Gabriela Gonzalez So we took about four months of data.
Because the signal happened so early, we didn't want to wait until the end of these four months
before telling the world about it.
We needed to be sure.
We needed to do our analysis right, so we decided that one month of data would give
us enough confidence to do that.
And those are the results we present.
We are analyzing the rest of the data.
We haven't seen anything that contradicts anything that what we present for the analysis
of one month, and we'll tell you more when we finish, hopefully in only a couple of months.
It shouldn't take us--
Geoff Brumfiel Do you have other candidates?
Gabriela Gonzalez We always have coincidences.
The questions is how significant the coincidences are.
We have had coincidences in initial LIGO, too, and they were significant compared with
the expected background in the instrument.
So, that's what we are analyzing now.
Dr. France Córdova So, there's a nice, careful answer for you.
David Reitze Gee, it didn't even sound rehearsed.
Dr. France Córdova Can, do we have a microphone?
Great.
Okay, please.
Rachel Courtland Rachel Courtland, with IEEE Spectrum.
I was wondering about the criteria for definitive collection, detection.
So, how do you quantify your confidence in the signal and is there any doubt in your
mind that this could've been just noise?
Gabriel Gonzalez Well, we, in the analysis that we do to convince
ourselves, we calculate a significance of the signal.
Sometimes people like to hear the significance in sigmas, and this we can only put a bound
on this, and, again, the details are in the paper and that's a bound of five sigma.
I like better to measure the significance on how often this coincidence could happen
by chance.
And our estimate is that this didn't happen by chance in any, more often than once every
200,000 years.
So, we are very, very confident this is real.
David Reitze Yeah, this, this event is so statistically
significant that we can't actually put a confidence level on it.
We can only put a lower bound on a confidence level.
It is great than 5.1 sigma, which is five point, five sigma is the gold standard for
statistical statements.
It's much better than that.
Dr. France Córdova All right, yes.
Tracy Watson Tracy Watson, USA Today.
You said earlier, Dr. Weiss, that this shows that the field equations work.
So, does this mean that your, you've validated a remaining corner of general relativity and
did it need validating?
Because I've heard opinions on both sides.
Thanks.
Kip Thorne Yeah, so, the.
Rainer Weiss Go, go.
No, no.
Go ahead.
Kip Thorne I'm the theorist.
Rainer Weiss I know you're the theorist.
You better talk.
I'll say something also.
Go ahead.
Hear the authority.
Listen to the authority.
Kip Thorne He likes to dump on theorists, but I can at
least play the theorist for a few minutes.
Rainer Weiss Please.
That's your job.
Kip Thorne So, there was one regime in which general
relativity had never been tested, and that is the regime where the warping of space time
is so strong and it's highly non-linear and it is changing very rapidly with effective
speeds near the speed of light.
We have never had any tests in that regime.
This observation tests that regime beautifully, very strongly, and Einstein comes out with
beaming success.
Rainer Weiss I can't improve on that.
Dr. France Córdova And that's from than T in MTW, [] Thorne and
Wheeler which is the bible for all graduate students on general relativity, so great answer.
Yes.
Patrick Tucker Thank you.
Patrick Tucker with Defense One.
Congratulations on this amazing discovery.
I wonder if you could talk a little bit about the potential applications of it more terrestrially
in terms of, perhaps, the electromagnetic spectrum and better understanding the electromagnetic
spectrum, perhaps governing it here on earth.
Thanks.
Rainer Weiss Can I try that.
Let me give you an example.
If I understand your question right, you're saying, what does this add to what we learn
in astronomy by electromagnetic methods?
In other words, I'll give you a wonderful example.
As you now have learned, these gravitational waves are very hard to detect.
That has also a tremendous advantage for doing astronomy in an interesting way.
If they're very to detect, that means they don't interact very much with anything else.
We had to build this fancy apparatus to be able to even see these things.
So, that says something very important.
For example, if we ever have, lucky enough to have a supernova in our own galaxy, or
maybe in nearby galaxies, we will be able to look at the actual dynamics of what goes
on inside the supernova.
We will, because we are seeing the, the strain fields we're seeing come from accelerations
inside that star.
Now, you could not do that with electromagnetic astronomy, because there's plasmas, there's
all these other things that scatter the electromagnetic radiation.
The gravitational waves, on the other hand, come right out, totally unimpeded.
And so they are, you know, nothing touches them.
And so consequently you really find out what's going on inside of systems and that's a thing
that I hope will make vast new progress in understanding all sorts of phenomena in astrophysics,
that you can look at without any perturbations, due to the propagation process itself.
I don't know, Kip may have, or all of us here have other opinions.
