Music for the Cosmos

good afternoon everyone and welcome to the second art meets science at slack lecture I'm Angela Anderson with the Office of

Communications at slack and I'm very pleased today to welcome to stage both

an artist and a scientist to converse about the ways that art and science have

influenced and inspired them but also to share with you a very special and beautiful collaboration that came about

during their first meeting at slack last October the artist is Nitin Sawhney he was just

awarded a CBE in the Queens New Year's Honours List and he's one of the most distinctive and versatile musical voices

around today he has achieved an international reputation across every possible creative medium with over 20

studio albums to his name including solo albums film soundtracks and compilations

as well as 50 scores for film and gaming he is the recipient of many notable

national and international awards including the Evora Novello Lifetime Achievement Award in 2017 most recently

he completed the entire composition of Netflix Warner's Mowgli legend of the

jungle directed by Andy Serkis Nitin is the inaugural artist of Stanford's

presidential residency on the future of the arts and I want to thank Stanford life for bringing it into slack as a

part of this residency Nitin will be joined by our own Risa Wexler she is the

director of the Kavli Institute for particle astrophysics and cosmology which is a joint institute between slack

and Stanford University she is an associate professor of physics at Stanford and of particle physics and

astrophysics at SLAC and she joined Chi PAC in 2006 her work combines numerical

simulations and modeling with some of the largest existing and future galaxy

surveys which are mapping the universe to learn about the nature of dark matter

and dark energy so please join me in welcoming Nitin Sawhney

and Risa Wexler [Applause]

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[Music] I mean it's interesting because the

first time I saw this was when you were talking about it here and um I mean it

was so gorgeous because I saw it in 3d and it was it was such a great visualization that I just thought it was

bizarre to me that there wasn't any any music and I kind of felt wow it just

felt like a great opportunity so and it's it's so powerful to me and so profound to watch ionizing gas I mean do

you want to tell us a bit yeah so let me just say a little bit about the science behind the movie that that you just saw

so that that movie was taking place in

the first billion years of the universe it's during a period of the universe called rihanna's ation that's because

what's happening during that period is the movie starts kind of right at the

beginning of when the first galaxies start to form in the universe just less

than a billion years after the Big Bang and when those first galaxies start to

form the universe is filled with hydrogen gas and energy from the stars

in those galaxies actually ionizes the gas basically clears it out and and

that's what you saw in that movie that the gas sort of went from being opaque in the beginning of the movie towards

the end that sort of after about a billion years it has the gas has been cleared out by the generations of stars

that form and so it's not a very you know in a cosmological time scale for me

I work on the whole history of the universe about 13.8 billion years so for me that's a short time period for

most of us in our daily lives a billion years is a long time one of the things

you saw in that movie was that there's a there's a lot of structure in the universe so it's not perfectly smooth so

you know the galaxies form in certain regions initially and then you know later that emptier regions clear out I

love watching it with I mean this movie is especially beautiful in 3d because it

has so much depth to it this movie is based on work done by my colleague Tommy

Bell and his group and the visualization was done by Ralph Caylor who's a here at

slack and he's amazing at making these movies he has a lot of work in planetariums here and in New York so I

think actually both of these movies have shown in at Cal Academy and in New York

of the planetarium there but I love seeing it with this music because it's

sort of just it makes the wonder that you see when you watch it just so much

more visceral well thank you and so so originally this piece of music was so

this is this is one composition there's gonna be two compositions we're going to show including this one and the other

one is a totally brand-new composition but this one was an adaptation from piece that I've written called spirals

and I just felt it fitted really well actually I played it outside just here

in the inn and then what you call that area in that area outside last Sun was

here in October but it just felt like it was it just really fitted and the the

the impact on me I mean it's very interesting because there's an artist I respond intuitively to what I see him

what I feel but and and it's fascinating to me that Albert Einstein once said it

was shin Shinichi Suzuki who quoted him in 1969 saying that he once said that

the relativity came to him through his musical intuition and actually Einstein

was a was an amazing violinist and was was the chair of the Princeton Orchestra

and and he had conversations with a polymath

from India called rabindranath tagore in 1927 1930 in Berlin and in those

conversations they talked about the nature of music and and the nature of reality and they touched upon so many

