TED2008
Patricia Burchat: Shedding light on dark matter
Patricia Burchat heidab tumeainele valgust
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Füüsik Patricia Burchat heidab valgust meie universumi kahele põhiainele: tumeaine ja tumeenergia. Moodustades koos 96% universumist, ei saa neid otseselt mõõta, aga nende mõju on tohutu.
Patricia Burchat - Particle physicist
Patricia Burchat studies the structure and distribution of dark matter and dark energy. These mysterious ingredients can't be measured in conventional ways, yet form a quarter of the mass of our universe. Full bio
Patricia Burchat studies the structure and distribution of dark matter and dark energy. These mysterious ingredients can't be measured in conventional ways, yet form a quarter of the mass of our universe. Full bio
Double-click the English transcript below to play the video.
00:18
As a particle physicist, I study the elementary particles
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Osakeste füüsikuna, uurin ma elementaarosakesi
00:22
and how they interact on the most fundamental level.
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ja seda kuidas nad kõige fundamentaalsemal tasandil suhtlevad
00:25
For most of my research career, I've been using accelerators,
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Enamuse oma teaduskarjäärist olen ma kasutanud kiirendeid,
00:28
such as the electron accelerator at Stanford University, just up the road,
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selliseid nagu elektronkiirendi Stanford'i Ülikoolis, siinsamas kõrval,
00:31
to study things on the smallest scale.
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et uurida asju kõige väiksemal mõõtkaval.
00:34
But more recently, I've been turning my attention
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Hiljuti aga olen ma oma tähelepanu pööranud
00:36
to the universe on the largest scale.
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universumile suurel mõõtkaval.
00:39
Because, as I'll explain to you,
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Sest, nagu ma teile selgitan,
00:41
the questions on the smallest and the largest scale are actually very connected.
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küsimused väiksel ja suurel mõõtkaval on tegelikult väga seotud.
00:45
So I'm going to tell you about our twenty-first-century view of the universe,
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Nüüd ma räägin teile meie 21. sajandi arusaamast universumi kohta,
00:50
what it's made of and what the big questions in the physical sciences are --
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millest see tehtud on ja mis on suured küsimused füüsikateaduses --
00:53
at least some of the big questions.
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vähemalt mõned neist suurtest küsimustest.
00:55
So, recently, we have realized
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Niisis, hiljuti oleme mõistnud
00:58
that the ordinary matter in the universe --
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et tavaline aine universumis --
01:00
and by ordinary matter, I mean you, me,
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ja tavalise aine all mõtlen ma sina, OK, mina,
01:03
the planets, the stars, the galaxies --
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planeedid, tähed, galaktikat --
01:05
the ordinary matter makes up only a few percent
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tavaline aine moodustab ainult mõne protsendi
01:08
of the content of the universe.
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universumi mahust.
01:10
Almost a quarter, or approximately a quarter
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Peaaegu veerand, või ligikaudu veerand
01:13
of the matter in the universe, is stuff that's invisible.
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universumis olevast ainest, on aine mis on nähtamatu.
01:16
By invisible, I mean it doesn't absorb in the electromagnetic spectrum.
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Nähtamatu all pean ma silmas et see ei neeldu elektormagneetilises spektris.
01:20
It doesn't emit in the electromagnetic spectrum. It doesn't reflect.
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See ei kiirga elektromagneetilises spektris. See ei peegelda.
01:23
It doesn't interact with the electromagnetic spectrum,
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See ei mõjuta vastastikuliselt elektromagneetilist spektrit,
01:25
which is what we use to detect things.
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mis on see mida me kasutame asjade avastamiseks.
01:27
It doesn't interact at all. So how do we know it's there?
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See ei tekita üldse mingit vastasmõju. Kuidas me siis teame et see üldse on olemas?
01:30
We know it's there by its gravitational effects.
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Me teame et see on olemas selle gravitatsiooniliste mõjude tõttu.
01:32
In fact, this dark matter dominates
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Tegelikult, see tumeaine domineerib
01:35
the gravitational effects in the universe on a large scale,
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gravitatsioonilisi mõjusid universumi suures mastaabis,
01:38
and I'll be telling you about the evidence for that.
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ja ma räägin teile tõenditest selle kohta.
01:40
What about the rest of the pie?
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Ja kuidas on ülejäänud sektordiagrammiga?
01:42
The rest of the pie is a very mysterious substance called dark energy.
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Ülejäänud sektordiagramm on väga müstiline aine mida kutsutakse tumeenergiaks.
01:46
More about that later, OK.
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Sellest hiljem, OK.
01:48
So for now, let's turn to the evidence for dark matter.
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Nüüd aga pöördume tumeaine tõendite juurde.
