Parallel universes

Who would've guessed that the topic of parallel universes would come up at a dinner party, but that's exactly what happened to me last weekend.

The occasion was a small dinner party hosted by former UC President Mark Yudof to honor Gordon and Betty Moore, recipients of the UC President's Medal. After dinner, UC Davis Chancellor Linda Katehi asked me to explain parallel universes.

Not your typical after-dinner topic, but it was fun, because it is a little mind blowing. With the expansion of the universe accelerating, our portion of the universe may be as far as we'll ever see. So you can think of our observable universe as a bubble with a radius of just under 14 billion light years. And because there are a finite number of states of matter in such a bubble, if you go out far enough, you'll be able to identify an identical bubble, where the same people would be having the same dinner and the same conversation around the same table. We can even calculate that to encounter an identical bubble, you’d have to go out a distance of – brace yourself – 10 to the power of 10 to the power of 118 light years, a distance so large that it doesn’t matter whether it is in light years or millimeters. Amazing as it sounds, this could well be true. The second theory, eternal inflation, is more speculative. It posits that the universe is and has been expanding forever, with quantum effects causing big bangs to pop off randomly at different times and locations—and our universe is just one big bang that popped off.

I decided to spare everyone the quantum physics so stopped after just two of the four theories. All in all, it was a fun evening—and it was great to honor the Moores, who have been tremendous supporters of the University of California. I've only seen Gordon once since UCSC presented the Moores with the Foundation Medal two years ago, and I am delighted that both seem to be doing well.

Speaking of doing well, kudos to UC President Janet Napolitano. At last week's Regents meeting, and during a dinner with UC chancellors last Tuesday, she was bold, engaged, energetic, and inquisitive. I share her concern about tuition hikes and appreciate her willingness to consider new ideas, including the "cohort" model that would guarantee stable tuition levels for students throughout their UC years. Napolitano is bringing good ideas and solid communication skills to the table; the university is going to benefit.

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