我叫保罗·戴维斯(Paul Davies)。我的职业是理论物理学家和宇宙学家。我是亚利桑那州立大学的校董教授(Regents Professor),同时也在那里担任科学基本概念“超越”中心(Beyond Center for Fundamental Concepts in Science)的主任。我已经写了30多本书。额,最新的一本是《什么在吞噬宇宙?以及其他宇宙问题》(What's Eating the Universe? and Other Cosmic Questions),在此之前是《机器中的恶魔》(The Demon in the Machine),整本书都是关于生命的本质。本次 Big Think 访谈由 Pangram 赞助呈现。在充斥着 AI 生成内容的互联网中浏览是一种令人沮丧的体验。将真实与虚假、人类与机器区分开来正变得越来越难。Pangram 是最值得信赖的 AI 检测器,并拥有严谨的公开研究支持。Pangram 可以告诉你,你所阅读的内容中有多少是由 AI 生成的。如果你觉得某张图片可能是 AI 制作的,Pangram 也能检测出来。若要重新对你所见所读的内容建立信任,请访问 www.pangram.com。现在回到访谈。
英文原文
My name is Paul Davies. I'm a theoreticalphysicist and cosmologist by profession.
I'm a region's professor at Arizona State
University where I'm also the director of
the Beyond Center for Fundamental Concepts
in Science. I've written over 30 books. Uh
the most recent is what's eating the universe and
other cosmic questions and before that the demon
in the machine which is all about the nature of
life. This Big Think interview is brought to you
by Pangram. Navigating an internet filled with
AI generated content is a [music] frustrating
experience. It is becoming harder to separate real
from fake and human from machine. Pangram is the
most trusted AI detector backed by rigorous
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And now back to the interview.
第一章:什么是生命?定义与信息
[叹气] 第一章,什么是生命?定义与信息。其实存在三个起源之谜。我常说,有宇宙的起源、生命的起源,以及意识的起源。额,现在回顾我职业生涯的大部分时间,我一直从事宇宙学研究,我想说我们对宇宙起源的了解其实相当深入。意识的起源则是一个极其棘手的问题,因为我们甚至不知道该如何提出问题。谈到意识的本质时,我们不知道该应用怎样恰当的概念结构。我认为它至今仍深具神秘色彩。生命的起源也是个难题,但我们多少已经在着手研究了,我可以想象在几十年内,我们可能会有相当好的理解。人们总是有可能陷入对字词和定义的纠缠之中。关于生命有一个非常著名的定义,它是借鉴了色情作品的定义:我看到它时我自然知道(I know it when I see it)。但如果你想要一个简明扼要的定义,目前相当流行的一个说法是:生命是化学加上信息。
英文原文
[sighs] Chapter one, what is life? Definitionand information. There are really three
origin mysteries. I like to say there's the
origin of the universe, the origin of life,
and the origin of consciousness. Uh now most of my
career I've been working in cosmology and I would
say that we actually understand the origin of the
universe pretty well. The origin of consciousness
is a really tough one because we don't even know
how to frame the questions. We don't know the
right conceptual structure uh to apply when it
comes to the nature of consciousness. I think
it's still deeply mysterious. The origin of life
is a tough one, but we're sort of on the case, and
I can imagine that within a few decades, we might
have a pretty good understanding. There's always
a danger of getting hung up on the words and and
the definitions. There's a very famous definition
of life which is based on the definition of
pornography. I know it when I see it. But if you
want a snappy definition, one that's quite popular
at the moment is that life is chemistry plus
information.
你看,生命并不是某种具有魔力的物质,也没有什么极其罕见的成分。如果你把一个人分解到分子结构,然后试图在公开市场上出售这些成分,构成我们人体的材料最多只能卖几美分。你看,我们的身体内部并没有什么非常特殊或罕见的东西。所以重要的不是构成我们的材料,不是硬件;真正关键的是我们的所作所为,我们的行为。这就进入了我们或许可以称之为软件的领域。所以我会这样表述:我会说是硬件和软件。这是平行的两套叙事,它们并不冲突。但我想说的是,直到最近,在试图理解生命起源时,软件层面实际上一直被相当程度地忽视了。但显然,要想完全理解生命,我们必须把这两者结合起来。我认为我们距离做到这一点还非常遥远。
英文原文
You know, it's not like life is somesort of magic matter or it's got some extremely
rare ingredients. If you take uh human being and
uh break them down to their molecular structure
and then try and sell the components on the open
market, you wouldn't get more than a few cents
uh for the stuff that we're made of. You know,
there's nothing very special or rare uh inside
our our bodies. So it's not what we're made of,
not the hardware. Uh it is really uh what we do,
our behavior. Uh and that's where in the realm
of uh what we might call software. So I would
express it this way. I'd say it's hardware and
software. These are parallel narratives. They're
not in conflict. But I would say that the software
aspect has really been rather neglected until
recently when it comes to trying to understand
the origin of life. But it's clear that to have a
full understanding of life. We have to integrate
those two. I think we are very far from having
done that.
生命本质与生机论的历史视角
当然,“什么是生命”这个问题并不新鲜。它不仅属于科学时代,在哲学史上更可以追溯到数千年前,因为生物确实格外引人注目,早期的希腊哲学家也觉得它们确实非同寻常。例如,亚里士多德曾思考如何将生物体与更广阔的万物秩序联系起来。在他的观点中,因果关系的本质使得人们不仅可以将类似生命的属性归于活的有机体本身,还可以归于整个宇宙。也就是说,当你丢下一块石头时,它会掉落在地上。那是为什么?不是像我们今天所认为的那样是因为引力,而是因为它在下方有一个“自然位置”。它试图到达它的自然位置。因此从这个意义上说,它具有目标导向性。
英文原文
And the question of what is life ofcourse is not a new one. It's not just part of the
scientific era. It goes back thousands of years
in the history of philosophy because living things
do stand out and they struck the early Greek
philosophers as being something really special.
For example, Aristotle had a thought about how to
connect living organisms with the wider scheme of
things. And his view uh the nature of causation
was such that one could really attribute lifelike
properties not just to living organisms themselves
but to the universe as a whole. Uh that is when
you drop a stone it falls to the ground. Why is
that? not as we would think today because of the
force of gravity uh but because it had a natural
place uh down there. it was trying to get to its
uh its natural place. And so in that sense it was
goal oriented.
而如果我们追溯到100或150年前,曾有这样一种观念:嗯,你知道,也许生命需要某种额外的力,或者用法语表达的“活力”(élan vital),或者某种赋予物质生命力的东西——你可能拥有复杂的物质,但你需要某种其他类型的精华注入其中并使其活过来,展现出奇妙的特性。这被称为生机论(vitalism)。多年来,它开始与物理学中的一些其他现象联系在一起,比如也许是电,或者放射性,你知道,或者某种我们尚未完全理解的神秘力量。嗯,我认为那些观点后来被相当彻底地推翻了。
英文原文
And if we go back 100 150 years,there was this notion that well, you know,
maybe uh uh life requires some additional
um force or uh lam vital as what it was expressed
in French or some some uh something to animate the
matter that you might have complex matter but
you need to sort of have some other uh type of
uh essence which would infuse it and would make
it come alive. um uh and do its amazing things.
And so that was known as vitalism and uh over the
years came to be associated with a number of other
things in physics like electricity perhaps or
maybe radioactivity you know or some mysterious
force that we didn't uh yet fully understand.
Um and and those ideas I think became pretty
thoroughly discredited.
现在来看,达尔文提出了一个绝妙的理论,解释了生命一旦在地球上启动之后是如何演化的,它如何在几十亿年间演化,呈现出我们今天所看到的复杂生物圈。但他不愿就生命最初是如何开始的表态。因此,在探讨什么是生命这个问题时,你不可避免地会遇到这样一个问题:非生命是如何变成生命的?你看,它在那个过程中获得的额外特殊特质究竟是什么?达尔文说过一句妙语:“此时谈论生命的起源纯属废话,倒不如去谈物质的起源。”但到了大约20世纪20年代,人们对我们或许可以称之为化学路径的研究兴趣日益增加。我认为生命基于化学是非常显而易见的。那么,究竟发生了怎样的化学魔法,才在最初阶段变幻出了生命?
英文原文
Now Darwin had a brillianttheory of how life evolves once it gets going on
planet earth, how it has evolved over billions of
years to give us the complexity of the biosphere
that we see today. But he wouldn't be drawn on how
life got started in the first place. So addressing
the question of what is life, you inevitably come
up against this question, well how does non-life
turn into life? You know, what is that extra
special thing it acquires on that pathway? Darwin
said it's a wonderful quote. It's mere rubbish at
this time talking of the origin of life. One might
as well talk about the origin of matter. But by
about the 1920s, uh there was increasing interest
in the what we might call the chemical pathway.
I think it's pretty obvious that life is based
on chemistry. So what sort of chemical magic
took place to conjure life into being in the
uh first stages?
从米勒实验到薛定谔的信息视角
人们曾在实验室里尝试“烹调”出生命。在20世纪50年代初,化学家哈罗德·尤里(Harold Urey)成功引起了一名年轻学生斯坦利·米勒(Stanley Miller)的兴趣,去尝试重现早期地球上的条件。他们并不真正清楚那些条件是什么,但他们猜测大气中会有某些气体、水、闪电等等。于是米勒做了这个早期的实验:他把几种气体放入一个烧瓶中,通电产生电火花持续了一周,并欣喜地发现,被称为氨基酸的蛋白质构成要素——这些简单的分子——在此过程中生成了。烧瓶底部还出现了一种类似棕色污泥的物质。因此,那看起来确实像是走在通往生命的道路上了。
英文原文
And there were attempts tocook up life in the lab. In the early 1950s,
the chemist Harold Yuri managed to interest a
young student Stanley Miller in attempting to
recreate the conditions on the early Earth. They
didn't really know what those conditions were,
but they had a guess that there would be certain
gases in the atmosphere and water and lightning
and and so on. And so Miller did this uh early
experiment in which he put a number of um gases
in a in a flask and sparked electricity through
it for a week and was gratified to find that the
building blocks of proteins called amino acids,
simple molecules, um were made in this process.
And there was sort of brown sludge in the bottom
of the flask. And so that really looked like
uh that was uh that was on the pathway to life.
但话又说回来,你看,这缺乏对生命的定义。它试图从化学成分的角度、而不是从生命所作所为的角度来定义生命。因此我想说,那是在解决生命的硬件问题,而不是软件问题。如果我们快进到今天,我认为这仍然是一个非常深刻的问题。如果你想把生命的定义仅仅聚焦在硬件上,仅仅聚焦在其化学成分上,那么我们确实取得了一点进展。但我可以说,相比最初的米勒实验,进展并不大。人们继续做了更多这类前生命实验,但他们在通往生命的道路上并没有走得很远。
英文原文
But again um you see this this lacked a definitionof life. It it was an attempt to define life in
terms of its chemical components not in terms
of what it does. So I would say that that was
addressing the problem of the hardware of life
but not the software. And if we fast forward to
today I think this is still a very deep problem.
