sponsored links
TED2014

Allan Adams: The discovery that could rewrite physics

アラン・アダムズ: 物理学を書き換えうる発見

March 18, 2014

2014年3月17日、物理学者のグループが身震いのするような発見を発表しました。ビッグバンにつながる宇宙のインフレーション理論を証明する「動かぬ」証拠となるデータを得たのです。物理学者ではない私たちにとって、それは何を意味するのでしょうか。TEDの依頼で、急遽、アラン・アダムズがこの結果について簡単な説明をします。イラストはxkcdのランダル・モンローです。

Allan Adams - Theoretical physicist
Allan Adams is a theoretical physicist working at the intersection of fluid dynamics, quantum field theory and string theory. Full bio

sponsored links
Double-click the English subtitles below to play the video.
If you look deep into the night sky,
夜空を眺めると
00:12
you see stars,
星が見えます
00:16
and if you look further, you see more stars,
ずっと遠くを観察すると
もっと星が見え
00:17
and further, galaxies, and
further, more galaxies.
更に遠くを観察すると銀河が
いくつも見えます
00:20
But if you keep looking further and further,
更にもっと遠くを見て行くと
00:22
eventually you see nothing for a long while,
暫くずっと何もない状態が続き
00:26
and then finally you see a
faint, fading afterglow,
最後に かすかに消え行く
残光が見えます
00:29
and it's the afterglow of the Big Bang.
ビッグバンの残光です
00:34
Now, the Big Bang was an era in the early universe
ビッグバンの瞬間―宇宙最初期には
00:37
when everything we see in the night sky
今夜空で見えてるものの全てが
00:39
was condensed into an incredibly small,
恐ろしく小さく凝縮され
00:42
incredibly hot, incredibly roiling mass,
超高密度 超高温度の
熱い火の玉でした
00:44
and from it sprung everything we see.
私たちの周りの全ては
そこから始まったのです
00:48
Now, we've mapped that afterglow
さて その残光は非常に精密に
マッピング観測されています
00:51
with great precision,
さて その残光は非常に精密に
マッピング観測されています
00:54
and when I say we, I mean people who aren't me.
観測したのは私ではないのですが
00:56
We've mapped the afterglow
残光は厳格に細かく
00:58
with spectacular precision,
観測されています
00:59
and one of the shocks about it
その結果で驚くことの1つは
01:01
is that it's almost completely uniform.
140億光年四方
ほとんど完全に均質で
01:02
Fourteen billion light years that way
140億光年四方
ほとんど完全に均質で
01:05
and 14 billion light years that way,
140億光年四方
ほとんど完全に均質で
01:07
it's the same temperature.
同じ温度なことです
01:09
Now it's been 14 billion years
ビッグバンから
140億年が経った今では
01:10
since that Big Bang,
ビッグバンから
140億年が経った今では
01:14
and so it's got faint and cold.
微かに冷たくなり
01:16
It's now 2.7 degrees.
絶対温度2.7度です
01:18
But it's not exactly 2.7 degrees.
完全に2.7Kというわけでなく
01:20
It's only 2.7 degrees to about
10万分の1程度ムラがあります
01:23
10 parts in a million.
10万分の1程度ムラがあります
01:25
Over here, it's a little hotter,
少し熱い所があったり
01:27
and over there, it's a little cooler,
少し冷たい所があったりします
01:28
and that's incredibly important
to everyone in this room,
ここにいる皆さんにとって
これは大きな意味があります
01:30
because where it was a little hotter,
なぜなら熱い所は
01:33
there was a little more stuff,
何かがあり
01:34
and where there was a little more stuff,
何かある所にこそ
01:36
we have galaxies and clusters of galaxies
銀河や銀河団や
01:38
and superclusters
超銀河団や
01:40
and all the structure you see in the cosmos.
宇宙で見られる
全てのものがあるからです
01:41
And those small, little, inhomogeneities,
5万分の1の割合で存在する
こうした小さな不均質性は
01:44
20 parts in a million,
5万分の1の割合で存在する
こうした小さな不均質性は
01:47
those were formed by quantum mechanical wiggles
量子的ゆらぎが生み出したもので
01:49
in that early universe that were stretched
宇宙初期
01:52
across the size of the entire cosmos.
宇宙全体に広がりました
01:54
That is spectacular,
壮大なものです
01:56
and that's not what they found on Monday;
3月17日の発見はそれではなく
01:58
what they found on Monday is cooler.
もっとクールなことで
01:59
So here's what they found on Monday:
これがそうです
02:01
Imagine you take a bell,
鐘を考えてみて下さい
02:04
and you whack the bell with a hammer.
金槌で鐘を叩くと
02:07
What happens? It rings.
どうなります?音が鳴りますね
02:09
But if you wait, that ringing fades
暫くすると その音は
02:10
and fades and fades
どんどん小さくなって行き
02:13
until you don't notice it anymore.
聞こえなくなります
02:14
Now, that early universe was incredibly dense,
