Interview with Elliot Nelson, an Expert in Early Universe Physics

Elliot Nelson did his PhD at Penn State, supervised by professor Sarah Shandera, on observable effects of inflation in the early universe and currently he is a postdoc at the Perimeter Institute.


Physics Insider: What are you currently working on?

Nelson: Currently I am learning about nonlinear extensions or modifications of quantum mechanics, including potential observational tests in cosmology. Quantum mechanics is important in cosmology because according to inflation all the structure in the universe has a quantum mechanical origin.

Physics Insider: Why is this important?

Nelson: Combining quantum mechanics and gravity may involve a modification of quantum mechanics as well as quantization of gravity. Quantum superpositions are proven to exist for objects with small masses, but it is not clear whether the superposition principle applies for very massive objects.

Physics Insider: What was the biggest advance/discovery in your field in the last 20 years?

Nelson: The biggest discover has been the accelerated expansion of the universe, in 1998, which likely indicates a very small but nonzero vacuum energy.

Physics Insider: What is your advice to a student who wants to make a career in your field?

Nelson: Explore everything, and find out which topics or questions you are passionate about.  Work on projects that you are excited about and try to make them your own, rather than just doing what your advisor wants you to do.

Physics Insider: If some fairy would offer to answer you one question about nature; what would it be?

Nelson: I have always wondered about prime numbers, and would like to know if there is a simple pattern to the distribution of prime numbers, and what role prime numbers play in fundamental physics. I would also be interested in understanding how emergent or “higher level” phenomena such as consciousness relate to fundamental physics.  What laws of physics could (or could not) give rise to a world with conscious experience?

Physics Insider: How far do you think are we away from answering this question?

Nelson: I don’t know.  Probably very far, for the second one.

Physics Insider: If you could give your 20 year old self one piece of advice, what would it be?

Nelson: Think deeply about what possible career directions you could head in.  Don’t just go in some direction by default, or assume that your passions and talents will express themselves in the way you may think.  Experiment, talk to people.  Think outside the box and find out about career paths you may not know of.  Find out what the greatest needs are in the world, and ask how you can make the biggest difference.  Of course you’ll have to go in some particular direction and may have to give a lot of time and energy to a narrow area of focus, but keep coming up to the surface and asking big questions about yourself and the world.

Physics Insider: Which books do you recommend to someone who wants to do research in your field?

Nelson:  There are good textbooks, but you should especially take advantage of online videos of lectures, and introductory review articles.  For example, Daniel Baumann’s TASI lectures on inflation.  There are some excellent physics blogs as well, eg. Quantum Frontiers, Matt Strassler’s blog, Jess Riedel’s blog, etc.

Physics Insider: Which books did influence you the most?

Nelson:  Perelandra and other books by C. S. Lewis.

Physics Insider: What do you wish you would’ve known earlier in your career/ when you started studying physics?

Nelson: I wish I would have had a better idea of the range of research areas, what the big questions are in each, and how they relate to each other.  This isn’t always taught in classes, and is worth some independent reading.

Physics Insider: Mr. Nelson, we thank you for this interview.

To learn more about Mr. Nelsons’s research, you should have a look at his papers and his personal website. If you liked this interview, have a look at our interview with Michal Malinský, an expert in Grand Unified Theories.