If you want to focus a definition of life just
on the hardware, just on its chemical components,
uh well, we made a bit of progress. Um not much
I might say from that early Miller experiment. Um
there people have gone on to do more of these
prebiotic experiments, but they haven't got
very far down that pathway to life.
量子力学在1925年迎来辉煌开端后,短短几年内就解释了从亚原子粒子一直到恒星的物质本质;埃尔温·薛定谔(Erwin Schrödinger)作为量子力学的创始人之一,写了一本名为《什么是生命?》(What Is Life?)的书。薛定谔在书中提请人们注意一个事实:正如我之前所言,生命是化学加上信息,生命所蕴含的信息内容是其运作的关键。他也很清楚,为了维持该信息的稳定性,必须借助量子力学。他提出了一个相当优美的隐喻。他说,这种生物学信息必须存储在类似非周期性晶体(aperiodic crystal)的物质中。那是什么意思呢?嗯,晶体大家当然都很熟悉。它是一个非常简单的东西,具有非常稳定的结构。想想盐晶体,它只是原子在几何上重复排列的图案。这毫无疑问,除了它无法存储太多信息,因为它实在太简单了。因此,他需要一种既具备晶体稳定性、又不具备那种单一周期性,而是其组成部分可以拥有大量替代排列和置换的结构。所以他提出了非周期性晶体的概念。当时并不知道那种分子可能是什么,但后来正是克里克(Crick)和沃森(Watson)对 DNA 的著名分析宣布了它就是生命分子;现在我们会说它包含了生命之书,它在那种被称为 DNA 的非周期性晶体中编码了构建生物体所必需的信息。
英文原文
Now quantummechanics with its brilliant uh start in 1925 went
on within a very few years to explain the nature
of matter all the way from subatomic particles
up to stars and Irvin Schroinger he was one of
the founders of quantum mechanics wrote a book
called what is life and in his book Schroinger
drew attention to the fact that life is as I've
stated it earlier chemistry plus information that
the information content of life was key to how it
operates. He was also very clear that uh for
the stability of that information, one had to
use quantum mechanics. He came up with a metaphor
which is a rather beautiful one. He said that this
biological information uh would have to be stored
in something like an aeriodic crystal. What does
that mean? Well, a crystal is of course familiar
to everybody. It's a very simple thing. It's a
very stable structure. Think of a salt crystal.
It's just a geometrically repeating pattern of
atoms. no problem about that except that that
can't store very much information because it's
just too simple. So he wanted something that had
the stability of a crystal uh but would not just
have that simple periodicity but could have um
a vast number of alternative arrangements and
permutations of its components. So he had this
idea of an a periodic crystal. didn't know at the
time what that molecule might be but it took
Crick and Watson's famous analysis of DNA to
declare that that was the life molecule and now we
would say it's contains the book of life it codes
the information uh that is necessary to build the
organism in that a periodic crystal called DNA
信息理论与生命的软件层
我认为信息的概念对于理解生命与非生命的区分是绝对至关重要的。人们在日常生活中非常随意地使用“信息”这个词。而且我们毕竟还有信息技术。那么,到底什么是信息,为什么这个被称为“信息”的东西是生命的关键?信息的一个相当不错的通用定义是“不确定性的减少”。给你举个简单的例子。你抛一枚硬币,可能是正面朝上,也可能是反面朝上。你不知道是哪一种。但如果你去查看并确认结果,那种50/50的不确定性就减少了,你确信它是——比如说是正面——这意味着你获得了一点信息。我特意使用这个词,因为技术定义确实就是1比特(bit)。它是二进制数字(binary digit)的缩写。因此,通过查看抛出的硬币所获得的信息,就是将你的不确定性减少了1比特。你可以在此基础上进一步构建,这就是一种量化信息的方式。而且整整有一个科学和工程学分支——信息论——正是建立在那个相当严苛的定义之上。
英文原文
I think the concept of information is absolutelycritical to understanding the distinction between
uh life and non-life People use this term
information in a very informal way in daily
life. Uh and we have after all information
technology. Uh and so uh what is it and why
is it that this thing called information uh is
the key to life? A pretty good general definition
of information is reduction in uncertainty. Just
give you a simple example. You might flip a coin
and may come down heads, may come down tails.
You don't know which. But if you look and find
out that uncertainty 50/50 is reduced, you are
certain it's say heads and that means you've
acquired a bit of information. And I use that word
adverisedly because to the technical definition is
indeed one bit. It's a short for a binary digit.
And so the information from inspecting a flip coin
is one bit of reduction in your uncertainty.
And you can build upon that and that's a way
of quantifying information. And there's an entire
branch of science and engineering uh information
theory which is just based on that rather austere
definition.
但谈到生命时,显然还涉及其他东西,因为如果我们以细菌为例,你可以取出它的 DNA。这是常规操作。你可以编辑那个 DNA 并把它放回去,让细菌做出一些略有不同的事情。但如果你取出它的 DNA 并随意打乱,只是将那个 DNA 的碱基对随机混洗然后放回去,让它变成纯粹毫无意义的胡话,那么这个细菌实际上就死了。DNA 里的信息总量仍然相同,但它无法执行任何功能,并且只会慢慢分解。换句话说,这就像一本书。如果你把那本书里的词句随机打乱,你会得到一本信息含量相同的书,但它没有任何意义。这就是生命的要义所在。DNA 中的信息——我还可以说,它仅占生物体总信息量的一小部分,在 DNA 之外还有大量我们所谓的表观遗传信息——但无论你审视整体,它之所以如此有效,是因为它具备意义。因此,这就是历经几十亿年作为操作系统被不断完善的软件成分。而当一个细菌分裂产生新的生物体、当它进行复制时,它必须将那些信息、那个程序上传给后代,整个系统才能正常运转。这就是生命运作的方式。如果没有这些指令,它就不是生命,而只是复杂的化学。那么,这最初究竟是如何存在的?那种遗传密码是如何产生的?你知道,这是一种相当精巧、复杂的机制。额,它……是否存在更简单的先驱密码?如果追溯到40亿年前,是否存在使用双联密码而非三联密码的生物?氨基酸的种类是否更少?但是
英文原文
But when it comes to life it's veryclear that there's something else involved
because if we think for example of bacteria
you could take out its DNA. This is routinely
done. You can edit that DNA and put it back and
get the bacterium to do something a bit different.
But if you take out its DNA and just scramble it,
just shuffle the base pairs of that DNA and
put it back so that it's just gobbledygook,
then the bacterium is in effect dead. I've
got the same amount of information in the DNA,
but it's not going to do anything and it will
slowly just decompose. In other words, it's like a
book. If you take the words in that book and then
just shuffle them randomly and then you'd have
a book with the same information content, but it
wouldn't mean anything. And that's the point about
life. The information in the DNA, and I might say
it's only a small part of the total information
content of living organisms. There's a whole lot
of what we call epigenetic information outside
of DNA as well. But you take the whole thing. Uh
it is so effective because it means something. So
that's the software component that's been refined
over billions of years as an operating system.
And uh when a bacterium uh divides and makes
a new organism when it replicates it has to
uh upload that um that uh information that uh
program into the progeny for the whole thing to
function. So this is the way that life works.
Uh and without the instructions it it isn't
life. It's just complex chemistry. So how did
that come to exist in the first place? How did
that genetic code arise? It's, you know, it's a
pretty clever sophisticated sort of thing. Um,
what did it, was there a simpler precursor
code? If you go back four billion years,
were there organisms using a dick code instead of
a triplet code? Were there less amino acids? But
生命起源与信息管理
这种编码信息的概念最初究竟是如何产生的?对我来说,我认为生命起源的关键就在于,构成生命的分子、那些复杂的分子,是如何写出它们自己的代码、它们自己的计算机代码的——因为实质上就是这么回事。这是怎么发生的?我认为这是一个深刻的谜团。我不认为我们已经接近理解那特定的一步了。但对我而言,如果去思考到底在哪个关键节点上可以说它活了,在从纯粹复杂的化学物质走向真正的生命体的路径中,正是出现那种抽象数学代码的节点。我们不知道那是如何发生的,但对我来说,那正是可以说生命起源的节点。
英文原文
how did that notion of coded information uh come about in the first place? I I think that is the for me the point about the origin of life is how did the molecules the complex molecules that make up life write their own code their own computer code cuz that's what it amounts to uh how did how did that happen I think that's a deep mystery I don't think uh we we've got anywhere close to understanding uh that particular step but for me if I think about you know what was the critical point at which you say it's alive uh in in that uh pathway from just complex chemistry to a truly living thing. It's at the point that you get that abstract mathematical code appearing uh we don't know how that that happened but that would be the point for me uh at which you would say it's the origin of life.所以,当我退后一步审视生命的奇迹、它展现非凡本领的方式时,在我脑海中浮现的恰当词汇就是“信息管理”。它是信息管理的方式——不仅仅是比特数量的清点,不仅仅是内容本身,而是信息管理、组织或监督生命活动的方式。因此,这种信息必须处于语境之中。它必须嵌入在一个更大的系统里。它必须在那种更大的尺度上具备生物学功能。这对物理学家来说是非常难以思考的事情,因为我们习惯于通过局域思考,从力和相互作用等角度去理解世界上发生的事情。你知道,就是在某个特定点上正在发生什么。举个例子,你可能会向一个原子核发射一个质子,它打碎了原子核。那么我们如何描述在那次相互作用中发生了什么?它是根据集中在那个核体积内的力来描述的。在试图弄清发生了什么时,我们不会去求助于整个实验室。但谈到生物学时,你必须把有机体作为一个整体来看待。它是整个事物的集体组织,而难点也正在于此。那就是试图理解嵌入在有机体中、储存在DNA以及有机体其他特征中的信息,如何能以监督这种整体组织的方式被调配。我可以举出很多很多例子,但这就是其要旨所在。那就是,什么是那种语义的、有意义的或语境性的信息,即信息外加的东西,它不仅仅是比特的问题。
英文原文
So if I stand back and look at uh the the the magic of life, the way it is uh performing its amazing feats, uh then it it just seems to me that the correct words that come to my mind are information management. It's the way that the information is not just a headcount of bits, not just the content, but the way that information is managing or organizing or supervising what life does. And so that information has to be in a context. It's got to be embedded in a bigger system. It has to have that uh biological functionality on that larger scale. That's a very hard thing for physicists to think about because we're used to understanding what goes on in the world in terms of forces and interactions and so on by thinking locally. You know what is happening at a particular point. Give you an example. You might uh shoot um a a proton at a at a nucleus and it shatters the nucleus. And then how do we describe what goes on in that interaction? Well, it's in terms of the forces concentrated uh in that nuclear volume. Uh we wouldn't appeal to the uh you know the entire lab uh when trying to figure out what's going on. But when it comes to biology, you have to look at the organism as a whole. It's the collective organization of the whole thing and that's the difficulty. It's trying to understand how uh information uh embedded in in the organism stored in the DNA and in other features of the organism as well can be deployed uh in a manner that um supervises that overall organization. There are many many examples that I could cite but that's the gist of it. It's um what is that semantic or meaningful or contextual information that is information plus it's not just a matter of bits.所以我已经说过好几次了,生命的信息内容——如果你愿意,可以称之为指导手册——以及信息管理,所蕴含的远不止于DNA。因此我们有“遗传学”这个术语,基因是DNA中特定字母序列,我们可以将其视为遗传信息。但显而易见的是,还有大量其他被称为表观遗传的信息。它指的就是基因组之外。问题是,这些信息储存在哪里?存在着相互开启和关闭的基因网络。因此,这些网络是信息可以储存的一个地方。还有另一种方式,那就是DNA并不像你在教科书里看到的那样平摊着放在那里。它全都以复杂的模式折叠起来,而那些模式本身就能储存信息。但真正的问题在于,基因组之外的信息是否能一代代留存下来?它能够被遗传吗?
