LONDON CITY NIGHTS

Friday, October 26, 2012

The Sensual Universe – Sound – “Harmony in the Universe” by Jean-Phillipe Uzan, 25th October 2012

Friday, October 26, 2012 - by londoncitynights · - 0 Comments

In space no-one can hear you scream.  Or anything else for that matter.  So how do you give a lecture examining sound in space?  I found out last night at the latest ‘Sensual Universe’ lecture at Imperial College London, a public lecture series which takes the five senses of the human body as its starting point.  Every single one of these lectures so far as been fascinating, and also somewhat intimidating.  Astronomy and astrophysics are a bit outside of my area of expertise, but nonetheless each and every speaker so far as presented their subject clearly, entertainingly and compellingly.  Previously in the series I’ve see Dr Saralyn Mark on the subject of ‘Sex in Space’, and Dr Subhanjoy Mohanty on ‘Beer in Space’, covering touch and taste respectively.

Tonight’s speaker was Prof Jean-Phillipe Uzan, a French cosmologist and director of research at the Centre National de la Recherche Scientifique and the Institut d'Astrophysique de Paris.  He works in theoretical physics, studying the makeup of cosmology at the very beginning of the universe, in particular cosmic background microwave radiation, the topology of the universe, scalar tensor theories and alternatives to general relativity as well as writing six books and hundreds of scientific papers.  As far as cosmologists go he comes across as someone dedicated to making science understandable to the general public.  To this end he’s written two children’s books, and made it a mission to explain cosmos to the public through music and art.

Prof. Jean-Phillipe Uzan

It’s the meeting point between science and art that’s the focus of Uzan’s lecture.  The two can sometimes seem impossibly at odds with each other; art being almost entirely subjective and science ideally being objective.  But when it comes to demonstrating how the universe works, scientists either turn to or become artists to best communicate their ideas and discoveries.  Conversely, many artists find inspiration in the poetry of the cosmos or appreciate the similarities between pure mathematics and music. 

Uzan begins by explaining that to perceive the universe, humanity needs to “find new eyes”.  Sight is perhaps our primary tool for understanding the universe, but when it comes to viewing space, it can only show us a small part of the picture.  Much of astronomy involves observing the universe through different parts of the electromagnetic spectrum, from gamma rays, though x-rays all the way through ultraviolet, microwaves and radio waves.  Stars in particular emit vast amounts of electromagnetic waves through the entire spectrum.  Uzan shows us a picture of the Sun viewed at different frequencies to illustrate how we might perceive our sun if our eyes were attuned to, say, the ultraviolet portion of the spectrum.

The sun as seen from across the electromagnetic spectrum.

So, if our perceptions of the cosmos are artificially filtered, if the public image of space is constructed of computer coloured and edited photographs, then why not try and understand it through another of our senses?  What is unscientific about translating the grandeur of the universe into sound and music?

Uzan begins by giving us a quick outline of the relationship between musical theory, mathematics and astronomy.  He tells us the story how Pythagoras came to understand the principles of musical theory and developed the idea of integers in musical notation.  Now, a lot of this went over my head, especially as I am rubbish at both musical theory and mathematics.  But this was an  important foundation for understanding where this lecture was going, Uzan used Pythagoras as a launch pad to explain the history of harmonics, and how scientists have historically attempted to translate the movements of the solar system to musical notation. 

We touched upon Johannes Kepler and his quest to discover organising principles of harmony in the movement of planets within the solar system.  Throughout his career, Kepler fruitlessly tried to correlate the movements of the planets with the concept of nested solids.  Eventually he produced a series of notated “planetary songs”, of which Uzan played some portions of for us.  This is perhaps the first historical example of a scientist accurately translating real cosmological observations of the universe into music, and completed the Keplerian Laws of Planetary Motion, which formed a solid foundation for future scientists, notably Isaac Newton, to work upon.

Kepler's Planetary Songs

Uzan next moves onto describing the concept of natural musical instruments.  The example we’re most directly familiar with is the sound of thunder caused by lightning, but here we some examples that we might not have considered before.  I hadn’t realised, for example, that aurora borealis causes mysterious sounds that scientists are yet to fully explain.  There are many folk tales that describe distant noises, thumps and crackles that accompany the northern lights.  As aurora borealis is the solar wind impacting upon the earth’s atmosphere, and, as a result (and if you’re feeling poetic), these sounds could quite appropriately be described as the sun ‘singing’ to the earth.  More prosaically we also hear sounds recorded from with sand dunes, complete with someone ‘playing’ the dune like a musical instrument.  These sound weirdly organic, footsteps on a beach sound remarkably like a dog barking, and a person sensually rubbing their hands into the sand elicits bizarrely sexy moans and sighs from the dune.

