The biggest question: What next?

From the limits of experiment to the need for better data analysis, Convergence closing panel looks at a future of great challenge and greater potential.

In fundamental research about the universe, “I don’t know” is an acceptable answer. In fact, it’s the most exciting answer. 
“I’ve never come across a group of people so excited about not knowing something,” said Ian O’Neill, Space producer at and moderator of the closing panel at Convergence. 
It’s not that there’s a shortage of knowledge in fundamental physics; in terms of empirical data, there is more than ever, thanks to experiments like the LHC and the Planck satellite. 
What’s especially exciting about all subfields explored at Convergence – particle physics, quantum information, cosmology, and many more – is how much is still waiting to be known, and how tantalizingly close we are to some discoveries. 
As Einstein said: “To raise new questions, new possibilities, to regard old problems from a new angle, requires creative imagination and marks real advance in science.”
Creative new questions were the unifying theme of the panel discussion, which brought to a close the official proceedings of the inaugural Convergence conference, which explored the big-picture questions expected to fuel 21st century physics. 
Though their individual subfields diverge in terms of tools and techniques, the same underlying questions – What are we missing? What puzzles remain? – motivate panelists Patrick Brady, Stefania Gori, Immanuel Bloch, and Sara Seager. 
“We have found the Higgs boson – the question now is what’s next?” said Gori, a postdoctoral researcher at Perimeter. “I think dark matter is a big question for particle physics in the next years. What is it, and how do we find it? With all these challenges, it’s a really exciting time for the field.”
For Immanuel Bloch, whose work with ultra-cold atoms is revealing unprecedented glimpses into the quantum realm, the excitement lies in new insights coming from other branches of physics. 
“We’re in a remarkable time in quantum many-body systems, as we’re seeing a convergence of many fields coming together,” said Bloch, scientific director of the Max Planck Institute for Quantum Optics.  “These are not only theoretical concepts we’re using to characterize these systems – we now have the ability to work with these things in the lab.”
That convergence of theory and experiment is particularly exciting for Patrick Brady, director of the Center for Gravitation, Cosmology and Astrophysics at the University of Wisconsin-Milwaukee. His work focuses on gravitational waves, which have been a theoretical concept for decades and are now on the verge of detection. 
“We are on the edge of an exciting era of gravitational wave astronomy,” he said. “We just don’t know what we’re going to see, and that’s the cool part of it.”
Seager, too, said the search for exoplanets is an the midst of accelerating progress, though she cautioned that the kind of space telescopes needed to truly detect inhabitable planets may require the work of future generations.
“It’s not enough to find a planet that might be like Earth – we want to find dozens of planets that might be Earth-like, and even be able to look for signs of life,” said Seager, a professor of planetary science and physics at MIT. “There’s much speculation, because we have no idea how common life is. And what happens then? New space telescopes are often 30 years from launch. I’m just trying to inspire my students. Maybe it’s the people being born today who will (make these discoveries).”
The panel session sparked off a lively wide-ranging question period from the audience – demonstrating again something that has been evident throughout Convergence: the questions are always more important than the answers. 
The audience nodded in agreement as Seager finished up the discussion: “My favourite thing is thinking about the next, newest, most exciting problem to work on. That’s what gets me up in the morning.”
- Colin Hunter