Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:03:47,560 --> 00:03:48,640
Ok, welcome to CERN.
2
00:03:48,720 --> 00:03:52,520
This is in fact the control room
for the ATLAS experiment.
3
00:03:52,880 --> 00:03:57,040
ATLAS is one of the four
large experiments now going on
4
00:03:57,120 --> 00:04:00,640
at the LHC, the Large Hadron Collider.
5
00:04:01,200 --> 00:04:05,360
The Large Hadron Collider
is a huge ring of 27km,
6
00:04:05,520 --> 00:04:06,680
and that’s an accelerator
7
00:04:06,760 --> 00:04:09,960
where we accelerate protons
in two different directions,
8
00:04:10,040 --> 00:04:12,560
and then they collide in four points.
9
00:04:12,760 --> 00:04:15,160
We are just above
one of those colliding points
10
00:04:15,240 --> 00:04:17,400
at the ATLAS experiment.
11
00:04:17,760 --> 00:04:20,120
So ATLAS is both
12
00:04:20,200 --> 00:04:24,200
a large collaboration
of about 3,000 people,
13
00:04:24,680 --> 00:04:27,040
I'm one of them,
my name is Pauline Gagnon,
14
00:04:27,200 --> 00:04:28,080
I'm Canadian.
15
00:04:28,720 --> 00:04:32,240
I work for an American institute,
Indiana University,
16
00:04:32,720 --> 00:04:35,760
and I live here in France
and I work in Switzerland,
17
00:04:35,840 --> 00:04:38,520
but that's just about
the kind of sociology
18
00:04:38,960 --> 00:04:40,800
that you have with the people here
at CERN.
19
00:04:41,040 --> 00:04:43,600
So it's a very mixed background,
20
00:04:43,680 --> 00:04:48,680
in ATLAS alone we have people
from more than 70 different countries.
21
00:04:49,080 --> 00:04:53,240
There are only 38 countries participating
in the experiment,
22
00:04:53,360 --> 00:04:55,760
but since people like me with...
23
00:04:56,200 --> 00:04:58,200
I'm Canadian and I grew up
in an American institute,
24
00:04:58,280 --> 00:05:02,560
so, then there are people
from different countries working together.
25
00:05:03,520 --> 00:05:06,360
The common language to work
is broken English,
26
00:05:06,720 --> 00:05:08,560
so everybody speaks it
27
00:05:08,640 --> 00:05:12,920
with their own mistakes and all that,
their own accent.
28
00:05:13,000 --> 00:05:16,520
So... But people get along
and we usually get the work done.
29
00:05:23,200 --> 00:05:25,360
All this, you may wonder,
30
00:05:25,760 --> 00:05:27,120
what's the purpose of all this?
31
00:05:27,200 --> 00:05:30,600
Why do we go to such an extent?
32
00:05:30,880 --> 00:05:32,880
So much work, 3,000 people
33
00:05:32,960 --> 00:05:35,520
just to build the detector and work on it
34
00:05:35,600 --> 00:05:37,680
and analyse the data that comes out of it.
35
00:05:38,960 --> 00:05:41,360
Essentially, its just to increase
36
00:05:41,440 --> 00:05:44,240
the knowledge
about what matter is made of.
37
00:05:44,680 --> 00:05:47,800
What is the universe where we live,
38
00:05:48,200 --> 00:05:50,240
what is this place we are in
39
00:05:50,320 --> 00:05:52,920
and where did it come from.
where is it going.
40
00:05:53,000 --> 00:05:54,840
So, it's very fundamental questions,
41
00:05:54,920 --> 00:05:58,360
it's nothing that puts food on your plate
right away.
42
00:05:58,760 --> 00:06:02,240
The food might come later on,
because with research,
43
00:06:02,320 --> 00:06:04,960
you never know what will come out of it.
44
00:06:05,040 --> 00:06:06,560
We're going out and...
45
00:06:08,280 --> 00:06:10,080
let's see what we find!
46
00:06:10,160 --> 00:06:12,200
It's a bit like a mushroom hunt,
you know,
47
00:06:12,360 --> 00:06:14,120
you can bring back something
that is really good
48
00:06:14,200 --> 00:06:15,960
and you make a good dish
and you might not
49
00:06:16,120 --> 00:06:17,480
come back with anything suitable.
50
00:06:18,560 --> 00:06:21,480
So, I was saying earlier that we have the
accelerator
51
00:06:21,560 --> 00:06:23,240
which accelerates the particles
52
00:06:23,640 --> 00:06:25,440
and then we have the detectors
53
00:06:25,520 --> 00:06:27,440
that are there just to detect
what comes up.
54
00:06:28,120 --> 00:06:31,160
A detector is just a very fancy camera,
55
00:06:31,600 --> 00:06:34,360
so we take a snapshot of what happens
56
00:06:34,440 --> 00:06:37,240
when two protons come into collision.
57
00:06:38,520 --> 00:06:41,160
All the energy released in the collision
58
00:06:41,480 --> 00:06:44,440
then is in one small tiny point
59
00:06:44,840 --> 00:06:47,280
and it allows you to create a particle
60
00:06:47,360 --> 00:06:51,640
because E = MC2,
so the energy that you have put there,
61
00:06:51,720 --> 00:06:53,480
you can transform it into mass.
62
00:06:54,080 --> 00:06:57,920
the C squared is just the exchange rate
between energy and mass.
63
00:06:58,200 --> 00:07:02,640
So we can create new particles
and study how they behave.
64
00:09:11,880 --> 00:09:14,040
I saw in 1995 there was an opening at CERN
65
00:09:14,120 --> 00:09:16,400
and LHC was due to start very soon.
66
00:09:17,160 --> 00:09:20,480
And so this is why I decided
it could be a good opportunity
67
00:09:20,560 --> 00:09:21,720
and so that's why I jumped.
68
00:09:22,040 --> 00:09:23,120
So, I think...
69
00:09:24,240 --> 00:09:26,360
It's actually beautiful to be part of a...
70
00:09:27,360 --> 00:09:28,880
modern cathedral's building.
71
00:09:28,960 --> 00:09:33,000
That's the way I see it.
It's like being a community
72
00:09:33,280 --> 00:09:35,080
with a single aim and a single scope
73
00:09:35,640 --> 00:09:36,960
and we're producing machines
74
00:09:37,040 --> 00:09:40,480
that nobody has built before.
Like a cathedral.
75
00:09:48,720 --> 00:09:50,400
I'm in charge of the magnets at CERN
76
00:09:50,480 --> 00:09:52,920
everything that has to do
with magnets for the machines
77
00:09:53,640 --> 00:09:55,560
and I arrived at CERN in 1995
78
00:09:55,640 --> 00:09:58,200
after a few years of working
in thermonuclear fusion.
79
00:09:58,920 --> 00:10:01,600
I think I was lured here
by the adventure of the LHC,
80
00:10:01,680 --> 00:10:03,320
so it was at the beginning of the LHC.
81
00:10:04,000 --> 00:10:08,000
In fact where we are today is the hall
where we do all the maintenance,
82
00:10:08,080 --> 00:10:11,560
the work, the construction
and the reconstruction of the LHC magnets.
83
00:10:12,120 --> 00:10:15,400
We do mostly dipoles here,
and we work with quadrupoles as well
84
00:10:15,480 --> 00:10:16,760
these are the main elements
85
00:10:17,080 --> 00:10:20,600
that make up the superconducting cryostat
of the LHC.
86
00:10:23,120 --> 00:10:26,760
Well magnets are the main mass
in an accelerator.
