When Antarctica Just Isn't Cold Enough: South Pole Telescope (SPT) Fridge Cycle

As you might have heard on my website, my newsletter, my Twitter, or, if we’re colleagues at Caltech, at work, I am currently working on the South Pole Telescope (SPT) onsite at the South Pole in Antarctica for January-November 2016 (I am employed by the University of Chicago). I have taken a sabbatical from my NSF Astronomy Read More …

Finding earth like planets from the comfort of our own planet

Gravitational lensing results from the fact that General Relativity describes our universe: mass bends light and can function in effect like a lens, bending light in ways that can be used to infer the mass distribution itself. Gravitational microlensing is due to this same effect, but refers to the detection of objects which are of Read More …

Dynamic Bayesian Combination of Multiple Imperfect Classifiers

Using the new Voxcharta.org system, I was the only physicist at my institute to upvote this paper, Dynamic Bayesian Combination of Multiple Imperfect Classifiers (pdf), more in the realm of machine learning or computer science than traditional astrophysics or astronomy. As such I was nominated to discuss it at our weekly journal club. Here I give a brief review of concepts needed to follow the paper, and then go in depth into how we can use the opinions of multiple lay people as to whether an object is a supernova or not to achieve a highly accurate classification at the expert level. Read More …

The Intersection of Productivity and Joy (over the past months)

Since last we spoke a couple of months ago, I had a hell of a time personally: I moved house, went from one location to another too often, had a major and very stressful financial crisis and had some rough times with friends which rocked the emotional boat. Although there are many things which didn’t Read More …

Probing the dark matter issue in f(R)-gravity via gravitational lensing

A few days ago in gr-qc  journal club we discussed an interesting paper by a member of our own institute, Probing the dark matter issue in f(R)-gravity via gravitational lensing.1. Background Dark Matter We theoretically expect dark matter to exist based largely on  extensive observations of both dynamics (rotation curves and objects such as the Read More …