01:51
In these galaxies, especially in a spiral galaxy like this,
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Nendes galaktikates, eriti sellises spiraalses galaktikas nagu see,
01:54
most of the mass of the stars is concentrated in the middle of the galaxy.
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on enamus tähtede massi koondunud galaktika keskele.
01:59
This huge mass of all these stars keeps stars in circular orbits in the galaxy.
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Nende tähtede tohutu mass hoiab need tähed galaktikas ümmargusel orbiidil.
02:06
So we have these stars going around in circles like this.
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Nüüd on meil need tähed niimoodi mööda ringi liikumas.
02:09
As you can imagine, even if you know physics, this should be intuitive, OK --
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Nagu te võite ette kujutada, isegi kui te tunnete füüsikat -- see peaks olema intuitiivne, OK --
02:13
that stars that are closer to the mass in the middle will be rotating at a higher speed
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et tähed mis on lähemal kesksele massile keerlevad kiiremini
02:19
than those that are further out here, OK.
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kui need mis on kaugemal, OK.
02:22
So what you would expect is that if you measured the orbital speed of the stars,
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Seega mida võiks oodata kui mõõta tähtede orbitaalset kiirust
02:27
that they should be slower on the edges than on the inside.
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on see et nad on aeglasemad äärtel võrreldes keskmes olevatega.
02:31
In other words, if we measured speed as a function of distance --
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Teisisõnu, kui me mõõdame kiirust kauguse funktsioonina --
02:33
this is the only time I'm going to show a graph, OK --
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see on ainuke kord kui ma näitan graafikut, OK --
02:35
we would expect that it goes down as the distance increases
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võib eeldada et ta läheb alla kauguse suurenedes
02:39
from the center of the galaxy.
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galaktika keskmest.
02:41
When those measurements are made,
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Kui sellised mõõtmised tehakse,
02:42
instead what we find is that the speed is basically constant,
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leiame me selle asemel et kiirus on põhimõtteliselt konstantne,
02:45
as a function of distance.
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kauguse funktsioonina.
02:47
If it's constant, that means that the stars out here
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Kui see on konstantne, tähendab see et need tähed seal
02:50
are feeling the gravitational effects of matter that we do not see.
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tunnetavad meile nähtamatu aine gravitatsioonilisi mõjusid.
02:54
In fact, this galaxy and every other galaxy
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Õigupoolest, see galaktika ja kõik teised galaktikad
02:57
appears to be embedded in a cloud of this invisible dark matter.
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paistavad olevat selle nähtamatu tumeaine pilve sees.
03:02
And this cloud of matter is much more spherical than the galaxy themselves,
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Ja see aine pilv on palju ümmargusem kui galaktikad ise
03:06
and it extends over a much wider range than the galaxy.
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ja ulatub palju kaugemale kui galaktika.
03:10
So we see the galaxy and fixate on that, but it's actually a cloud of dark matter
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Me näeme galaktikat ja keskendume sellele, aga tegelikult on see tumeaine pilv
03:14
that's dominating the structure and the dynamics of this galaxy.
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mis domineerib selle galaktika struktuuri ja dünaamikat.
03:19
Galaxies themselves are not strewn randomly in space;
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Galaktikad ise pole ruumis juhuslikult laiali;
03:22
they tend to cluster.
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nad kalduvad parvedesse kogunema.
03:24
And this is an example of a very, actually, famous cluster, the Coma cluster.
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Ja see on näide ühest eriti kuulsast parvest: "Coma" parvest.
03:27
And there are thousands of galaxies in this cluster.
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Ja selles parves on tuhandeid galaktikaid.
03:30
They're the white, fuzzy, elliptical things here.
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Need on need valged, hägused elliptilised asjad siin.
03:33
So these galaxy clusters -- we take a snapshot now,
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Need galaktikat kogunevad parvedesse -- meie teeme nüüd ülesvõtte,
03:36
we take a snapshot in a decade, it'll look identical.
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teeme ülesvõtte kümnendi pärast -- see näeb välja identne.
03:39
But these galaxies are actually moving at extremely high speeds.
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Aga need galaktikad liiguvad tegelikult äärmuslikult kiiresti.
03:43
They're moving around in this gravitational potential well of this cluster, OK.
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Nad liiguvad ringi selle parve potentsiaalses gravitatsioonilises kaevus, OK.
03:48
So all of these galaxies are moving.
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Kõik need galaktikat liiguvad.
03:50
We can measure the speeds of these galaxies, their orbital velocities,
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Me võime mõõta nende galaktikate kiirusi, nende orbiidi kiirust,
03:54
and figure out how much mass is in this cluster.
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ja välja selgitada kui palju massi on selles parves.
