Garrett Lisi. Illustration by Bernd Schifferdecker
Garrett Lisi gets it. The couch-surfing, academia-shunning theoretical physicist grasps something that, for scientists, is possibly more elusive than illuminating the complicated behavior of subatomic particles: balance in life. Don’t want to be stuck in a lab? Get out. Want to travel the world living where you please, doing research in between surfing and snowboarding? Pack your bags. Have a problem with the scholarly journal system? Publish your own papers. To say that Lisi conducts science on his own terms tells only part of the story.
When Lisi published his physics paper, “An Exceptionally Simple Theory of Everything,” to an online archive last year, it created a media buzz about his lifestyle and an onslaught of support and skepticism about his model. Although the verdict is still out on whether Lisi’s theory will prove predicatively accurate, the means by which he released and vetted his research point to a larger trend in the scientific community.
Barriers to data are falling, a cross-disciplinary community of commenters is replacing journal-selected peer reviewers, and “information to the people!” is becoming the raison d’être of the science information superhighway. The movement, combined with an evolving image of the contemporary scientist, is redefining how society interacts with science.
We checked in with Lisi recently for an update on his theory, his thoughts on publishing, and his pursuit of life.
You left academia to study physics on your own. Why?
Freedom. When I got my PhD, I really loved general relativity, quantum field theory, and differential geometry, and I wanted to continue my research in these areas. But at that time the only funded research options available in these combined fields were in string theory, which was and still is the dominant research program in theoretical particle physics. I had learned a bit about string theory, and some things about it are pretty cool, but I thought string models were kind of far-fetched and probably not relevant to our universe. So I took off for Maui — the most beautiful part of the world I could find — and worked on the physics I wanted to, while squeaking by financially. Recently, research grants from small private foundations (FQXi and SubMeta) have allowed me to travel a bit and talk with other physicists, but I still spend most of my time on Maui.
Why isn’t string theory relevant to the universe?
Which string theory? Back in the 80s, string theorists expected the standard model spectrum of particles to come out of the theory naturally, but it never did. Now we have been presented with the idea that there is a landscape of many possible string theories, and our universe is supposed to be in there somewhere. There are some nice things about strings, but no testable predictions come from this jumble of models, and there is no single realistic string model that can be held up for our inspection. String theory has been getting a lot of heat lately, and I don’t need to add fuel to the fire. Peter Woit and Lee Smolin have written excellent books describing some of the problems with the string theory program, both technical and sociological. My own views on the technical problems with string theory won’t add anything new to the argument. I think scientists should be able to weigh the pros and cons of different theoretical models for themselves and follow what interests them, without pressure in one direction or another.
Why did you choose not to submit your paper to a traditional peer-reviewed journal?
I think peer review is important, but the journal-operated system is severely broken. I suspected this paper would get some attention, and I chose not to support any academic journal by submitting it. Under the current system, authors (who aren’t paid) give ownership of their papers to journals that have reviewers (who aren’t paid) approve them before publishing the papers and charging exorbitant fees to view them. These reviewers don’t always do a great job, and the journals aren’t providing much value in exchange for their fees. This old system persists because academic career advancement often depends on which journals scientists can get their papers into, and it comes at a high cost — in money, time, and stress. I think a better peer-review system could evolve from reviewers with good reputations picking the papers they find interesting out of an open pool, such as the physics arXiv, and commenting on them. This is essentially what happened with my paper, which received a lot of attention from physics bloggers — it’s been an example of open, collaborative peer review.
What is the alternative to the way problems in physics are typically approached?
I don’t think there is a typical way physics is being done; there’s a great deal of variation. But there does seem to be more pressure on young researchers than there should be, especially on post-docs and new professors. Science shouldn’t be a grind to publish more papers and advance a career — we’re supposed to be doing this because we love it and find it fascinating. High-quality work and interesting projects should be valued, not just a lengthy publication record. And since science helps society, I think society should be better to scientists and support them in doing the research they want, rather than requiring them to jump through so many hoops.
How do you respond to those who question the validity of your methodology and are skeptical about the assumptions necessary for your theory to work?
I welcome criticism and skepticism, and I encourage people to look through the mathematics for themselves. I’ve done my best to make everything as transparent as possible, and I try to be up front about the problems this theory still has. Some of the techniques I used confused people at first, because they hadn’t seen them before, and this led to some ill-considered criticism. But these techniques were based on solid work done in the 70s. I’m actually extremely conservative in the mathematical structures I use, and in the assumptions I’m willing to make.
How will “open science” and other new ways of sharing information transform science?
I think we’re in the midst of a gradual revolution, following the rise of the Internet. The success of the physics arXiv — where physicists post freely available versions of their papers — has made it possible for anyone to access the literature from anywhere. This let me move to Maui 10 years ago and stay in touch with the field. Now an NIH mandate, requiring that publicly funded papers be posted to PubMed, will produce the same liberating effect in other fields. The net is also affecting the way scientists work directly, with wikis and blogs used for discussions, collaborations, and individual note keeping. These new tools, along with online social networks, allow geographically independent researchers to keep in perpetual, productive contact. Since theoretical researchers are no longer anchored to one location, I’ve been working on creating Science Hostels — micro-institutes in beautiful places where scientists could live and work, while having a bit of fun, and keeping more of a balance in their lives.
What is exceptionally simple about your unified theory of particle behavior?
Well, the “exceptionally simple” title is a pun, but the theory is simpler than alternatives. The main idea came from playing with different formulations of general relativity and particle physics until I found a way to get them together in a single mathematical structure, called a superconnection. I was especially happy to find how easily the Higgs field fit in this structure. And I was even happier when the whole algebra of the standard model and gravity fit into the algebra of the largest simple exceptional Lie group. In graduate school we learn about spinor fields (describing electrons) as matrix columns of complex numbers, transforming algebraically in a certain way. But why should nature care about matrices or algebra? From the success of general relativity, we know nature cares about geometry. And these exceptional structures allow the algebra of spinor fields to be described in terms of the pure geometry of Lie groups. It makes for a very consistent and elegant description.
How does that group, referred to as E8, inform your theory, and is its structure really “in everything,” as stated by media?
In this E8 theory, it’s more accurate to say “everything” is in this particular Lie algebra. Three years ago I had gathered all known fields into one mess of algebra, describing particle interactions. This algebra included bosons interacting with fermions, and it looked unlike any Lie algebra I’d ever seen. It was a long time before I even considered that it might be part of some larger mathematical structure. Then one day I decided to look and see, and almost immediately found that it perfectly matched part of E8 — a truly beautiful mathematical object. It was a stunning realization. I had no reason to suspect that the collection of algebraic fields I had put together was actually part of a single mathematical object. And this object also seemed to have the two missing pieces I was looking for. So, to find it all fitting together like that, all at once — it was a bit overwhelming for me. One doesn’t get many days like that.
Originally published November 17, 2008