This process of transmuting something into sound is further explored in the next section of the talk, when Uzan looks closely at artists that have attempted to answer questions like “Can we see sounds?” and “Can we listen to colours?”  Uzan shows us the work of Charles Blanc-Gatti, whose paintings of music supposedly influenced Walt Disney in the production of ‘Fantasia’ and Paul Klee, who aims to translate the musical theory into a single image. We see musical instruments constructed that create paintings as they’re played.  All of this proves Dr Uzan’s simple point, the process of translation between mediums, from sound to light, or light to sound allows us to view the world around us from a fresh perspective, with all the attendant benefits.

L'Orchestra - Charles Blanc-Gatti

This process is fun and interesting, but does it have any practical benefit in increasing our knowledge of the universe?  We’re played a recording of the Vela Pulsar, which rotates about 11 times a seconds.  We can appreciate the frequency to some degree just by viewing a waveform of the signal emitted by the star, but it’s only when we actually hear it that we can get a real handle on how it behaves.   It sounds frantic, but is also disarmingly regular.  The recording played reminded me of morse code – an SOS message from the debris of a massive star that exploded 10,000 years ago.  We’re also given a brief overview of the science of asteroseismology, which Uzan describes as hearing stars “beating like drums”.  These sounds allow us to study the internal structure of the stars.  We heard the distant thrum of Xi Hydrae and HR3831.

These recordings from across the universe are the basis for a number of interesting compositions by various musicians.   The example played for us was 'Stellar Music No. 1' by Jeno Keiler and Zoltan Kollath (as heard in the video below).  

Signals from across the cosmos like these have provided inspiration for various musicians throughout the 20^th century.  Some of these pieces, like Philip Glass' 'Orion' are maybe a touch subjective using astronomical data as more of an inspiration, an artistic component of a wider statement rather than something intrinsic to the structure.  On the other hand, there are composers who attempt to directly translate data into music, like John Cage's 'Atlas Eclipticalis'.  This uses as a score an atlas of the stars, with musical notes superimposed over the stellar bodies.  The brightness of the stars is directly translated into the size of the notes in the composition.  As such, it's theoretically possible to imagine this piece as containing the same information as the visual star chart itself.  

If we can listen to star charts, what else can we listen to?  Uzan mentions people creating music from theoretical physics, translating the Higgs Boson in music.  He points out that current theory says that subatomic particle vibrates, and these vibrations can be directly translated to music.  Every visualisation of these particles other than as mathematical formula is an artistic interpretation.  Why instead of confusing diagrams of something that can't really be drawn can't we hear them instead?  

Lady Gaga is probably working on it right now.

At the beginning of this lecture I had thought we lived in a vast, silent and lifeless universe.  What Uzan has demonstrated is that the universe sings to us with an infinite choir.  Our limited human perceptions may not be able to perceive all of these voices, but the cosmos is filled with music, from the pounding pulse of a star's heartbeat to the tiniest trill of the subatomic particle.  So if we're the audience of so much celestial music, what are we giving back?  Well, our radio waves are propagating out into to space, but perhaps more immediately concrete is the Voyager gold record "Sounds of Earth".  This contains a playlist of music that scientists thought put humanity's best foot forward to any extraterrestrial species that might come across it.  You can listen to the full playlist here, and it's comforting that somewhere out, far out in the emptiness of the interstellar void travels Voyager 1 & 2, charting a lonely course away from home.  Affixed to the side is a record containing this:

Those aliens are gonna think we're so cool.

I'm really enjoying this lecture series, and I can't wait for the next one on 'Light', which will take place in January.  My only complaint is that they're not coming fast enough!  It's been 5 months since 'Taste' and after this I'm itching for more!

(If I've ballsed up any of the science here let me know in the comments or email me and I'll correct it.)

Thursday, May 24, 2012

The Sensual Universe – Taste - “Beer in Space” - Dr Subhanjoy Mohanty - 23rd May 2012

Thursday, May 24, 2012 - by londoncitynights · - 0 Comments

The light of our star, Sol, beat down hard on London yesterday.  Perfect park weather.  As I cycled through Hyde Park I considered whether spending an hour in a lecture theatre learning about whether it was possible to make beer in space was a good way to spend an evening like this.  I think other people had had the same thought.  As I headed into the Clore Lecture Theatre at ICL I overheard one of the organisers saying “well, at least one person turned up”.  I was suddenly struck with a slight paranoia.  What if I was the only person who’d decided to ditch the joy of the sun and the happiness of the park to spend my time looking at slides in a darkened room?  Also, being the only person there I might be lectured to directly one-on-one about astrochemistry, which is a bit scary.

