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  • What is your definition ofcomplex systems”?

    您如何定義“複雜系統”?

  • So my one sentence definition is

    我用一句話來定義

  • systems that don't yield to

    某系統不會被迫於

  • compact forms of representation

    集中的表達

  • or description, and I should explain that.

    或描述形式,我應該解釋這個。

  • In the systems that physicists study,

    通常物理學家們研究的系統,

  • you can often write down on one page

    你可以在一頁紙上寫下

  • a few very beautiful, elegant equations, like Newton's

    一些非常完美的公式,例如牛頓的

  • laws for the conservation of momentum, or the Maxwell field

    動量守恆定律,或者是麥克斯韋場

  • equations for electromagnetism, and so forth.

    電磁方程式,等等。

  • And you can explain a huge amount of empirical data

    你可以去解釋很多的經驗資料。

  • when it comes to the genome, or the brain, or properties

    但是當描述基因組,大腦或者是

  • of society or literary history, as far as we know,

    社會特性,文明史這些問題,正如我們所知道的那樣

  • there are no such beautiful, elegant, compact descriptions.

    並沒有完善的經驗法則和系統的表述

  • And that, for me, is evidence

    對於我來說, 這就顯示

  • that we're dealing with a complex system.

    我們正在處理一個複雜系統。

  • Now, why is that? So, the reason why I think it's difficult

    為什麼呢?我認為之所以很難做到

  • to do is because those are systems that encode long histories.

    是因為這些系統包含了很長的歷史。

  • One of the characteristics, for me,

    我認為,複雜系統的某一項特徵,

  • of a complex system, is that it has found a means,

    便在於它作為一種方式,

  • or a mechanism, for extracting from its environment

    一個機制,來從其環境中

  • some information, in order to use it to behave

    汲取資訊,一邊用來做適應性行為

  • adaptively. To predict and control.

    為了預測和管控。

  • And consequently, it needs to be described using models

    結果呢,這就需要用模型來描述

  • that have a slightly different flavor to the ones that

    尤其是那些稍稍不同於

  • we have been traditionally familiar with in the mathematical natural sciences.

    我們在數理自然科學傳統研究中所熟悉的那樣。

  • And typically, those models will be computation.

    通常來說,這些模型需要通過計算。

  • So, I'm going to ask you

    我想請問您

  • the same question that I'm asking everybody, which is

    一個我用來問每一個人的同樣的問題,你對於

  • what is your definition of a complex system. Oh no!

    複雜系統是怎樣定義的?哦,

  • That's what everybody says.

    每個人都這樣說。

  • In theoretical computer science, we don't say that

    在理論電腦科學中,我們通常不會說

  • systems are complex or simple, per se,

    系統本身有複雜和簡單之分。

  • we more typically say that questions are

    我們通常會說某些問題是

  • complex if those questions require a lot of computational

    複雜的如果這些問需要很多計算

  • resources to solve. A lot of time, a lot of memory,

    來解決,佔用很多時間,很多記憶體

  • a lot of communication between people.

    並且需要很多的與人的交流。

  • Some limited resource.

    而資源卻是有限的。

  • Different questions might have different levels of computational complexity. So for instance,

    不同的問題會有不同程度的計算複雜度,例如

  • if what you want to know is what will the system

    如果你想知道的是系統

  • look like t time steps from now,

    在一段時間 t 之後會看起來如何

  • you can answer that question with about t time

    那麼你可以在模擬 t 時間後來回答

  • by simulating it forward, but an interesting

    但是一個有意思的問題在於,

  • question might be, well, maybe there is no algorithm that works much

    也許並沒有某種計算方法可以

  • faster than that. Maybe there's no way to leapfrog over

    算的如此快。也許我們並沒有辦法可以超越

  • the history. Maybe like a chaotic dynamical system that

    歷史發展的過程。 例如一個混亂的動態系統

  • has no closed-form solution, maybe there is no shortcut to doing

    其並沒有閉合形式的解,或許並沒有捷徑來

  • that laborious step-by-step simulation.

    做冗長的每一步的模擬。

  • So, for me, I find it helpful to, rather than

    所以,對我來說,我覺得是有幫助的,而不是

  • saying, is this system simple or complex? I mean, I don't deny

    他說,這是系統簡單或複雜?我的意思是,我不否認

  • that we often have clear ideas about that, but I find it helpful

    我們經常有關於明確的想法,但我發現它有用

  • to change the question a little bit to, give me

    改變的問題一點點,給我

  • a yes or a no question you want to answer about this sytem,

    回答這個系統是或否,

  • or a quantity you want to compute about this system, and then let's talk

    或者你要計算這個系統,然後量讓我們來談談

  • about how hard it is computationally to answer that question

    有關它用計算來回答這個問題是多困難,

  • or compute that quantity.

