Two Big Questions Physics Isn’t Addressing
One of the reasons I chose not to pursue a career in science was a feeling that all the interesting problems of physics have been solved. In a sense I still believe this — I don’t see the current line of pursuit bearing much fruit. But I do see two really important questions that physics hasn’t answered. What makes them especially interesting is that most of the scientific establishment doesn’t even recognize them as valid questions.
Ever since Maxwell unified the theories of electricity and magnetism in
1864, physicists have been working towards a single model that can explain all observed forces. It took another hundred years or so for
us to understand how the electromagnetic and weak nuclear forces are really the same thing, and a grand unified theory is close to merging in quantum chromodynamics (QCD) and the strong nuclear force. The only thing left now is to merge in gravity. String theory is a popular contender for a so-called “theory of everything” which explains quantum gravity. Progress here is slow, but finding a theory which combines general relativity and quantum mechanics is widely regarded as one of the big unanswered questions in physics. Personally, I’m not all that excited by it. I think we have bigger fish to fry.
Let’s say we find a Theory of Everything that explains quantum gravity in addition to merging electricity, magnetism and the strong and weak nuclear forces. What changes when we figure this out? Of course, we
can’t really know until we have the answer. But consider the merging
of the electromagnetic force and the weak magnetic force into the
electro-weak force. They look different under just about every condition we will ever encounter. It’s only when the temperature exceeds about 10^15 Kelvin that they start to look the same. For comparison, the middle of the sun is relatively frigid at 10^7 degrees. So my guess is that when we figure this out, it isn’t going to lead to any new
practical understandings about the world around us.
The theoretical basis for most everything that we experience on a daily basis was figured out in the early 20th century with quantum mechanics. It provides a theoretical foundation which reduces essentially all of chemistry to solving mathematical equations. Admittedly these are horrendously difficult equations that even modern computers can only approximate for relatively small molecules. But the theory is there. And with chemistry solved, we have a theoretical basis for all of biology, and everything to do with life. Not to say there aren’t interesting problems to solve there and plenty we don’t understand, but on some level, it’s all applications of an understood theory.
I completely realize this is a simplification of the state of science,
but this is what I thought when I was an undergrad. This realization
and disillusionment drove me away from science towards my career in
software, which I love because of its ability to directly improve people’s lives on a massive scale.
But now as I write about things like the fate of humanity, the nature of consciousness and how to save the world, I see two huge gaps in what science can explain. For context, here’s a quote that I love:
The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it!) but ‘That’s funny …’
Whoever finds the Higgs Boson, or explains quantum gravity will yell “Eureka!” at the top of their lungs. Two things that make me say “that’s funny” about about how physics explains the world today are:
- quantum randomness
- the big bang
I’ll spare the details for now and write more on each of these later. (I’ve written some about quantum randomness and the nature of free will before.) But for now I’ll summarize by saying these are a couple of areas where the standard explanation really doesn’t sit well with me. Moreover, I think a better understanding of these issues would do a lot to answer questions that have troubled humanity since the birth of consciousness.