different ideas from theology to to physics to to music to philosophy and I

just found it was such a an interesting kind of those two conversations were so

interesting in in the judge supposition of science and and somebody who come

from an artist background and so for me I've always been really interested in the idea of collaborating with with

science as not as a musician yeah i mean i i i i just love the fact that putting

putting them music - you know - this i think brings it just so much more depth

and kind of just brings it opens up you

know a different kind of appreciation of its beauty yeah I think it's it's kind

of well thank you for saying that but it was it was it was I was very lucky to be joined on that piece of music which is

based on a time cycle of 7-7 Bates's in 7/8 time and the musicians who I was

joined by were Manny De Lago who's who plays with that and if you if you know

Bjork over here but he said he's a fantasy any also plays with Anoushka Shankar who's a very good friend of mine

punditji Ravi Shankar's daughter and and he's an incredible musician playing

what's known as the hand pan and I really love the way he plays and it just

felt really appropriate but also the incredible bansuri which is an Indian

bamboo flute played by Ashwin Srinivasan who who I also got to play on the music

died if remotely which is the Netflix film and and he he just gives such depth

to his expression meaning the in the way that there's such a fluid way in his in

his musical articulation that comes from that's based in Indian classical rock so

yeah I mean I was very happy to be joined by those musicians and and they really I think enhance the the piece and

how it worked hopefully with the visuals nothing yeah I mean I think there's a

this this movie in particular there's such a richness to the way you know it's

it's interesting we were talking earlier today about the interesting thing in cosmology how you have to deal with such

a vast range of time scales and length scales and actually this this movie

actually both of the movies you'll see there's evolution in time and motion

through space and so you know the span of the first movie is maybe half a

billion years the span of the second movie you'll see is closer to about 13 billion years and but even in this

period you could see there was stuff happening right there was you know this this depth of the of the gas and the and

the thickness of the gas was sort of clearing out over the time of the movie hmm and I think that sort of having a

having the music sort of brings you into that a little bit more well that's cause

I was I was just wondering is you know the person who actually created the

simulation was or visualization was Ralph kala and I'm just I was asking you

earlier about the way in which you generate the information that that all of this is based on so would you like to

explain that again sure yeah so so in

these in these simulations we start out with some understanding of what are what

is what are the basic constituents of the universe so how much of the universe is made of normal stuff like you and me

atoms basically how much is made of dark matter how clumpy is the universe like

how much stuff do you have clustered in big versus small things so there's there's

basically six or seven numbers that we hit that we use to describe all of those things basically what the universe is

made of how clumpy it is and how its expanding over time and actually in the

second movie which contains only gravity those are the only numbers that go into that plus gravity in this movie there's

a little bit more in it because what you see is that there's gas and that there's

also star formation and that actually is much more complicated than gravity

gravity is the easy part and so what you saw in this movie was that there are actually galaxies forming and those

galaxies form out of the places where you have dense regions of of matter and

then after they form they eject this energy into their surroundings um and so

that's sort of what is is happening in the in the computer and then Ralph takes

takes those simulations and turns them into these really beautiful visualizations it's incredible actually

it's interesting listening to you talk about numbers as well because when the Heisenberg talked about the about where

he quoted Pythagoras because Pythagoras originated ideas in terms of musical

ratios and understanding the intervals within music and and that was developed on by Johannes Kepler and also Vincenzo

Galilei so they they kind of took the ideas of ratios but actually in Werner

Heisenberg's concept of the universe his he talked about the perfect number being

