Nuclear deformation and symmetry breaking from an ab-initio perspective

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The nucleus, consisting of protons and neutrons and lying at the center of the atom, is the lynchpin of all elements on Earth. Knowing how those protons and neutrons arrange themselves is important in order to understand our origins. One of the most powerful tests of nuclear physics is how the organization of the protons and neutrons changes as their numbers become imbalanced: when there are many more protons than neutrons (or the opposite). In order to understand this, world-class experimental facilities are being developed around the world. My work will focus on two new facilities based in North America: ARIEL in Canada, and FRIB in the United States. At these facilities "exotic" nuclei will be produced, with large differences in the numbers of protons and neutrons. This will be done by smashing together common nuclei, such as isotopes of calcium and xenon, causing them to break apart into the very rare nuclei which I will study. My research will have two primary focuses: how the shapes of exotic nuclei change, and how protons and neutrons behave relative to one another deep inside a nucleus. The nucleus can contain many tens or even hundreds of protons and neutrons. These "nucleons" can arrange themselves into many shapes, from footballs, to rugby-balls, disks, or even pears. Because these shapes require all of the nucleons to act as one they are incredibly powerful tests of our understanding - we need to know what every single proton and neutron is doing in order to understand the shape. I will measure these shapes for exotic nuclei, helping us understand how the protons and neutrons behave when they are very imbalanced in number. The question of how the proton and neutron behave relative to one another inside a nucleus is something else I will investigate. As nuclear physicists we have found historically that the proton and neutron actually behave very similarly inside the nucleus. This means that a nucleus with five protons and four neutrons behaves very similarly to a nucleus with four protons and five neutrons, which is a remarkable result. What I will investigate is how well this behaviour holds up as we add more and more protons and neutrons to the nucleus. This is a very significant question for a number of reasons, with implications for our understanding of how elements evolve when stars explode.Nuclear physics is a very exciting field, with a number of open questions. The incredibly powerful next-generation facilities that I will be using will shed light on a number of these questions and, in all likelihood, open up a number of new exciting ones in the process.