87
00:10:27,200 --> 00:10:31,280
As you've seen in accelerators at CERN,
magnets guide particles,
88
00:10:31,360 --> 00:10:34,000
they drive them around on a circular path
89
00:10:34,360 --> 00:10:36,720
so that they can go back to
the real accelerating component
90
00:10:36,800 --> 00:10:40,560
which is a cavity.
But they need to do that thousands
91
00:10:40,640 --> 00:10:43,760
and tens of thousands of times a second,
like in the LHC.
92
00:10:44,000 --> 00:10:46,880
So the main function of the magnet is
to guide the particles back
93
00:10:47,080 --> 00:10:50,080
this is what we call dipoles,
and they have to focus them
94
00:10:50,160 --> 00:10:54,320
onto the closed orbit of the machine,
and these are the quadrapoles.
95
00:10:54,640 --> 00:10:55,520
In addition to that,
96
00:10:55,600 --> 00:10:58,480
the quadrapoles also squeeze the beam
down to a small size,
97
00:10:58,560 --> 00:11:01,480
smaller than a hair,
in the experimental region.
98
00:11:01,880 --> 00:11:03,680
This is the main function of the magnets.
99
00:11:06,640 --> 00:11:09,800
To give you an idea
of power and strength...
100
00:11:11,520 --> 00:11:12,360
I think...
101
00:11:13,600 --> 00:11:15,760
Let's start with electrical power
that we use
102
00:11:16,240 --> 00:11:18,760
because we need electrical power
to run the machines.
103
00:11:19,400 --> 00:11:25,320
So CERN uses roughly 160 megawatts
of electrical power
104
00:11:25,400 --> 00:11:29,760
only to run the accelerators
and that's more or less the consumption
105
00:11:29,840 --> 00:11:31,200
of a small city like Geneva.
106
00:11:31,880 --> 00:11:34,160
So it requires indeed a lot of power
107
00:11:34,520 --> 00:11:37,000
in spite of the fact that
we use superconductors.
108
00:11:39,280 --> 00:11:43,880
So the LHC itself uses about 60 megawatts
and the whole complex
109
00:11:43,960 --> 00:11:45,920
before the pre-injectors
110
00:11:46,000 --> 00:11:49,640
uses also about 60 megawatts
to inject the beam into the LHC.
111
00:11:51,200 --> 00:11:52,320
As to the magnetic field,
112
00:11:52,400 --> 00:11:55,560
to give you a feeling for how strong
the magnetic field is,
113
00:11:56,360 --> 00:11:58,040
you should imagine a magnetic field
114
00:11:58,120 --> 00:12:02,280
in our magnets of 8 tesla produces forces.
115
00:12:03,400 --> 00:12:05,880
These magnets are 15 meters long,
116
00:12:06,800 --> 00:12:08,840
and the forces produced on the magnet
117
00:12:09,520 --> 00:12:13,120
are in the order of 350 tonnes
per half magnet.
118
00:12:13,760 --> 00:12:19,800
So 350 tonnes per meter
of magnet for every half of the magnet.
119
00:12:20,960 --> 00:12:23,400
So it's a lot of weight
that needs to be held
120
00:12:23,480 --> 00:12:26,080
by the very strong structures
that we put around them.
121
00:12:26,320 --> 00:12:28,800
This is why the magnets are all encircled
122
00:12:28,880 --> 00:12:33,520
in these very strong structural steel
that keeps them together.
123
00:12:34,600 --> 00:12:38,280
As to the magnetic field itself,
the nominal field is 8 tesla.
124
00:12:39,400 --> 00:12:41,880
You can compare that to the magnetic field
of the earth
125
00:12:42,000 --> 00:12:45,360
which you can barely see
with a magnetic needle.
126
00:12:45,840 --> 00:12:49,440
so here in Geneva the earth is producing
about half a Gauss
127
00:12:50,760 --> 00:12:54,200
and if I compare that
to the magnetic field of the LHC,
128
00:12:54,800 --> 00:12:59,560
which is 8 Tesla,
that's a factor of 100,000 more.
129
00:12:59,920 --> 00:13:03,400
So the LHC produces 100,000
more magnetic field
130
00:13:03,800 --> 00:13:06,880
than that of the earth.
131
00:15:47,680 --> 00:15:50,080
We are 90 meters underground,
132
00:15:50,680 --> 00:15:52,640
between the Jura and the Lake of Geneva,
133
00:15:52,720 --> 00:15:56,240
and this is the cavern
of the ATLAS experiment.
134
00:15:57,240 --> 00:16:02,040
It's the biggest experiment
in high energy physics we ever built,
135
00:16:02,640 --> 00:16:07,960
so it's... the cavern is huge
it's 60m by 30m.
136
00:16:08,560 --> 00:16:11,560
Inside there is a detector,
it is 7,000 tons,
137
00:16:11,640 --> 00:16:14,720
it's the same weight
as the Tour d'Eiffel in Paris.
138
00:16:15,400 --> 00:16:19,440
And, the cavern is fully occupied,
in fact by our detector
139
00:16:19,720 --> 00:16:24,400
and this is one of the detectors
that has measured the Higgs-Boson,
140
00:16:24,840 --> 00:16:26,920
this year and last year.
141
00:16:27,480 --> 00:16:32,640
And now we are in maintenance mode so,
this is the period in which we stop,
142
00:16:32,720 --> 00:16:34,520
we open the detector and we work on it.
143
00:16:42,960 --> 00:16:46,960
So the aim of all this is quite varied,
144
00:16:47,040 --> 00:16:49,200
one of the main aims,
145
00:16:49,280 --> 00:16:52,160
one which you can also find in the press
146
00:16:52,240 --> 00:16:54,560
is the discovery of the Higgs-Boson.
147
00:16:55,640 --> 00:17:00,200
Apart from being a particle
it's a mechanism, it's a field,
148
00:17:00,880 --> 00:17:03,720
and it's the mechanism
which gives the mass
149
00:17:03,800 --> 00:17:05,400
to all the other particles.
150
00:17:06,040 --> 00:17:09,320
But this is only one of the aims
of this detector.
151
00:17:09,400 --> 00:17:11,200
This is a general purpose detector
152
00:17:11,800 --> 00:17:14,760
and can measure several aspects of nature.
153
00:17:15,280 --> 00:17:19,760
Several aspects of nature
in very tiny dimensions.
154
00:17:20,200 --> 00:17:26,240
And this backwards in time,
the accelerator itself is a time machine.
155
00:17:26,720 --> 00:17:30,840
Raising the energy allows us
to go back in time
156
00:17:30,920 --> 00:17:36,440
and to reach a point a tiny amount of time
after the big bang.
157
00:17:39,200 --> 00:17:44,960
The description of nature as we know today
is at the moment...
158
00:17:45,720 --> 00:17:47,000
I would say, quite complete,
159
00:17:47,080 --> 00:17:49,480
especially after the discovery
of the Higgs-Bosons.
160
00:17:50,080 --> 00:17:53,800
But there are many,
many things we don't understand, that...
161
00:17:53,880 --> 00:17:56,040
For which this detector has been built for
162
00:17:56,840 --> 00:17:59,960
and these for example are questions
about matter
163
00:18:00,920 --> 00:18:04,560
and well,
there is one very basic question
164
00:18:04,640 --> 00:18:08,160
that is the difference between
the amount of matter and anti-matter.
165
00:18:09,680 --> 00:18:14,720
Because all this... knowledge,
all this building of knowledge
166
00:18:14,800 --> 00:18:17,840
and building of theories tells you that...
167
00:18:18,320 --> 00:18:20,040
the big bang bang and
168
00:18:20,120 --> 00:18:23,760
at a certain moment in time
was beginning.