10 because it was because it was the sum total of the first four integers of that

that we use to generate ratios in music and I kind of think it's always

fascinated me with with physicists who are able to kind of look at the nature

of music and it's in its place within cosmology and within understanding you

know harmonic resonance and people like Tesla and it's it's interesting how physics has

really kind of had a very strong kind of relationship with the evolution of music

you know and and the way I mean for example my guitar is is only tuned the way it is because of Pythagoras you know

and and so it's kind of it fascinates me that that you know there is this kind of

constant symbiotic relationship between science and music that continues over time absolutely what first got you

interested in sort of in thinking about science and its relation to music well I think I've always been interested in in

science and math since I was very small but I I mean for example we were talking

earlier about fluidity of thought and and with music I mean I was classically

trained as a pianist first but I also played a number of different things I got into playing flamenco guitar and

then I was a jazz pianist and then I was in I played table and sitar and then I was in a punk band rock band a funk man

so I kind of and I was an orchestra so I was kind of you know but I was always experimenting and my whole thing was

that I always thought of music as a place for patterns we were talking about pattern recognition and finding finding

relationships with different ways of thinking about music so for example with with the way in which music is taught

quite often within the classical world it will be very much like a news reader might read

the news you know perfect kind of diction and looking or in some places

and and you know reading reading from an autocue but it's about great enunciation

but not necessarily understanding or being able to improvise around the subject that they're talking about and

so if you take away the autocue maybe they might struggle to explain what it exactly was that they were talking about

just before and but but it's very precise in the way that they have been trained to explain whereas for example a

stand-up comic will actually improvise around words and improvise around ideas and so for me that's the difference

between a classical musician and jazz musician so I kind of you know I I was always looking at how you become more

fluid and it was the same with mathematics when I was very I got frustrated listening to people

reciting times tables which is what they did when I was growing up I don't know how they teach maths now in schools but

but they they would be very much about reciting from memory as opposed to

learning how to calculate I never thought that was mathematics and in the same way I didn't really think that I

was engaging with music until I started being playful and I think it's you know

with with all the scientists and with all the people that I've admired whatever sphere of knowledge they come

from they're playful and they they actually like to look at a subject from

many different angles and so I think music and science from that point of view will always felt very much coming

from from the same place to me yeah I think it's it's one thing that is so fun

actually about physics that we also have these very clear rules about how the

universe works that we're trying to figure out but there is a lot of play and there's a lot of trying to

understand how pieces fit together trying to connect one thing to another

thing to see how they might relate and to see if you might learn about one thing from the rules that apply to

another thing I think it is it I think one of the things that's great about

sort of thinking about art and science and their connection is this is this

similarity between sort of the interaction between rules and sort of

creativity yeah and you know we talked about yeah I was also a classically

trained ballet dancer which also has rules but then a lot of playfulness now

and can't have a lot of creativity as well that's right I mean it's it's interesting with that as well I mean I

work a great deal with dancing and actually Arkham Khan who I work with a lot it came over here and was working

with your I think cybernetics Department and but he's he's very interesting that

he comes from a discipline in India Kolkata dance and Catholic dance is

based on a treatise that was written 200 BC called the Natya Shastra which looks

at the vocabulary of of lots of different disciplines work

together within the arts so for example you will have catholic dancers having

the same vocabulary of expression as as a musician so they will they will have

these spoken patterns for example that will be based on time cycles I mean I was talking about 7/8 pattern there a

time cycle within Indian classical music could be a 10 a 10 for pattern which in

India would be would be clapped out like this 1 2 3 4 5 6 7 8 9 10 and you keep

this going then within that you have mathematical structures so you might have what's known as a T hi that

actually explains in an oral tradition how to play the percussion so one

pattern or one phrase might be did they get the gut again da da da and if you say that three times it has to land on

the first beat of the next cycle so they figured the gut again thought it did to get the gut again look at the gut again

da da da so it lands on the first play and it gets more more complex and it can be extraordinarily you know difficult

and sometimes dances and doublet players will be able to improvise well they

should be able to within within those rules so rules are very important you

know within Indian classical music as well as western classical music and I think all these different traditions of

music around the world have kind of really evolved around constraints that I think really defined their identity

mm-hm yeah it's so it's so interesting this sort of interplay between constraints

and what can happen in the presence of them yeah absolutely I mean the the

mathematics that generated that you know as well I mean is gonna be is you know that's that's interesting but ultimately

what comes out something playful yeah and it feels like you know a very creative kind of product yeah which is

which is great and and so what drew you originally to to science I guess I was

really just driven by the questions I found you know the possibility to think

about what is the universe made of how did it evolve how did we get from the earlier moments to being here today to me those

were the most compelling questions real question yeah really small questions and I've been really

lucky to be you know this field has just been in this flourishing Renaissance

it's so data rich for you know the last 20 years and I think we're almost guaranteed to have a similarly exciting

