May 12, 2010

It's going to be June by the time I get to prom

but who cares?

Onto the next page of SHP! In the left margin is scribbled, in Teaish, the lyrics to the chorus of Mr. Brightside, because it is still stuck in my head.

According to Newtonian physics, we would have a static universe, because everything would just staying in its prescribed gravitational orbits and nothing would change. By relativity, the universe should have been expanding and contracting, but the currently accepted belief was a static universe, so Einstein added a fudge factor, the cosmological constant, to make the shifting size go away.

However, Einstein (or Ein-schtein, as my teacher calls him) will have the last laugh. Please note the foreshadowing.

Tralala, moving along. Hubble telescope (20 year anniversary whoooo) results showed that distant objects have more red shift because they are moving away. Conveniently, I had learned this in physics three days prior to class, so I was able to twiddle my thumbs and fidget for an interval of time considerably longer than Planck's. Anyways, redshift means that objects are moving away, because their wavelength is increased. Apparently more distant objects are more red, or that is what I have in my notes, but one would think that it is actually ones that are moving away at a faster rate.

Then our teacher said, "Surprisingly, with some notable exceptions, all stellar objects were redshifted. This meant that-"

At least half the class put a hand up to ask about these exceptions, so he expanded. Some local galaxies, including that one that is on a crash course to slam into us a few billion years after the sun goes nuclear (that way of saying "blows up" works better when not talking about a natural nuclear generator), are moving towards us, and these are blue-shifted.

Then we have a couple of equations. I'm going to ignore those. Using the redshift data from Hubble, a graph can be generated demonstrating that the velocity with which objects are moving away is directly proportional to distance. However, it was graphed as a line on a logarithmic scale, so I think there was some sort of issue, but we can ignore that for the time being. So, Hubble shows that the universe is expanding from Earth, but Copernicus's Law is that it is never all about us (stop being so gosh-darned self-centered), so ALL points in the universe are moving away from each other.

Then I took a bathroom break, because I couldn't sit still and was being fidgety, so that is all for today.

1 comments:

Ginny said...

You can apparently modify graphs that appear curved by changing either the x-axis or both into lnx (and lny) to make a linear graph, because you can only have linear regression to conduct t-tests on.

But I'm sure that's not directly proportional, and so I shall stay confused.