03:56
And again, what we find is that there is much more mass there
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Ja jälle leiame et seal on palju rohkem massi
04:00
than can be accounted for by the galaxies that we see.
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kui võib arvestada nendele nähtavatele galaktikatele.
04:04
Or if we look in other parts of the electromagnetic spectrum,
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Või kui me vaatame elektromagneetilise spektri teisi osi
04:06
we see that there's a lot of gas in this cluster, as well.
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näeme me et selles parves on ka palju gaasi.
04:09
But that cannot account for the mass either.
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Aga ka see ei põhjenda sellist massi.
04:11
In fact, there appears to be about ten times as much mass here
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Õigupoolest, siin paistab olevat kümme korda rohkem massi
04:14
in the form of this invisible or dark matter
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selle nähtamatu tumeaine vormis
04:17
as there is in the ordinary matter, OK.
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kui tavalise aine vormis, OK.
04:21
It would be nice if we could see this dark matter a little bit more directly.
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Oleks kena kui me näeksime seda tumeainet natukene otsesemalt.
04:25
I'm just putting this big, blue blob on there, OK,
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Ma lihtsalt panen selle suure sinise laigu siia, OK,
04:27
to try to remind you that it's there.
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et proovida teile meenutada et see on siin.
04:29
Can we see it more visually? Yes, we can.
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Kas me saame seda kuidagi rohkem visuaalselt näha? Jah, me saame.
04:32
And so let me lead you through how we can do this.
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Las ma juhatan teid läbi selle kuidas me seda teha saame.
04:34
So here's an observer:
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Siin on vaatleja:
04:36
it could be an eye; it could be a telescope.
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see võib olla silm; see võib olla teleskoop.
04:38
And suppose there's a galaxy out here in the universe.
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Ja oletame et on üks galaktika universumis.
04:40
How do we see that galaxy?
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Kuidas me näeme seda galaktikat?
04:42
A ray of light leaves the galaxy and travels through the universe
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Valguskiir lahkub galaktikast ja reisib läbi universumi
04:45
for perhaps billions of years
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võib-olla miljardeid aastaid
04:47
before it enters the telescope or your eye.
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enne kui ta jõuab teleskoopi või teie silma.
04:50
Now, how do we deduce where the galaxy is?
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Nüüd kuidas tuletada galaktika asukoht?
04:53
Well, we deduce it by the direction that the ray is traveling
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No me tuletame selle valguskiire levimise suunast
04:56
as it enters our eye, right?
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silma jõudmise hetkel, eksole?
04:58
We say, the ray of light came this way;
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Me ütleme et valguskiir tuli sellest suunast;
05:00
the galaxy must be there, OK.
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galaktika peab olema seal, OK.
05:02
Now, suppose I put in the middle a cluster of galaxies --
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Nüüd oletame et ma panen keskele galaktikate parve --
05:06
and don't forget the dark matter, OK.
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ja ärge unustage tumeainet, OK.
05:08
Now, if we consider a different ray of light, one going off like this,
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Nüüd kui me kaalume mingit erinevat valguskiirt, eemaldumas sedasi,
05:12
we now need to take into account
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peame me nüüd arvestama
05:14
what Einstein predicted when he developed general relativity.
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sellega mida Einstein ennustas kui ta arendas üldrelatiivsusteooria.
05:17
And that was that the gravitational field, due to mass,
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Ja see on see et gravitatsiooniline väli, massi tõttu,
05:21
will deflect not only the trajectory of particles,
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suunab kõrvale mitte ainult osakeste trajektoori,
05:24
but will deflect light itself.
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vaid suunab kõrvale ka valguse.
05:27
So this light ray will not continue in a straight line,
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Seega see valguskiir ei jätka sirgjoonena,
05:30
but would rather bend and could end up going into our eye.
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vaid pigem paindub ja võib lõpetada teie silmas.
05:34
Where will this observer see the galaxy?
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Kus see vaatleja näeb galaktikat?
05:37
You can respond. Up, right?
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Võite vastata. Üleval, eksole?
05:41
We extrapolate backwards and say the galaxy is up here.
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Me ekstrapoleerime tagurpidi ja ütleme et galaktika on siin üleval.
05:44
Is there any other ray of light
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Kas on veel mõni valguskiir
05:45
that could make into the observer's eye from that galaxy?
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mis võiks jõuda vaatleja silma sellest galaktikast?
05:48
Yes, great. I see people going down like this.
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Jah, suurepärane. Näen inimesi näitavat alla sedamoodi.
05:51
So a ray of light could go down, be bent
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Seega valguskiir võib minna alla, kõverduda
05:53
up into the observer's eye,
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üles vaatleja silma,
05:55
and the observer sees a ray of light here.
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ja vaatleja näeb valguskiirt siin.