初期の宇宙は非常に密度が高く
02:16
like a metal, way denser,
金属よりも超高密度で
02:19
and if you hit it, it would ring,
叩くと音が出る程だったでしょう
02:21
but the thing ringing would be
音を出すのものは
02:23
the structure of space-time itself,
時空そのものの構造で
02:25
and the hammer would be quantum mechanics.
金槌は量子力学です
02:27
What they found on Monday
3月17日の発見は
02:30
was evidence of the ringing
宇宙初期の時空が鳴り響く音を
証明するもので
02:32
of the space-time of the early universe,
宇宙初期の時空が鳴り響く音を
証明するもので
02:34
what we call gravitational waves
「重力波」と呼ばれ
02:37
from the fundamental era,
宇宙の原始時代からのものです
02:39
and here's how they found it.
発見の経緯はこうです
02:40
Those waves have long since faded.
重力波は とうの昔に
弱まっていますから
02:42
If you go for a walk,
私たちが散歩に出かけ
02:44
you don't wiggle.
ブルブル震える事はありませんが
02:46
Those gravitational waves in the structure of space
宇宙の構造の中で重力波は
02:47
are totally invisible for all practical purposes.
事実上 全く無視して構わないものです
02:50
But early on, when the universe was making
しかし 宇宙がまだ最後の
02:53
that last afterglow,
残光を発している初期には
02:56
the gravitational waves
重力波は
02:58
put little twists in the structure
私たちが見る光の構造に
03:00
of the light that we see.
微かなパターンを残しました
03:03
So by looking at the night sky deeper and deeper --
この研究チームは夜空をよく見て—
03:04
in fact, these guys spent
three years on the South Pole
実際 南極で3年間費やして
03:07
looking straight up through the coldest, clearest,
何処にもないような冷たく
澄み切った空気の中で
03:10
cleanest air they possibly could find
何処にもないような冷たく
澄み切った空気の中で
03:12
looking deep into the night sky and studying
空を見上げ あの残光を観察し
03:15
that glow and looking for the faint twists
微かなパターンとなった
03:17
which are the symbol, the signal,
重力波のシグナル—
03:20
of gravitational waves,
初期の宇宙が鳴る音を見つけ
03:23
the ringing of the early universe.
初期の宇宙が鳴る音を見つけ
03:25
And on Monday, they announced
3月17日 この発見を
03:27
that they had found it.
発表したのです
03:29
And the thing that's so spectacular about that to me
これがすごいのは
ビッグバンからの波—
03:31
is not just the ringing, though that is awesome.
というだけでなく
勿論それはすごいのですが—
03:33
The thing that's totally amazing,
本当にすごいのは
03:36
the reason I'm on this stage, is because
これを言う為に
今日ここに来たのですが—
03:37
what that tells us is something
deep about the early universe.
このことは 初期の宇宙にとって
深い意味があるのです
03:39
It tells us that we
つまり これが示す事は
03:43
and everything we see around us
私たちの宇宙は
03:44
are basically one large bubble --
1つの大きな泡のようなもの
ということです
03:46
and this is the idea of inflation—
これこそ インフレーション理論です
03:49
one large bubble surrounded by something else.
何かに囲まれた大きな泡なのです
03:50
This isn't conclusive evidence for inflation,
決定的証拠ではありませんが
03:54
but anything that isn't inflation that explains this
インフレーション以外で
これを説明しようとしても
03:56
will look the same.
結局同じことになるでしょう
03:59
This is a theory, an idea,
これは長い間1つの理論
アイデアであって
04:00
that has been around for a while,
これは長い間1つの理論
アイデアであって
04:02
and we never thought we we'd really see it.
重力波は検知される事はないだろう
と思われていました
04:03
For good reasons, we thought we'd never see
こんな有力な証拠が
見られるとは思わなかったのです
04:05
killer evidence, and this is killer evidence.
こんな有力な証拠が
見られるとは思わなかったのです
04:06
But the really crazy idea
信じられないような事は
04:09
is that our bubble is just one bubble
私たちの宇宙は 様々なものが
渦巻く中の1つの泡にすぎないのです
04:11
in a much larger, roiling pot of universal stuff.
私たちの宇宙は 様々なものが
渦巻く中の1つの泡にすぎないのです
04:14
We're never going to see the stuff outside,
私たちの宇宙以外は
見る事はなくても
04:18
but by going to the South Pole
and spending three years
南極で3年暮らし
04:20
looking at the detailed structure of the night sky,
夜空の構造を詳細に観察すると
04:23
we can figure out
私たちはそんな宇宙の中に
居るんだと実感できるのです
04:25
that we're probably in a universe
that looks kind of like that.
私たちはそんな宇宙の中に
居るんだと実感できるのです
04:27
And that amazes me.
本当に驚かされます
04:30
Thanks a lot.
ありがとう
04:33
(Applause)
(拍手)
04:34
Translator:Reiko O Bovee
Reviewer:Yuko Yoshida