20 years you know we went from you know when I started graduate school we didn't know these basic questions how much

matter is there in the universe and that's something that we now have measured very precisely so when I was

talking about the age of the universe we talked about this at the age of the universe we now know it's about 13.8

billion years with a narrow bar of 20 million years so Nitin said earlier I

was 10 years out thirty point seven point seven you know close enough but

actually our measurements are so precise that we can actually say that it's not 13.7 it's thirteen point eight so to me

that's that's really amazing that's in the last ten years you just that's just another yeah absolutely and and so is

this really interesting thing where we're measuring very precisely these numbers that tell you what is the

universe made of how did it evolve on large scales and we can we have a theory that essentially explains everything

that happens on the universe on large enough scales like much larger than the scale of a galaxy but there's lots of

scales that matter and so once you get down to smaller scales other kinds of physics matters more and more and you

start to care about how do stars form what happens when black holes eject

energy and into their surroundings how does that impact the gas what happens when these stars impact the gas and and

all of those are really complicated computationally and also challenging to

observe but you know we're making good progress so you know it's very exciting

I mean I get very excited as well that's seeing all this I mean in my kind of

very crappy kind of amateurish way I read the new scientists everywhere can i I've been amazed by the photograph of

the black hole emerging and then a then also the Frankie go Rena experiment

with quantum physics just kind of re calibrating how we perceive everything

and it's it's just so exciting seeing how quickly you know our perception of

everything can consist it must be difficult how do you keep up with everything yeah I mean it is it is uh I

feel really lucky to be in this field where you your mind is kind of blown all the time I mean it was you know really

incredible - I think for everyone to see this picture of a black hole and and we really are discovering things at such an

amazing rate I mean the fact that we've now you know seen thousands of planets outside the solar system that's all

essentially within the last ten years so it's really incredible I think and and

one of the amazing things is you know how all of these different scales are are connected so you know maybe maybe we

can go on to the next movie and one of the so the the next movie that we're

going to see is as I as I mentioned it's essentially the evolution of a piece of

the universe that we're watching almost the whole history of the universe starting about about half a billion

years after the Big Bang until today and the interesting thing is what goes into

this is the seeds of structure that actually came from quantum fluctuations

in the very early universe in the first tiny fraction of a second the universe expanded really really rapidly and the

quantum fluctuations basically became real and and created the matter that

that we see and so that's what we're going to watch here this movie is actually just gravity but you'll see

something about where the galaxies form so let's go ahead and watch this

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[Music] that's an amazing visualization I have

to say that that one was very emotional when I first watched it I think there was something really touching and

profound and maybe it's because it's kind of if it's black and white and then you have these incredible lights and

then when you realize that each light is a galaxy it's a very profound realization and is there's something

about it the kind of I think underlines our how small we are

yeah and you feel kind of in awe watching it I think I did when I first saw it particularly again 3d by it was

it just really felt very immersive and experience to say yeah I love this movie

I've watched it probably hundreds of times and this is the kind of simulation that my group does but I can never get

tired of it and I also really appreciate what the music brings to it it sort of

highlights the power and there's this there's this sense in the music there I I felt like there's this sense of

anticipation of like one of the things that's interesting in this movie if you if you look at it carefully as Nitin

said you know the the black strands that's the dark matter in the universe the only thing that's in this movie is

essentially what are those initial conditions that come from the quantum fluctuations basically what what are the

constituents how much dark matter how much normal matter how clumpy is the

early universe and then gravity so that's the only physics that's in there is gravity but one of the beautiful

things here is that gravity works really on a very broad range of scales so

what's interesting if you pay close attention to the movie you can see that in some regions there's like a lot of

stuff happening there's galaxies colliding there's you know matter being brought in and drawn into the galaxies

and galaxies lighting up so in this movie the galaxies are a model so in our

in our understanding of galaxy formation galaxies form in regions where you have

enough dark matter in one place and you have enough dark matter in one place you start to cool the gas and start to