169
00:18:24,520 --> 00:18:30,040
And all the matter, all the matter
that exists in the universe now
170
00:18:30,640 --> 00:18:32,680
comes from a very small point
171
00:18:33,040 --> 00:18:38,120
from where everything expanded,
in a way,
172
00:18:38,600 --> 00:18:40,160
to give an image.
173
00:18:41,000 --> 00:18:46,880
But to have this final tiny point with
this enormous amount of energy
174
00:18:46,960 --> 00:18:50,320
and matter, density,
175
00:18:52,280 --> 00:18:55,000
you must have a way
to put all together...
176
00:18:55,680 --> 00:19:01,520
and, the only considerable way
you can see about this is symmetric...
177
00:19:01,960 --> 00:19:03,240
a symmetric way of thinking.
178
00:19:03,320 --> 00:19:06,360
That you must have the same amount of
matter and anti-matter.
179
00:19:07,200 --> 00:19:09,000
And then of course you can ask yourself:
180
00:19:09,760 --> 00:19:16,360
so why is it not myself
in anti-matter that is destroying me.
181
00:19:16,880 --> 00:19:20,360
So in a way there is a tiny difference
between the matter
182
00:19:20,440 --> 00:19:23,560
and anti-matter that makes all this exist.
183
00:19:25,120 --> 00:19:28,520
And this is certainly a mystery,
there are other mysteries
184
00:19:28,600 --> 00:19:34,840
like the amount of dark matter,
we see that if we look...
185
00:19:35,360 --> 00:19:39,720
we can look at this kind of phenomena
also in space
186
00:19:40,600 --> 00:19:42,520
and we can look at matter in space
187
00:19:42,680 --> 00:19:45,960
and we cannot really
compute totally the matter
188
00:19:46,040 --> 00:19:51,000
that is in space, we can compute it
but we see there is a deficit
189
00:19:51,080 --> 00:19:54,480
and that is what we call
the dark matter and the dark energy,
190
00:19:54,560 --> 00:20:00,840
that they are not exactly the same thing
to make this size of universe
191
00:20:00,920 --> 00:20:03,560
and this way the matter
is distributed possible.
192
00:20:04,560 --> 00:20:06,200
And this is certainly a mystery.
193
00:20:07,080 --> 00:20:09,640
Another mystery I would like to give you
is that...
194
00:20:10,720 --> 00:20:17,680
I explained to you that energy
and time are correlated
195
00:20:17,760 --> 00:20:22,400
and the product of energy
and time has to give you a constant.
196
00:20:23,680 --> 00:20:25,120
Now, if you think for a moment
197
00:20:25,200 --> 00:20:28,440
that the time you're aiming at is 'zero',
198
00:20:29,560 --> 00:20:33,840
then to keep this as a constant the energy
has to be infinite.
199
00:20:34,840 --> 00:20:38,320
So there is in itself a paradox here
200
00:20:38,400 --> 00:20:42,160
and something that
maybe we can't approach,
201
00:20:42,240 --> 00:20:43,400
we can do our best,
202
00:20:43,760 --> 00:20:47,040
but the time 'zero' is something
which is difficult.
203
00:23:00,800 --> 00:23:01,640
So...
204
00:23:02,520 --> 00:23:08,400
What we do in research is...
205
00:23:08,880 --> 00:23:11,280
sounds a bit strange,
I mean, we...
206
00:23:12,760 --> 00:23:14,600
on the one hand we want to
207
00:23:14,960 --> 00:23:19,640
test and confirm
208
00:23:19,720 --> 00:23:23,040
our present theory
209
00:23:23,760 --> 00:23:28,200
and at the same time we are always looking
for things which
210
00:23:30,040 --> 00:23:35,040
destroy our present theories
211
00:23:35,560 --> 00:23:41,640
to find something new.
212
00:23:49,080 --> 00:23:49,920
You...
213
00:23:52,000 --> 00:23:58,680
want me to explain the Higgs particle?
214
00:24:00,560 --> 00:24:04,920
Yeah... this is... yes...
I mean, the Higgs...
215
00:24:05,840 --> 00:24:09,440
Higgs mechanism... I have...
This is one of my...
216
00:24:11,800 --> 00:24:14,760
My... I mean, the...
217
00:24:15,480 --> 00:24:18,600
I have been wondering how one can
218
00:24:19,200 --> 00:24:22,240
correctly and easily explain
219
00:24:22,720 --> 00:24:26,160
the role of the Higgs field,
220
00:24:26,240 --> 00:24:28,680
Higgs mechanism and the Higgs particle.
221
00:24:29,360 --> 00:24:33,680
This is something
which is difficult for me to do.
222
00:24:36,640 --> 00:24:37,960
How can I explain?
223
00:24:38,280 --> 00:24:39,120
Is...
224
00:24:49,280 --> 00:24:54,680
Higgs-Boson has such a unique
and important role,
225
00:24:56,080 --> 00:25:00,520
even one that allows us to exist,
226
00:25:01,760 --> 00:25:03,720
this important particle
227
00:25:04,320 --> 00:25:08,000
hadn't been discovered
till just one year ago.
228
00:25:09,760 --> 00:25:14,320
So, in a way,
this is a very frustrating situation.
229
00:25:14,680 --> 00:25:17,000
We know the theory works very well,
230
00:25:17,280 --> 00:25:22,800
however one of the key elements
of the theory
231
00:25:23,840 --> 00:25:26,920
hasn't been confirmed by experiment,
232
00:25:27,000 --> 00:25:29,480
nobody has seen
whether this exists or not.
233
00:25:32,240 --> 00:25:35,600
Now it's very likely
234
00:25:37,640 --> 00:25:41,040
this will be discovered.
235
00:25:41,800 --> 00:25:43,600
So, in a sense,
236
00:25:43,680 --> 00:25:50,400
the last piece of our theory
has been found
237
00:25:50,480 --> 00:25:52,720
and put into the jigsaw puzzle,
238
00:25:54,400 --> 00:26:01,120
but in a jigsaw puzzle
this would be the completion,
239
00:26:01,200 --> 00:26:05,640
then you glue it and put it on the wall
240
00:26:05,720 --> 00:26:08,240
or take it apart.
241
00:26:08,320 --> 00:26:12,280
But in physics it doesn't work like this.
242
00:26:12,800 --> 00:26:17,880
Up to this point the analogy
of the jigsaw puzzle works fine,
243
00:26:18,040 --> 00:26:24,120
but after that it doesn't hold anymore.
244
00:26:24,520 --> 00:26:28,080
What we want to do is...
245
00:26:30,880 --> 00:26:35,040
first of all, we have to confirm
246
00:26:35,400 --> 00:26:38,920
if this particle is really the last piece
of the jigsaw puzzle,
247
00:26:39,320 --> 00:26:45,640
not something similar
but it maybe something totally different.
248
00:28:13,680 --> 00:28:19,240
We have a picture,
a cosmological history of our universe,
249
00:28:19,320 --> 00:28:23,640
nobody tells us that is the truth
but within our present knowledge
250
00:28:23,800 --> 00:28:29,360
this is the best we can do and indeed
it does explain very nicely
251
00:28:29,480 --> 00:28:31,480
everything we are able to observe.
252
00:28:31,800 --> 00:28:34,240
Maybe we come up with new observation.
253
00:28:34,560 --> 00:28:35,400
Remember,
254
00:28:36,160 --> 00:28:41,560
what we are studying at the LHC
255
00:28:41,840 --> 00:28:43,360
is matter,
256
00:28:43,720 --> 00:28:50,560
so matter, well visible matter,
constitutes only 4% of the universe.