I mean, they have more things to add to this, but that's been one of the big things that,
with this became, and now it had become, successful.
It's going to open up different ways of looking at phenomena you already know.
Dr. France Córdova Let's see, do we have a microphone?
There's a gentleman back here, okay, sure, why don't you shout out?
Tom [] Again, congratulations.
Tom [], [] Television.
I'm wondering if anyone could speak to the three dimensionality of these waves?
Number one.
And number two, do you expect at some point in the future to put out a compilation of
sounds of the universe?
Kip Thorne The three dimensionality, the waves, as I
think was discussed a little earlier, of course, they propagate from a source that's very far
away, so by the time they get here, their wave fronts are very, very flat.
But there's, it's just segments of a sphere that surrounds that source that's 1.3 billion
years ago.
As the waves go by, they don't do anything to anything, longitudinally, in the direction
they propagate, but as Rai described with his beautiful green mesh, they stretch and
squeeze space transversely.
So it's a two-dimensional action of the wave, orthogonal to the direction the wave propagates.
And LIGO was designed to measure precisely that.
David Reitze And to follow up on that, yes, we will be
issuing an album of the greatest sounds and gravitational wave detections over the next
ten years or so.
Dr. France Córdova All right, we have two questions here, yeah?
Calla Cofield Hi.
Hello, Calla Cofield with space.com.
I was just wondering if you could talk about LIGO's ability to pinpoint the location of
these objects and how that might improve with Virgo, and possibilities with some of these
things for collaborating with detectors in the EM spectrum.
Gabriela Gonzalez Yes, as we mentioned earlier, the more detectors
you have in the network, the better off you are for localizing the sources, and that's
very important.
With only the two LIGO detectors, the ninety percent confidence area we had for this source
was six hundred square degrees.
That's just impossible to cover with telescopes.
You need too many.
So, with more, with Virgo, we will have better localization.
We need more than that, so we will have that with KAGRA and hopefully LIGO-INDIA.
That localization is important not just to know more about the source and where they
lie, but also for the follow-up in the electromagnetic spectrum.
And that we began doing already in our 2010 latest run, because there were the three,
the two LIGO detectors and Virgo, so we had some localization information and we were
sending alerts to astronomers, so we could follow them.
Of course we didn't have any real detections, so this was all an exercise.
But we had, had agreements now with more than sixty groups, more than twenty five groups,
had astronomy groups, had ability to follow up these triggers.
We did tell them one of the things we weren't, we were preparing in the engineering run and
we didn't have quite ready yet, was the automatic alert system that tells us immediately that
we have a gravitational wave and then lets us tell the astronomers about that.
So it took us, it took us a day and a half, almost two days to send that alert.
But since then, during the science run, we have been sending alerts to astronomers.
Again, we only learn about the significance of the candidates much later, so sometimes
we tell, oh, well, that wasn't quite a significant coincidence, this one was.
But we have been doing that in this run, even though we have poor localization, because
of only two detectors.
We will be doing that in the next runs with better and better localizations.
So, again, it's a new window opening.
David Reitze And, can I follow up on that just a little
bit?
I think what's also really critically important here is the fact that gravitational waves
give you one view of a violent event, all right, and for the black holes that we saw,
we don't expect to see any E&M radiation.
But if you have binary neutron stars, for example, and they collide, they do the same
dance that I showed you in the movie with the black holes.
They should produce huge amounts of electromagnetic radiation and if you could, and gamma rays
down to radio waves, every, the whole spectrum.
And if you could capture, you know, using first the gravitational waves from LIGO, Virgo,
KAGRA, INDIA, when we get them all online, and quickly tell all the astronomical partners
and let them bang their telescopes, their satellites, their x-ray satellites, their
optical telescopes, on that source and see it in the E&M spectrum, you've now got a very
complete picture of this kind of event, and that's huge.
That, that, when that happens, that'll be, I think, the next big thing in this field.
Alan Boyle Alan Boyle with GeekWire.
I, now that the news is out, can you talk a little bit about the rumors, the process
that you went through?
You're sitting on one of the biggest secrets in the world of science and watching all this
play out.
David Reitze Well, how secret was it?
Gabriela Gonzalez You know, the facts are so beautiful.
The signals are so real, so nice, that why would you talk about rumors now?
Let's talk about []. Doesn't matters.
Dr. France Córdova All right, so we'll just have one more question.
I'm sorry.
Well, we'll have two more then.
We have first here and then we'll let Lisa, the ground-based Lisa, ask that, the last
question.
All right.
[]: Hello, my name is [] from China.
I'm a journalist with [] Media.
My question is that what's your, what's your discovery's influence on your competitors?