英文原文
So I've said several times that the information content of life it the book of instructions if you like and uh the information management is in much more than the DNA. And so we have this term genetics and the gene is a particular sequence of letters in DNA and we can think of that as genetic information. But it's very clear that there is a lot of other information which is called epigenetic. It just means outside of the genome. The question is where is this information stored? There's networks of genes that switch each other on and off. And so these networks are one place that information can be stored. There's another way which is the DNA just doesn't sort of sit there like you see in the textbooks. It's all folded up in complex patterns and those patterns themselves can store information. But the question is really whether information outside of the genome can survive uh from one generation to the next. Can it be inherited?表观遗传与跨代遗传
早在19世纪,当生命在数十亿年间发生演化这一点变得明确时,关于这可能如何发生存在着相互对立的理论。其中之一当然就是著名的达尔文随机变异与自然选择理论;但另一个则出自法国生物学家拉马克。拉马克的想法是,有机体在有生之年获得的特征或许能以某种方式传递给其后代。给你举个稍微平淡点的例子。长颈鹿的长脖子,你知道的,它们为了吃到越来越高的食物而伸长脖子。所以也许一只长颈鹿在一生中不得不把脖子伸得更高,因而获得了一条拉长的脖子,随后就会将其传递给它的后代。这样它的幼崽就会拥有比平均水平更长的脖子。换句话说,你在有生之年获得的特征会被遗传下去。
英文原文
Back in the 19th century when it became clear that life has evolved over billions of years there were rival theories about how this might happen and one of these is of course well known as Darwin's theory of random variation and natural selection but the other was due to the French biologist and Lamar and Lamar had the idea that uh maybe characteristics that organisms acquired during their uh lifetime could somehow be passed on to their progeny and give you a sort of trivial example. Giraffes long necks, you know, they're stretching to get food higher and higher. So maybe a giraffe that had to stretch its neck even higher during its lifetime and sort of acquired an elongated neck as a result would then pass it on to its progeny. So it's its babies would have longer necks than average. In other words, the characteristics you acquire during uh a lifetime would be passed on.而那个理论失宠了。反例似乎很容易找到。比如想一想一位铁匠,每天敲敲打打练出了巨大的肌肉。这位铁匠生出的婴儿会有大块肌肉吗?答案是否定的。看起来铁匠的基因,如果你愿意这么说的话,在早期某种程度上就固定了,并传递给后代,与铁匠一生中的活动毫无关系。这是一个相当有争议的话题,被称为表观遗传。现在非常明确的是,它可以在细胞层面起作用。你知道,皮肤细胞能产生皮肤细胞,肝脏细胞能产生肝脏细胞,诸如此类。因此就其身份而言,它们拥有相同的DNA,但在这些不同细胞中,这种身份、即基因表达是不同的,然而它却能被传递下去。但你能拥有跨代的表观遗传吗?我的意思是,一个有机体是否可能把并非存在于其基因中、而是存在于整体身体中的某些信息,传递给它的后代?
英文原文
And that theory fell out of favor. Um it seems very easy to find counter examples. Think for example of a blacksmith um acquiring huge muscles by sort of hammering away uh every day. Does the blacksmith have babies with born with big muscles? Um well the answer is no. Uh it looks like uh the uh the the the genes in the the blacksmith's genes if you like uh are sort of fixed uh early on and passed on to the offspring and have nothing to do with the activity that the uh of the blacksmith in his lifetime. And this is a rather controversial subject. It's called epigenetic inheritance. Now it's it's very clear it can work at the cellular level. um you know skin cell can make a skin cell and a liver cell can make a liver cell and so on. So it's identity uh they have identical DNA but the identity the gene expression is different in these different cells uh and yet it can be passed on but can you have intergenerational epigenetic inheritance? What I mean by that that is it possible uh for an organism uh to pass on some of the information not in its genes but in the in the the body as a whole pass that on to its progeny.极具争议。在植物中显然会发生。但人呢?你知道,你在有生之年所做的事情是否可能会影响你的孩子,无论是让他们更高、更矮、更瘦还是更胖,甚至影响他们的行为?这可能吗?有一点微弱的证据表明可能如此,但正如你可以想象的那样,这是有争议的。任何涉及人类的事情都会变成极具争议的问题。接下来问题就是机制。那将如何通过卵子和精子传递下去?它们除了DNA之外,是否可能携带影响孩子发育的其他某种化学或结构信息?这似乎是一个悬而未决的问题。我是可以被说服的。我知道一些关于小鼠的实验表明这是可能的,在那种情况下,甚至可以通过父系、通过精子,使后代在某种程度上受到父亲经历的影响。
英文原文
Very controversial. Clearly happens in plants. But what about people? You know, is it the case uh that what you do in your lifetime might affect your children uh whether they be taller or shorter or thinner or fatter or you know even their behavior. Is is that possible? There's a little bit of evidence that it might be uh but it's contentious as you might imagine. Anything involving human beings becomes a very contentious issue. And then the the problem is the mechanism. How would that be be passed on uh through the eggs and and the sperm? Is it possible that they could carry with them something other than the DNA some chemical or structural information that would affect how uh the children develop? Um and it it seems like an open question. I can be uh convinced. I know of some experiments with mice that show that it is possible uh even through the uh the male line the the sperm uh for the progeny to uh to be influenced in some way by the experiences of the fathers in that case.所以,很容易想到这可能发生的方式。塔夫茨大学的迈克尔·莱文及其同事利用涡虫做了一些令人惊叹的实验。它们非常受欢迎,因为有一头一尾。如果你把一条虫切成两半,头部会长出尾巴,尾巴会长出头部。这样你就花一条虫的代价得到了两条虫。你可以继续这么做,把它切来切去。实际上,你可以把一条这样的虫切成,你知道,100个不同的截段。不知何故,这些截段记得哪边是前、哪边是后,并且能长成100条不同的虫。这都非常不可思议。现在,你可以对其进行化学操控,从而做出双头虫和双尾虫。但现在你问这个问题:如果你把一条双头虫从中间切开会发生什么?那会重构成原本的虫子吗?变成两条有一头一尾的虫子?不。事实证明,双头虫会长成另外两条双头虫。换句话说,这就像一个全新的世系。因此,在城另一头的实验室里,你可以有一整群双尾虫;而在你的实验室里,你有一整群双头虫。你可能会认为这是不同的物种,但它们有着完全相同的DNA。所以这表明,这些虫子的形态,即生物学家所用的技术术语“表型”,取决于远不止DNA内容的东西。那种信息不知何故被储存了下来——可能是电性的,可能是化学性的,人们并未真正搞懂——不知何故被储存,并且能在事后将虫子重构成那种特定的形状。因此,这是一个线索,表明仅仅关注基因,我们正在错失图景中很大的一部分。
英文原文
So um it it's easy to think of ways in which this might happen. There's some amazing experiments by Michael Levvin and his colleagues at Tus University using pleneria. They're very popular because it's got a head and a tail. And if you chop a worm in two, the head grows a tail and the tail grows a head. So you've then got two worms for the price of one. And you can go on doing that, sort of chopping them up. In fact, you can chop a worm like that up into, you know, 100 different sections. Uh, and somehow these sections remember which was the front and which was the back and they grow into 100 uh different worms. And that's all very amazing. Now, you can chemically manipulate them such that you can make two-headed worms and two-tailed worms. But now you ask the question, what happens if you chop a two-headed worm in half? Does that reconstitute the original worm? Two worms now with a head and a sail. No. It turns out that the two-headed worm makes two more two-headed worms. In other words, it's like a new lineage. And so in a lab across town, you can have a whole population of two-tailed worms. And in your lab, you've got a whole population of two-headed worms. You might think these are different species, but they have identical DNA. So, this shows that the morphology, the actual the phenotype is the technical term that biologists use uh for uh these worms depends on much more than the DNA content. It's that information is somehow stored, possibly electrically, possibly chemically. it's not really understood somehow stored and can reconstitute the worms into that particular uh shape afterwards. So that's a clue that in just focusing on genes we're missing a big part of the picture.生命、熵与物理定律
第二章:生命、熵与我们缺失的定律。有一位著名的科学家叫罗尔夫·兰道尔,曾说过“信息是物理的”这句话,它深深印在了我和许多其他人的脑海中。就我们能在抽象层面上谈论信息而言,正如你走进计算机科学系,与一位软件工程师交谈,他们在写所有这些计算机代码,并且谈论它时仿佛它是一件独立的事物。但当然,它始终必须被实例化在某种物理基质中。因此,信息并不是能够自行在以太中漂浮、自顾自活动的某种东西。它必须被实例化在物质中。于是我们便遇到了这个非常有趣的问题:物质在做物质必须做的事。有描述它应当如何运作的物理定律。我们不能说,噢,就因为正在编码信息,它就会有不同的行为表现。这些定律是数学关系,这是要传达的一个真正重要的点。因此,当物理学家谈论定律时,他们指的不仅仅是思考世界的方式。他们指的是作为数学关系的组织原则。
英文原文
Chapter 2 life entropy and the laws were missing. There was a famous scientist called Rav Lando who is uttered the phrase information is physical and it stuck in my mind in the minds of a lot of other people. In as much as we can talk about information in the abstract just as you you go and uh to a computer sciences department, you talk to a software engineer uh and they're writing all this uh computer code and uh uh and they talk about it as if it's um a separate thing. But of course it always has to be instantiated in material uh some sort of material substrate. And so information isn't something that can just sort of float around in the ether on its own doing its own thing. It's got to be instantiated in matter. Uh so then we come up against this very interesting thing that matter does what matter has to do. It's got laws of physics that describe how it should behave. uh and we can't say oh just because it's encoding information um you know it's going to behave differently. These laws are mathematical relationships and that's a really important point to get across. So when physicists talk about laws uh they don't just mean um ways of thinking about the world. They mean organizing principles which are mathematical relationships.给你举个简单的例子。你可能想在电脑上玩国际象棋。屏幕上的图形按照国际象棋的规则移动。那么,这是否意味着在电路底层,物理定律正在与国际象棋的规则争吵?你知道,到底谁会在这里获胜?当然,这是完全协调一致的。只是物理定律——我们又回到这一点——是在局域起作用的。我们所理解的标准物理定律是局域效应。国际象棋的规则则关乎屏幕上图形的整体组织以及博弈规则等等。因此,我们在这里所面对的是,如果我们谈论生命或意识,我们试图去理解、试图调和描述全局、语境或事物整体安排的定律,与底层的局域定律。
英文原文
