One of the great unsolved problems of modern physics is coming up with a theory of everything — a single, all-encompassing framework that explains and ties together all the physical aspects of the universe. We have yet to reach this lofty goal.
While some physicists continue to strive toward this kind of grand unification of our knowledge, others think that a theory of everything will forever be out of reach — not because the universe isn’t completely orderly, but simply because the tools we use to measure the universe are limited.
“The notion that we can actually come up and have a theory that explains everything assumes that we can know everything,” says Marcelo Gleiser, a theoretical physicist at Dartmouth College, in an interview on On Being.
In order to build a theory of everything, we would need to measure all that there is to measure, which Gleiser says is not possible given our current tools. And even if you could come up with that kind of grand theory based on our current understanding, he says eventually a new discovery would come along that doesn’t fit with your theory — which means it is no longer a theory of everything.
Gleiser is not overly concerned about the inability of physics to tie everything together, because a universe that could be summed up with a theory of everything would be a completely static universe, which is not what we see around us.
“When we look at the whole universe, it is expanding, it’s growing, it’s changing in time,” says Gleiser. “I look at things much more as a state of flux, of becoming, of transformation, than something that has some static truth behind it.”
Gleiser goes on to talk about the way in which we can know the world or even the universe, with science just one of several possibilities for observing, hypothesizing and pondering. In fact, getting locked into one way of seeing — even if it is science — can be detrimental.
“Once you adopt that there is only one way of understanding the complexity of things,” says Gleiser, “you’re just emptying humanity of its value, of the plurality of visions.”
There are other ways of knowing, he says, and to claim that there is only one diminishes the “richness of human culture.” These other ways include the creation stories that occur in every culture, from the something-from-nothing story of Genesis, to the cyclical universe of the Hindu vedic cosmology, to the world being created from the flesh of a primordial being as in Nordic mythology.
Gleiser’s fellow guest, Marilynne Robinson, a professor emeritus of the University of Iowa Writers’ Workshop, points out that many ancient cultures had a “general perception or intuition” that there was a beginning. “That’s a profound intuition that did not burst upon modern scientific sensibilities until Irwin Hubble, until the 20th century,” says Robinson.
Many of these creation stories have parallels in work by 20th century physicists, including the Big Bang Theory. “All the models, the theories that cosmologists use to explain the universe reproduced these mythic ideas,” says Gleiser, who details these connections in his book “The Dancing Universe: From Creation Myths to the Big Bang.”
Modern physics deals not just with the beginning of the universe, but everything that happens afterwards, including how it all fits together, a drive that is very strong among physicists.
“Culturally it’s very enticing for science to come up with this one explanation of everything,” says Gleiser. “And I really trace the roots of that through monotheistic faith.”
But a theory of everything implies a perfect universe — the kind of universe that was once attributed to God, the very embodiment of perfection. But to truly understand the world that we inhabit, we need to embrace its imperfections, of which there are many, including imperfections in how we measure and describe the universe.
“We need to look at the imperfection if you really want to get at things,” says Gleiser, “and give up the notion that there is this beautiful perfection behind everything.”
For Gleiser, science is just one way of understanding the universe, a method that is not entirely different from certain religious experiences. In fact, he thinks it is a mistake to put science and spirituality in separate boxes.
“To write equations on a blackboard and to come up with models about how nature works is, in a sense, a form of worship of that spirituality,” says Gleiser.
There are, of course, limits to what science can help us understand, including physics. Gleiser says that physics has traditionally worked well when teasing apart the motions and actions of stars and galaxies, but this sort of reductionist approach fails when you turn inward to look at the mind or brain.
This failure is not a failure of physics but of the tools currently at its disposal. “We need a different kind of explanatory, descriptive tool because the way we have dealt with things just won’t work for the brain,” says Gleiser.
In the end, though, the inability of science to develop a model for consciousness — or a theory of everything — doesn’t diminish our journey toward greater understanding.
”It’s the asking of the question that is the mystery,” says Gleiser, “not so much how you find the ways to answer it.”