    或計算的數量。

  • Well, it's a complicated

    嗯,這是一個複雜的

  • concept. I didn't say complex, just kind of

    概念。我並沒有說只是複雜的

  • complicated.

    种类。

  • So, this actually ties in with a discussion I'm sure we'll

    所以,這實際上關係在一個討論中,我敢肯定,我們會

  • have on information, so I have a rather precise notion

    對資訊,所以我有一個相當準確的概念

  • of what I mean when I refer to a natural or artificial

    我的意思是指自然或人工

  • system as complex, and what I mean in particular is that it has a very sophisticated

    系統複雜,我的意思,特別是它有一個非常複雜的

  • internal causal architecture that stores and processes information.

    內部架構来存儲和處理的資訊。

  • So, the technical things that we'll talk about shortly have to do

    因此,在技術方面的東西,我們將討論在短期內要做的

  • with how we measure stored information and the amount of structure.

    與我們如何測量所存儲的資訊和結構的量。

  • So, information in many ways stands in for trying to describe

    所以,在很多方面的資訊代表了在試圖描述

  • how complex a complex system is, and various

    多麼複雜的一個複雜的系統,以及各種

  • kinds of information processing and storage can be associated with how a system is organized.

    種資訊處理和存儲能以怎樣的系統的組織相關聯。

  • So it's a key concept, certainly

    所以這是一個關鍵的概念,當然

  • Shannon's original notion of information as degree of surprise,

    香農的原始資料,驚喜度的概念,

  • degree of unpredictability in a system, or how random a system is

    不可預測的系統的程度,或如何隨機系統是

  • needs to be augmented. So that's certainly the focus of a lot

    需要被增強。所以這肯定是一個很大的关注

  • of my work is trying to delineate that there are many different kinds of information,

    是我試圖描繪許多不同種類的資訊,

  • not just Shannonian information.

    不只是香農信息。

  • So, my definition of complex systems

    所以我定義複雜系統的

  • is a system that has

    是一個系統,有

  • interactions. It has nonlinear elements in it.

    互動。它有在它的非線性元素。

  • I tend to work on high dimensional systems not low dimensional systems.

    我傾向于工作在高維系統不低維系統。

  • And I like to use the methods of statistical mechanics

    我喜歡用統計力學的方法

  • from physics to understand problems in these systems.

    從物理學理解在這些系統中的問題。

  • Most of the time, the interesting features in these systems have

    大多數時候,在這些系統中,有趣的特性有

  • scaling properties, that is to say they have power laws

    尺度屬性,也就是說,他們有幂率法则

  • or fractal objects in them, embedded in them someplace,

    或者是分形物體,嵌在其中的某個地方,

  • either in the actual physical arrangement of them

    無論是在他們的實際物理排列

  • or in terms of the statistics that you see.

    或者,你看到的統計資料計算。

  • So my basic definition is that a complex system consists of a bunch of entities

    所以我的基本定義是一組實體的複雜系統由

  • that may not start out diverse, but end up being diverse. They are connected

    這可能開始不是多樣的,但最終會是多樣的。它們被連接

  • in some way, usually through some sort of network structure or some spatial

    以某種方式,通常是通過某種網路結構或某些空間的

  • structure, and they get information and signals through that network

    結構,他們通过網路或局部結構获得資訊和信號

  • or local structure, but they also sometimes get some global signals or global information,

    但他們有時也得到一些全球性的信號或全球資訊,

  • which could be prices in a market, or temperature in a system, so that

    這可能是價格在市場或溫度在一个系統中,從而使

  • in addition to be sort of diverse and interconnected, they are also interdependent, so the

    除了是那種多樣化和相互關聯的,他們也是相互依存的,

  • actions of one agent in the system will sort of

    所以 一個智能體動作在系統中的影響的排序

  • influence or have implications for another agent. So in the context

    或有其它智能體的影響。因此在一個社會系統,

  • of a social system, like in economics, I'll say that if I go in and buy bread in the grocery store

    如在經濟學方面,如果我進去雜貨店買麵包

  • whether I buy whole wheat bread or white bread, you really don't

    我是否買全麥麵包或白麵包,你真的不關心。

  • care. It's not interdependent. There's no real strong interdependence, other than to

    這不是相互依賴的。沒有比價格更強的

  • the prices. But if I decide to drive my car on the road

    相互依存關係。但是,如果我決定要開我的車在路上

  • or drive my car really fast down the road, those sort of things, then that actually can affect you