05:57
Now, take into account the fact that we live in
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Nüüd võtke arvesse fakti et me elame
05:59
a three-dimensional universe, OK,
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kolmedimensionaalses universumis, OK,
06:01
a three-dimensional space.
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kolmedimensionaalne ruum.
06:03
Are there any other rays of light that could make it into the eye?
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Kas on veel valguskiiri mis võiks jõuda silma?
06:06
Yes! The rays would lie on a -- I'd like to see -- yeah, on a cone.
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Jah! Kiired asuksid -- ma tahaks näha -- jah, koonusel.
06:12
So there's a whole ray of light -- rays of light on a cone --
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Seega on terve valguskiir -- valguskiired koonusel --
06:14
that will all be bent by that cluster
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mida see parv painutab.
06:16
and make it into the observer's eye.
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ja mis jõuavad vaatleja silma.
06:19
If there is a cone of light coming into my eye, what do I see?
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Kui minu silma jõuab valguse koonus, mida ma näen?
06:24
A circle, a ring. It's called an Einstein ring. Einstein predicted that, OK.
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Ringjoont, rõngast. Seda kutsutakse Einstein'i ringiks -- Einstein ennustas seda, OK.
06:28
Now, it will only be a perfect ring if the source, the deflector
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Nüüd see on täiuslik ring kui allikas, deflektor,
06:33
and the eyeball, in this case, are all in a perfectly straight line.
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ja silmamuna, sellel puhul, on kõik ideaalsel sirgjoonel.
06:38
If they're slightly skewed, we'll see a different image.
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Kui nad on natukene viltu, näeme me erinevat pilti.
06:41
Now, you can do an experiment tonight over the reception, OK,
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Nüüd te võite õhtul vastuvõtul teha katse, OK,
06:44
to figure out what that image will look like.
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et välja nuputada milline see pilt välja näeb.
06:47
Because it turns out that there is a kind of lens that we can devise,
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Sest selgub et on selline lääts mida me saame ehitada,
06:51
that has the right shape to produce this kind of effect.
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millel on õige kuju et tekiks selline efekt.
06:54
We call this gravitational lensing.
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Me kutsume seda gravitatsiooniliseks fokuseerimiseks.
06:56
And so, this is your instrument, OK.
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Nii, ja see on see instrument, OK.
06:59
(Laughter).
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(Naer)
07:00
But ignore the top part.
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Aga ignoreerige ülemist osa.
07:03
It's the base that I want you to concentrate, OK.
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Ma tahan et te keskenduksite alusele, OK.
07:06
So, actually, at home, whenever we break a wineglass,
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Ja tegelikult, kodus, kui puruneb veini klaas,
07:08
I save the bottom, take it over to the machine shop.
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hoian ma põhja alles, viin selle meistrile.
07:10
We shave it off, and I have a little gravitational lens, OK.
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Me lõikame selle maha ja mul ongi väikene gravitatsiooniline lääts, OK.
07:14
So it's got the right shape to produce the lensing.
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Niiet sellel on õige kuju et tekitada seda fokuseerimist.
07:16
And so the next thing you need to do in your experiment
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Ja järgmine asi mida tuleb selles eksperimendis teha
07:18
is grab a napkin. I grabbed a piece of graph paper -- I'm a physicist. (Laughter)
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on võtta salvrätik. Ma võtsin tüki millimeeterpaberit, olen ju füüsik. (Naer)
07:22
So, a napkin. Draw a little model galaxy in the middle.
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Nii et siis salvrätik. Joonista väike mudelgalaktika keskele.
07:26
And now put the lens over the galaxy,
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Ja nüüd pane lääts galaktika peale,
07:29
and what you'll find is that you'll see a ring, an Einstein ring.
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ja mis sa näed on ring, Einstein'i ring.
07:32
Now, move the base off to the side,
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Nüüd liiguta põhja ääre poole
07:35
and the ring will split up into arcs, OK.
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ja ring jaguneb kaarteks, OK.
07:38
And you can put it on top of any image.
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Ja seda võib panna ükskõik mis kujutise peale.
07:40
On the graph paper, you can see
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Millimeeterpaberile näeb
07:41
how all the lines on the graph paper have been distorted.
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kuidas kõik jooned millimeeterpaberil on väändunud.
07:43
And again, this is a kind of an accurate model
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Ja jällegi, see on üsnagi täpne mudel
07:46
of what happens with the gravitational lensing.
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sellest mis juhtub gravitatsioonilisel fokusseerimisel.
07:48
OK, so the question is: do we see this in the sky?
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OK, küsimus on: kas me näeme seda taevas?
07:52
Do we see arcs in the sky when we look at, say, a cluster of galaxies?
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Kas me näeme kaari taevas kui me vaatame näiteks galaktikate parvele?
