SERIES:
Meeting the Entropy Challenge




More videos in this series


Foundations of the Second Law
October 4, 2007
1:30 PM

LOCATION:
Broad Institute

ABOUT THE PANEL DISCUSSION:
The nine panelists set out to address, very briefly, some of the key questions of the symposium.

Seth Lloyd discusses the Maxwell demon paradox and the spin-echo effect, and how in some cases, in an apparent violation of the Second Law of Thermodynamics “entropy goes up and whoa, goes down then up.” He notes that when the laws of thermodynamics appear not to be true, “we simply revise our opinions and re-describe” them, which is “a pathetic situation.”

Owen Maroney invokes “straightforward statistical mechanical assumptions” in his discussion of whether “something can violate the Second Law or not,” and raises Szilard’s engine and Landauer’s erasure principle.

Silviu Guiasu aims to show there is no contradiction between microscopic reversibility of classical mechanics, as described by Hamilton’s equations of motion, and macroscopic irreversibility as described by the increase of entropy.

Ping Ao believes the dynamics behind Darwinian evolution “provide a natural framework” for thermodynamics, and it remains to translate “global statements to precise mathematical language.”

Jochen Gemmer discusses bubbles in Hilbert space, while examining how we might overcome the apparent contradiction between quantum dynamics and thermodynamics.

Bernard Guy focuses on the link between the Second Law and the problem of time, seeking clues for understanding the opposition of reversibility and irreversibility. He sees clashing constructs of time and space in the separate worlds of cognitivists and physicists.

Gian Paulo Berretta praises the seminal work and “pioneering intuition” of Keenan and Hatsopoulos, which inspires new answers to such fundamental issues as whether entropy is an intrinsic property of matter, and if irreversibility is an intrinsic feature of microscopic dynamics.

Speranta Gheorghiu-Svirschevski believes a nonlinear approach can help reconcile the Second Law and quantum evolution. In particular, she looks for ways to “reconcile locality and separability,” while acknowledging that general wisdom says it’s not exactly possible.

Dorion Sagan says that “ever since Darwin, life has been considered an exception to the Second Law.” On the contrary, “entropy, rather, energy spread, and evolution are inextricably linked.” Sagan suggests that “life may just be another energy spreading system,” and “death is the name we give the inevitable disruption of a specific part of life’s network.”

NOTES ON THE VIDEO (Time Index):
Video length is 1:30:44.

Robert Silbey opens the session and then moderates the panel presentations.

At 2:51, Seth Lloyd begins.

At 11:13, Owen Maroney begins.

At 18:41, Silviu Guiasu begins.

At 24:55, Ping Ao begins.

At 31:20, Jochen Gemmer begins.

At 36:13, Bernard Guy begins.

At 43:07 Gian-Paulo Berretta begins.

At 50:16, Speranta Gheorghiu-Svirschevski begins.

At 59:35, Dorion Sagan begins.

At 1:07:57, Silbey invites audience questions.