257
00:28:51,160 --> 00:28:56,840
All the rest is unknown, dark matter,
that we know it exists
258
00:28:57,040 --> 00:28:59,080
but we don't know what it is.
259
00:28:59,360 --> 00:29:03,200
And something even more mysterious
is dark energy.
260
00:29:03,640 --> 00:29:08,840
Again we suspect it exists
261
00:29:08,920 --> 00:29:11,080
cause we need it to explain
262
00:29:11,400 --> 00:29:14,440
given properties
of the evolution of the universe
263
00:29:14,760 --> 00:29:17,840
but again
we don't have any idea what it is.
264
00:29:18,120 --> 00:29:20,760
So today we are in a situation
265
00:29:21,080 --> 00:29:27,520
where we understand 4% of the universe
266
00:29:27,600 --> 00:29:32,280
and we ignore what the rest of it is.
267
00:29:39,360 --> 00:29:42,760
So the specific place where we are now,
268
00:29:42,840 --> 00:29:44,280
this is ALICE experiment,
269
00:29:44,840 --> 00:29:49,680
we are looking to recreate
primordial matter.
270
00:29:49,760 --> 00:29:54,480
Matter as it existed shortly after
the big bang.
271
00:29:54,800 --> 00:29:59,320
Here we are talking fractions
of a micro-second
272
00:29:59,400 --> 00:30:02,360
after the beginning of the universe.
273
00:30:02,800 --> 00:30:05,960
At that time temperatures
were extremely high,
274
00:30:06,280 --> 00:30:08,480
energy density was very high
275
00:30:08,840 --> 00:30:12,840
and matter was in a completely
different shape than today.
276
00:30:13,080 --> 00:30:16,600
So we recreate this primordial matter,
277
00:30:17,200 --> 00:30:22,680
try to understand nature
and properties of this matter
278
00:30:22,920 --> 00:30:24,800
and then how it evolved
279
00:30:24,880 --> 00:30:29,720
from its state in the early universe
to the state as we know it today.
280
00:30:31,720 --> 00:30:35,360
Imagine in a single collision
281
00:30:35,680 --> 00:30:38,440
we are producing, about 10,000 particles,
282
00:30:38,680 --> 00:30:41,280
running through the equipment
283
00:30:41,360 --> 00:30:46,280
that must be identified.
284
00:30:46,360 --> 00:30:53,080
So we don't see the particle itself,
we take a picture of the track
285
00:30:53,160 --> 00:30:56,880
a particle leaves
as it passes through the detector.
286
00:30:57,200 --> 00:31:03,840
Like if you look at a ski slope,
287
00:31:04,360 --> 00:31:08,120
you don't see the skier
288
00:31:08,400 --> 00:31:13,400
but you can identify weight,
size and direction
289
00:31:14,000 --> 00:31:19,320
by the traces he leaves behind.
290
00:31:19,680 --> 00:31:24,520
And for a full trace of the skier
291
00:31:24,840 --> 00:31:28,720
you need a big field!
292
00:31:30,920 --> 00:31:34,360
We use brute force, we aren't very smart.
293
00:31:34,760 --> 00:31:40,040
We use the energy from a collision
294
00:31:40,120 --> 00:31:44,840
to create these new particles.
295
00:31:45,120 --> 00:31:49,200
We need to bring a small particle
296
00:31:49,280 --> 00:31:52,600
up to a very high speed,
297
00:31:52,680 --> 00:31:57,600
close to the speed of light,
298
00:31:57,920 --> 00:32:00,240
so for this we just need big machines!
299
00:32:00,600 --> 00:32:07,440
Using magnets to make the particle turn
and electricity to accelerate it
300
00:32:07,720 --> 00:32:12,520
and a million other things
to make the whole thing work!
301
00:32:14,480 --> 00:32:19,320
And I think CERN is a really good example
302
00:32:19,680 --> 00:32:25,600
for humanity following a common objective.
303
00:32:26,240 --> 00:32:29,800
Even if we don't discover anything
in science,
304
00:32:29,960 --> 00:32:33,440
I think having achieved that
is a major achievement.
305
00:32:37,040 --> 00:32:39,560
So she recognised
that they pushed the crash button?
306
00:32:40,160 --> 00:32:42,120
Are we speaking about
this new crash button
307
00:32:42,200 --> 00:32:45,720
which we installed like a year ago
in Utrecht, or not?
308
00:32:46,920 --> 00:32:49,640
-I don't know.
-This, I think, we have to understand.
309
00:32:49,720 --> 00:32:51,680
I think we really have to understand this.
310
00:32:51,760 --> 00:32:54,560
The crash button was somehow
recognised as being pushed...
311
00:32:57,720 --> 00:33:00,520
I think Christoph Schäfer
also has to be involved.
312
00:33:00,600 --> 00:33:03,160
So, that's the suspicion right now?
313
00:33:03,240 --> 00:33:05,080
That someone hit the crash button?
314
00:33:05,400 --> 00:33:08,240
-No.
-So, that's the question.
315
00:33:08,400 --> 00:33:10,400
So why did it turn off in the first place?
316
00:33:10,480 --> 00:33:13,240
All the information is inclusive
of an emergency stop.
317
00:33:14,360 --> 00:33:16,240
So it's as if some hit the crash button?
318
00:33:16,320 --> 00:33:17,680
-So...
-I mean...
319
00:33:18,440 --> 00:33:21,560
I don't know the meaning of
emergency stop...
320
00:33:21,640 --> 00:33:24,560
That's OK, that's OK.
321
00:33:27,080 --> 00:33:29,320
So, the law is as if...
322
00:33:29,800 --> 00:33:32,880
it's as if someone hit the crash button?
323
00:33:32,960 --> 00:33:34,040
You don't think someone did,
324
00:33:34,120 --> 00:33:36,320
but it's as if someone hit
the crash button.
325
00:33:38,240 --> 00:33:39,240
OK.
326
00:33:39,320 --> 00:33:42,440
So the question is about first statement.
327
00:33:42,600 --> 00:33:45,680
You looked at reprocessed
versus prompt data
328
00:33:45,760 --> 00:33:47,680
and you decided to stay with the prompt,
329
00:33:47,760 --> 00:33:51,520
but in the reprocessed data,
there are not just changes for jets,
330
00:33:52,040 --> 00:33:55,640
so I find the statement a little bit...
331
00:33:56,560 --> 00:33:57,640
surprising.
332
00:34:01,200 --> 00:34:04,520
So, the question is,
is it a quantitative measure
333
00:34:04,600 --> 00:34:07,960
of these major differences,
which you can see you have some...
334
00:34:08,400 --> 00:34:10,240
plots also that show that.
335
00:34:10,320 --> 00:34:12,400
If it's in the back-up,
we can look at it later
336
00:34:12,480 --> 00:34:14,160
but I don't want to kill the stream.
337
00:34:14,240 --> 00:34:16,440
I'm not quite sure
if I put it in the back-up or not.
338
00:34:16,520 --> 00:34:17,600
Just more than a sentence
339
00:34:17,680 --> 00:34:19,920
I think that's
what I'll learn from the question.
340
00:34:20,560 --> 00:34:23,480
OK, we can take it offline
and we can go on from here.
341
00:34:32,440 --> 00:34:35,240
You look frozen,
are you still, you know, alive?
342
00:34:40,600 --> 00:34:42,880
I think the shock of this question
was too much.
343
00:34:45,560 --> 00:34:46,560
He's gone.
344
00:34:46,920 --> 00:34:48,160
OK, he turned invisible.
345
00:34:50,400 --> 00:34:52,440
So no more questions until the end please.
