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Q: How should we build complex forms, such as living things?
A: Organise them as a hierarchy of stable subassemblies, or homologous organs.
Q: Surely the genes are all you need to explain living organisation?
A: But the same organ can be the result of different genes! When we look at the genes as more than simply stretches of nucleic acid, but see them switching each other on and off, then a hierarchical organisation emerges spontaneously.
Q: Anyway, hadn’t Darwin explained homology?
A: No, his explanation fails, and the pre-Darwinian understanding of homology is much closer to the hierarchical approach.
Q: Isn’t there a quantitative approach that explains form?
A: No, form is a qualitative distinction between an inside and an outside. Living things are autonomous forms, themselves maintaining this boundary.
Q: Is such a boundary a purely material skin?
A: A boundary can be seen as the interface between the parts inside and the rest of the universe outside, through which information flows.
Q: Can’t an organism be described in isolation?
A: But then it would be a stone! An organism is a process of interaction with its environment, a process of creating and discovering.
Q: Creating and discovering? Is that a linguistic process?
A: Yes, a living thing is a focus of a linguistic process, where meanings are recognised and transformed.
Q: Eventually we will be able to reduce form to physics and chemistry, won’t we?
A: Could you reduce the meaning of these words to the chemistry of the ink? The same form may be realised in many different physicochemical configurations. The Cartesian method just won’t work.
Q: Do you mean to say that genetic and morphological descriptions of living things are radically different?
A: Yes, they are complementary yet incompatible. Continuity of morphological information is a kind of memory without mechanical storage. Without this holistic memory, the mechanically stored genetic information would deteriorate over time.
Q: I know that many quantitative models of morphogenesis have been proposed. So how can you say that form is qualitative?
A: Morphogenetic models exhibit bifurcation points, where the system shifts suddenly from one form to a quite different form.
Q: I feel uncomfortable with this idea of sudden jumps.
A: You feel happy about the sudden jumps in quantum physics, don’t you?
Q: But how do you decide between all the different interpretations?
A: Things become a lot clearer once you understand that the most important thing is the form of the quantum system, not the energy.
Q: Isn’t that a very organic way of putting things?
A: Yes, the ageing of a living system is much closer to the development of a quantum process than to anything Newton described.
Q: But how deep could the comparison be?
A: Well, certain forms of the equations for both look very similar, the same equations that describe a hologram. You can talk about a quantum process as a hierarchy of surfaces through which information flows.
Q: ‘Surfaces through which information flows’—that’s how you described living things and their organs, isn’t it?
A: Yes, that’s right! And these surfaces turn out to be holographic.
Q: Oh so that’s where the holographic principle in your title comes from?
A: Yes, the holographic principle may hold the key to bringing quantum physics together with relativity. Looks like it might bring in life and non-linear systems too!
摘自斯蒂芬*邬德(2005)的《生物演化和量子物理学中的全息原理》。
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