And give you a simple example. You might want to play chess on your computer. the shapes on the screen move around according to the laws of chess. Well, does that mean that uh down among the secretary you got the laws of physics sort of squabbbling with the laws of chess? You know, well, well, you know, who's going to win here? Uh, of course, it's perfectly consistent. It's just that the laws of physics, we come back to this, that operate locally. The standard laws of physics we understand are local effects. the laws of chess have to do with the overall organization of the shapes on the screen and the um the rules of the game and so on. Uh and so we're uh we're dealing here with trying to understand if we want to reconcile if we're talking about life or consciousness, we want to reconcile laws which describe the global or the context or the overall arrangement of things with the local laws at the bottom.有些人认为生命的奥秘全在热力学第二定律,认为它逆转了从有序到混沌的趋势。在这里,活的有机体走向了反方向。它们从有序中创造有序。而这向一些非科学家暗示了存在某种神秘莫测的额外成分、生命力,或某种精神性的东西,或神明的指引之手等,在促成这些效应。那是对热力学定律的彻底误解。我必须强调,活的有机体是开放系统。严格表述的第二定律指出,在孤立系统中熵永远不会减少。但活的有机体不是孤立系统。存在着来自其环境的能量和物质的吞吐通量。如果你愿意,可以用一种很好的说法:它们可以把自己的熵或混沌排放到更广阔的环境中。所以,当我们进食时,这有助于我们维持自身的内部秩序,但我们在分解食物,并且
英文原文
Some people think that the mystery of life is all about the second law of thermodynamics that it's going against the trend from order to chaos. Here living organisms go the other way. They create order out of order. And that has suggested to some non-scientists that there's some sort of mystical mysterious extra ingredient or a life force or some something sort of spiritual or the guiding hand of a a deity or something which is uh uh bringing these effects uh about. Um and that's a total misunderstanding of the laws of thermodynamics. I must emphasize that living organisms are open systems. The second law strictly stated says that in a closed system the entropy can never go down. But living organisms are not closed systems. There's a throughput of energy uh and material from their environment. Um and uh if you like good way of putting it is that they can export their entropy or their chaos into the wider environment. So, uh, when we eat food, um, this, uh, helps us maintain our own internal order, but we're breaking the food down and,在获取食物的过程中,我们首先就会在周围环境中造成大量的混乱和无序。我想说的是,这并不是什么深不可测的谜团。我的冰箱也能完成类似的壮举,因为热力学第二定律最好的表述之一就是热量自发地从热处流向冷处。当然,我的冰箱所做的事情正是我刚才说的违背热力学第二定律的事。它把热量从冰箱内部抽取出来并排放到厨房里,也就是把热量从低温区域移到了高温区域。这违背了热力学第二定律的趋势,但它能够做到这一点,是因为我为它支付了电费。你看,这并不是自发发生的。如果把系统看作一个整体,其中包括供电设施和城另一头的发电机,所有这些都意味着熵增加了,但在局部范围内,熵是可以减少的。我们可以把生物体看作是一种小小的“熵井”,如果你愿意这么称呼的话,它们能够实现违背第二定律的表现,但这是以更广阔的环境为代价的。
英文原文
uh, in acquiring the food in the first place,we're creating a lot of sort of chaos and
disorder in the surrounding environment. I
I should say that this is not deeply mysterious.
My refrigerator can perform a similar feat because
one of the best expressions of the second law
of thermodynamics is that heat flows from hot
to cold spontaneously. Now my refrigerator of
course does exactly what I've said is against
the second law of thermodynamics. It takes heat
from inside the refrigerator and pumps it out
into the kitchen which is taking heat from cold
region and putting it out into the hot region.
going against the trend of the second law of
thermodynamics, but it can do that because I'm
paying the electricity bills for it to happen.
You see, it's not happening spontaneously. If
you take the system as a whole, that includes the
electricity supply and the generator across town,
all of that means that the entropy goes up, but
locally it can go down. We can think of living
organisms as just sort of little entropy wells
if you like that can achieve this going against
the second law but at the expense of the wider
environment.
关于生命与热力学第二定律的另一种思考方式指出,信息就像负熵,如果你获取了关于某样事物的信息,你就在减少混乱或无序的程度。热力学的奠基人之一詹姆斯·麦克斯韦在给朋友的一封信中提出了一个奇妙的想法:他设想了一个装着气体的盒子,中间有一层隔膜,隔膜上有一个小孔,然后那些分子中的一个会穿过小孔去到盒子的另一侧,反之亦然。在平衡状态下,两个方向上的往来是平衡的。但现在设想一下,他说,如果你有一个小生物——后来被称为“小妖”——它能操作一个快门机构,并且能看到分子迎面而来。假设小妖看到一个快速运动的分子从盒子的一侧过来,它会想:“好的,我打开快门让它穿过去。但慢速运动的分子将被拒之门外。”那么随着时间的推移,在隔膜的另一侧就会聚集起快速运动的分子,从温度的角度来看,这就意味着更高的温度。分子振荡得更快意味着那一侧更热。因此,小妖就能够在两侧之间制造出温差,这完全违背了热量从热处流向冷处的热力学第二定律。这就是它被推向相反方向的一个例子。不是像做同样事情的冰箱那样通过支付电费,而是通过利用关于分子运动的信息。
英文原文
Another way of thinking about lifeand the second law of thermodynamics says that
information is like negative entropy that if you
gain information about something you're reducing
the amount of chaos or disorder and one of the
founders of thermodynamics James Maxwell came up
with a curious idea in a letter to a friend in
which he imagined a box of gas with a membrane in
the middle and a little hole in that membrane and
then one of those molecules would go through
the hole and go to the other side of the box
and vice versa. And in equilibrium, there'd
be a traffic in both directions that would
balance out. But now imagine he said that you had
a little creature later came to be called a demon
who could operate a shutter mechanism and could
see the molecules coming along. And supposing the
demon saw a fastmoving molecule coming from one
side of the box and would think, "Yes, I'll open
the shutter and let that one go through. But the
slowmoving molecules will be rejected. Then over
time there'd be an accumulation of fastoving
molecules on the other side of the membrane
which in terms of temperature would mean a higher
temperature. The molecules jiggling faster means
it's hotter on that side. So the demon would be
able to create a temperature difference between
the two sides in complete violation of the second
law of thermodynamics that says heat goes from
hot to cold. This is an example of it being pushed
in the other direction. Not by paying electricity
bills for a refrigerator which does the same um
but by using the information about the molecular
motions.
所以这表明信息是一种燃料。它是一种在原则上可以用来制造一台小引擎的东西。你制造出温差,然后你就可以利用这个温差驱动马达,完全利用来自信息的力量,将信息作为燃料。有趣的是,大自然在数十亿年前就发现了麦克斯韦妖,因为我们的身体里充满了它们。它们在我们体内吟唱运转。有泵、杠杆和各种各样的小机构、小引擎等等,它们在执行这些操作,在热力学第二定律的边缘游刃有余。我必须强调,它们并没有违背热力学第二定律,但它们非常接近我们所认为的完美状态,非常接近热力学第二定律所允许的理论极限。因此,生命已经将这种信息处理,或者说将信息作为燃料,精细化到了拥有大批这种小分子机器的地步,它们实际上就是执行生命事务的麦克斯韦妖。而整个宇宙毫无疑问正沿着单行道滑向越来越高的熵状态,滑向越来越少的可利用能源,这是一个宇宙学层面的故事。因此,生命并不是在逆热力学第二定律的潮流而行,它只是在其边缘游走。
英文原文
So what this suggests is that informationis a type of fuel. It's something uh which could
be used uh to in principle create a little engine.
you create a temperature difference and then you
could run a motor off that temperature difference
uh using entirely from the power of information
that information as a fuel. Now the interesting
thing is that nature discovered Maxwell demons
billions of years ago because our bodies are full
of them. They're sort of chanting away inside us.
um uh there are pumps and and levers
and all sorts of little mechanisms,
little engines and so on that are carrying out
uh these um these operations playing the margins
of the second law of thermodynamics. I must
emphasize they don't violate the second law
of thermodynamics but they come very close uh
to what we might regard as the uh perfection
uh very close to the theoretical limit permitted
by the second law of thermodynamics. So life has
refined this information processing or information
as fuel uh right down to the point of having lots
of legions of these little molecular machines uh
which are effectively Maxwell demons carrying out
the business of life and the universe as a whole
is un undoubtedly on a one-way slide to a higher
and higher entropy state less and less useful
sources of energy and that's a cosmological story.
So life is not going against the trend of the
second law of thermodynamics. It's simply playing
the margins of it.
如果我可以回过头来说一下,我们之前谈到了薛定谔。薛定谔写了这本了不起的书《生命是什么?》。他在书中说,我们必须准备好发现一种在其中起作用的新型物理定律。这里的关键词是“型”,而不仅仅是“新的物理定律”。换句话说,他并不是在说:“我们所知道的所有物理定律都在这里,还会有一条我们尚未发现的定律来解释生命。”那将是一种新型的定律。在我的职业生涯中,我非常认真地对待了这一点。我认为确实需要一种新型的定律。它需要的不仅仅是另一种力或类似的东西。它需要的是一种关于定律的全新方式、全新概念。这也正是我已经暗示过的,信息与物质——硬件与软件——在生物体中相互作用的方式,我们目前没有任何类似的法则框架可以在普适的基础上对此进行描述。我们确实需要某种东西,能够把生物学信息置于语境之中,也就是说,我已经解释过基因是一组指令,供特定的分子系统去执行某件事,比如制造蛋白质,它具有生物学功能,我们必须将生物体的全局语境与局部指令集联系起来。
英文原文
And if I might just back upand say that we talked earlier about Schroinger.
Shreddinger wrote this remarkable book, what is
life? And in it he said we must be prepared to
find a new kind of physical law operating in it.
The operative word there is kind, not just a new
physical law. In other words, he he wasn't saying,
"Well, um there's all the laws of physics we know
and there'll be one that we haven't discovered yet
that will explain life." Uh it would be a new kind
of law. And I've taken that very seriously uh
during my career. And I think that the that it
does need a new kind of law. It doesn't just
need another force or something of that sort.
Uh what it needs is a a new way of a new concept
of law. uh and it's something which I've already
hinted at that the the the way information and
uh matter the hardware and the software the way
they interact in living organisms uh we don't have
any sort of lawike framework uh on a general basis
for describing that we do need something uh that
would uh that put that uh biological information
in context that is I've explained how a a gene is
a set of instructions For a particular molecular
system to do something like make a a protein, it
has biological functionality, we have to relate
the global context of the organism to the uh
local instruction set.