346
00:34:55,960 --> 00:34:58,080
Can anybody...
347
00:34:59,080 --> 00:35:00,840
outside CERN still hear us?
348
00:35:01,480 --> 00:35:03,360
-I can.
-Oh, good.
349
00:35:04,760 --> 00:35:06,440
So I can go and sit down and just wait.
350
00:35:09,960 --> 00:35:15,480
In the beginning I was heavily involved
in building a system
351
00:35:15,560 --> 00:35:17,080
that we call 'the trigger system'.
352
00:35:17,520 --> 00:35:21,680
This trigger system
actually selects online,
353
00:35:21,760 --> 00:35:22,720
in real time,
354
00:35:23,200 --> 00:35:28,680
the interesting collisions to be recorded
and analysed later.
355
00:35:29,240 --> 00:35:31,840
This involved the development
356
00:35:31,920 --> 00:35:36,240
of an electronic system
which operates very fast.
357
00:35:36,960 --> 00:35:42,080
It looks at a collision 40 million times
per second,
358
00:35:42,360 --> 00:35:45,520
like a digital camera,
359
00:35:46,040 --> 00:35:48,520
which takes 40 million pictures
per second.
360
00:35:49,480 --> 00:35:52,680
It not only takes the pictures
361
00:35:52,760 --> 00:35:56,800
but it looks for interesting patterns
for example.
362
00:35:57,320 --> 00:35:59,600
And if there are,
363
00:36:00,120 --> 00:36:05,360
which is only the case
a few hundred times per second,
364
00:36:05,760 --> 00:36:08,760
then the trigger system recognizes these
365
00:36:09,240 --> 00:36:14,920
and marks them for recording.
366
00:36:15,000 --> 00:36:21,600
Like if you take lots of snapshots
with a camera
367
00:36:21,680 --> 00:36:23,880
but you eliminate those
that you do not like.
368
00:36:24,200 --> 00:36:27,440
But we do that online extremely fast.
369
00:36:34,680 --> 00:36:37,600
Our first important discovery
370
00:36:37,920 --> 00:36:42,440
was a particle that looks very much like
the so-called Higgs particle,
371
00:36:42,720 --> 00:36:45,400
which is also called God particle,
372
00:36:45,480 --> 00:36:49,480
but this is a term which physicists
don't really like.
373
00:36:49,720 --> 00:36:52,240
We have discovered a very new particle
374
00:36:52,320 --> 00:36:54,560
and now we are going to measure
all its properties
375
00:36:54,640 --> 00:36:59,840
and make sure it is really
the long sought Higgs particle
376
00:36:59,920 --> 00:37:02,320
or if it is indeed something
completely new.
377
00:37:02,800 --> 00:37:07,400
But actually this experiment was built
for another main purpose
378
00:37:07,480 --> 00:37:13,800
which was to discover
if there are new forces in physics.
379
00:37:14,000 --> 00:37:16,520
We all know gravity, for example,
380
00:37:16,600 --> 00:37:18,000
but there are also other forces
381
00:37:18,720 --> 00:37:21,280
such as electro-magnetic forces
in the universe.
382
00:37:21,680 --> 00:37:25,680
But maybe there are other forces
we do not know about
383
00:37:25,760 --> 00:37:30,080
and this could be discovered here.
384
00:37:30,560 --> 00:37:35,920
We could also discover
completely new spatial dimensions
385
00:37:36,280 --> 00:37:37,400
which might be very small
386
00:37:37,480 --> 00:37:40,080
meaning till now
we haven't been able to see them,
387
00:37:40,640 --> 00:37:44,240
but with a tool like the Large Hadron
Collider and this experiment
388
00:37:45,400 --> 00:37:50,800
we can use them like a giant microscope
389
00:37:50,880 --> 00:37:53,280
and look deep into nature
390
00:37:53,360 --> 00:37:55,800
and we hope to find something very new.
391
00:37:57,760 --> 00:37:59,800
For example it is imaginable
392
00:37:59,880 --> 00:38:03,080
that gravity becomes
a very, very strong force.
393
00:38:03,160 --> 00:38:07,520
Much stronger than we are used to it
when we go to very small distances.
394
00:38:08,120 --> 00:38:10,320
For example: when you smash 2 protons
395
00:38:11,560 --> 00:38:14,000
against each other
as it is done in the LHC
396
00:38:14,520 --> 00:38:17,760
then you really come
to very, very small distances.
397
00:38:17,840 --> 00:38:20,320
And it is possible
that gravity becomes very strong.
398
00:38:20,640 --> 00:38:26,760
So if gravity becomes strong
then we can also create mini black holes.
399
00:38:26,840 --> 00:38:28,680
Microscopic black holes.
400
00:38:29,120 --> 00:38:30,840
So this would be a spectacular
401
00:38:31,840 --> 00:38:35,760
new signature
for up to now unknown physics.
402
00:38:38,000 --> 00:38:39,640
It's a constant struggle
403
00:38:39,720 --> 00:38:41,880
and of course
sometimes the kids complain,
404
00:38:41,960 --> 00:38:48,160
'Mummy there's nothing to eat!'
but I'm not alone
405
00:38:48,240 --> 00:38:52,040
and one has to get all the help one can.
406
00:38:53,160 --> 00:38:57,360
I think even if the family suffers,
in the end
407
00:38:57,440 --> 00:39:01,520
they see how enthusiastic we are
408
00:39:01,600 --> 00:39:04,400
and they see that we've achieved
409
00:39:04,480 --> 00:39:08,760
something really satisfying
that can show new ways
410
00:39:08,840 --> 00:39:12,000
and normally families understand.
411
00:39:13,680 --> 00:39:18,280
But I should also say there have been
lots of divorces at CERN,
412
00:39:19,120 --> 00:39:22,440
mainly because of just too much work.
413
00:39:23,160 --> 00:39:25,080
People are enthusiastic though,
414
00:39:25,160 --> 00:39:30,000
these are not people
that come at 9 and leave at 5
415
00:39:30,080 --> 00:39:34,160
and look at their watch,
they really like to spend the time here
416
00:39:34,240 --> 00:39:39,280
and put in
all the means possible to get results
417
00:39:39,360 --> 00:39:41,560
and also to get personal satisfaction.
418
00:39:46,000 --> 00:39:52,560
This centre is at CERN and has essentially
two main and very important connections.
419
00:39:52,840 --> 00:39:56,760
One connection
brings us to the experiment,
420
00:39:57,240 --> 00:40:01,480
so essentially the main flux of data is
from the experiments to here.
421
00:40:01,880 --> 00:40:05,360
So when beams collide,
422
00:40:06,040 --> 00:40:09,760
the results of the collision are recorded,
423
00:40:10,120 --> 00:40:12,920
filtered
through different levels of filtering
424
00:40:13,240 --> 00:40:17,800
and eventually they are shipped here
via a dedicated network.
425
00:40:18,160 --> 00:40:19,600
So this is the first connection.
426
00:40:20,280 --> 00:40:27,120
Data arrives here and is stored
and ready to be immediately analysed.
427
00:40:27,680 --> 00:40:29,640
This is just
the first part of the analysis,
428
00:40:29,720 --> 00:40:31,960
we call it 'general reconstruction'.
429
00:40:32,520 --> 00:40:34,040
The idea here is that
430
00:40:34,120 --> 00:40:37,200
from the raw data
431
00:40:37,840 --> 00:40:40,760
which we receive from the experiments
432
00:40:42,600 --> 00:40:46,640
we reconstruct, for example, trajectories,
from which you can
433
00:40:47,240 --> 00:40:53,600
identify particles
and assign them energies and directions.
