A scientific team at Caltech thinks that space and time may be made up of “spacetime pixels,” rather than being as smooth and continuous as they seem.
Frog Adhikari, a physics professor at Caltech, suggested in a new press release that these pixels would be really small. How much? Very. “So small that if you were to magnify things so that they were the size of a grain of sand, then the atoms would be the size of galaxies.”
The goal of this Adhikari theory is to bring together the established rules of physics, as governed by general relativity, with the more complex realm of quantum physics.
Can gravity be broken down?
The fascinating theory ofuniverse made of pixels also aims to demonstrate whether gravity can actually be broken down into its basic components. A difficult topic even for quantum physicists themselves! The field, yet to be explored, is called "quantum gravity".
“There are times when science communication mistakenly considers quantum mechanics and gravity to be incompatible,” he says Cliff Cheung, a theoretical physics professor at Caltech who is working with Adhikari. “But if we can do quantum mechanical experiments on this planet, which has gravity, evidently the two things are consistent. Problems arise when you ask subtle questions about black holes or try to merge theories at very short distance scales,” Cheung added.
Even photons like pixels?
In other words, if we could "zoom" into spacetime would we find the individual photons that form light, according to quantum mechanics? Or would it be a continuous spectrum?
Some scientists believe that smaller-scale gravity is composed of single, hypothetical “gravitons,” an element of string theory that resonates at a particular frequency.
And on an even smaller scale? Would we come (we will come) to unify the laws of general relativity and those of quantum physics?
“When I drop my coffee cup, I wish I could just blame gravity,” Adhikari jokes. “But, in the same way that temperature isn't 'real' but describes how a bunch of molecules vibrate, spacetime may not be a real thing.”