sponsored links

Allan Adams - Theoretical physicist
Allan Adams is a theoretical physicist working at the intersection of fluid dynamics, quantum field theory and string theory.

Why you should listen

Allan Adams is a theoretical physicist working at the intersection of fluid dynamics, quantum field theory and string theory. His research in theoretical physics focuses on string theory both as a model of quantum gravity and as a strong-coupling description of non-gravitational systems.

Like water, string theory enjoys many distinct phases in which the low-energy phenomena take qualitatively different forms. In its most familiar phases, string theory reduces to a perturbative theory of quantum gravity. These phases are useful for studying, for example, the resolution of singularities in classical gravity, or the set of possibilities for the geometry and fields of spacetime. Along these lines, Adams is particularly interested in microscopic quantization of flux vacua, and in the search for constraints on low-energy physics derived from consistency of the stringy UV completion.

In other phases, when the gravitational interactions become strong and a smooth spacetime geometry ceases to be a good approximation, a more convenient description of string theory may be given in terms of a weakly-coupled non-gravitational quantum field theory. Remarkably, these two descriptions—with and without gravity—appear to be completely equivalent, with one remaining weakly-coupled when its dual is strongly interacting. This equivalence, known as gauge-gravity duality, allows us to study strongly-coupled string and quantum field theories by studying perturbative features of their weakly-coupled duals. Gauge-gravity duals have already led to interesting predictions for the quark-gluon plasma studied at RHIC. A major focus of Adams's present research is to use such dualities to find weakly-coupled descriptions of strongly-interacting condensed matter systems which can be realized in the lab.
sponsored links

If you need translations, you can install "Google Translate" extension into your Chrome Browser.
Furthermore, you can change playback rate by installing "Video Speed Controller" extension.

Data provided by TED.

This website is owned and operated by Tokyo English Network.
The developer's blog is here.