434
00:41:00,040 --> 00:41:02,160
This data is also shipped outside.
435
00:41:03,360 --> 00:41:09,560
They are shipped directly
from CERN to important computer centres,
436
00:41:09,800 --> 00:41:11,480
more or less comparable to this one
437
00:41:12,120 --> 00:41:17,000
which in turn redistribute data
to other places
438
00:41:17,080 --> 00:41:20,960
like universities
or university type facilities
439
00:41:21,280 --> 00:41:25,400
where the final analysis will be done
440
00:41:25,480 --> 00:41:28,240
or other activities connected
with analysis of the data.
441
00:41:28,440 --> 00:41:32,880
I think one can visualize data
coming from the experiment,
442
00:41:33,360 --> 00:41:38,720
being stored, used for initial
reconstruction and also distributed.
443
00:41:39,320 --> 00:41:43,240
So this is the backbone of our activity.
444
00:41:46,920 --> 00:41:48,520
I was born in 1964,
445
00:41:48,800 --> 00:41:52,520
and, talking with people of my age,
446
00:41:53,080 --> 00:41:59,240
came to the conclusion
that the Apollo period
447
00:41:59,320 --> 00:42:03,800
end of the 60's beginning of the 70's
had a big influence on us.
448
00:42:03,880 --> 00:42:08,600
Initially it was a big fascination
with astronomy and astronauts
449
00:42:09,160 --> 00:42:16,040
which eventually, getting older,
became an interest in physics and so on.
450
00:42:16,280 --> 00:42:21,800
I think there's a specific correlation
between astronomy, physics
451
00:42:21,880 --> 00:42:28,280
and that period of space exploration.
452
00:42:30,000 --> 00:42:35,240
On one side there's astronomy
with gigantic distances,
453
00:42:35,520 --> 00:42:42,000
worlds you can not really visit directly,
and there's particle physics
454
00:42:42,360 --> 00:42:46,560
which is a kind of mirror image,
you go smaller and smaller.
455
00:42:46,640 --> 00:42:53,520
So you find worlds which are really
fascinating, strange sometimes, bizarre
456
00:42:54,160 --> 00:42:58,120
but it's clearly one of the things
457
00:42:58,200 --> 00:43:01,520
which moved me to go into physics.
458
00:43:02,000 --> 00:43:09,000
And now, even if I'm more in computing,
there's a pride in saying
459
00:43:09,720 --> 00:43:15,600
these experiments are something
really interesting, really cool,
460
00:43:16,200 --> 00:43:20,240
and we are making our small contribution.
461
00:43:20,320 --> 00:43:26,200
I think for somebody
with a physics background that CERN,
462
00:43:26,800 --> 00:43:29,480
even if they move on,
keeps this fascination.
463
00:43:29,560 --> 00:43:31,840
It's our home.
464
00:43:33,040 --> 00:43:34,880
It's our dream place.
465
00:43:36,560 --> 00:43:38,000
I think it is so.
466
00:45:55,960 --> 00:45:57,520
We have our own fire brigade.
467
00:45:58,080 --> 00:46:00,320
We have our own emergency services.
468
00:46:01,040 --> 00:46:06,280
Actually we are like a city,
and this is the challenge also in my job,
469
00:46:06,360 --> 00:46:09,760
because you asked me in the beginning
where we are here.
470
00:46:10,280 --> 00:46:13,240
I have to, we have to manage a small city,
471
00:46:14,000 --> 00:46:17,160
and to give you an idea
of what I mean by city
472
00:46:18,040 --> 00:46:21,920
we have roughly 10,800 guest scientists
473
00:46:22,000 --> 00:46:23,480
coming from all over the world,
474
00:46:24,080 --> 00:46:29,480
One hundred and twenty nationalities,
we have roughly 2,500 staff,
475
00:46:30,400 --> 00:46:35,200
we have 500 postdocs ,
500 students and apprentices.
476
00:46:35,560 --> 00:46:40,400
So it's a population
and needs accommodation and services
477
00:46:40,840 --> 00:46:45,640
as any customer would need
in a small city.
478
00:46:52,760 --> 00:46:59,000
In some sense we are both an organisation
like any other,
479
00:46:59,080 --> 00:47:03,200
but we also provide our own legislation,
if you like.
480
00:47:03,600 --> 00:47:05,800
Because the convention gives us the right
481
00:47:05,880 --> 00:47:10,000
and also the obligation to handle
certain things ourselves.
482
00:47:10,080 --> 00:47:14,280
For example, if we fix our salaries
we cannot simply do it,
483
00:47:14,680 --> 00:47:16,800
we have to do it according to
484
00:47:17,160 --> 00:47:20,480
the rules approved
by our 20 member states.
485
00:47:21,240 --> 00:47:26,600
In some sense we're a kind of
state in the states.
486
00:47:28,520 --> 00:47:30,120
What we need is a long breath.
487
00:47:31,040 --> 00:47:36,080
This is sometimes a problem
if you discuss things with politicians.
488
00:47:36,640 --> 00:47:41,200
They're used to working in horizons
of 3 - 5 years.
489
00:47:41,640 --> 00:47:46,560
They expect a return on investment
which is more or less immediate.
490
00:47:47,080 --> 00:47:48,280
Immediate means tomorrow.
491
00:47:49,080 --> 00:47:52,320
But we have seen by the example
of the world wide web
492
00:47:52,400 --> 00:47:53,880
which was invented here at CERN ,
493
00:47:54,800 --> 00:48:01,600
you need on average at least 10 - 15 years
494
00:48:02,160 --> 00:48:06,040
between the first basic ideas
495
00:48:06,880 --> 00:48:09,160
and the first industrial product.
496
00:49:07,800 --> 00:49:09,960
So, I'm a theoretical physicist.
497
00:49:10,440 --> 00:49:12,920
My job is to come up with some ideas,
498
00:49:13,120 --> 00:49:14,720
some possible explanations,
499
00:49:15,280 --> 00:49:19,160
then I try to understand
what are the consequences
500
00:49:19,240 --> 00:49:23,880
of these ideas and how you can test
these ideas using experimental result.
501
00:49:24,200 --> 00:49:28,400
In particular, experimental results
being obtained now in this LHC,
502
00:49:28,480 --> 00:49:32,280
this big machine that has been built here
at CERN
503
00:49:32,640 --> 00:49:34,880
which is working pretty well
at the moment.
504
00:49:43,040 --> 00:49:46,840
Good ideas can come at any moment
and you have to be ready.
505
00:49:53,480 --> 00:49:54,680
It can be dangerous too!
506
00:49:54,760 --> 00:49:57,160
If you have an idea
while you're driving your car
507
00:49:57,240 --> 00:50:00,200
you have to keep your ideas.
508
00:50:00,640 --> 00:50:05,200
When you getting back home
to take a little piece of paper
509
00:50:05,280 --> 00:50:09,080
to writing down your ideas
and try to finish your computation.
510
00:50:12,680 --> 00:50:16,320
Most of the time you make mistakes
511
00:50:16,400 --> 00:50:22,240
but from time to time you are right
and you understand something new.
512
00:50:22,760 --> 00:50:27,640
That's fantastic, it's a good feeling
when you come home in the evening
513
00:50:27,960 --> 00:50:32,440
you're feeling very good
514
00:50:32,520 --> 00:50:35,360
because you know more than in the morning.
515
00:50:36,560 --> 00:50:39,600
The feeling
of having thought of something
516
00:50:39,680 --> 00:50:43,600
nobody has done before
517
00:50:44,360 --> 00:50:47,160
is what's really exciting about research.
