物理學家解釋為何人類的存在近乎不可能 - Brian Cox 考克斯

there's only one interesting question in

philosophy what does it mean to live a

finite fragile life in an infinite

Eternal Universe 2 trillion 2,000

billion galaxies there aren't any other

worlds where this happened we've seen no

evidence of any civilizations out there

beyond Earth and that's a surprise it's

the only place where meaning exists

potentially in a galaxy of 400 billion

Sons

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I mean in the piece of the universe we

can see uh there are something like

roughly two trillion galaxies 2 trillion

2,000 billion galaxies and each Galaxy

is let's say around the size of the

Milky Way some are bigger some are

smaller but the Milky Way has 400

billion stars in it takes light over

100,000 years to cross a Galaxy and

there are two trillion of them in the

piece of the universe we can see and

we're very sure that that piece that we

can see is a small bit of what may be an

infinite universe beyond we don't know

actually and I always say you know don't

get worried about that because nobody

can picture it it is impossible to

visualize the Scale of the Universe

there's only one interesting question in

philosophy the interesting question is

what does it mean to live a finite

fragile life in an infinite Eternal

Universe it's a good question what does

it mean to live a finite fragile life

life in an infinite Eternal universe and

um I think the

answer is sort of paradoxically whilst

we are definitely physically

insignificant I've just said you know

the Earth is one planet around one star

amongst 400 billion stars in one Galaxy

amongst two trillion galaxies in a small

patch of the universe right so we're

definitely small we can't argue with

that we just F of dust but if you think

about what we are so everybody me and

you everybody

we're we're just collections of atoms

right some of them are as old as time

pretty much and some of them were the

other ones everything else other than

the hydrogen in our bodies was made in

Stars right so so we we all cooked over

billions of years and we're in this

pattern that can

think so suddenly as the great Carl Sean

said you have a means by which the

universe understands and explores itself

which is us and that sounds unlikely

when you put it like that

that you can have a few things that were

cooked in the hearts of stars you stick

them together in a pattern and suddenly

has some ideas and starts writing music

and and art and thing that's that's

quite difficult to comprehend right but

that what that happened here we know

that because we sat here having a

conversation and so the question then

becomes well under how many other worlds

did that happen and that's where I think

the value can come in because uh it's a

reasonable guess and it's just a guess

right but it's reason you can make the

argument that there aren't any other

worlds where this happened certainly in

our galaxy so it could be this planet

not withstanding its physical

insignificance is the only place where

anything thinks right for millions of

light years in every direction and

suddenly therefore you end up

considering this planet as being the

most valuable place in the local

Universe not withstanding the fact that

it's small and that idea it is not just

a complete random guess by the way we've

had a bit of a look we astronomers have

pointed radio telescopes up at the stars

for a while 50 years on more now and

heard nothing we've seen no evidence of

any civilizations out there beyond Earth

and that's a surprise there's a

reasonably plausible explanation for

that which is biology which is that if

you look at the history of life on Earth

then you see that uh life began pretty

much as soon as it could here on Earth

we we have evidence there was life 3.8

billion years ago something like that

and the Earth's 4 and a half billion

years old so pretty much pretty quick in

geological time you get life but then if

you if you talk about Advanced life

complex life multicellular life then

there's no evidence at all Beyond back

Beyond a billion years actually really

in the fossil record 650 million years

ago or something you start seeing the

first evidence of complex creatures so

that means that on on this planet it

took over 3 billion years to go from

single cell life to anything more

complex than a single cell and then

another half a billion years or so to go

from the multicellular things to a

civilization so it's it's three and a

half to four billion years it's a third

of the age of the universe that is a

really long time if you say that's an

unbroken chain of life on a little piece

of rock in a violent universe and that

chain was not cut for 4 billion years in

order to get us and that might be a big

ass right we live in a really violent

universe but you look at the Milky Way

and you look at that Ark of stars across

the sky 400 billion Suns all the all

there will be up there at best is

slime just slime nothing right and and I

think that's a reasonable guess that's

my that's where I start from I mean I

wouldn't be surprised if that's wrong

then you go okay good well

that but at the moment it looks like

there isn't anything else other than

slime we haven't even discovered Slime

by the way yet we're still in a position

where we've not seen anything not even a

single cell on mars or you know the

moons of Jupiter or somewhere like that

so at the moment we are alone as far as

we can tell you know 65 million years

ago or so um the dinosaurs were pretty

much wiped out and that left a little

evolutionary Niche for a little thing

shrew like mammal type thing and and

ultimately that's why we're here if if

that hadn't hit and wiped out cleared

the way we wouldn't be here you probably

wouldn't have a civilization you guess

and so you know there would be none of

the things that we just take for granted

in the potentially the Milky Way galaxy

so if we're the only civilization in the

Galaxy then it's I think it's pretty

likely that if that Comet hadn't hit 65

million years ago and wiped out

dinosaurs there wouldn't be any

civilizations in the G galxy so nobody

nothing could know anything you so none

of this knowledge would exist so that

just shows you how precarious the

position of of civilization and life is

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