Archive for March 15th, 2010

Physics usually progresses by getting new experimental data. Given this data, we refine the theories and eventually we can come up with a picture of how the universe works. However, experimental results can be tricky to interpret. Usually, data is presented as evidence for something, but that depends many times on the model of the noise that is expected.

My most recent encounter with this aspect of physics was the recent paper on dark matter detection by the COGENT collaboration.

The paper states that they see evidence for dark matter in their results. A lot of evidence as a matter of fact. This is from a trial run on a new low noise technology before a full detector is commissioned. Being naturally somewhat skeptic, I raised my right eyebrow a bit more than usual and I hurried one floor down to the High Energy experimentalists to ask how should these new results really be interpreted: is it evidence? Or is it possible that the data reported is a bit too optimistic?

Part of the problem is that when I see the graphs, it is not obvious to me what to look for: this is mostly because I don’t usually deal with this type of data. This is when having colleagues who understand these issues can help a lot. Their expert advice really counts for something. I thought it would be a good idea to share some of this information. (more…)

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