07:56
And the answer is yes.
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Ja vastus on: jah.
07:58
And so, here's an image from the Hubble Space Telescope.
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Nii, ja siin on pilt Hubble'i kosmoseteleskoobilt.
08:00
Many of the images you are seeing
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Paljud pildid mida nägite
08:02
are earlier from the Hubble Space Telescope.
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ennist on Hubble'i kosmoseteleskoobilt.
08:04
Well, first of all, for the golden shape galaxies --
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No esiteks, kuldse kujuga galaktikad --
08:06
those are the galaxies in the cluster.
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need on galaktikat mis on parves.
08:09
They're the ones that are embedded in that sea of dark matter
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Need on needsamad mis on selle tumeaine mere sees
08:13
that are causing the bending of the light
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mis põhjustavad valguse paindumise
08:15
to cause these optical illusions, or mirages, practically,
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tekitades sellised optilised illusioonid, või miraažid, praktiliselt,
08:18
of the background galaxies.
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taustgalaktikatest.
08:20
So the streaks that you see, all these streaks,
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Niiet need triibud mida te näete, kõik need triibud,
08:23
are actually distorted images of galaxies that are much further away.
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on tegelikult moonutatud pildid galaktikatest mis on palju kaugemal.
08:27
So what we can do, then, is based on how much distortion
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Mis me saame nüüd teha sõltub kui palju moonutusi
08:30
we see in those images, we can calculate how much mass
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me näeme nendel piltidel, me saame arvutada kui palju massi
08:34
there must be in this cluster.
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selles parves olema peaks.
08:36
And it's an enormous amount of mass.
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See on üüratu mass.
08:38
And also, you can tell by eye, by looking at this,
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Ja samuti, nagu silmaga näha seda vaadates,
08:40
that these arcs are not centered on individual galaxies.
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need kaared pole tsentreeritud individuaalsetele galaktikatele;
08:44
They are centered on some more spread out structure,
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nad on tsentreeritud mõnele enam hajunud struktuurile.
08:48
and that is the dark matter
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Ja see on tumeaine
08:52
in which the cluster is embedded, OK.
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mille sees see parv on, OK.
08:55
So this is the closest you can get to kind of seeing
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Ja see on parim võimalus mingil määral näha
08:57
at least the effects of the dark matter with your naked eye.
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tumeaine mõju palja silmaga.
09:00
OK, so, a quick review then, to see that you're following.
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OK, nüüd kiire ülevaade, et näha et te ikka jälgite.
09:03
So the evidence that we have
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Niiet tõendid mis meil on
09:05
that a quarter of the universe is dark matter --
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et veerand universumist on tumeaine --
09:07
this gravitationally attracting stuff --
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see gravitatsiooniliselt ligi tõmbav aine --
09:09
is that galaxies, the speed with which stars orbiting galaxies
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on see et galaktikad, kiirus millega tähed galaktikates orbiidil liiguvad
09:13
is much too large; it must be embedded in dark matter.
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on liialt suur; see peab olema tumeaine sees.
09:16
The speed with which galaxies within clusters are orbiting is much too large;
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Kiirus millega galaktikad liiguvad parvedes on liialt suur;
09:20
it must be embedded in dark matter.
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see peab olema tumeaine sees.
09:22
And we see these gravitational lensing effects, these distortions
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Ja me näeme neid gravitatsioonilise fokusseerimise tagajärgi, neid moonutusi
09:26
that say that, again, clusters are embedded in dark matter.
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mis räägivad et, jällegi, parved on tumeaine sees.
09:29
OK. So now, let's turn to dark energy.
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OK. Nüüd pöördume tumeenergia juurde.
09:33
So to understand the evidence for dark energy, we need to discuss something
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Et mõista tõendeid tumeenergia kohta, peame arutama midagi
09:36
that Stephen Hawking referred to in the previous session.
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millele Stephen Hawking viitas eelmisel perioodil.
09:40
And that is the fact that space itself is expanding.
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Ja see on fakt et ruum ise laieneb.
09:44
So if we imagine a section of our infinite universe --
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Nüüd kui me kujutame ette osa meie lõputust universumist, OK,
09:49
and so I've put down four spiral galaxies, OK --
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olen pannud siia neli spiraalset galaktikat, OK.
09:52
and imagine that you put down a set of tape measures,
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Ja kujutage ette et te panete siia grupi mõõdulinte,
09:56
so every line on here corresponds to a tape measure,
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nii et iga joon siin vastab mõõdulindile --
09:58
horizontal or vertical, for measuring where things are.
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horisontaalselt või vertikaalselt -- et mõõta kus asjad on.