    還是開我的車在路上非常快,那些之類的東西,那麼這實際會很大程度上

  • in a big way. So they're interdependent. And the last thing

    影響到你 。所以,他們是相互依存的。和過去的事情

  • is in addition to having these

    是除了具有這些

  • interdependent behaviors and networks and diverse agents, that the agents adapt

    相互独立行為和多樣網路,agent適應

  • and respond to the environment which that they're in. So it's not just a case of them following

    並回應環境,所以這不只是下面的情況

  • simple rules, but that they sort of adapt. Now this last part

    簡單的規則,但那種適應。現在,這最後一部分

  • gets a little bit tricky philosophically, because adaptation is really just a higher-order

    變得有點棘手的哲學,因為適應性是真的只是一個高階

  • rule, so you can have a first-level rule and then a meta rule

    規則,所以你可以有第一級規則,然後一個元規則

  • and so, you could say that they are rule based, but they are sort of meta rule based,

    所以,你可以說他們是基於規則的,但他們是那種基於元規則,

  • that they allow for behavior that

    他們允許的行為

  • can respond to the signals that they are getting both globally and locally. Now the last thing

    可以回應他們獲得在全球和地方的信號。現在過去的事情

  • will mention is another sort of paradox in the definition of complex adaptive systems

    會提到是複雜適應系統的定義另一種悖論

  • is that a system like that can be complex, but it need not be.

    就是這樣的系統可以是複雜的,但它不一定是。

  • So a system can have those components to it, but it can end up producing

    這樣的系統可以具有這些部件构成,但它可以最終產

  • an equilibrium. Especially if I look at an economic system

    一個平衡。尤其是當我看到一個經濟體系

  • some parts of economic systems really equilibriate quite well, but then others

    經濟體系的某些部分確實平衡的很好,但隨後其

  • end up being really complex. So if you look at oil consumption

    最終非常複雜。所以,如果你看一下隨著

  • over time at the global level, that's pretty predictable, it's a pretty stable pattern

    時間的推移在全球範圍內的油耗量,這是相當可預測的,這是一個非常穩定的模式

  • but if I look at oil prices over time, that's complex, because

    但如果我看到油價隨著時間的推移,這是複雜的,因為

  • there's much more interdependencies and all those things come into play.

    還有更多的相互依存關係,所有這些東西在起作用。

  • So John Holland and I sometimes joke that we should call them systems capable of producing

    因此約翰荷蘭和我有時候開玩笑說,我們應該稱他們為能生產系統 複雜性。

  • complexity. That doesn't sound as remarkable.

    這聽起來並不為顯著。

  • Okay, well, that is a question that people have debated a lot.

    好了,好了,這是一個問題,人們已經討論了很多。

  • I guess

    我猜

  • most people would agree that a complex system is a system of many interacting parts

    大多數人都會同意,一個複雜的系統是許多局部系統的相互作用,

  • where the

    相互作用的系統

  • system is more than just the sum of its parts.

    不仅仅是其各個部分簡單相加。

  • It shows emergent behaviors which are not just the sum of the individual behaviors

    它显示了突發行為而不是個人行為的簡單相加

  • of the parts. Other people add

    的部分。其他人加入

  • extra elements to that, but that's probably what my definition is

    額外的元素,這可能就是我的定義是

  • pretty much. It's a system of interacting parts which shows emergent behaviors.

    相当好。系統相互作用的部分顯示出了涌现的的行為。

  • Okay, that's pretty simple. Sort of unpacking that

    這很簡單的。排序

  • takes a little more time.

    需要多一點的時間。

  • So I'm going to give you a definition of complex systems, but

    因此我給你複雜系統的定義,但

  • I will remind you that many important concepts

    我要提醒你很多重要概念

  • like virtue and life are very hard to define

    例如美德和人生是很難下定義的

  • and I think complex systems are somewhat in that category.

    我認為複雜系統也是這一類。

  • Nonetheless, the kinds of systems that I call complex

    儘管如此,該種系統稱之為複雜

  • have many interacting active components

    有許多相互作用的部分

  • and the interactions between the components have

    和部件之間的相互作用有

  • nontrivial or nonlinear interactions

    平凡的或非線性的相互作用

  • and that leads to the system having unpredictable behavior. You may have

    並導致系統其不可預知的行為。你可能有

  • heard those things before. But importantly,

    之前聽說過這些事情。但重要的是,

  • all of the components are either learning or

    所有的元件都要麼學習或

  • modifying their behavior in some way while the system

    以某種方式修改在

  • is behaving.

    系統中的表现。

  • And so that leads to all kinds of interesting dynamics.

