many years of looking. Quantum gravity means a reconciliation of the continual and the indivisible, the predictable and the random. There are many concepts, however none can completely incorporate every part. “We’re still no better off at understanding the beginning of space and time,” says Wiseman.
Most physicists trying this start with quantum physics, the workhorse of which is quantum subject idea. This describes three of the 4 forces of nature – electromagnetism, the robust nuclear power and the weak nuclear power – by “quantising” them as force-carrying elementary particles. It …