如果我们谈论万有引力定律之类的东西,为什么一个物体会下落?是因为该处的引力场作用于它。这是一个局部的事件。当我们谈论生物体时,我们不知怎的必须考虑到整个系统的组织、集合体的语境,我们必须将它嵌入到某种新型的物理定律中。我认为仅靠发明新的局部定律是无法做到这一点的,我们必须对定律有全新的思考方式:底层是物理定律,顶层是组织的高层定律,我们必须以某种方式将这两者结合起来,人们已经尝试过这么做。我的意思是,我并不是说这是一件毫无希望的事。很多人做过尝试来描述通常被称为“自上而下的因果关系”的现象。在全局层面发生的事情,正在影响局部层面发生的事情。你可以写下方程式之类的东西,其中一些相当成功,但我认为我们还没有在真正基础的层面上理解更高层次的组织与更低层次的物理定律究竟是如何以根本的方式结合在一起的。从广义上讲,有一些想法在流传,我不会深入去谈,它们有点技术性,这都还是非常初步的,但我认为,如果没有像薛定谔所要求的那种新型物理定律,我们将永远无法完全解释生命。
英文原文
If we talk about lawof gravitational or something, why does an object
fall? It's because the gravitational field at this
point is acting on it. It's a local thing. when
we're talking about uh living organisms uh somehow
we have to take into account the organization of
the entire system the context of the assemblage
uh and we've got to embed that in some sort of new
type of physical law I think we're not going to do
this just by inventing new local laws we've got
to have a new way of thinking about laws laws of
physics at the bottom level with some higher level
laws of organization at the top level and we've
got to mesh these two in some way that people have
tried. I mean, I'm not not saying this is a lost
cause. Been lots of attempts um to uh describe
what's often called top- down causation. Uh what's
happening at the global level, it's affecting
what's happening at the at the local level.
uh you can write down equations and things and
some some of these are moderately successful but
I don't think we've really understood at a truly
fundamental level how the uh higher levels of
organization and the lower levels of the laws of
physics really mesh together in a fundamental way
uh in a general sense there's some ideas
slushing around I won't get into them they're
a bit technical um this is all very tentative
uh but I think we're never going to fully
explain life without having that new kind of
physical law as Schroinger was asking for.
第三章:我们孤独吗?寻找第二次生命起源
提出生命定义以及生命起源的部分困难在于,我们几乎完全受限于地球上的生命。因此,我们可以研究早期地球上的条件是什么,以及今天在地球上维持生命所必需的条件是什么。但我们不知道这两者是否是同一回事。情况可能是,生命的起源需要一组条件,但为了让它繁盛,需要的是另一组不同的条件。我们知道生命是可以移动的。也许早期火星是生命起步的更好场所,但早期地球是生命繁盛的更好场所。但是因为生命——原始的微生物生命——可以通过撞击喷射物从火星到达地球。这没有问题。在火星上开始,在地球上繁盛。我们真的不知道。因此,当我们去寻找地球之外的生命时,往往会倾向于认为,我们应该寻找类地行星。
英文原文
Chapter 3, are we alone? The search for a secondgenesis. Part of the problem about coming up with
a definition of life uh and the origin of life
uh is that uh we we're guided almost entirely
by life on Earth. And so we can look at what were
the conditions uh on the early earth and what are
the conditions necessary to sustain life on earth
today. Now we don't know that these were the same
things. It may be uh that the origin of life
requires one set of conditions but for it to
thrive it's a different set of conditions. We
know life can move around. You know maybe early
Mars was a better place for life to get going
but early Earth was a better place for it to
flourish. Uh but because life primitive microbial
life can go from Mars to Earth in impact ejector.
That's no problem. Starts on Mars, flourishes on
Earth. Uh we we don't really know. So when we're
going to look for life beyond Earth, um there's
a tendency to think, well, we should look for
Earthlike planets.
当我还是个学生的时候,我对地球以外存在生命的想法非常感兴趣。但在那些日子里,声称对此感兴趣就好比声称对寻找仙子感兴趣。当时人们认为地球以外不可能有生命是不言而喻的,因为生命是如此复杂,它只可能发生一次。例如,发现DNA结构的弗朗西斯·克里克曾说过,生命看起来几乎是一个奇迹,它启动所需的条件是如此之多。因此,几十年前盛行的观点是,生命是一场离奇古怪的意外,是化学上的侥幸事件,其不可思议的程度使得在整个宇宙中只能发生一次。然后几十年来,钟摆发生了摆动,所以现在非常杰出的科学家们都准备好说宇宙中充满了生命。但我经常对此提出批评,我说,我读书的时候没人把这当回事。现在你们都说宇宙中充满了生命。改变了什么?我经常得到的回答是,哦,我们现在知道生命可以生存的环境范围比我做学生时所知道的要广阔得多。过去人们认为,即使是耐受力极强的微生物也无法在高于50或60摄氏度的温度下存活,后来人们发现,有些生物生活在温度高得多的温泉中,其他物理条件也是如此——极端严寒、极度化学污染、极端盐度。这些在上述条件下生存的生物的总称是“嗜极生物”。
英文原文
When I was a student, I wasreally interested in the idea of life beyond
Earth. But in those days, one might have professed
an interest in looking for fairies. was considered
uh self-evident that there couldn't be any life
beyond earth because life is so complex it would
have happened only once and Francis Crick for
example who discovered the structure of DNA
said life seems almost a miracle so many of the
conditions necessary for it to get going so the
prevailing view decades ago was that life is a a
bizarre freak accident a chemical fluke of such
improbability that you'd only get it once in
the whole universe universe and then over the
decades the pendulum sort of swung and so now very
distinguished scientists are prepared to say that
the universe is teeming with life. Um but uh I
often criticize that by saying well when I was a
student nobody took that seriously. Now you're all
saying it's teameming with life. What's changed?
And the answer that I often get is oh well we know
that life can now live under a much wider range of
circumstances than when I was a student. used to
be thought that uh even hardy microbes couldn't
survive temperatures above you know 50 or 60
degrees Celsius then it was found that there
are organisms living in hot springs of much higher
temperatures than that and same goes for uh other
physical conditions extremes of cold extremes of
chemical pollution extremes of salinity um and so
these collective noun for these organisms that
survive under these conditions is extreophiles
于是人们指着这点说:“看,我们现在知道生命可以在如此广泛的条件下存活。”这极大地增加了我们在外太空可能去搜寻以发现生命的地盘面积。确实,我们能够去寻找的地方可能会多上10倍或类似的倍数。但如果从非生命孕育出生命的几率是万亿万亿分之一,那么你知道,多出10倍的可能并不会起到很大作用。我希望能有一个证明或者发现,哪怕仅仅是另一个生命样本就行。哪怕是在地球上发现一种属于生命但非我们所知的微生物,就足够了。地球上若有两种生命样本,必然意味着到处都会有生命。每个人都有自己最偏爱的寻找场所。我倾向于认为火星是最好的可能性,但人们也非常关注太阳系寒冷的外部卫星:木卫二(Europa)和土卫二(Enceladus)。那是土星的一颗卫星,它拥有冰壳,冰壳下方是一片液态海洋。冰壳上有裂缝,从这些裂缝中喷出气体,卡西尼号任务曾飞穿这个羽状喷流并检测到了有机分子。
英文原文
And so people point to that and they say, "Well,now we know uh that life can survive under such a
wide range of conditions." That greatly increases
the amount of real estate out there that we might
search uh to uh to to find life. And it's true
that it may be by a factor of 10 or something
that there are more places that we could look. Uh
but if the odds against life forming from non-life
uh are one in a trillion trillion, you know, an
extra factor of 10 isn't going to help you very
much. Uh I would like a demonstration uh or of
the discovery, just one other sample of life. Uh
one one microbe here on Earth that is life, but
not as we know it would do it. Two two samples
of life on Earth surely means that there would
be life everywhere. Everyone has their favorite
place to look. I like to think of Mars as the best
possibility, but there's a lot of emphasis on the
frigid outer moons of the solar system, Europa and
Enceladus. That's a moon of Saturn. It's got a icy
crust and underneath it is a liquid ocean. The icy
crust has cracks in it and spewing out of these
cracks are gases and the Cassini mission flew
through this plume and detected organic molecules.
然而,“有机”并不一定意味着“活的”。有机分子是复杂的碳分子。它们可能是活体生物的产物,也可能仅仅是复杂碳化学反应的产物。你如何区分它们呢?我们如何知道从这个喷流中喷出的物质中,是否有曾经存活过但被碾碎的物质,或者可能仍然是活着的?你想做的是在航天器上安装一台仪器,飞穿那个羽流,收集喷出的物质,并对它是否属于生命给出裁决。我们还不完全清楚这会是一台什么样的仪器。什么才会是生命的决定性标志,或者就此而言,什么能把某种曾是……的事物区分开来。
英文原文
Now, organic doesn't necessarily mean living.Organic molecules are complex carbon molecules.
They may be a product of living organisms or
they may just be a pro product of complex carbon
chemistry. How can you tell the difference?
How would we know whether there is anything
spewing out in this plume uh that was maybe once
living and got mashed up or is maybe still living?
