About Emily's Research - Public

My research is in the field known as "cosmology", which means that I study the conditions of the very early universe and the big bang. My specific research field is in what we call the "large scale structure", which means I look at the way galaxies are arranged in the sky today, and try and figure out what that can tell us about the universe 13.6 billion years ago, or about how much dark matter there is in the universe.

Dark matter is a big field of study. To an astrophysicist, dark matter can be thought of as a mysterious "gravitational glue". We can see that there is more gravitational pull in a number of pieces of evidence than we would expect based on visible matter -- but whatever the substance is, it does not interact with light in a way we can detect, apart from via gravity. You may have heard it before, but whatever dark matter is, it makes up about 70% of the mass in our universe!

To the right is a visualization of the dark matter in the simulation CUBE that I work with. CUBE is what we call an "N-body" cosmological simulation, meaning it solves the problem of a large number of massive particles interacting by gravity only. The dark matter clumps in this structure we refer to as "the cosmic web". I've drawn arrows on the image to indicate that the distance between large "clumps" of dark matter is the main thing that allows me to answer questions like "how much matter is in the universe"?