518
00:50:48,840 --> 00:50:54,040
For a few moments you are
the only person on earth
519
00:50:54,320 --> 00:50:58,960
who has a
clear understanding of a problem.
520
00:51:01,040 --> 00:51:04,520
Discovering the Higgs-Boson is not
like discovering yet another particle.
521
00:51:04,880 --> 00:51:11,040
What we are really after is trying
to understand some fundamental laws,
522
00:51:11,120 --> 00:51:13,920
some fundamental principles
that govern the universe.
523
00:51:14,400 --> 00:51:20,600
So for a very long time
one main theme of particle physics
524
00:51:20,680 --> 00:51:24,920
and theoretical physics
was the Gauge principle.
525
00:51:25,000 --> 00:51:27,720
So the Gauge principle
is really the process that explains
526
00:51:27,800 --> 00:51:31,320
how particles interact with each other
with the exchange of the Gauge-Boson.
527
00:51:31,960 --> 00:51:35,400
And maybe with the discovery of
the Higgs-Boson we are about to discover
528
00:51:35,480 --> 00:51:40,680
a new fundamental principle of nature
that could really govern
529
00:51:42,200 --> 00:51:43,800
how the universe is structured.
530
00:51:45,240 --> 00:51:48,520
But again, we are not so much interested
in new particles.
531
00:51:48,880 --> 00:51:50,840
What we really want to understand is
532
00:51:51,120 --> 00:51:53,480
'what is the principle
behind these new particles?'
533
00:51:54,240 --> 00:51:56,560
Is the discovery of the new particle
534
00:51:56,640 --> 00:51:59,600
telling me something
more fundamental about nature:
535
00:52:00,000 --> 00:52:04,520
is there a new space-time dimension,
536
00:52:04,600 --> 00:52:06,880
is there a new interaction...
537
00:52:07,200 --> 00:52:10,920
a fundamental interaction
between those particles.
538
00:52:11,000 --> 00:52:13,400
That's really what we are about.
539
00:52:14,080 --> 00:52:18,200
I mean, the fact that till now
we understand interaction
540
00:52:18,280 --> 00:52:20,200
as the exchange of Gauge-Bosom,
541
00:52:20,360 --> 00:52:25,120
that was a really big step forward
in the understanding of nature.
542
00:52:25,920 --> 00:52:30,800
But still there are a few things
that we don't quite understand.
543
00:52:30,880 --> 00:52:33,760
For instance the
fact that electro-magnetism is described
544
00:52:33,840 --> 00:52:37,640
by one particular symmetry of nature,
there is a weak interaction
545
00:52:37,720 --> 00:52:41,240
which is described by another symmetry,
there is a strong interaction,
546
00:52:41,320 --> 00:52:42,520
yet another symmetry.
547
00:52:43,360 --> 00:52:45,520
Why those particular symmetries?
548
00:52:45,600 --> 00:52:49,040
Is there something deeper
behind those symmetries,
549
00:52:49,240 --> 00:52:50,840
a bigger symmetry for instance?
550
00:52:50,920 --> 00:52:55,360
That will unify all those symmetries
associated to the different interactions.
551
00:52:56,520 --> 00:52:59,200
And, yeah, we are trying to understand
these kinds of things.
552
00:53:00,960 --> 00:53:04,800
We have good ideas but we still don't know
if our ideas are true or not.
553
00:54:57,440 --> 00:54:59,520
I mean, I'm not a physicist
554
00:54:59,760 --> 00:55:06,080
and I used to say I'm here to develop
the toys for physicists.
555
00:55:06,160 --> 00:55:10,080
So I'm involved with the machines.
556
00:55:10,480 --> 00:55:15,320
There are several people at CERN
557
00:55:16,120 --> 00:55:20,560
who decide what has to be done
on the physics' side
558
00:55:21,120 --> 00:55:24,920
and we are responsible
for developing the tools
559
00:55:25,360 --> 00:55:29,640
for these people to carry out
their research.
560
00:55:37,600 --> 00:55:40,160
There is not really hierarchies
here at CERN,
561
00:55:40,560 --> 00:55:42,120
at least that’s my feeling,
562
00:55:42,200 --> 00:55:45,880
there are people from the physics side
563
00:55:47,840 --> 00:55:50,280
deciding what has to be done
564
00:55:50,640 --> 00:55:52,720
and we're here to provide them
565
00:55:52,800 --> 00:55:58,200
with the required tools
to be able to investigate
566
00:55:58,280 --> 00:56:02,120
what they are looking for
so there is no real hierarchies,
567
00:56:02,200 --> 00:56:08,760
there are different specialties at CERN
568
00:56:09,240 --> 00:56:12,000
in the technical part.
569
00:56:12,880 --> 00:56:14,680
Our section is MDT,
570
00:56:14,760 --> 00:56:19,800
my section leader used to
translate that to Making Dreams True.
571
00:56:19,880 --> 00:56:25,080
People ask for dedicated tools
572
00:56:25,160 --> 00:56:28,040
and we are here to try to develop
these tools.
573
00:56:32,800 --> 00:56:35,920
We are presently working
on the new generation
574
00:56:36,000 --> 00:56:40,800
of superconducting magnets
using new technology,
575
00:56:40,880 --> 00:56:45,840
Niobium 3 Tin (Nb3Sn)
superconducting cables,
576
00:56:46,240 --> 00:56:49,680
in order to reach a higher field
that will be required
577
00:56:49,760 --> 00:56:52,920
for the upgrade of the luminosity
of the LHC.
578
00:56:53,640 --> 00:56:56,480
The magnets presently installed
in the LHC
579
00:56:57,320 --> 00:56:59,800
are based on Niobium Titanium technology
580
00:56:59,880 --> 00:57:05,360
and will reach the limit of
the magnetic field that can be reached
581
00:57:05,440 --> 00:57:08,560
with this kind of superconductor.
582
00:57:09,920 --> 00:57:14,000
For example we're working
on a new dipole
583
00:57:14,320 --> 00:57:18,480
with 100mm Bohr and 13 Tesla.
584
00:57:18,960 --> 00:57:24,600
and to give you a rough idea of
what this represents,
585
00:57:25,360 --> 00:57:30,240
the required niobium cable
to produce one coil
586
00:57:30,680 --> 00:57:35,520
is around 100,000 Swiss francs per coil
587
00:57:35,800 --> 00:57:37,920
and we need 4 coils inside.
588
00:57:38,600 --> 00:57:43,480
You only need a few seconds
to destroy the cable so,
589
00:57:44,280 --> 00:57:46,840
this is quite difficult to deal with.
590
01:01:44,720 --> 01:01:46,640
We're working with superconductivity
591
01:01:46,720 --> 01:01:51,360
so the magnets
we have to test have to cool down
592
01:01:51,440 --> 01:01:56,200
to a very low temperature,
in this case to 4.2 kelvin
593
01:01:56,280 --> 01:01:59,880
or to an even lower temperature
which is 1.9 kelvin.
594
01:02:00,200 --> 01:02:05,200
To do that you need a kind of thermos,
595
01:02:05,360 --> 01:02:10,520
a vessel that is well insulated
from the outside which is very warm
596
01:02:10,600 --> 01:02:12,120
with respect to the magnet.
597
01:02:12,440 --> 01:02:15,000
Basically you have a 300 kelvin difference
598
01:02:15,080 --> 01:02:18,240
which would be the same
as saying 300 degrees
599
01:02:18,320 --> 01:02:20,280
because it's a relative number.
600
01:02:20,800 --> 01:02:26,600
So then you have to make sure
the heat 'inleak' is kept to a minimum.
