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COMPLEX TIME: Adaptation, Aging, & Arrow of Time

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A Stab at Time/Time: history of thinking about time, CPT time, matter and anti-matter, mirroring

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September 16, 2019
1:30 pm - 3:00 pm


John Harte (UC Berkeley/SFI)


John’s presentation at the “stab at time” workshop began with a review of the history of concepts of time.  Shifting perspectives, from the Greek philosophers, to Newton and Leibniz’s mechanics, to Clausius and Boltzmann’s thermodynamics, to Einstein’s relativity, to high energy physics and modern cosmology, were described.   The nature of the fundamental symmetries of nature, as reflected in the CPT theorem, were discussed, along with the observed breakdown of P (mirror symmetry) and T (time reversal symmetry) in weak interactions.  While the history of physics is generally characterized by the trend toward discovery of the underlying simplicity on the other side of complexity, and of the unity across seemingly distinct domains, the concept of time has arguably resisted this trend.  The more we look at time, the more complex it gets.

The probabilistic underpinning of the thermodynamic arrow of time, and the complete compatibility of the second law with the existence of life were discussed, along with speculations and deep puzzles about the connection between microscopic blurring and the awareness of time.  The presentation ended with a brief discussion of cultural time, the notion of “time binding” as passage onward to new generations of insights from previous generations, and the inadequacy of this process in the anthropocene where modern global-scale threats to civilization lack historical precedents. John concluded that time is not on humanity’s side.   

Presentation file(s)
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Post-meeting Reflection

John Harte (UC Berkeley/SFI) Link to the source page

Highlight: As a scientist, for me the highlight was learning a huge amount about how composers, dancers and choreographers think about the concept of time, and incorporate it into their work. Also fascinating was the realization that the medium within which an artist works places strong limits on how time is handled (to use an overly mundane word for a far from mundane process), and yet, as often occurs in the sciences, those constraints or limits can enhance creativity.

Open Question: Aside from the many open questions about time in physics and biology, the open questions that stood out for me revolved around how artists working across multiple domains (e.g., conducting and dancing) can best deal with incongruities in timing.

How has perspective changed: I began with no perspective on the arts, so rather than it changing, it originated and enlarged!

Impact on my work: Honestly, probably none. But that wasn't the point of the working group.

Echoes of the discussion: reminded me that artistic creation has similarities to creativity in the sciences (see comment on constraints above) but there are important differences that I had been unaware of. Out of our discussions the first day, a wonderful outline of the structure and content of a ballet on the theme of time emerged, mostly in one creative and intense blossoming from Karole at the end of the first day. Her design (blueprint) will be improved upon with iteration, but the core is there. I have never participated in a purely scientific working group, or lab group meeting with my students and postdocs, in which something similar happened. The usual timeline of creativity in the sciences, even by those with the most experience, is far slower, more halting, following a pathway with far more dead ends.

Reference Material