Published 23 June 2010 by Alexander Bastidas Fry

An exceptional time in astrophysics

The confluence of great minds at Lindau is also a meeting of contrasting perspectives. Each scientist has his own specialty in which he is likely the world expert, but each scientist also tries to generalize his work to solve the biggest problems in the world. It seems to be true that scientific research is highly specialized, but always looking for logical deductions about the world as a whole. For example, if you look through the Lindau meetings schedule you will notice that the physics talks are often about astrophysics or cosmology and chemistry talks are about medicine. Particularly, I have been thinking about the inevitable intersection of particle physics and astronomy.

I have often heard people say that we are at an exceptional time in astrophysics or it is the golden age of cosmology. What does this mean? In a previous post Akshat Rathi discussed How the Lindau meeting contributes to the celebration of science and he pointed out that the individuals who are recognized as Nobel Laureates are part of a larger team of scientists. In the modern era one needs the ability to build and lead a good team effectively to be successful in research. I think there are two main reasons it is said we are at an exceptional time in astrophysics. The first is that we have made many successful predictions that have been confirmed by observations so that we now have a consistent story of our universe (the story will be told by John Mather on the first day of Lindau 2010 during his talk on ‘the History of the Universe, from the Beginning to the Ultimate End’). The second reason is that the success and resources of particle physics is now being directed to questions that arose from astrophysics. 
However, it is not certain that ‘big science’ is good for astronomy. Riccardo Giacconi discussed the impact of big science on astrophysics in his 2008 talk at Lindau
Riccardo Giacconi 2008
Riccardo Giacconi, 2008 – 58th Meeting of Nobel Laureates
The Impact of Big Science on Astrophysics
His main point is that changes in technology and other factors have changed the methodology of astrophysics. He mentioned the concept of science system engineering which he described as ‘making the system as simple as you can so that it will work’, whether those adverse conditions are from the conditions in outer space or stubborn project management. The benefits of this big science will be big science questions answered and end to end data systems will produce archives to makes astronomy a flat world, that is everyone will have public access to the data sets produced. Giacconi fears though that this has turned the astronomical community in to consumers of goods instead of makers thus he urges a balance of large, medium, and small collaborations. 
 The bullet cluster
A beautiful result of large science collaborations is the Bullet Cluster which provides some of the best evidence to date of dark matter. The image above is a composite with data from several sources including the Hubble Space Telescope and the Chandra X-ray observatory which are certainly two massive collaborations. Dark matter is one of the driving reasons particle physicists are now interested in astrophysics. The reality is that physicists were always interested in astrophysics, after all, the highest energy particles in the universe come from cosmic rays produced by astrophysical sources. Particle physicists have used cosmic rays for almost a century as a free cosmic particle accelerator to study particles, but now they are joining forces with astrophysicists in massive collaborations.
We all know that whether we call it astronomy, astrophysics, or particle physics our ultimate goal is to understand the cosmos better, so one could argue that the distinction and discussion of the merger of fields is without merit. However, what is important is how scientists decide to invest their resources and time. The wisdom of Nobel laureates being shared with young researchers at Lindau will help us choose the right path.

Alexander Bastidas Fry