Knocking on Heaven's Door - Lisa Randall [192]
A lot of people prefer to work linearly. But this means that once they are stuck or find that the path is uncertain, their pursuit is over. Like many writers and artists, scientists make progress in patches. It’s not always a linear process. We might understand some pieces of a puzzle, but temporarily set aside others we don’t yet understand, hoping to fill in these gaps later on. Only a few understand everything about a theory from a single continuous reading. We have to believe that we will eventually piece it all together so that we can afford to skip over something and then return, armed with more knowledge or a broader context. Papers or results might initially appear to be incomprehensible, but we’ll keep reading anyway. When we find something we don’t understand, we’ll skip over it, get to the end, puzzle it out our own way, and then later on return to where we were mystified. We have to be absorbed enough to continue—working through what does and does not make sense.
Thomas Edison famously noted that, “Genius is one percent inspiration, ninety-nine percent perspiration.” And—as Louis Pasteur once said—“In the fields of observation, chance favors the prepared mind.” Dedicated scientists sometimes thereby find the answers they are looking for. But they might also find solutions to problems apart from the original target of investigation. Alexander Fleming didn’t intend to find a cure for infectious diseases. He noticed a fungus had killed colonies of Staphylococci he’d been investigating and recognized its potential therapeutic benefits—though it took a decade and the involvement of others before penicillin was developed into a powerful world-changing medicine.
Subsidiary benefits often arise from a reserve of a broad base of questions. When Raman Sundrum and I worked on supersymmetry, we ended up finding a warped extra dimension that could solve the hierarchy problem. Afterward, by staring hard at the equations and putting them in a broader context, we also found that an infinite warped dimension of space could exist without contradicting any known observations or law of physics. We had been studying particle physics—a different topic altogether. But we had both the big and small pictures in mind. We were aware of the big questions about the nature of space even when concentrating on the more phenomenological issues such as understanding the hierarchy of mass scales in the Standard Model.
Another important feature of this particular work was that neither Raman nor I was a relativity expert, so we arrived at our research with open minds. Neither we (nor anyone else) would have conjectured that Einstein’s theory of gravity permits an invisible infinite dimension unless the equations had shown us that it was possible. We doggedly pursued the consequences of our equations, unaware that an infinite extra dimension was supposed to be impossible.
Even so, we weren’t immediately convinced we were right. And Raman and I hadn’t dived into the radical idea of extra dimensions blindly. It was only after we and many others had tried employing more conventional ideas that it made sense to leave our spacetime box. Although an extra dimension is an exotic and novel suggestion, Einstein’s theory of relativity still applies. Therefore, we had the equations and mathematical methods to understand what would happen in our hypothetical universe.
People subsequently used the results from this research assuming extra dimensions as launching points to discover new physical ideas that might apply in a universe with no such extra dimensions at all. By thinking about the problem in an orthogonal way (here, literally orthogonal), physicists recognized possibilities they had previously been entirely unaware of. It helped to think outside the box of three-dimensional space.
Anyone facing new ground has no choice but to live with the uncertainty that exists before a problem is completely solved. Even when starting from a nice solid platform of existing knowledge, someone investigating a new phenomenon inevitably encounters unknowns