I attended a very interesting lecture by Fr. George Coyne, Director Emeritus of The Vatican Observatory, entitled The Fertile Universe. While I was listening and watching, I wrote, as is my wont, a joke.
“ He showed a beautiful slide on the screen of the Universe taken by the Hubble Space Telescope. As I stared at it, I saw a very interesting and heretofore unreported anisotropy in the distribution of galaxies. I whipped out my Blackberry and started texting my bulletin to the International Astronomical Union when I realized that it was just because I was sitting way off to the side.”
As my dear and wise friend Dr. V.V. Raman observed, there is truth beneath that quip.
I think that's why I love optical, sound, and word illusions so much. They’re so humbling. Whenever a learned lecturer waxes emphatic, there is this innate cynicism that boils up within me which threatens to spoil the illusion. I love reading about all the cosmological conjurings of dark matter and energy, star life-cycles, distribution of galaxies in the Universe and am astonished at how far we can get based on just a few assumptions. If these assumptions are not correct, everything unravels. Hubble's law is one example. The farther away an object is, the faster it is moving with respect to us, and hence further Doppler-shifted (changed in color) are the familiar spectral lines of familiar elements. If they’re moving away, it’s called a red shift, as the colors appear redder than if there was no relative motion. Conversely, we can determine the distance to an object by measuring this shift with the simplest of spectrometers. Did you know that early on we didn't know whether quasars were very near or very far? I mean that’s a pretty big uncertainty! Very far in Astronomy is really really far. Like 10 Billion lightyears or 5,8000,000,000,000,000,000,000 miles (I think that’s like a bazillion). They had huge Doppler shifts indicating a great distance, yet still appeared so bright as to outshine entire galaxies. How can they appear so bright and be so far away? Maybe Hubble’s Law must be suspended in their case. They’ve found a loophole. Maybe they’re really close but are moving at immense speeds, disproportionate to our previous notion of the relation between relative velocity and distance. Or maybe the red shift is due to a completely different phenomenon and has nothing to do with relative motion and therefore nothing to do with distance. Or maybe Hubble’s Law needs either major renovation or the ‘ole Heave Ho! So, are they really really close and that’s why they’re so bright, or are they really really bright and really really very far away as indicated by their spectral shift? There are so many assumptions that need to be made to choose which is true. All we can do is take a poll amongst the various theories and see which explains the most, not all, mind you, but just the most. These days, we choose the latter- They’re very very far away and very very bright. But who knows. Maybe that will change some day. Our ideas about the Universe are so tenuous. Terms like Quasar (quasi-stellar), dark matter, all keep us honest by reminding us of how uncomfortable we are with our ideas and how willing we are to change our views as new data is gathered. This characterizes the Scientific Method more than the equations themselves.
Scientists often seem to jump to conclusions. In reality, we 'jump' because it's far better than to stagnate with skepticism and never know where our line of reasoning will lead.
Isn’t thinking wonderful!?