Another Day in Paris

We are still in Michigan. Today we got an introduction the the Umich Center for Ultrafast Optical Science. They have a laser that is capable of achieving the highest intensities of any laser in the world. The idea of the laser is to take a short pulse, then pass it through a series of optical components that induce a chirp. This has the effect of broadening out the pulse. Then the broader pulse can be amplified and the pulse can be made into a short pulse again. The reason that this technique is necessary is because if you just start with a short pulse and try amplify them, the pulse becomes too strong for the amplifier. So in this method of chirped amplification, the pulse is broadened out and amplified. Since the pulse is broadened, any one place doesn't have a particularly high energy.

I thought that this was a cool device because it is able to probe new properties of materials by subjecting them to a high electric field. We also talked about lab safety today and got to see the laser described above. This laser has the acronym HERCULES. I find it amusing that they choose such acronyms.

One issue that I have had with a lot of physics research that I have seen is that it seems like a large amount of attention is given to achieving new extremes: lower temperature, higher pressure, higher intensity, etc. It is hard for me to see that just increasing the strength of our tools really gives us practical knowledge. I asked on of the professors about this issue. He gave a satisfying response. He noted that for this particular area of high intensity lasers, they are reaching the point where the laser could induce pair production in vacuum. That is to say, if you take a space with nothing in it, and subject it to a very large electric field, then an electron-positron pair emerges from seemingly nowhere. I am not sure if this is correct, but it seems that the energy from the electric field goes into creating the electron and positron. This raises the question: if we have a vacuum, do is there actually nothing there? From this, it seems like an electric field does count as something there.

Tomorrow, we are going to be making a hologram. I am looking forward to this. We also are going to be giving presentations about what we think our research is going to be about. The other students seem to be saying that they haven't gotten to reading the papers that their research mentors sent to them. I find it a bit strange that people wouldn't be more responsible about this. However, I am sure that people will get on top of their work.

Besides that, I have been having a good time meeting all of the other students and hanging out with them. Among other things, I hung out with people and tossed a Frisbee around. I do hope to get some more exercise during the trip. Some of the other guys are interested in Frisbee and apparently there is an exercise room at the place where we are staying. We also went out as a group to a Mexican restaurant and had a good time. I definitely feel like I have meet a group of people with whom I would enjoy doing a lot of site seeing. It seems like a bunch of people really want to go see as many countries as possible during their time in Europe. Personally, I would enjoy visiting two or three places and then spending the rest of the weekends in Paris. I think that if we are traveling every weekend, it will get tiring and we won't actually get to see a lot of stuff in the countries that we are visiting. However, we will see how this pans out.

Overall, I am very excited about my trip and the people that I am with. I am looking forward to a great summer.