    導致各種有趣的動態。

  • So that's roughly what I think of when I think

    所以這大概是我覺得當我想到

  • of a complex system. So do you think that adaptation is

    一個複雜的系統。你認為適應

  • essential for complex behavior?

    對於複雜的行為所必需的吗?

  • Well, it's essential for the kind of complex behavior that I'm most interested in

    嗯這是我最感興趣的是对各種複雜行為是必需的

  • Okay, fair enough.

    好,很公平。

  • I think my definition is probably like a lot of other people's

    我認為我的定義可能是像很多其他人的

  • definition in that a complex system is something

    在定義複雜系統是什麼,

  • with a lot of interacting parts where something

    有很多相互作用的部分的東西

  • about the way those parts behave when they interact is qualitatively different

    它們相互作用的部分行為方式是質的不同

  • than the way they behave if you look at them individually. So

    相比于你看他們的個體行為。

  • it's something with emergent phenomena. And I think we can then quibble

    這件一些涌现現象。我認為,那麼我們就可以狡辯

  • about what exactly all those words really mean

    關於究竟那些話的真正含義

  • so for example I might mean something a little bit different than some other people, but I

    所以我可能意味著与其他人有點不同,

  • don't think I have anything particularly unique in my definition.

    但我不覺得我有什麼在我的定義中特別獨特。

  • Complex systems tend to be things that

    複雜系統往往從簡單

  • are different from simpler, usually

    趋向于不同,通常

  • physical, systems in that they tend to be heterogenous, they tend to

    物理的該系統中,它們往往是趋向異質的

  • be made up of parts that are the not the same kind of parts. For example,

    可以由不同種部分构成的。

  • people and firms in a city are all different. They are not all the same.

    在一個城市的人與企業都是不同的。它們不是都一樣的。

  • They tend to be, many of them are open ended, although not all of them.

    很多往往是開放式的,雖然不是所有的人。

  • So a city or an ecosystem can keep on evolving

    因此一個城市或一個生態系統可以繼續進化

  • Often the thing that makes them hardest to study in terms of making predictions

    通常对最難的事情進行預測方面,研究

  • about them is that they also typically have chains of causation

    對他們來說,他們通常也有因果關係鏈

  • mechanisms that make things happen that are circular, so there are feedbacks

    讓事情發生有回路機制,因此是有回饋的

  • both positive and negative that make their evolution

    正反馈与负反馈都会使他們進化

  • at least more difficult to study than in simpler physical

    至少比研究更簡單的物理系統或工程系統 難比更困難

  • systems or engineered systems, where we can deal with them in regimes where they're simpler

    在這裏他們处理的很簡單

  • and linear, and they can respond in ways that we can at least hope to characterize.

    和線性的,且可以在一些方法來表徵回應。

  • So those things are still an operating definition of what a complex system

    所以這些東西仍然是定義什麼是複雜系統

  • might be. But they go a long way to say what a complex system typically

    通常典型的複雜系統

  • is, from ecosystems to organisms to cities to brains.

    就是從生態系統到組織到城市到腦。

  • A complex system is one

    一個複雜的系統是

  • that contains enormous numbers of actors or agents

    一個包含大量的智能體之間的

  • that are interacting in usually in a nonlinear kind of fashion

    交互, 通常有非線性各種類型

  • form which all kinds of

    的多層次

  • multi-level behavior evolves from

    行為的演變,

  • So there are these emergent phenomena, but also

    因此有這些突發現象,但是

  • I think a critical part of a complex system that distinguishes it

    我覺得複雜的系統關鍵部分

  • from what we might call a simple system, like the motion of the planets around the sun,

    是識別它來自什麼,也许我們可以稱之為一個簡單的系統,如圍行星繞太陽的的運動,

  • is that on the one hand, you can't

    是在一方面,你不能封裝

  • encapsulate the dynamics in just a few

    動力學幾個簡單

  • simple equations and that is intimately related

    的公式,這是密切相關的,

  • to the fact that these systems are evolving

    這些事實表示系統是進化的

  • and are adaptable. And I think that this is one of the most

    且適應性強。我認為,這是在與傳統系統間的

  • crucial differences between that and traditional systems that I

    最重要的區別之一,我職業生涯大部分

  • have dealt with in most of my career under the guise of physics.

    是在物理學的指導下。

  • Subtitles by the Amara.org community

What is your definition ofcomplex systems”?

您如何定義“複雜系統”?

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B1 中級 中文 美國腔 複雜 定義 行為 計算 作用 資訊

複雜度介紹。什麼是複雜系統? (Introduction to Complexity: What are Complex Systems?)

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    Josh 發佈於 2021 年 01 月 14 日
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