What you'd like to do is have an instrument to put
on board uh a spacecraft that would fly through
that plume, collect uh the material spearing
out and would deliver a verdict uh on on the uh
whether it's living or not. Uh we don't know quite
what that instrument would be. what what would be
um a definitive sign of life uh or for that matter
what would distinguish between something that was
死亡、休眠与生命的界限
活着的,而现在被分解成了各个组成部分。嗯,如果你愿意的话,那就是死亡。那会是一个死亡测量仪。嗯,我们有死亡测量仪吗?某种能够说“是的,它死了,但它曾经活着”,相对于“不,它还不太算活着”,嗯,你知道,相对于“它是活着的”的东西?这立刻就会把你引向一些非常有趣的问题。显然,我们往往会沉湎于人类的死亡以及意识的丧失,人们会担心,你知道,在死后是否存在某种形式的存在等等。但我想更科学一点,把它简化成更简单的事物来思考。
英文原文
living and is now broken down into components. Uh so that's death if you like. That would be a death meter. Uh do we have a death meter? Something that could say yes it's dead but it was living versus no it isn't quite living yet. Uh you know versus it is alive. And that immediately gets you into uh some very interesting questions. We tend to obviously dwell on death for human beings and the loss of uh of consciousness and people worry about you know well is there some sort of existence after death and so on. But I' I'd like to uh to be a bit more scientific uh boil it down to something much simpler uh to think about.嗯,如果我们拿比方说一个细菌为例,如果你把一个细菌冷却到比方说液氮的温度,它就会进入休眠。嗯,有被困在冰里的细菌,例如,在数百万年后可以被类似复苏过来,或者被困在盐晶体里,或者在冰箱里。它们没有死,但它们也没有在活着。嗯,我觉得这有点像一只钟表。那么,停走的钟表还是一只钟表吗?如果你让它重新走动起来,它仍然具有报时的潜力。但如果它是一只停走的钟表,它并不是一只死掉的钟表,而是一只休眠的钟表。嗯,细菌也是同样的情况。嗯,它们在被冻结时并没有死。嗯,它们只是处于休眠状态,而且它们可以完全展现地重新活过来。
英文原文
uh if we take um say a bacterium if you uh cool a bacteria a bacterium down to say liquid nitrogen temperatures it become dormant. Uh there are uh uh bacteria which have been trapped uh trapped in ice uh for example uh and can be sort of resuscitated after millions of years or trapped in salt crystals uh or in in a fridge. They're not dead but they're not living either. Uh, and I think of it a little bit like a clock. Well, is a stopped clock. Still a clock. It still has the potential to tell the time if you get it started again. But if it if it's a stopped clock, it's not a dead clock. It's a dormant clock. Um, and the same thing with bacteria. Uh, that they're not dead when they're frozen. Uh, they're simply dormant and they can uh come alive again uh in the full expression.但这引出了一个更深层的问题,因为完全有可能生命已经通过撞击抛射物从地球传播到了火星,或者从火星传播到了地球。我们知道火星和地球不时会被彗星和小行星撞击,将岩石溅洒到整个太阳系各处,有机体可以搭乘这些岩石的便车,从火星旅行到地球,或者从地球旅行到火星。现在,显然后者是可能的。我们不知道这是否发生过,但这看起来完全有可能已经发生过。嗯,在行星际空间中最大的危险并不是寒冷,因为这些微生物会进入休眠。嗯,实际上是辐射。因此,坐在太空中的一块岩石内部,一颗休眠的细菌将受到宇宙射线以及来自岩石本身的某些辐射的轰击。因此,它在旅途中会遭受损伤。假设要经过一百万年它才最终撞击地球。嗯,它还会重新活过来吗?嗯,在超过不可逆转的点之前,它能够承受多少损伤?我想表达的观点是,一个细菌到底是活的还是死的?你可以把它冷却下来,让它停止工作,它可以承受一定程度的损伤,但在某个特定的点上,它就无法再重新启动了,那时你也许就可以宣布它已经死亡。
英文原文
But now that raises a further question because uh it's entirely possible that life has uh uh traveled from Earth to Mars or Mars to Earth inside impact ejector. We know Mars and Earth are hit from time to time by comets and asteroids that splatters rocks all around the solar system and organisms can hitch a ride uh in these rocks and travel from Mars to Earth or Earth to Mars. Now uh obviously that is possible. We don't know if it's happened but it seems entirely likely that it would have done. Uh the biggest hazard in interplanetary space is not the cold because these microbes would become dormant. Um it is in fact the radiation. So sitting inside a rock uh in space um a dormant bacterium is going to be bombarded by cosmic rays and some radiation from the rock itself. And so it's going to sustain damage during its journey. And supposeding it's a million years before it finally hits the earth. Uh will it come alive again? Uh how much damage can it sustain before it's gone beyond the point of no return? The point I'm trying to make is that um is a bacterium alive or dead? You can cool it down and stop it working. uh and it can sustain a certain level of damage but at some particular point it won't start up again and then you might pronounce it to be dead.生命仪与“近生命”的难题
但现在让我们考虑一个更复杂的情况,比如土卫六(泰坦),土星的卫星,土卫六非常寒冷。它不太可能拥有我们所知的那种生命,但它充满了有机分子。它的大气中就像是一场光化学烟雾。我们可以想象,它一直在进行某种宇宙级的米勒实验。它一直在酝酿前生物化学反应达40亿年、45亿年。嗯,所以,你知道,它是否成功制造出了生命,哪怕那不会完全是我们所知的那种生命?嗯,我们又该如何知道呢?想象一下,你向土卫六发送了某种生命测量仪,它穿过大气层下降,然后给出了一个判定结果。它可能会说:“嗯,我们在土卫六上没有发现任何生命,但它已经走完了通向生命之路的93.4%。”或者它只走完了通向生命之路的,你知道,5%。嗯,对此你会怎么看?嗯,我刚才说的似乎有点荒谬。嗯,我们没有——要给生命提出一个定义就已经足够难了。嗯,我们并没有真正关于“接近生命”的定义。我们无法仅凭观察就判断它快要到了。你知道,再给它十亿年,它可能就会产生生命。我们甚至都不知道该如何去思考这个问题。
英文原文
But now let's consider a more complicated case like Titan moon of Saturn and Titan's very cold. It would be unlikely to have life as we know it but it's full of organic molecules. It's like a prochemical smog in its atmosphere. We can imagine that it's been carrying out like a sort of uh cosmic milleri experiment. It's been uh cooking up prebiotic chemistry for 4 billion years, 4 and a half billion years. Um and so uh you know has it did it succeed in making life even if it wouldn't be life quite as we know it. Um and how would we know? Imagine you sent um some sort of life meter to Titan and it went down through the atmosphere and it then uh delivered a verdict. It uh might say, "Well, uh we didn't find any life on Titan, but it did get 93.4% of the way to life." Um or it only got, you know, 5% of the way to life. Uh you know, what would you make of that? Well, what I just said seems sort of ridiculous. Um we don't have it's hard enough to come up with a definition of life. Um we don't really have a definition of almost life. We we couldn't tell by looking uh that it was nearly there. You know, give it another billion years and it might make life. We we don't even know how to think about that.嗯,那是一个非常好的比喻。生物学家理查德·道金斯写过一本书叫《攀登不可能之峰》。它探讨的是生命始于非常简单的阶段,仅仅是微生物,而今天我们拥有了整个复杂的生物圈这个问题。有些人觉得这不可思议。嗯,但他喜欢描述它的方式是,这就像爬山一样,每一步你获得更多的复杂性、更多的秩序等等,都可能是非常小概率的。嗯,但这正是自然选择所做的事情。它的作用就像棘轮一样,锁定了高效的、更复杂的秩序,并淘汰掉那些效果不太好的秩序。于是,你艰难地一步一步一步攀登这座可能之山。嗯,当然,它并不是始于微生物的。有一座始于化学的可能之山。你必须一路从简单化学攀登到复杂化学,再到生命化学——有生命物质的化学。嗯,你在那种前生物意义上该如何攀登那座可能之山呢?嗯,是否有任何方法来测量在可能之山上的海拔高度会是多少?我们能否审视一种特定的复杂化学混合物,给它一个概率,并说出它距离实际形成生命究竟有多近?
英文原文
Um and that's very good metaphor. Richard Dawkins, the biologist, wrote a book called Climbing Mountain Probable. And it addresses the question of life started out very simple, just microbes, and today we have the whole complex biosphere. And some people find that miraculous. Uh, but the way he likes to describe it is that um it's it's it's a like a climbing a mountain and each step might be very improbable that you get more complexity, more order, and so on. Uh but that's what natural selection does. It is acts like a ratchet locking in the um efficient more complex uh order uh and killing off the ones that uh doesn't work so well. And so laborously you climb up this mountain probable step by step by step. Well, of course it didn't start uh with microbes. There's a mountain probable that starts with chemistry. You've got to climb all the way from simple chemistry to complex chemistry to living chemistry. the chemistry of living matter. Um how do you climb that mountain probable in that prebiotic sense? Uh and is there any way of measuring what would be the elevation up mountain probable? Can we look at a particular complex uh chemical mixture and give it a probability and say how close it has come to to actually forming life.嗯,我认为我们做不到。你看,我认为我们不仅缺乏对生命的定义,我们甚至缺乏对你可能正在多么接近生命的定义。关键何在呢?我们甚至不知道从非生命到生命的路径究竟是一场无缝的复杂性上升过程——始于简单,历经数千万、数亿年变得越来越复杂、越来越复杂,直到突然间你会说:“好吧,我想我们现在会把这个真正复杂的东西称为活的”;抑或它更像是一种相变,比如气体突然燃烧起来,你沿着这条路径前进,它变得越来越复杂,突然间出现了一次跃迁,你会说它就在那个特定节点迸发出了生命。然后,如果我们有一个生命测量仪,能够指明你在这条路径上的位置,说明那次跃迁是否发生,那么派这台测量仪进入宇宙,去寻找其他可能发生过这种跃迁的地方,就会是有价值的。但我们还没走到那个阶段。我们不知道如何制造生命测量仪,因为我们并不知道该如何理解这条路径、生命的门槛,以及什么才构成接近生命。
英文原文
Well, I don't think we can. You see, I think we lack uh not only lack a definition of life, we lack a definition of uh even how close you might be getting to life. And what's the point? We don't even know whether the pathway from non-life to life was just some sort of seamless upward march of complexity. starting out simple over millions and millions of years getting more and more complex more and more complex until suddenly you would say well now I guess we would call this really complex thing living or whether it's more like a phase transition like um a gas bursting into flame that you would uh go along this pathway it would get more and more complex and suddenly there'd be a jump uh and you would say it sprung into life at that particular point and then if we had a life meter that could uh say where you are on that pathway has that jump happened uh then it will be worth sending that meter out into the universe to look for somewhere else where that jump may have occurred but we haven't got to that stage yet. We don't know how to build a life meter because we don't really know how to understand this pathway uh and the threshold of life and what will constitute almost life.暗影生物圈与地外生命的本质
因此,天体生物学家非常喜欢在太阳系外寻找类地行星,这很自然。嗯,但我们知道的最像地球的行星正是地球本身。因此,这就提出了一个问题:如果在类地条件下生命很容易产生,它是否可能在我们这个家园星球上发生过不止一次?我们怎么知道它没有呢?有人真正去寻找过吗?嗯,事实证明,并没有人真正认真对待过生命可能在地球上诞生过许多次这一观点。现在,情况可能是生命在地球上起始了500次,而只有一种生命形式存活到了今天。但我们能绝对确信地球上没有其他生命样本藏在某个已知的生命无法触及的微小生态位中吗?来自40亿年前另一次生命起源的后代,是否有可能今天仍然存在于地球的生物圈中?嗯,这是一个非常具有推测性的想法,有时被称为暗影生物圈:在与我们所知晓和热爱的生物圈并存的、混杂在我们周围的有机体、微生物之中的,可能会有来自另一次起源事件的某些微生物。这不仅会是已知生命之树上的不同分支,而是完全不同的一棵树。嗯,我们该如何分辨呢?如果有这样的东西存在,我们又怎么会知道呢?嗯,我们会发现它们吗?事实证明,当你非常仔细地审视这一点时,答案是否定的。我们很可能根本不会注意到它们。它们可能就在我们周围各处。因此,可能存在第二种生命样本,如果你愿意的话可以说成是外星生命,就在我们鼻子底下,甚至就在我们鼻子里,嗯,而没有人真正下功夫去寻找过。
英文原文