form stars and that's where you get a galaxy we think every galaxy forms in this way of this surrounded by a much

larger amount of matter and and it forms you know sort of from small to big so

you know in the beginning there were just these tiny little spots and then eventually those merge and grow to

become big galaxies like the Milky Way today and what I love that somehow

somehow for me watching it this time the music brought this sense of scale

somehow to me that there are these sort of there there's quiet in the unlock

else but then action on small scales that's great and what I was going one

thing that you mentioned earlier when we were chatting with them was that that

dark matter is 85% of all matter in the universe and I I was struck by that

because it combined with the fact that a hundred thousandth of the diameter of an

atom is its nucleus where most of its mass is concentrated so I was thinking god that's just you know it's it's

incredible how how we have this perception of reality is this all-encompassing thing reality as we

know everything we can see feel touch and and yet it's interesting as well to

me that both Einstein and I mentioned before rabindranath tagore when they were talking all those years ago in

Berlin they both came to the conclusion independently that the universe was an illusion which I found quite fascinating

and on one way in one way I think it possibly was convenient educational

responsibility for their lives which were quite interesting their lives and better him but I kind of think that it's

also manin years ago I went to interview and I imagine a lot of you here may know

who David Deutsch is and I went to interview Emmys a quantum physicist who was a visiting professor Oxford

University I'd read his book the fabric of reality and I was so interested by his interpretations of

Hugh Everett's concepts of the many world's theory which he came up with in the 50s you know David Deutsch had this

concept of the multiverse and he talked about that in relation to quantum theory and that the universe splits into

different possibilities I think is also based on the double slit proton experiments and and so I kind of think

it kind of fascinated me all of this because I I I think that reality is such

a fragile thing to grasp in so many ways and and so quite often I will work with

intuition over my logical brain because I think my logical brain quite often

will will kind of fool me into thinking certain things I mean jihadi the

mathematician who worked with Sri Srinivasan Ramanujan he actually talked

about the fact that mathematics was the only reality there was that you could rely on and that everything else was was

was fallible so it kind of there's something about this that kind of makes me feel like our intuition is so much

it's so kind of enmeshed with the way in which the universe how we perceive the universe and and I guess there's a

musician I'm always thinking that way yeah it's so interesting I say I find

it's one of the things that I love about the movies is it brings such different

things to different people and it also does just change your perspective on you

know you know in my daily research life I'm working exactly with data from

movies like this one but you know it's it's much more abstract you know we're looking at you know the correlation of

some objects with some other objects and comparing them you know to things we to the galaxies that we're mapping out in

the universe but what I you know that's all like much more abstract and much

more numerical and so to actually feel more what it what it looks like and when

you experience it in 3d and then when it has a soundtrack it becomes much more

visceral so I really love that about this connection I'm glad too as well

that you said visceral because for me it's it's so because it could be quite soporific

and experience to to watch something like this because it's a very it's a very beautiful visualization but I

wanted to bring out the kind of visceral nature of things colliding and and what

you said you know earlier today when you were talking about how dark matter passes through us all the time but it

doesn't actually you know it has no it has no mass but it but the idea of that

that it's that it actually is passing through us all the time and that there were these collisions taking place that

was something that I kind of found amazing and and really inspiring musically which is why putting these

kind of crazy beats it was the back end of it to kind of give this backdrop of against all this kind of cool sound and

an orchestral sound something that felt quite quite visceral and had that feeling but um should we maybe things up

to anyone who might want to ask anything yeah let's go ahead and take questions from the audience if anyone's going me

or we can just all go I just wanted to let people know that if you do have a question you can just push the button on

your microphone in front of you Michael so I'd like to ask you about the like

the big tonal choices in the two excerpts so in the second one it's

conventional Western tonality I mean it's new music obviously but it's conventional Western tonality

it's like shhhhh mitten is the mall Dow where the little mountain stream becomes a big river at the end the first one was

really different and you said 7/8 time and you're using classical Indian modes

rather than western tonality yeah and it's really distancing so the the the

second one somehow it was something that emerges in our universe and the first one was somewhere