10:02
If you could do this, what you would find
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Kui seda saaks teha, te leiaksite
10:04
that with each passing day, each passing year,
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et iga mööduva päevaga, iga mööduva aastaga,
10:07
each passing billions of years, OK,
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iga mööduva miljardi aastaga, OK,
10:10
the distance between galaxies is getting greater.
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vahemaa galaktikate vahel suureneb.
10:13
And it's not because galaxies are moving
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Ja see ei juhtu sellepärast et galaktikad liiguvad
10:14
away from each other through space.
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üksteisest eemale läbi ruumi;
10:17
They're not necessarily moving through space.
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nad ei liigu tingimata läbi ruumi.
10:19
They're moving away from each other
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Nad liiguvad üksteisest eemale
10:21
because space itself is getting bigger, OK.
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sest ruum ise suureneb, OK.
10:24
That's what the expansion of the universe or space means.
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See on see mida tähendab universumi või ruumi laienemine.
10:28
So they're moving further apart.
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Niiet nad liiguvad üksteisest eemale.
10:30
Now, what Stephen Hawking mentioned, as well,
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Nüüd, mida ka Stephen Hawking mainis,
10:34
is that after the Big Bang, space expanded at a very rapid rate.
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on et peale suurt pauku, ruum laienes väga kiiresti.
10:40
But because gravitationally attracting matter
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Kuna aga gravitatsiooniliselt tõmbav aine
10:44
is embedded in this space,
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on selle ruumi sees,
10:46
it tends to slow down the expansion of the space, OK.
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kipub ta ruumi suurenemist aeglustama, OK.
10:49
So the expansion slows down with time.
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Niiet laienemine aeglustub ajaga.
10:52
So, in the last century, OK, people debated
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Eelmisel sajandil, OK, inimesed arutlesid
10:56
about whether this expansion of space would continue forever;
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selle üle kas see ruumi laienemine jätkub igavesti,
11:01
whether it would slow down, you know,
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kas see aeglustub, mõistate,
11:03
will be slowing down, but continue forever;
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aeglustub, aga jätkub lõpmatult.
11:05
slow down and stop, asymptotically stop;
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Aeglustub ja peatub, asümptootiliselt,
11:10
or slow down, stop, and then reverse, so it starts to contract again.
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või aeglustub, peatub, ja siis pöördub ümber, ja hakkab jälle kokku tõmbuma.
11:15
So a little over a decade ago,
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No natuke üle aastakümne tagasi,
11:17
two groups of physicists and astronomers
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kaks füüsikute ja astronoomide gruppi
11:22
set out to measure the rate at which
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asusid mõõtma ruumi laienemise
11:24
the expansion of space was slowing down, OK.
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aeglustumist, OK.
11:28
By how much less is it expanding today,
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Aga kui palju aeglasemalt laienemine toimub täna,
11:30
compared to, say, a couple of billion years ago?
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võrreldes näiteks mõne miljardi aasta taguse ajaga.
11:33
The startling answer to this question, OK, from these experiments,
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Üllatav vastus sellele küsimusele, OK, nendest eksperimentidest,
11:38
was that space is expanding at a faster rate today
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oli et ruum laieneb kiiremini täna,
11:42
than it was a few billion years ago, OK.
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võrreldes mõne miljardi aasta taguse ajaga, OK.
11:45
So the expansion of space is actually speeding up.
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Niiet ruumi laienemine hoopis kiireneb.
11:48
This was a completely surprising result.
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See oli täiesti üllatav tulemus.
11:51
There is no persuasive theoretical argument for why this should happen, OK.
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Pole ühtegi veenvat teoreetilist argumenti miks see peaks juhtuma, OK.
11:57
No one was predicting ahead of time this is what's going to be found.
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Keegi ei ennustanud et see on see mida leitakse.
12:00
It was the opposite of what was expected.
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See oli vastupidine oodatule.
12:02
So we need something to be able to explain that.
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Niiet meil on vaja midagi millega saaks seda seletada.
12:05
Now it turns out, in the mathematics,
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Tuleb välja et, matemaatikas
12:07
you can put it in as a term that's an energy,
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saab seda seletada kui terminit mis on energia.
12:11
but it's a completely different type of energy
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Aga see on täiesti erinevat tüüpi energia
12:12
from anything we've ever seen before.
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võrreldes kõigega mida on varem nähtud.
12:14
We call it dark energy,
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Me kutsume seda tumeenergiaks
12:16
and it has this effect of causing space to expand.
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ja sellel on omadus põhjustada ruumi laienemist.
12:19
But we don't have a good motivation
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Aga meil pole head põhjust
12:21
for putting it in there at this point, OK.
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seda sinna sisse panna hetkel, OK.
12:23
So it's really unexplained as to why we need to put it in.
