Tres físicos no hispanohablantes

Can't you see the dark matter? This is about how much we know about what dark matter is.

As you may or may not know, there is a problem in the field of cosmology which is that the mass in the universe that we can observe does not add up to what we would expect based on other observations. To explain how galaxies clump and stars move around in their galaxies, additional mass, called ‘dark matter’ is required.  It is called ‘dark’ because it doesn’t give off light.  The only problem is that because we can only observe it indirectly, no one really knows what this stuff is.  Consequently, we don’t know how to write down the necessary equations that explain it’s gravity.

Well, there is a possible solution to this problem that Martin and I have been looking at for the last couple weeks. There is a newly proposed theory of gravity by Petr Horava, which includes non-relativistic properties, such as faster than light travel for incredibly short distances.  In this theory, time and space, are treated unequally, which leads to an extra term that appears in our solutions.  This term acts like cold dark matter (cold because it’s not self-interacting). Here is the paper that explains the theory if you would like to read it: arxiv.org/abs/0905.3563. The whole situation is very exciting and we hope to find out more about it.

Pretty picture of the origin of the universe

The Alexander Group is traveling to Santander, Spain to collaborate with researchers at the Instituto de Fisica de Cantabria (IFCA). While we are there we will be collaborating with professional astronomers, cosmologists, and nonlinear physicists on two projects. Collaborating with Dr. Jose Diego, Dr. Alexander and Garrett are exploring parity properties of the cosmic microwave background data. Under Dr. Alexander, Martin and Alex will be exploring the properties of fermionic fields in alternative formulations of general relativity. We will used this blog to report on our adventures leading up to and during the trip.