Monday, June 04, 2007

General Exams Begin

I start my general exams today. I think that's what they're called. I've been informed they are definitely not quals or qualifying exams, but I don't understand the difference in semantics, and seeing as how they're just something I have to do, I don't really care either—thought I might again in a month.

As I explained last time in agonizing detail, our department just changed the policy for the exames-taken-after-classes-are-finished. I, like everyone else, chose to do the "new format," which is to say, I'm going to be learning a whole lot about the Lyman-α forest in the next ten days. (It's supposed to be two weeks, but thanks to extenuating circumstances, well, ten days is kind of like two weeks, right?) Then, a little less than two weeks after I turn in a pile of summary papers to my committee, I have an oral presentation scheduled ... on a completely different topic.

I spent today reading the Rauch (1998) review article of "The Lyman Alpha Forest in the Spectra of Quasistellar Objects." ("Quasistellar object" is a back-in-the-day word for "quasar.") Man, review articles are intense. The first review article (fine, it's actually from a lecture series, but anyhow) I ever read was Narayan & Bartelmann's discussion of graviational lensing. For the two years I worked on gravitational lensing (starting from absolutely no knowledge whatsoever), every time I went back to the article, I discovered some little nugget of information that simply hadn't penetrated my skull previously. Hopefully in the last four years I've learned a little bit about how to learn, as well as gained a tad of astronophysical background ...

Let this also suffice as a warning that blog posts might be somewhat more intermittant than usual for the next couple of weeks.


Anonymous said...

hi mollishka, i stumbled upon your blog some time ago (linked from science blogs, i think). upon reading this entry, something clicked - narayan and bartelmann was also my first review article! i have a sneaking suspicion that it is because we shared the same undergraduate research advisor. besides assigning the same introductory reading, this advisor also likes to reuse his e-mails - i was the recepient of several copy-and-paste e-mails addressed to a certain "molly," which confused me at first seeing as that is not my name.

haha well, small world, etc. just thought i'd let you know. good luck with your exams!

Rob Knop said...

Technically speaking, back in the day QSOs and quasars weren't exactly the same thing.

There are a whole slew of names for active galactic nuclei; read the first chapter of Krolik for many of them. Meg Urry told me a few months ago that she's trying to avoid using any names but Quasar and AGN any more, because they're all the same kind of thing, albeit with lots of individual differences-- so distinguishing them all with lots of names invites madness.

Once upon a time, quasar was "quasi-stellar radio source," where as QSO implied optical. Both had optical counterparts, but one was discovered in the radio and one was discovered in the optical. But, the relevance of the different predates (even) me being in grad school....


mollishka said...

anonymous: That's hilarious! I remember, right around when I graduated, seeing some freshman wrestling with the same isothermal sphere problem I'd been made to do two years earlier. It's good to know my name lives on, though :)

Rob: what amuses most me about "quasi-stellar object" in this context is that, aside from a brief historical and quickly dismissed discussion of whether or not the Lyman-α forest is of cosmological origin, in this review "QSO" effectively means "bright point source really far away." Just because 10 years ago that meant AGN doesn't mean that nowadays the same techniques and discussion doesn't also apply to GRBs. Well, okay, and it also amuses me to see a fairly recent discussion of something that uses vocabulary that has gone out of favor so quickly.