May 11, 2013

Lee Smolin says time is real

Seattle is a city full of geeks, it seems, and a bunch of us piled into the dark basement of Town Hall Seattle on a beautiful spring evening Tuesday to hear three talks about quantum mechanics, neutrinos, and the nature of time.

Dr. Lee Smolin was the headliner of the evening. Smolin has kicked up quite a ruckus with his new book, Time Reborn: From the Crisis in Physics to the Future of the Universe. In it, Smolin takes issue with a core notion of modern physics.

“We experience the world in time, we think in time, we act in time; this is so central to our conception of being human,” Smolin said. “But the scientific world view teaches that time is an illusion.”

Smolin added that, in his view, that claim is based on several incorrect arguments.
“Einstein and others who took that point of view are wrong for scientific reasons, and I try to make the scientific case for bringing back time to the center of our thinking and the center of our conception of nature,” he said.

Smolin rejects the notion that a mathematical description of the universe outside of time is the true reality, and that is the “crisis” of the book’s subtitle.

“If the experience of time is not central to reality, then neither are any human hopes and aspirations and the qualities that we so admire like decisiveness and imagination,” he said.

Smolin acknowledged that his arguments live somewhere in between physics and philosophy.

“I think that it’s essential to have the benefit of the history of thought when you’re tackling the deepest and hardest questions that we face, and the nature of time is one of them,” he contended.
The notion that time is an illusion has had its uses over the years, Smolin suggested, but added that the main fallacy of the approach has been what he called “physics in a box”, a method for studying small parts of the universe and then trying to extrapolate universal truths from that study. But he noted that you can’t put the whole universe into a box, and that the observers and the measuring systems in the experiments are typically outside of the box. And he said that even the laws of physics must be evolving, or if they aren’t, then they aren’t science.

“If the laws are truly outside of time then they’re inexplicable to any method that is checkable by science, because science requires experimentation and we can only experiment on things that can be modified,” Smolin said. “So if the laws are outside of time we just have to become mystics.”

The nature of time is a challenging topic for an hour-long talk, and Smolin had to punt a few times, noting that several concepts were topics for another hour, and that much more in-depth discussion could be found in the book.

We’re intrigued enough to grab a copy. You can get yours here.

Two talks by University of Washington graduate students preceded Smolin’s presentation. The talks were part of the UW’s Engage: The Science Speaker Series.

Ironically, Alan Jamison’s talk was definitely physics in the box. He gave an engaging presentation, titled “Cooling Atoms With Blinding Hot Light,” about his lab work to look at the behavior of ytterbium atoms, an element he joked “sits in a dark corner of the periodic table.”

“The first step in cooling atoms,” Jamison said, “is to heat them up.” As they vibrate intensely in the heat, individual atoms break off. Then they cool them down by shining lights on them; ytterbium has a resonance with certain green and purple wavelengths, and they can eventually slow the motion of the atoms down enough to get photos of clusters of them and study their behavior.

More on Jamison’s work at the Ultracold Atoms Group at the UW.

Jared Kofron followed with a talk about “A Massive Problem: A Brief History of the Tiny Neutrino.”
Kofron noted that the neutrino is the smallest particle we know of. “It’s a very strange, mysterious particle that has taught us a lot about the universe.” His talk was an accessible history of the neutrino.
The particle was dreamed up in the 1930s as a way to explain why energy seemed to be vanishing with beta decay. This created something of a panic, and German physicist Wolfgang Pauli proposed the neutrino as “a desperate remedy to save physics.” The notion of a particle that was incredibly penetrating, basically massless, and never observable was not too popular among scientists at first. But it fixed everything.

“Experiments made sense when viewed in the context of the neutrino,” Kofron said. “If you added the possibility that this little guy was carrying off all of the missing energy, all of a sudden the books balanced. From an experimental point of view, this was a real coup, this was a beautiful addition to the theory.”

More about Kofron’s work at the Center for Experimental Nuclear Physics and Astrophysics at UW.

Other books by Lee Smolin:


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