You know, there are other teams are looking for gra, for this.
And now, you won the game, and do you think, and do you think other team need to adjust
their research target?
And what are the jobs left for them?
Thank you.
Gabriela Gonzalez We are very, very proud in this field of being
collaborative, rather than competitive.
So, with Virgo, for example, we don't compete to see who gets a detector first, who gets
a signal first.
We put the detectors and the scientists and the data together.
There are other windows and some people have talked about the race to detect gravitational
waves, from the cosmic background, from the pulsar timing, which is also supported by
the NSF, from LIGO.
We don't, we don't believe in races.
I want to see all these windows open as soon as possible.
It doesn't matter who gets their first, second, third.
We all want to be there.
Rainer Weiss I'd like to draw an analogy, I mean, because
that's, it's, that is not a very, I mean, it's a question, but I know it's got more
to do with emotion than it has to do with reality.
And the thing that's important is just think about it in the other way around.
Here we have radio astronomy, we have infrared astronomy, we have optical astronomy, we have
UV astronomy, x-ray astronomy, and gamma ray astronomy, and now neutrino astronomy.
Well, that's a little different from the others.
All of those, when one starts looking at an astrophysical phenomena, give you different
information and that's what ultimately has led to finally understanding some very complicated
things in our universe.
You have information at different energy scales.
That's exactly what we're hoping will be and, I mean, just confirming what Kip said earlier,
and what Gaby has said right now, this is not supposed to be competitive.
It's supposed to be something that lets the science that's going on be more understandable.
You're getting more bang for the buck if you can get all these other wavelengths operating.
Dr. France Córdova Let's remind people how many authors are on
this paper?
David Reitze One thousand and four.
Dr. France Córdova Now, that's a collaboration.
All right and for our last question, and I'll say after this question, then you should,
our presenters will all stay here in the room.
We have the room for some time and so you can have private interviews with them, as
private as you can make in a room like this.
Gabriela Gonzalez And, France, if I may, there are many scientists
from the collaboration here, too.
I will ask them to stand up, so they, journalists can ask them.
We have all sort of expertise, instrument people, data analysis people, numerical people,
everybody.
So, please ask questions, not just of us, but everybody.
Dr. France Córdova Yes, very good point.
As I look around the room, I see we have Nobel prize winner, John Mather, from Goddard Space
Flight Center with us today and we of course have the leaders of, that I introduced earlier
from our collaboration countries.
So, Lisa, the last question, please.
Lisa 150 years ago, when electromagnetic waves
were discovered, their uses were unimaginable, like communications.
If we all open our mind, what do you think this gravitational waves would, discovery
would mean to humankind 200 years from now?
Gabriela Gonzalez That's for you.
David Reitze And actually, Kip, after you go, I'm going
to take it in a, probably in a different direction, but go ahead.
Kip Thorne Why don't you start?
David Reitze Okay, all right.
So, who knows?
I mean, when Einstein predicted general relativity, who would have imagined that we use it every
day when we use our cellphones, you know, for GPS localization?
I think one of the things that's important here, and we haven't really talked about it,
but I think it's, it's important to say the underpinnings of all this is science, engineering,
and technology.
So, Rai talked a little bit about the lasers we developed, the group in Scotland led by
Jim Hough and Sheila Roe [ph] and that discovered, or that put together the suspensions that
we use, Bruce Allen from the AEI that developed really, really sophisticated computing and
I keep going on and on and on.
There's a lot of technological spinoffs that comes out of this, and I think that is, in
the near term, where this is going to go.
In the long term, who can predict?
Who can predict?
Kip Thorne Let me just have the last word as a theorist.
David Reitze You always get the last word.
Kip Thorne Kept my mouth shut.
That's obvious.
When we look back on the era of the Renaissance and we ask ourselves, what did the humans
of that era give to us, that's important to us today?
I think we would all agree it's great art, great architecture, great music.
Similarly, in a few hundred years, when our descendants look back on this era, and they
ask themselves, what are the great things that came to us, culturally, from this era?
I believe there will be an understanding of the fundamental laws that control the universe
and an understanding of what those laws do in the universe and exploration of the universe.
LIGO is a big part of that.
The rest of astronomy is a big part of that, and I think that cultural gift to our future
generations is really much bigger than any gift in any kind of technological spin off
or ultimate development of technology that may be connected to this.
But I think we should be proud of what we give to our descendants, culturally.
Dr. France Córdova Perfect way to end it.
Thank you.
So, our great thanks to all of you for participating in this momentous occasion, and thank you
to Dave Reitze, Gabriela Gonzalez, Rai Weiss, and Kip Thorne.
That's it.