601
01:02:26,880 --> 01:02:28,200
So we build equipment
602
01:02:28,280 --> 01:02:31,160
which is essentially made up
of a vessel itself
603
01:02:31,240 --> 01:02:36,520
in which we can put the magnet,
then obviously we close it
604
01:02:36,720 --> 01:02:39,760
and we can access it by liquid
605
01:02:40,080 --> 01:02:42,480
which is in this case liquid helium
606
01:02:42,760 --> 01:02:44,800
and cool it down to 4.2k.
607
01:02:45,160 --> 01:02:51,200
Then we have to connect the power
to this equipment
608
01:02:51,280 --> 01:02:55,200
because obviously the power generation
is on the surface
609
01:02:55,280 --> 01:03:00,800
and a nominal 20 degree temperature
is in the hall.
610
01:03:01,040 --> 01:03:06,000
So you have to bring the current
into the magnet through this vessel.
611
01:03:06,080 --> 01:03:10,920
This vessel also helps us make
the interface
612
01:03:11,000 --> 01:03:13,600
between the magnet and outside.
613
01:03:13,920 --> 01:03:17,800
And then obviously we have
all the information coming out
614
01:03:17,880 --> 01:03:24,680
which is in the form of wires
and we plug them into
615
01:03:24,760 --> 01:03:30,080
and then we have a control room behind us
616
01:03:30,160 --> 01:03:33,760
where we get the information visible
on computers in a graphical way,
617
01:03:33,840 --> 01:03:36,520
in such a way
that we can analyse it later on.
618
01:03:36,600 --> 01:03:39,440
So that is essentially
what we have here behind me
619
01:03:39,520 --> 01:03:44,320
and basically you have three test stations
of this type,
620
01:03:44,400 --> 01:03:50,400
so three units, which are nearly
independent one from another.
621
01:03:58,800 --> 01:04:01,200
Well, my whole family is here
622
01:04:01,280 --> 01:04:04,440
because I have to say my husband works
at CERN,
623
01:04:04,800 --> 01:04:09,800
my husband works in the same area as me,
so also magnets.
624
01:04:10,240 --> 01:04:14,800
And ok, that's life,
we have a three year old child
625
01:04:14,880 --> 01:04:19,840
and she goes to the kindergarten
at CERN.
626
01:04:19,960 --> 01:04:22,440
So in the morning we come
as a family to CERN
627
01:04:22,520 --> 01:04:26,000
and are dispatched
all over the three sites:
628
01:04:26,080 --> 01:04:29,800
My husband works in the French area,
629
01:04:30,280 --> 01:04:34,480
I work between
the Swiss part and the French part,
630
01:04:34,560 --> 01:04:35,960
still in French territory,
631
01:04:36,360 --> 01:04:39,720
and my daughter is on the Swiss side
in kindergarten.
632
01:04:41,920 --> 01:04:42,760
Yeah.
633
01:04:43,160 --> 01:04:46,000
My husband also has another son,
634
01:04:46,600 --> 01:04:48,920
he's in the control room.
635
01:04:49,880 --> 01:04:55,280
I also have a brother-in-law
636
01:04:55,600 --> 01:04:58,640
in the ATLAS detector,
637
01:04:59,640 --> 01:05:05,080
so we are really all a family.
638
01:05:08,960 --> 01:05:09,800
Well,
639
01:05:12,840 --> 01:05:16,720
when you say we have to leave
some space for the imagination,
640
01:05:16,800 --> 01:05:20,720
you assume that what we are doing
is enough to understand the world,
641
01:05:20,920 --> 01:05:23,440
how the universe works, I'm not so sure.
642
01:05:23,560 --> 01:05:24,520
I think that...
643
01:05:25,600 --> 01:05:31,080
We are in a territory where we are
644
01:05:31,160 --> 01:05:34,360
so close to understanding
the complete picture
645
01:05:35,520 --> 01:05:38,080
that it has become very,
very hard to improve.
646
01:05:39,080 --> 01:05:40,880
I'm not at all convinced
647
01:05:40,960 --> 01:05:46,440
that the big steps we make
648
01:05:47,000 --> 01:05:48,680
are big enough
649
01:05:50,080 --> 01:05:54,200
to get rid of the space
that remains there.
650
01:05:55,040 --> 01:06:00,840
I think we're on the top
but now it progresses very slowly.
651
01:06:01,560 --> 01:06:03,880
I think we are still far away,
652
01:06:04,000 --> 01:06:07,080
I'm not sure it will come next year
653
01:06:07,680 --> 01:06:12,080
where we explain Higgs
and the dream is real.
654
01:06:12,160 --> 01:06:18,400
No, I think we will find elements
that will bring us closer,
655
01:06:18,480 --> 01:06:23,560
that's the idea, I believe,
656
01:06:23,640 --> 01:06:27,960
but I'm not convinced that
we will understand the complete picture.
657
01:08:13,600 --> 01:08:17,760
You might know there is a principle
called the Anthropic Principle
658
01:08:17,840 --> 01:08:20,760
which says nature and the laws of nature
659
01:08:21,160 --> 01:08:27,720
were designed only to make it possible
for humans to exist.
660
01:08:29,480 --> 01:08:32,000
But I doubt.
661
01:08:33,440 --> 01:08:38,920
Of course, we also realize
that science and physics
662
01:08:39,000 --> 01:08:44,720
is only one perspective
of understanding reality and nature.
663
01:08:45,320 --> 01:08:50,080
I had a long discussion here
with the Pope, when he visited CERN,
664
01:08:50,680 --> 01:08:54,200
not the present or previous Pope,
it was John Paul II,
665
01:08:54,280 --> 01:08:58,000
who visited the CERN.
666
01:08:58,720 --> 01:09:00,440
I discussed with him,
667
01:09:00,680 --> 01:09:07,080
can there be a conflict
between science, physics, and religion
668
01:09:07,920 --> 01:09:11,480
and we agreed, no,
there cannot be a conflict.
669
01:09:12,560 --> 01:09:13,520
He agreed to that.
670
01:09:13,920 --> 01:09:19,960
So I asked him, if you agree
why don't you rehabilitate Galileo?
671
01:09:26,800 --> 01:09:31,240
I said, look, if you have a plate,
a dinner plate,
672
01:09:31,920 --> 01:09:34,760
and you look at it from the top,
you would say it's a circle.
673
01:09:35,360 --> 01:09:38,480
If you look at it from the side,
you wouldn't say it's a circle,
674
01:09:38,560 --> 01:09:39,840
you would say it's a line.
675
01:09:40,080 --> 01:09:46,640
So they are two conflicting perspectives
and you could ask forever
676
01:09:47,040 --> 01:09:48,600
'Is it a line, or is it a circle?'
677
01:09:49,520 --> 01:09:53,360
So that's what religion
and science does with reality,
678
01:09:54,040 --> 01:09:57,040
they are looking at different projections
of reality.
679
01:09:57,600 --> 01:10:03,760
They see it differently
680
01:10:04,280 --> 01:10:07,520
but they are two projections
of the same reality.
681
01:10:10,440 --> 01:10:14,480
It takes a long time to clarify
a certain concept.
682
01:10:14,840 --> 01:10:16,880
How do we define something.
683
01:10:17,240 --> 01:10:21,120
The real imaginative nature of science is
684
01:10:22,000 --> 01:10:24,800
in creating a consensus
685
01:10:25,240 --> 01:10:28,440
which is necessary to find the laws
of nature.
686
01:10:29,120 --> 01:10:31,280
Maybe these concepts are not unique,
687
01:10:31,360 --> 01:10:36,880
there might be other ways
to describe nature by different concepts.
57551
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.