else well and I wonder if she would come in on on a whether I got it right and B

whether you consciously made those choices well first I didn't think thank you

first so I don't think there's a right and wrong I think it's the subjective experiences or music would be but I

think and I appreciate yours but I think I think in the first piece it's it's

interesting because you you find it from somewhere else for me it's very familiar territory and both are equally familiar

as I said I have background in classical Indian and classical western music so I just will allow my intuition to speak to

me more than anything and so yes I'm kind of using I mean I recently I wrote him Norah Torrio which we actually had

performed with National Youth Orchestra and London contemporary voices at the

Barbican and I kind of find that it's very powerful just to sometimes rely on

orchestral sounds and call sounds just to get across something quite profound and a strong feeling but then at the

same time I have a have a very strong connection with Indian classical music and that the you know ROG's to explain

what ARAG is raagh is it literally means color within Indian classical music so

the equivalent would be modal so you might have the seven modes and you have

72 basic rugs within Indian classical music which can which all have very

complex rules associated with them not just mathematically but also in terms of the intervals and the and the use of

those intervals so it's kind of these were just two separate pieces that I

kind of looked at in their own right drawing on my understanding of music from different angles but if I were to

do another 10 pieces probably each one would sound very different but it's all coming from a feeling that I would have

as a response to whatever I'm watching I don't know if that helps oh cool

for the first piece realization is also cosmic dawn do you actually know that

term art I think you're in looking down

to your music but I didn't know if that was a conscious choice or well I'm I'm

kind of familiar with them I mean with the ideas behind this because you I'd

heard really give a talk about them but I think I also wanted to kind of react

more from a visceral perspective but we were talking about it was interesting because I I was we were talking about

cosmic microwave background radiation and I I find all the bits so fascinating

because I remember when I was a kid staring at a television sets with interference on for ages

had I known at the time the 10% of that was actual cosmic microwave background radiation I would have been mind blown

and so so I kind of think there is something that I maybe have channeled

about that all the feeling of that but I think you know as I said I I kind of go

with my intuition of feeling first and then and then find where it takes me

yeah correct me if I'm wrong but I think your second piece at some point brings

in human voice to it yes can you comment on that that was really really interesting case okay yes I I mean

that's everything you heard on the second piece was me in the studio on my own in front of a computer so I'm

generating Orchestra and and voice is playing them on a keyboard so I mean to

get into it there's fantastic software now available I do write regularly focused reserved written extensively for

the London Symphony Orchestra and I've conducted orchestras but I I quite often because I'm film composers sometimes

people will ask you to mock up music before you actually go in I mean with

Mowgli for example we went in with an 87 piece Orchestra air studios but beforehand I had to mock things up so

they sound roughly like they will sound in the in the final version so nowadays there's incredible

software available there are companies like Spitfire who will who will come up

with simulations of all K of Orchestra for example they will spend ages

sampling each and every note played by an orchestra at different dynamic levels

in order to be able to play based on velocity in the way in which you're

playing the playing the orchestra on the keyboard and in the same way you can do

that we caught requires as well that choir that you heard was coming from software that been developed by Eric

Whitacre who's a well-known choral arranger and that was actually his choir

that I was playing on the keyboard effectively so the courts and the composition are all generated by me but

the sounds have been developed by software engineers and it's actually

asking a slightly different question what was the relationship of bringing the voice in terms of the evolution of the universe okay so so the voice I mean

I guess I yeah I mean I I put it towards the back end because it felt like I mean

you know our journey I mean it's actually I think it's actually

approximately perfect timing in that you know it came in maybe I I don't I don't

need to check but maybe it came in about four and a half billion years ago but I

think in terms of that kind of an anthropic feeling you know kind of I

wanted to bring that in because actually our perception of time is relative

obviously and and the way in which we look at everything is subjective so we you know we have perhaps a distorted

perspective and how importantly so maybe I kind of brought in a choir to kind of represent that I think that's probably

what my thinking was at the time was I wanted to actually bring in human voices towards the back end of it thank you

yeah so I'm really curious about this notion of frequencies and resonances and

sounds and matter in the universe from the music of the spheres to these recent

events where we were able to hear gravitational wave right and this is inspiring like that or that I understand

