Can we craft a theory in which space and time aren’t assumed to exist?
While quantum mechanics deals with reality in discrete, granular fashion, relativity tells us that space-time, and therefore gravity, is continuous and non-discrete. The mathematics produced myriad discrete geometric objects, including loops, lattices, and polygons, arranged in various constructions called spin-networks and spin foams. Their simultaneous existence generates a paradox, meaning physics is, in a sense, in disarray. Oriti told Ars that, at that time, emerging ideas about black holes focused on using quantum mechanics to describe the matter fields around them. New approaches to quantum gravity, like LQG, began to emerge during this period. In LQG we call these basic entities spin-networks, which are discrete, algebraic objects. Since we know the world is quantum, general relativity must be an approximation of an underlying quantum description of space-time itself.
Over the past decades, a field of physics has developed that postulates the existence of mysterious algebraic entities called spin networks. These networks—proposed as the constituent stuff of space and time—condensed to produce the Universe as we know it. That condensation resulted in the event that we currently call the Big Bang, giving the field its name: condensate cosmology.
The idea, technically termed “Group Field Theory (GFT) condensate cosmology,” is a branch of quantum gravity, a field of physics that aims to establish the fundamentals of what everything from light and matter to space and time is made of. It is an idea based completely in theoretical calculations—and it’s totally untested for now. Condensate cosmology requires a great deal of abstract reasoning to even try to understand it.
Despite these challenges, quantum gravity has drawn a lot of attention from some of the sharpest minds in all of physics. Its ideas are bold and daring, highly creative, and extraordinarily imaginative.
Niagaratech 