294 | Addy Pross on Dynamics, Stability, and Life

2024/10/28

Sean Carroll's Mindscape: Science, Society, Philosophy, Culture, Arts, and Ideas

Addy Pross

Sean Carroll

Sean Carroll: 物理学中，稳定结构通常指处于最小自由能状态的系统，例如滚到山谷底部的球。这种理解稳定性的方式不适用于生命体，因为生命体内部动态活跃，并非处于最小自由能状态。生命体不断更新自身的组成物质，维持自身模式。Addy Pross 提出了“动态动力学稳定性”（DKS）的概念来解释生命的稳定性。DKS 系统通过不断从外界获取资源来维持稳定状态，而非依靠机械或热力学稳定性。 Addy Pross: 生命是处于动态动力学状态的复制化学系统。稳定性有两种含义：低能量和持久性，两者并不总是重合。系统可以在能量上不稳定，但在时间上稳定（持久）。生命在时间上是稳定的（持久），尽管其能量上不稳定。喷泉是动态动力学稳定性的一个物理学比喻。化学家发现了化学喷泉，即能量上不稳定但时间上稳定的物质系统。

Deep Dive

Key Insights

What is the definition of life?

Life is a replicating chemical system in a dynamic kinetic state, a recently discovered state of matter.

Why are living organisms stable yet dynamic?

Living organisms achieve stability through dynamic kinetic stability (DKS), a state where systems are energetically unstable but persist over time due to constant turnover of their components, similar to a water fountain.

What fuels dynamic kinetic stability (DKS)?

DKS requires a constant source of energy, typically chemical energy, and a continuous supply of materials to maintain the system's dynamic turnover.

How does dynamic kinetic stability (DKS) relate to the origin of life?

DKS overcomes the limitations of "metabolism-first" theories by allowing for organization in the presence of an energy source. A key challenge is creating a DKS system that is also replicative, enabling evolution toward greater complexity.

Why is the RNA world hypothesis insufficient to explain the origin of life?

While RNA can replicate and evolve, it tends to evolve toward simplicity (shorter chains) rather than the complexity observed in life. This is because shorter RNA molecules replicate faster.

Why are bacteria still around if life evolves towards complexity?

Bacteria, though individually simple, exist within complex networks. Life's complexity lies in the interconnectedness of these networks, which continue to evolve and expand.

Why is DNA overrated in the traditional view of biology?

The genome-centric view of biology, where DNA controls the cell, is incomplete. Evidence suggests the cell controls the genome, using and modifying it as needed. The cell is holistically self-replicating, with DNA being one important part of a larger cycle.

How does dynamic kinetic stability (DKS) explain the emergence of cognition and consciousness?

DKS systems are inherently cognitive, possessing an awareness of their environment to acquire resources and survive. Self-awareness emerges as a consequence of this external awareness, as internal monitoring is crucial for responding to environmental changes. Consciousness and cognition are therefore present in rudimentary forms from the beginning of the evolutionary process and develop further over time.

Does evolution have a direction?

Evolution is directed towards increasing persistence, driven by a tendency for more persistent systems to outcompete less persistent ones. However, unlike the convergent space of thermodynamics, the space of DKS is divergent, leading to contingent pathways towards greater complexity.

Shownotes Transcript

Erwin Schrödinger said that the important characteristic of life is that it "goes on doing something... for a much longer period than we would expect an inanimate piece of matter to keep going under similar circumstances." Living organisms are in constant motion inside; so where does this stability and persistence come from? Addy Pross points to a novel kind of chemical phenomenon -- "dynamic kinetic stability" (DKS), a feature that enables a chemical "fountain" to persist in the presence of an energy source. This suggests an interesting perspective on the question of life's origin, and perhaps on the origin of consciousness.

Support Mindscape on Patreon).

Blog post with transcript: https://www.preposterousuniverse.com/podcast/2024/10/28/294-addy-pross-on-dynamics-stability-and-life/)

Addy Pross received his Ph.D. in chemistry from the University of Sydney. He is currently Professor Emeritus of Chemistry at Ben-Gurion University. He has held visiting positions in the University of Lund, Stanford University, Rutgers University, University of California at Irvine, University of Padova, the Australian National University Canberra, and the University of Sydney. He is the author of What Is Life? How Chemistry Becomes Biology).

See Privacy Policy at https://art19.com/privacy) and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info).

294 | Addy Pross on Dynamics, Stability, and Life 01:11:33 Share