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Niiet on täiesti põhjendamata miks me selle sisse panema peame.
12:26
Now, so at this point, then, what I want to really emphasize to you,
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Nüüd, sellel hetkel, mida ma teile eriti rõhutada tahan
12:30
is that, first of all, dark matter and dark energy
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on esiteks, tumeaine ja tumeenergia
12:32
are completely different things, OK.
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on täiesti erinevad asjad, OK.
12:34
There are really two mysteries out there as to what makes up most of the universe,
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Tegelikult on kaks müsteeriumit selle kohta mis moodustab enamuse universumist,
12:38
and they have very different effects.
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ja neil on väga erinevad mõjud.
12:41
Dark matter, because it gravitationally attracts,
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Tumeaine, kuna ta gravitatsiooniliselt tõmbab,
12:44
it tends to encourage the growth of structure, OK.
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kaldub see soodustama struktuuride moodustumist, OK.
12:48
So clusters of galaxies will tend to form,
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Niiet galaktikate parved moodustuvad
12:51
because of all this gravitational attraction.
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selle gravitatsioonilise tõmbumise tõttu.
12:53
Dark energy, on the other hand,
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Tumeenergia, teisalt,
12:55
is putting more and more space between the galaxies,
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tekitab üha enam ruumi galaktikate vahele.
12:59
makes it, the gravitational attraction between them decrease,
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Mistõttu -- nendevaheline gravitatsiooniline tõmbumine -- väheneb,
13:02
and so it impedes the growth of structure.
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niiet see takistab struktuuride kasvu.
13:05
So by looking at things like clusters of galaxies,
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Niiet vaadates selliseid asju nagu galaktikate parv,
13:08
and how they -- their number density,
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ja kuidas nad -- nende numbriline tihedus,
13:12
how many there are as a function of time --
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kui palju neid on ajas --
13:14
we can learn about how dark matter and dark energy
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saame õppida kuidas tumeaine ja tumeenergia
13:18
compete against each other in structure forming.
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võistlevad üksteise vastu struktuuri moodustumisel.
13:21
In terms of dark matter, I said that we don't have any,
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Tumeainest, ütlesin et pole ühtegi,
13:24
you know, really persuasive argument for dark energy.
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mõistate, tõeliselt veenvat argumenti tumeenergiale.
13:28
Do we have anything for dark matter? And the answer is yes.
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Kas meil on midagi tumeaine kohta? Ja vastus on et: jah.
13:31
We have well-motivated candidates for the dark matter.
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Meil on head kandidaadid tumeainele.
13:34
Now, what do I mean by well motivated?
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Nüüd mida ma silmas pean öeldes head?
13:37
I mean that we have mathematically consistent theories
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Ma pean silmas et meil on matemaatiliselt terviklikud teooriad
13:42
that were actually introduced
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mille me võtsime kasutusele
13:44
to explain a completely different phenomenon, OK,
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et seletad hoopis teist nähtust, OK,
13:47
things that I haven't even talked about,
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asju millest ma pole isegi rääkinud,
13:49
that each predict the existence
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mis kõik ennustavad
13:52
of a very weakly interacting, new particle.
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väha nõrgalt koosmõjuva uue osakese olemasolu.
13:55
So, this is exactly what you want in physics:
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Ja see on täpselt see mida füüsikas tahetakse:
13:57
where a prediction comes out of a mathematically consistent theory
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kus ennustus tuleb matemaatiliselt terviklikust teooriast
14:01
that was actually developed for something else.
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mis tegelikult arendati millegi muu tarvis.
14:03
But we don't know if either of those
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Aga me ei tea kas kumbki neist
14:06
are actually the dark matter candidate, OK.
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on tegelikult tumeaine kandidaat, OK.
14:09
One or both, who knows? Or it could be something completely different.
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Üks või mõlemad, kes teab? Või see võib olla miski hoopis erinev.
14:12
Now, we look for these dark matter particles
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Me otsime neid tumeaine osakesi,
14:14
because, after all, they are here in the room, OK,
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sest lõppude lõpuks, nad on ju siin ruumis, OK,
14:17
and they didn't come in the door.
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ja nad ei tulnud uksest.
14:18
They just pass through anything.
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Nad lihtsalt läbivad kõike.
14:20
They can come through the building, through the Earth --
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Nad võivad tulla läbi maja, läbi maakera;
14:22
they're so non-interacting.
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nad on nii mitte-interaktiivsed.
14:24
So one way to look for them is to build detectors
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Üks võimalus nende leidmiseks on ehitada detektorid
14:27
that are extremely sensitive to a dark matter particle coming through and bumping it.
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mis on erakordselt tundlikud tumeaine osakeste suhtes mis liiguvad ja seda müksavad.
