I did this digital painting originally for Higgs-boson but it works here as well (Illustration by MC)
My decades-long effort to get a handle on some aspects of quantum physics has essentially become leaping from one failure to the next. Just as I think I have begun to understand a concept it ceases to make sense.
I understand quantum physics philosophically but it is the science of it that eludes me. In my younger days I used to curse under my breath every time I would run into a theory that I did not comprehend. There were days when I would curse in infinite loops of invectives. With age one gets amused by one’s intellectual inadequacies. My current sadomasochistic endeavor is to get some measure of quantum gravity, which is supposed to be the physics for the 21st century just as quantum physics was for the last century.
Yesterday, I posted a nerdy Facebook update saying “Trying to get a handle on quantized gravity” and intend writing a “short piece” about it today. Friend, fellow journalist and fellow nerd Kajal Basu declared with obvious disbelief, “A SHORT piece on quantum gravity? Whoa! After you finish, tell me how it’s done”. He did suspect that that I would take refuge in “la philosophie cynique”. He is not that off the mark because those who don’t comprehend pure physics, philosophize. It is a cop out and I would be the first one to concede it. That said even philosophizing requires at least some peripheral understanding of the subject one is philosophizing about.
The first point I must bear in mind is the “quantizing gravity” does not mean what I would like it to mean, namely that you atomize gravity, bottle it and spray it around. Not as a cologne or perfume but as actual gravity. The idea is that you can make gravity potable and distribute it in whatever measure you want. Imagine going into any corner of the universe with bottled gravity and turning it upside down by altering its gravitational balance by spraying gravity. I don’t know about you but to me it sounds cool.
Coming back to the serious side of quantum gravity, it is now believed that the discovery of primordial gravitational waves means gravity is indeed quantized. Quantize means gravity now has discrete observable value. I hope I am getting this right. In reading a lot of material about this subject I did not come across anything that answered the elementary question—What is quantized gravity? Sure, there are many complex explanation with scientific language and equations that destroy your confidence in yourself.
From what I understand (and I understand very little) gravity has so far stood apart as a force in the classical sense of the word unlike other forces such as electromagnetism which can be seen from the standpoint of quantum physics. There are two main theories of the 20th century physics—quantum theory and Albert Einstein’s theory of general relativity. Quantum theory deals with the microscopic parts of nature such as electrons and photons and how they interact with each other. General relativity describes the force of gravity that controls the macro, the vast bodies in the universe such as planets, stars, galaxies and so on and how they interact with each other. For close to a century physicists have struggled to fuse these two theories that work perfectly well within their respective realms but collide when they come together. The main reason why they collide is because gravity has not been quantized or, in other words, not seen from the standpoint of particles. There has been a longstanding speculation about a particle called graviton which essentially carries the force of gravity. This is a massless particle and hence its range is limitless.
The detection of the primordial gravitational waves indicates gravitons because we have detected those waves some 13.8 billion years after they were generated during the putative Big Bang. It is believed that with this discovery the quest to fuse quantum theory and theory of general relativity has gained tremendous momentum.
I see such high science as the world’s most exclusive club where bouncers are invisible but very much present, checking for a level of intelligence to let you inside where a bizarre world unfolds to the accompaniment of cosmic rhythm and dance. I have been waiting for nearly four decades for entry. So far I have ended up with a kick up my pants. So while I wait, I try and formulate quanta of gravity and bottle them.