But I was determined to go.  The previous lecture in the series, “Sex in Space” by Dr Saralyn Mark was fascinating.  The concept of the lecture series is to examine “astrophysics for the five senses”, namely touch, taste, sight, hearing and smell.  The two lectures so far have pretty pop sci sounding titles, but theseare more of a framework on which to hang up-to-date space science from top astrophysicists (and astrochemists and astrobiologists).  Additionally, at the first lecture in the series, there was a wine and nibbles party afterwards with absolutely colossalglasses of wine and big bowls pretzels.  Clearly, astrophysicists know how to party.

Fortunately, the lecture hall did eventually fill up a bit more, and after a decent amount of people had filed in, the lecture began.  While the topic ostensibly was whether it would be possible to make beer from interstellar chemicals, it was actually the principles of star formation.  My understanding of this was extremely vague, I think almost entirely based on watching Carl Sagan’s Cosmos, which, while amazing, is about 20-30 years out of date.  I love getting a bit out of my depth in lectures like this, and Dr Mohanty didn’t shy away from using slides with structural formalae and displayed formulae, as well as using fairly complex specialist language. 

It’s very easy if you’re doing an open lecture to dumb things down too far, and it’s very frustrating if lecturers assume that any members of the public attending are complete morons.   I always figure that if someone attends a lecture about space, then chances are they’ll at least have a basic ‘popular science’ knowledge of the subject.  Fortunately, in this lecture, a nice balance was struck, everything was explained clearly and precisely without lapsing into overly obscure terminology.  I feel pretty confident that I understood the majority of what was said, and if I had to explain the basics of star formation to someone I’d be able to give it a good shot.

Two highlights of the lecture were the slides on the ‘Hubble Deep Field’ and the Kepler Orrery.  I’ve seen the Hubble Deep Field before, but I always underestimate just how spectacular it is when explained properly.  If you’re not actively learning about space, it’s very easy to forget just how mind bogglingly big it is.  The Deep Field image shows a tiny portion of the night sky, and peers deep into space and time.  We can see thousands of blobs of light.  Each one of these blobs is a galaxy, and each galaxy contains billions of stars.  I love a good explanation of the ‘Deep Field’ image as when done well it simultaneously makes you feel very insignificant, and also full of wonder.  It’s impossible not to be instantly curious about what is going on out there. 

(click for enormous)

The Kepler Orrery I hadn’t seen before, at least not in this form.  It shows various planetary systems without the stars.  It’s impressive enough as a still image, but here it was shown animated.  Just as a visual it’s brilliant, hundreds of planets, some big, some small, some slow, some fast all revolving around their stars.  It makes you consider the universe as a giant piece of clockwork, ticking away.  I like that it helps get away from a ‘Solar System-centric’ view of planetary systems, for example showing us that it’s relatively common to have gas giants in near orbit of their stars.

I only have two extremely minor criticisms of the night.  The first was the lighting.  The slides, were, unsurprisingly, mainly of space.  Space is dark, and the slides looked much better under low light.  I think the lecture was being filmed, and unfortunately the cameraman kept wanting the light to be turned up, which made the slides a bit harder to see.  I figure that the people who actually made the effort to show up should be catered for, not those watching it later.  The only other extremely minor annoyance was that throughout the presentation the font used on the slides was Comic Sans.  This is obviously a personal annoyance, but it somewhat undermines the majesty of space when such an ugly, annoying and ubiquitous font is used.   I, mean, I don’t want that much even Arial or Times New Roman would be fine,  I’d be happy with that.  Just… no Comic Sans.. please.

These are extremely minor annoyances though and I thoroughly enjoyed the lecture.  One of my favourite things about astrophysics is that enormous scales involved.  For example, when astrophysicists talk about things being ‘close’, the actual distance is inconceivable.  So when I asked “You say these clouds of dust are ‘thick’, what do you mean by ‘thick’?” and Dr Mohanty answered “Well by that I mean not thick at all”.  That is, as far as I’m concerned, the perfect astrophysicist answer. 

I’ve really enjoyed this lecture series, and I was looking forward to hearing about the next one in the series which I had assumed would be in June.  Disappointingly it’s now been bumped until autumn.  I hope this doesn’t kill off the momentum, it’s nice to have one of these a month to look forward to. 

Oh yeah, and it turns out you can make beer in space, although it probably won’t smell so great.