Transcriber: Diana de Vega de Ceniga Reviewer: David DeRuwe
February 21, 2016
was the first day we all celebrated
the International Day of Women and Girls in Science:
science, technology, engineering and math, or STEM.
This had a great response.
In Twitter, this was the second most popular trending topic that day.
But February 21, 2016, for me, was a special day for a different reason.
I was in Washington, D.C. in the National Press Club
with a small number of scientists representing a great number of minds,
about to make the announcement
of the discovery that had been a hundred years in the making:
the first detection of gravitational waves.
It was an amazing moment.
That was the top trending tweet that day.
(Laughter)
The announcement was about two black holes
that had been dancing an accelerating tango, a billion years ago.
They were rotating around each other faster and faster,
bending furiously this space-time around them,
producing gravitational waves,
and then merging at about half the speed of light
into a single black hole.
In that last fraction of a second,
they emitted a large amount of energy in these gravitational waves,
more energy in that fraction of a second
than the whole visible light in the Universe.
It was great!
(Laughter)
Now, you're probably thinking: gravitational waves?
Are those waves of light?
No, they're waves of space-time.
They travel at the speed of light, but they are waves of space-time.
What is space-time?
It's at the basis of Einstein's theory of general relativity,
which is a theory of gravity, just like Newton's.
It says that masses - all the masses, all of us -
live in a fabric of space-time.
A fabric that's flexible and dynamic,
and the masses distort that fabric and follow that curvature.
That explains why the Sun and the Earth - and the Earth moves around the Sun
and how the planets move around the Sun, just like Newton did.
But it also predicts that when the masses move,
they're going to produce these gravitational waves
that are like ripples in a pond.
Einstein himself predicted the existence of these gravitational waves
in a paper in 1916, a year after publishing the theory of relativity.
"But," he said,
"these gravitational waves are so tiny, so small,
that they will never be measured."
Einstein was wrong on that:
We did measure gravitational waves in 2015.
And that was the effort -
working, designing, building, operating and analyzing the data
of two big observatories in the US, the LIGO Observatories -
there is one in Washington state,
another in Louisiana, here -
and in these two observatories we can measure Einstein's space-time.
This is the work of hundreds of people,
men and women, who have worked on this for many decades,
people from all around the world.
What happens at these observatories is that we have lasers that travel
in two perpendicular directions in vacuum tubes four kilometers -
two and a half miles -
and come back and tell us about differences in distance
between mirrors that reflect the laser -
these mirrors being very, very carefully isolated from the motion of the ground.
This is how we measure Einstein's space-time that changes these distances,
and this is what we did in 2015.
Now, that effect was very, very small,
the effect that these black holes,
these huge black holes emitting that huge amount of energy produced.
On that, Einstein was right.
How small a signal we measured that September 14, 2015?
Let me tell you: it was smaller than an atom.
An atom is 10 to the -10 meters.
We measured something 100 million times smaller.
The smallest nucleus of an atom is a proton and that is still too big.
We measured four parts in a thousandth of a proton diameter.
That was the precision we had for measuring
over this four-kilometer baseline.
No wonder Einstein didn't think these things could ever be measured!
There we were, February 11, 2016,
back in Washington, D. C.
We were in front of journalists,
we were there.
France Córdova, the director of the National Science Foundation,
she was presiding the press conference.
There were four scientists there:
Dave Reitze, the executive director of the LIGO laboratory,
Kip Thorne and Ray Weiss, two pioneers of the LIGO project
who have been working on this for more than 40 years,
and myself, as spokesperson of the LIGO collaboration,
representing more than 1,000 scientists in this collaboration.
When Dave got to the podium and said:
"Ladies and gentlemen, we discovered gravitational waves,
we did it!"
everybody broke into applause and some tears.
We had been working on this so hard, for so long.
The reaction to this announcement was incredible, not just from journalists-
we were in the front pages of newspapers all over the world -
but also from the public!
Gravitational waves were everywhere!
In ads, in cakes, in dresses - these are gravitational waves -
(Laughter)
It was so nice.
But there was one comment said a few times
that had a strange effect on me.
Some people said it was so nice to see two women at the podium,
and two Latinas too!
Why was that so curious?
Well, because there are few women in science, especially in physics.
Now, I'm a numbers person, so I am showing you the data.
This plot shows the fraction of women earning bachelors in STEM
over the last 50 years.
And the numbers started small,
but they grew, and now there are many sciences
in which the degrees are awarded to women between 40 and 60%.
For example, in math, in chemistry, in biology.
However, in physics and engineering, it's only 20%.
And it hasn't grown in the last several years.
20% is a small number.
Science and technology, we all know, are very important.
They are the drivers for progress and quality of life,
but more than that, they are drivers for human rights, human dignity,
eradication of poverty, protection of the planet,
and we cannot do the best science
if we don't find all the talent of potential scientists.
The world needs science today more than ever,
and science needs women.
And it's not that girls are not interested in science.
In high school, in elective physics classes,
close to 50% of the students are women.
How can we detect tiny gravitational waves
but not detect and inspire those high school women
to follow a physics college degree?
Perhaps, because when you think of a physicist,
you probably think of Einstein,
(Laughter)
Doc Brown in "Back to the Future."
(Laughter)
Sheldon Cooper in "The Big Bang Theory"?
(Laughter)
What do these people have in common?
Well, they're all men, but they're geniuses too,
they're awkward, they work alone, they all have bad hair.
(Laughter)
These are not inspiring figures for a career in physics,
especially for high school women.
When I was in high school in Argentina, I wanted to study physics
because I thought that physics could explain everything,
everything from atoms to planets to the Universe.
I wanted to learn to explain everything.
I didn't think about becoming a scientist, certainly not about becoming an Einstein.
Perhaps that's why I wasn't intimidated and followed a career in physics,
and I'm very glad I did.
In my career, I have very often been seen as one of the "others,"
as opposed to "them":
I was a woman, I was a Latina, I'm an immigrant,
I was the first woman physics faculty here in LSU,
I was the first female spokesperson of LIGO,
but I never felt different,
I never felt a woman scientist,
and after interacting with me, people stopped seeing me as different.
I was one of them already.
We physicists are not all geniuses, we are not all awkward,
(Laughter)
we come in all shapes and colors,
we are tall and short, and men and women,
from many different countries, many different cultures.
These are pictures of our young physicists in the Louisiana State University group
and the scientists in the LIGO Livingston Observatory.
These are your scientists,
not Sheldon Coopers, not Einsteins.
These are the scientists that discovered gravitational waves.
20% of women in physics in college
is a very small number.
Or is it? Do we really need more women in science?
Yes, we do!
Science is about questions and answers.
It's about finding the questions,
finding the answer,
sometimes not finding the answer that we wanted,
and then more questions arise.
And we want women
because we want the best people to do the questions and the answers.
And women are not better than men at this.
But men are not better than women either.
They are different,
and it's bringing diversity to the table what makes science progress faster.
Imagine how much faster we would have made progress in the last decade
if we had had more women in science.
That's why 20% is too small.
I am today very happy to be in the spotlight
as a woman talking about this big discovery of gravitational waves,
but I dream of a day when I'm talking to an audience
when there are enough women scientists and nobody notices my gender,
they just see another physicist.
Thank you
(Applause)
(Cheers)