So astrobiologists love looking for earthlike planets beyond the solar system and that's very natural. Uh but the most earthlike planet we know is earth itself. And so that raises the question about whether if life arises readily under earthlike conditions. Might it have happened more than once right here on our home planet? How do we know it didn't? Has anybody actually looked? Uh and it turns out that nobody's really taken very seriously the idea that life could have arisen on Earth many times over. Now it could be that life started 500 times on Earth and only one form of life has survived to the present day. But can we be absolutely sure that there is no other sample of life on Earth hiding somewhere in some uh little niche uh beyond the reach of of known life? Could it be that descendants from a uh another genesis 4 billion years ago uh are still here in Earth's biosphere today? Uh this is um a very speculative idea sometimes called the shadow biosphere that alongside uh the uh biosphere that we know and love uh in intermingled among the organisms the microorganisms uh that are all around us might be some microorganisms from uh another genesis event. this this would be uh not just a different branch on the known tree of life but a different tree entirely. Uh how could we tell how how would we know if such things are out there? Uh would we have spotted them? And it turns out the answer when you look at this very carefully is no. We probably wouldn't have noticed them. They could be there uh all around us. So it could be that there's second sample of life uh alien life if you like uh right under our noses or even in our noses um and nobody has really made an effort to look.现在,人们喜欢提出一种反对意见,那就是一旦某种生命形式开始运转,它就会在某种程度上霸占所有的资源,并改变环境条件以维持自身的存在,而这将不利于任何其他类型有机体的生存。经典的例子就是当生命发现了光合作用,嗯,我不知道,在25亿或30亿年前,嗯,然后它导致了大气中氧气的积聚。我们往往认为氧气是个好东西,对你我来说确实如此。嗯,但它是一种极其强烈的腐蚀性毒物。嗯,当它最初出现时,它威胁要彻底消灭生命。它曾是一种污染物。嗯,全凭生命能够——某些生命能够适应并真正化弊为利,将那种氧气用作能源,嗯,我们今天才处在拥有富氧大气层的境地。但氧气的积聚带来的影响,不仅限于让生命变得更富含能量、更复杂。嗯,例如,它还改变了岩石的性质。把地球和火星对比一下。你看火星,它明显发红,因为那种红色实际上就是铁锈。因此火星没有这种循环机制。它没有板块构造。它没有到处移动的板块。以及改变它的火山——它有火山,但它无法成功循环所有这些元素等等。因此,地球上的生命与驱动地球上生命的循环之间存在着一个反馈回路,并且彼此互相影响。嗯,关于你多久会遇到一颗非常像地球的行星,这是非常不确定的,地球拥有这些交织在一起的生物循环、地质循环和大气循环,它们全部协同运作以相互改变、相互支撑,嗯,而且这样运行不仅持续了一段短暂的时间,而是实打实地持续了数十亿年。因此,这些循环是共同演化而来的。这可能是一套非常特殊的环境条件。正如一本著名书籍的书名所言,它可能是一个“稀有地球”。它可能确实是一个稀有地球。
英文原文
Now there's a a counterargument that people like to make which is that once one form of life gets going it sort of appropriates all the resources and changes the condition conditions uh in order to uh sustain its own existence. that this would act against any the survival of any other type of organism. The classic example is when photosynthesis was discovered by life uh I don't know 2 and a half 3 billion years ago um and then uh it led to the buildup of oxygen in the atmosphere. We tend to think of oxygen as a good thing and it is for you and me. Um but it's a terrible corrosive poison. Uh and when it first appeared uh it threatened to wipe out life totally. It was a pollutant. Uh and it was only that life was able to some life was able to adapt and actually turn a sin into a virtue and use that oxygen as an energy source uh that we are where we are today with an oxygenrich atmosphere. But the buildup of oxygen has uh uh led to more than allowing life to become more energy rich, more complex. Um it's also changed the nature of rocks, for example. Contrast the Earth with Mars. You look at Mars, it's noticeably red because that red is really rust. And so Mars doesn't have this recycling mechanism. It doesn't have plate tectonics. It doesn't have plates that move around. and uh volcanoes that change it has volcanoes but it doesn't uh manage to to cycle all of these elements and so on. So there's a feedback loop between the life on earth and the cycles that drive uh life on earth uh and and each affects the other. Um it's very unclear uh how often you would come across a a planet quite like the earth which has these interlocking cycles the biological and the geological and the atmospheric all working together to to change each other and sustain each other uh which is done not just uh for a short duration but over literally over billions of years. So this these cycles have co-evolved. It may be a very special set of circumstances. It may be that it is a rare earth to use uh a a title of a famous book. It could be as a rare earth.而且我认为大多数人在寻找外星生物时,脑海中的概念都是血肉之躯的有机体,你知道,就像你在另一颗星球上可能会发现的外形怪异的动物。但是非常明确的是,如果那里存在技术文明,一旦他们达到了我们的发展水平,他们很快就会开始将他们的智力重活外包给……我更愿意称之为设计系统。“人工的”是一个糟糕的词。我认为它是设计出来的智能。我们拥有达尔文式的智能,非常缓慢,耗费了数十亿年才走到这一步。而设计智能可以非常迅速,一旦你把设计原则嵌入到设计智能中,一旦人工智能获得了下一代的设计原则等等,它就会非常迅速地腾飞。我可以想象在不久的将来会出现一种人工智能系统,它会使用来自活生物体的组件,你知道,融入神经组织——人们甚至现在就还在这么做,将它们融入到某个更大的系统中去——以至于我们将会失去这种“它是活的还是非活的”的界限,嗯,而它实际上仅仅归结为它是被设计的吗,以及它是否正在设计下一代。
英文原文
And I think most people have the idea of searching for alien beings as f flesh and blood uh organisms, you know, weird looking animals that you might find on another planet. But it it's very clear that if there are techn technological civilizations out there uh that they would very soon um if they got to our level of development uh begin to outsource their intellectual heavy lifting uh to uh I I prefer call them design systems. It's not artificial is a bad term. I I think of it as designed intelligence. We've got Darwinian intelligence very slow. It's taken billions of years to get to this point. And then designed intelligence can be very rapid and once you embed the design principles in the designed intelligence once AI gets the uh design principles for the next generation and so on uh it it very rapidly uh takes off. I can imagine an AI system in the not too distant future that would use uh components from living organisms uh you know from uh neural tissue uh being incorporated and people are still doing this even now incorporating those uh into some larger system and that we're we're going to lose this distinction between is it living is it non-living um uh and it really just boils down to is it designed and uh and is is it designing the next generation等等。所以,如果我们真能接触到外星人——虽然我持相当怀疑的态度,但如果我们真的做到了,绝大多数可能不是某种好莱坞式的血肉之躯,而是某种我们或许可以称之为 AI 的东西,但我们其实缺乏一个词汇来定义这种超智能、经过多代设计的系统可能究竟是什么。不过很明显,仅从我们当前的发展路径来看,这个实体显然将拥有神一般的特征,我们将面对的可能是某种远远超出我们理解水平的存在。如果我们把 AI 与量子计算相结合,事情就会变得极其有趣且意义深远。于是我们有了 QAI,即量子人工智能(Quantum Artificial Intelligence),或者像弗兰克·维尔切克(Frank Wilczek)所称的“量子智能”(quintelligence)。到了那时,一切常理都不再适用了,因为我们面对的不再仅是一个能探索我们在自身大脑中探索的所有可能性的实体,而是一个能探索所有可能的量子替代方案、所有可能世界的实体。因此,我们面对的是某种具有智能、意识或某种形态的行动主体(agent),它所拥有的可能性范围、体验以及可运作的处理过程,都比我们所拥有的无限广阔。而如果我们接触到的外星文明已经延续了五亿年或更久,它绝大概率将被这些神一般、全然神秘且令人敬畏的实体所主导。
英文原文
and so on. So, we're if if we ever do contact ET,and I'm pretty skeptical, but if we ever do it, uh
it's overwhelmingly likely not to be some sort of
uh you know, Hollywood style flesh and
blood being, but it's going to be some
uh something we might want to call AI, but we we
we lack a term for what this super intelligent
uh multi-generation designed uh system might
be. But it's clear that the just from the way
we're going, it's clear that this entity would
have godlike uh uh features that we would be
dealing with something which would uh be probably
well beyond our level of understanding. And if we
combine AI with quantum computing, so it's where
it gets really interesting and really profound. So
we got Q AI, quantum artificial intelligence
or quintelligence as Frank Wilchek calls it.
uh then all bets are off because now we're dealing
with an entity that can explore not only uh all of
the possibilities that we can explore in our own
minds um but all possible quantum alternatives
all possible worlds. So we're dealing with some
sort of uh entity that intelligent or conscious
or it might be an agent of some sort which has
an infinitely greater uh range of possibilities
and experiences and uh processes that can it can
operate than we do. And if we're dealing with the
ET that has civilization that's been going for 500
million years or something, it's overwhelmingly
likely it's going to be dominated by the these
godlike totally uh mysterious awesome entities.
第 4 章:金发女孩之谜:宇宙是为生命微调的吗?
现在换上我作为物理学家的身份,审视整个宇宙,物理定律的本质令我深感震撼——宇宙是以非常精确的数学方式井然有序地运作的,而且这些基础定律不仅优美、强大,代表着使宇宙能够如此高效运转的数学关系,它们还与生命的存在相容。这一课题通常被称为“人择原理”(anthropic principle)。这是一个很糟糕的名称。但它的基本含义如下:如果你考察物理学的各项定律以及宇宙的初始条件(即大爆炸发生的方式),然后假设我们做一点微调——比如,假设你想让所有电子稍微变重一点,或者让弱核力稍微变弱一点,你能通过对这些参量的微调依然使生命得以存在吗?结果表明答案是否定的。某些物理定律极其敏感,最微小的变动都会扼杀生命的希望。这些变动从字面上讲将是致命的。
英文原文
Chapter 4. The Goldilocks Enigma.Is the universe fine-tuned for life?
So now putting on my uh physicist hat and looking
at the universe as a whole uh I'm struck by the
nature of physical laws uh the fact that the
universe is ordered in a very precise mathematical
manner uh and that these underlying laws are
not only beautiful and powerful and represent
uh uh mathematical relationships uh that um
uh enable the universe to run uh in such an
efficient way, but they're also consistent
with the existence of life. And so this is
uh a subject often goes under the name of the
anthropic principle. is a very bad name. But
what it basically means is is the following that
if you take uh the various laws of physics and the
initial conditions for the universe, the way the
big bang went bang uh and if you say well suppose
we change something a little bit uh say you you
wanted to make all electrons a little bit heavier
uh or the weak nuclear force a little bit weaker,
you know, can you could you muck around with those
things in such a way as to still have life? And
it turns out that the answer is no. That some of
the laws of physics are so exquisitly sensitive
that the tiniest change would wreck the prospects
of life. Those changes would be literally lethal.
显然,我们无法进行真实的实验,但我们可以进行数学思想实验。我们可以计算出,如果引力稍微变强,或者电力稍微变弱之类,世界会发生怎样的变化。当你这样做时,就会发现一些相当微小的改变都会扼杀生命的可能。例如,它可能会阻止复杂原子核的形成。你最终得到的可能是一个完全由中子构成的宇宙,或者完全只有氢而没有碳这种赋予生命的元素。因此,你可以审视所有这些情况并得出结论:宇宙中、整个宇宙中的自然法则似乎是——这里的术语开始带有些许争议——似乎是为生命微调的。人们谈论所谓的微调论证(fine-tuning argument)。微调并不一定意味着存在一位故意选取这些数值以确保生命诞生的设计者;但它的确意味着,如果那些数值稍微有所不同,就不会有任何生命存在,我们也就不会坐在这里进行这场对话了。
英文原文
Now, obviously, we can't do the real experiment,but we can do the mathematical experiment. We can
figure out how would the world change gravity was
a bit stronger or if um the uh electrical forces
were a bit weaker or something. And and when you
do that, you find that some rather small changes
would wreck the chances of life. Uh for example,
it might prevent uh complex nuclei from forming.