14:31
So a crystal that will ring if that happens.
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Näiteks kristall mis heliseb kui see juhtub.
14:34
So one of my colleagues up the road and his collaborators
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Üks mu kolleegidest siinsamas kõrval koos oma kaastöötajatega
14:36
have built such a detector.
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on ehitanud sellise detektori.
14:38
And they've put it deep down in an iron mine in Minnesota,
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Ja nad on selle pannud sügavale rauakaevandusse Minnesotas,
14:41
OK, deep under the ground, and in fact, in the last couple of days
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OK? -- sügavale maa alla -- ja tegelikult, paari viimase päeva jooksul
14:44
announced the most sensitive results so far.
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teatasid nad seni kõige tundlikematest tulemustest.
14:47
They haven't seen anything, OK, but it puts limits on what the mass
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Nad pole midagi näinud, OK, aga see annab piirid massi
14:50
and the interaction strength of these dark matter particles are.
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ja koosmõju tugevusele mida need tumeaine osakesed omavad.
14:53
There's going to be a satellite telescope launched later this year
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Hiljem sellel aastal lennutatakse välja satelliit-teleskoop.
14:57
and it will look towards the middle of the galaxy,
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Ja see vaatab galaktika keskme suunas,
15:00
to see if we can see dark matter particles annihilating
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et näha kas me saame näha tumeaine osakesi annihileerumas
15:02
and producing gamma rays that could be detected with this.
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ja gammakiirgust tekitamas, mida võiks selle abil avastada.
15:06
The Large Hadron Collider, a particle physics accelerator,
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Suur hadronite põrkur, osakeste füüsika kiirendi,
15:09
that we'll be turning on later this year.
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mille me lülitame sisse hiljem sellel aastal.
15:12
It is possible that dark matter particles might be produced
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On võimalik et tumeaine osakesed võivad tekkida
15:15
at the Large Hadron Collider.
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suures hadronite põrkuris.
15:17
Now, because they are so non-interactive,
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Kuna nad on aga nii mitte-interaktiivsed,
15:18
they will actually escape the detector,
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nad tegelikult mööduvad detektorist,
15:21
so their signature will be missing energy, OK.
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niiet nende märge on kadunud energia, OK.
15:24
Now, unfortunately, there is a lot of new physics
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Kahjuks aga, on palju uut füüsikat
15:27
whose signature could be missing energy,
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mille märge võib olla kadunud energia,
15:29
so it will be hard to tell the difference.
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niiet saab olema raske erinevust näha.
15:31
And finally, for future endeavors, there are telescopes being designed
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Ja lõpuks, tuleviku pürgimused, disainitakse teleskoope
15:36
specifically to address the questions of dark matter and dark energy --
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mille eesmärk on konkreetselt tumeaine ja tumeenergia küsimuste uurimine:
15:40
ground-based telescopes, and there are three space-based telescopes
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maa põhiseid teleskoope. Ja on kolm kosmoseteleskoopi
15:43
that are in competition right now
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mis on hetkel konkurentsis
15:45
to be launched to investigate dark matter and dark energy.
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et startida uurimaks tumeainet ja tumeenergiat.
15:48
So in terms of the big questions:
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Niiet mis puudutad suuri küsimusi:
15:50
what is dark matter? What is dark energy?
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Mis on tumeaine? Mis on tumeenergia?
15:52
The big questions facing physics.
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Suured küsimused füüsikas.
15:54
And I'm sure you have lots of questions,
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Usun et teil on palju küsimusi.
15:57
which I very much look forward to addressing
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Millele vastamist ootan ma suure huviga
15:59
over the next 72 hours, while I'm here. Thank you.
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järgneva 72 tunni jooksul mil ma siin olen, OK. Tänan teid.
16:01
(Applause)
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(Aplaus)
ABOUT THE SPEAKER
Patricia Burchat - Particle physicistPatricia Burchat studies the structure and distribution of dark matter and dark energy. These mysterious ingredients can't be measured in conventional ways, yet form a quarter of the mass of our universe.
Why you should listen
Patricia Burchat studies the universe's most basic ingredients -- the mysterious dark energy and dark matter that are massively more abundant than the visible stars and galaxies. She is one of the founders of the BaBar Collaboration at the Stanford Linear Accelerator Center, a project that's hoping to answer the question, "If there are as many anti-particles as there are particles, why can't we see all these anti-particles?"
She's a member of the Large Synoptic Survey Telescope project, which will allow scientists to monitor exploding supernovae and determine how fast the universe is expanding -- and map how mass is distributed throughout the universe. She's also part of Fermilab Experiment E791, studying the production and decay of charmed particles. Burchat received a Guggenheim Fellowship in 2005.
Patricia Burchat | Speaker | TED.com