the black hole sounds at 37 octaves below middle C at a b-flat so I'm just

curious if you two might talk a little bit more about like not only using sound

as a tool of measurement but also these notions of scale and how to bring scale

from cosmic scale to human scale and the kind of role intuition may play in

talking about that multiverse of scales yeah as you said Pythagoras and Johannes

Kepler talked about this in you know in relation to I mean Kepler talked about it in in terms of the the the average

distance of the Earth from the Sun being a semitone and he talked about me far

you know in in relation to that so you're right there is this kind of idea but also I guess so something came to

mind as you were saying that I was just going to elaborate on yeah I mean I

think that that you know it's important to kind of look at look at how sound has

kind of you know how we've all perceive sound historically over time and and how

its how its evolved I mean recently in 2018 in August they've now discovered or

they've now talking about sound waves actually having negative mass which

amazed me so actually sound travels up which was astounded to hear but it's

kind of I had no idea of that I mean it's an incredible concept to me and so there are constantly discoveries that

kind of make me question the nature of sound and and so on I mean Tesla obviously in

terms of the harmonic resonance and what you could do with it and the power of it you know again it it makes you think

about low frequencies and how you use them and how powerful and emotional they can make you feel and I do I mean for

example even thinking about music from from the perspective of how animals

perceive sound animals perceive sound for communications survival reproduction we we actually imagine that we are

unique in that we derive pleasure from from music that's different to animals but but actually there's experiments

which show that chimpanzees have a Silla terry phase look that means that they are bothered by dissonance within music

so dissonant intervals ratios that actually are uncomfortable to them make

them make them agitated and so conversely consonant intervals will make

make them feel you know pleasure in the same way we get pleasure so this there's quite a lot of research

in zoo musicology that indicates that the way in which we perceive sound is

not just unique to humans but also it's it's within the animal kingdom but also

through people like Kaplan Pythagoras and and Galilei Galileo's father you

know that there's all kinds of research that was done a long time ago that indicated that it's fundamental to how

we you know how the universe has evolved so just I'll just pick up on a couple of

those topics and then we'll well and you know I think it is really interesting one how sound actually is a tool for

understanding the universe and the gravitational wave is a great example that you know gravitational waves are

not really sound waves but they they are something which has a frequency which

can be turned into sound waves and actually help us understand as we said like viscerally like this helps us in

some way understand you know that whoop you know which is actually you know those black holes going faster and

faster together it really is a frequency so I think that's a that's a really cool way of like taking something that

might be less visceral and and making us sort of understand what it is I think another thing that that comes to mind

that was sort of part of your question is actually how we use sound waves to learn about the universe there's a

really very cool thing about sound waves in the early universe that actually as

as the normal matter at is interacting with photons it leaves this sound wave

in the early universe that actually leaves an imprint on the distribution of galaxies it goes by a funny name called

baryon acoustic oscillations and and it really is based on sound waves in that

early part of the universe and that is actually going to be over the next few years one of our amazing tools are using

using the spectroscopic survey we were talking about called desi to actually figure out what the universe is made of

and how dark energy is evolving it's actually using the imprint of those those early sound waves so it's very

cool so I think we're gonna have to stop I want to mention that actually maybe I'll just call on Laura ooh hi my name

is Laura Evans from Stanford live and I would like to tell you about the concert we are having on well we have two

concerts featuring Nitin Sawhney on Friday night he's collaborating with the Stanford Symphony Orchestra in some of

his original compositions it will be really very nice and then on Saturday we have a program called music in motion

also at Bing concert hall at 7:30 and it's a showcase of artists thinking

about art and technology these films will be shown and Nitin will be in conversation with NGO Wong a professor

up at Karma and we're also featuring kaki king who is a guitarist who does

things with visuals projected onto her stationary white guitar and those at her

her playing generates the imagery she's also she's very interested in data

visualization and then we will have a piece called alternating currents which

features a dancer interacting with a Tesla coil so please come it will be a

wonderful event so thank you all for for joining us today and I hope that you'll stay for

there's a reception just outside the auditorium thank you so much

[Applause]

[Music]