You might end up with a universe that consists
entirely of neutrons or entirely of just hydrogen
with no carbon, the life-giving element. Uh so you
can look at all those things and conclude that
uh the the universe uh that the laws of nature
in the universe as a whole seem to be and this
is where it gets uh the terminology gets a bit
controversial seem to be fine-tuned for life.
People talk about the fine-tuning argument.
Now finetuning doesn't necessarily mean uh that
there was a designer who deliberately picked those
values in order that there should be life. Uh, but
what it does mean is that if those numbers were a
bit different, there wouldn't be any life and we
wouldn't be here having this conversation.
那么,我们该如何理解这一点呢?我称之为“金发女孩之谜”(Goldilocks enigma)——宇宙看起来对生命而言“恰到好处”。因此,对于金发女孩现象,我们实际上有三种可能的解释。一种是:纯属巧合,事情恰好就是这样发生的,反正生命也没有任何特殊之处。另一种是:存在一位设计者或上帝创造了宇宙,并为了生命的诞生对其进行了微调。你还可以采取的另一种回应是多重宇宙解释:宇宙之所以对生命恰到好处,是因为宇宙不仅只有一个。存在无数个宇宙,并且起初带有一种随机性。大爆炸发生时,很多爆炸散落在空间和时间各处,每一个都有自己的一套定律。于是在其中一些宇宙里,引力会稍微强一些;在另一些宇宙里,电子会稍微重一些,等等。而且在绝大多数宇宙中,不会存在生命。因此并没有人在那里哀叹它们不是金发女孩宇宙。但在这里和那里,仅仅依据几率法则,你会发现存在一个金发女孩宇宙;而在那个宇宙中,将会产生像我们这样活生生的生物,并反思这一切到底意味着什么。所以,这三种观点目前都存在,相关讨论也一直在进行。归根结底,在现阶段这纯粹是一个个人选择的问题。
英文原文
So, what are we to make of this? I call this theGoldilocks enigma that the universe looks like
it's just right for life. So, we have really
three possible explanations for Goldilocks.
We've got it's just a fluke. It happened that way
and there's nothing special about life anyway.
There was a designer or god who sort of made
the universe, fine-tuned it in order that life
should arise. And the other response that you
can take to this is the multiverse explanation
that the universe is just right for life because
it isn't just one universe. There's an infinite
number of them and it starts out sort of random.
Uh that the big bangs, lots of bangs going off
scattered throughout space and time and each one
comes with its own set of laws. And so in some of
these universes, gravity will be a bit stronger.
In some the electrons will be a bit heavier and
so on. Um, and in the vast vast majority of those
universes, there won't be life. And so there's no
one around to bemen the fact that they're not
Goldilocks universes. But here and there, uh,
just by the laws of chance, you're going to find,
uh, that there will be a Goldilocks universe, and
in that universe, there will be living creatures
like ourselves who arise and reflect on what does
it all mean? And so those three ideas are out
there, and that discussion continues to take
place. And really it boils down to at this stage
a matter of personal choice.
但实际上还有戴维斯的第四种途径。我一直以来谈论物理定律的方式都是传统的视角,即视其为某种固定不变的数学关系。我说过它们在宇宙起源伊始就被烙印其上,就像制造者的标记一样。换句话说,定律是固定的。但你知道,这也许是一种过于简单化的看待方式。这是自牛顿以来物理学家看待定律的方式——将其视作不可改变、永恒且普适的数学关系。但也许我们应该从“灵活定律”(flexi laws)或某种更具延展性的事物角度来思考。这正是事情变得相当微妙之处,因为生命和心灵的涌现是否存在某种方式,可以在某种因果层面上与催生它们的定律本质联系起来?像我们这样的观察者,与促成观察者涌现的定律之间,是否存在某种反馈循环?你会想:如果定律是固定的,那简直是荒谬的。但早些时候我们用过一个很粗略的类比,我们谈到了地球,谈到了地球上的生命——反馈循环,即我们地球这颗行星的物理属性与上面的生命紧密相连。因此,生命的存在影响了地球的运转方式等等。那么是否存在某种宇宙反馈循环,使得生命的存在影响了随后孕育出生命的定律呢?乍看之下,你会认为这完全不可能。但实际上存在一个漏洞。这个漏洞源于量子力学、量子物理学。
英文原文
But there is actuallyDavis's fourth way. I've been talking about the
laws of physics in the traditional way of sort of
fixed immutable uh mathematical relationships.
I said stamped on the origin of the universe,
you know, at the outset like the maker's mark. So
in other words, the laws are fix. But you know,
maybe that's a simplistic way of looking at it.
It's the way that physicists have looked at the
laws ever since Newton as uh im immutable eternal
universal mathematical relationships. But maybe
uh we should think in terms of flexi laws or
something that's a bit more malleable. Uh this
is where it does get rather subtle because um I
if it's uh is there any way in which the emergence
of life and mind can be connected in some way
some causal way with the nature of the laws that
gives rise to them? Is there like a feedback loop
between observers like ourselves and the laws that
uh enable the emergence of observers? You think
well if the laws are fix that's ridiculous. Um but
earlier we I a very rough analogy we were talking
about the earth the way that life on earth um uh
the feedback loops uh the the physical nature of
our planet of planet earth and the life upon it
uh are connected together. So the uh existence of
life affects the way the earth behaves and so on.
Is there some sort of cosmic feedback loop? So the
existence of life affects the laws that then give
rise to that life. And at first sight you would
think that that's completely impossible. But
actually there is a loophole. And that loophole
arises in in quantum mechanics, quantum physics.
其原因在于,我之前一直说按照传统观点定律在最初就是固定的。但实际上,因为量子力学建立在不确定性的概念之上。人们都听过海森堡测不准原理,它的含义是:即使你现在极其精确地设定了一个量子系统、一个处于某种状态的原子,你也不能确定它在 1 秒后会是怎样的;但这种不确定性同样可以回溯至过去。认为在大爆炸的宇宙起源与今日世界之间存在一条固定历史的假设,本身就是一种谬误。大约 30 年前,物理学家约翰·惠勒(John Wheeler)发现可以进行一种被称为“延迟选择实验”(delayed choice experiment)的实验,在该实验中,你可以在当下决定它在过去本应是怎样的状态。在量子力学中,像光子这样的存在可以根据具体情境被描述为粒子,也可以被描述为波。而身为实验者的你可以做出选择:我可以做一个揭示其波动性的实验,或者我可以做一个揭示其粒子性的实验。但事实表明,如果你问这样一个问题:“那么在 1 纳秒之前,甚至在你做出选择之前,它究竟是粒子还是波?”它原本的状态取决于你在当下时刻所决定的状态,因为量子的模糊性吞噬了过去。
英文原文
Um and the reason is uh because I've been sayingwell the laws are uh the traditional way is that
the laws are fixed at the beginning. Um but
actually because uh quantum mechanics is based
on the notion of uncertainty. People have heard
of Heisenberg's uncertainty principle and what
it means is even if you set up very precisely
a quantum system an atom in a certain state now
you can't be certain how it's going to be in 1
second time but that uncertainty goes back in
time as well it's a fallacy to suppose that
there is a fixed history connecting the big
bang origin of the universe with the world today
and about 30 years ago John Wheeler the physicist
discovered that you could do an experiment called
the delayed choice exper experiment in which you
decide now what it shall have been in the past.
So in quantum mechanics something like a photon
can be described as a particle or it could be
described as a wave depending on the circumstances
and you the experimentter can choose. I will do an
experiment that will disclose the wavelike nature
or I shall do an experiment that will disclose
the particle-like nature. But it turns out if
you ask the question, well, was it a particle or
a wave one nancond ago, even before your choice,
it would have been what you decided in the present
moment because quantum fuzziness engulfs the past.
现在,你并不是把信息发送回过去。你并没有改变过去。过去是模糊暧昧的。我们对过去了解某些事情,但并非全知。所以,如果我们今天所做的事情消除了过去的某种歧义,这并非逆向因果,但这确实构成了现在发生的事情与过去发生的事情相联系的一种方式。在量子物理学中毫无疑问就是这种情况。你可以在当下决定现实在过去本应是什么样子。我们将这一点从“它是波还是粒子”推广到“物理定律本身是否也是这种量子图景的一部分”?是这种物理定律,还是那种物理定律?现在我们开始看到存在一种纽带,即生命与心灵的存在可以通过定律的灵活性以及这种量子逆反效应,以这种非常微妙的方式,对其宇宙中所涌现的定律本质获得某种调控。因此,这非常容易被误解。我并不是说我们现在改变了过去以确保我们自身的存在。但是存在一种自洽性。存在一种在量子物理学中起作用的反馈循环。
英文原文
Now, you're not sending information back intime. You're not changing the past. The past is
ambiguous. So, we know some things about the past,
but not everything. So if something we do today
resolves an ambiguity in the past, then it's not
backward causation, but it is a way in which what
happens now uh is linked to what happens in the
past. No doubt that this is the case in quantum
physics. You you can decide now what reality shall
have been in the past. We extend that from was
it a wave, was it a particle to are the laws of
physics themselves part of this quantum landscape?
Uh was it this law of physics? Was it that law of
physics? Now we begin to see that there's a nexus,
a way in which the existence of life and mind
[snorts] can gain some sort of patches over
the nature of the laws that have emerged in the
universe by having flexibility in the laws and
having this sort of quantum retroaction effect
uh and uh in this very subtle way. So it's it's
very easy to misunderstand what I'm saying. I'm
not saying that we now have changed the past
to ensure our own existence. Um, but there is a
consistency. There's a feedback loop that operates
in in quantum physics.
这就是第四种方式。所以你现在有了:纯属巧合;上帝所为;存在无数个宇宙而生命极其罕见但会在某处出现;抑或存在一种方式,使生命与宇宙构成一个共同存在循环的一部分。而且我应该说明,这个想法并不是我的独创。这是我所青睐的观点。它是物理学家约翰·惠勒多年前所青睐的想法,对我产生了巨大影响。他是提出延迟选择实验的人,而那正是他想法的跳板——即宇宙中的参与者,也就是拥有心灵、具备选择能力、并且能够在量子物理中做实验和进行测量的存在,可以成为整个存在画卷的一部分。我觉得这非常引人入胜。
英文原文
So that's number four. Soyou've now got it's just an accident. God did it.
There's an infinite number of universes with life
very rare but popping up somewhere. Or there's a
way in which life and the universe form part of
a common existence loop. And that idea, I should
say, is not my idea. It's the one I favor. It was
the idea that John Wheeler, the physicist, uh,
favored uh, many years ago. Was a big influence
on me. And he was the one who came up with this
delay choice experiment. And it was sort of a
springboard for his idea that participants in the
universe that is beings who have minds and choices
and can do experiments and make measurements uh
in quantum physics could be part of the whole
existence story. And I find that very appealing.
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