>> visit her over there and buy her book and get her to sign it. thank you for joining us again. [inaudible conversations] roberto trotta explains the universe in the latest findings in cosmology using on the 1,000 most commonly used words in english. he spoke to commonwealth club of california in san francisco for about an hour. >> i now use my pleasure to introduce a distinguished speaker, doctors roberto trotta.

professor trotta is a theoretical cosmologist in the astro physics group of imperial college, london. one of the world's leading figures in astro statistics, a new discipline focusing on the use of statistical methods to solve problems in cosmology and as as astro physics. roberto has held research positions at the universe oft general have no extra, universities of oxford, and visiting positions at the african institute for mathematical sciences in capetown. and university of california at santa barbara. also published more than 50 scientific papers, contributed to two books, and received

numerous awards for his research, including case western reserve university, the word order of the british association for the advancement of science, and a public engagement fellowship by the science and technology facilities council uk. please join me welcoming dr. row bert to trotta. [applause] >> good evening, and thank you for being here. i'm very pleased to be here tonight at such an amazing place. i love this city. that sits on the edge of a big body of water, looking towards where the sun goes down. i love it ups and downs, ever surprising corners, it's stories and, of course, it's people.

so, really is the perfect place for me to begin the first of several talks about my new book. the book came out of a little idea. that it should be possible to talk about very hard things in a straightforward way that all people can understand. the problem is people like me, you see, is that sometime wes get carried away and speak about the work in tongue and word that order people cannot understand. it's not possible to have a conversation with other people, people like you. that's the reason why your eyes will begin to stare into space, and probably walk away as soon as you again, happy to escape. talk with only the most used 1000 words. when i heard about this i thought excite be a fun idea to use it to explain the entire all there is.

here's what my book is about and what this evening is about. i'd like to share if you you the ideas behind the book and the story how this crazy idea became reality. so, forgiven for thinking this little piece at the beginning, sounds strange and perhaps was -- spontaneous and as you know, britain and the united states are two nations divided by a common language. that's why i did something a little strange, the reason is that all written using only the most used thousand words in the language. the idea behind the very become published today and i'm honored to be presenting to you today in this very special place. so, by way of background, as we heard a minute ago, i'm a theoretical astrophysicist, and my research in astro physics and cosmology is about dark energy,

dark matter, unknown dark things out there in the universe. and i'm also passionate communicateyear of science. i believe that one of the main roles of scientists in this day and age is to be able to communicate with the public and not just communicate in a top-down way but even engaging at the public in a dialogue about the concept of big ideas, very fundamental questions about the arrest of the universe that we share and are interested in. in particular, astrophysicists modifies are in the position where science naturally draws people, and rather than going and give talk is find people being fascinated by the questions we ask, by the answers we sometimes get, and by the even bigger questions that are still unsolved and the big mysteries in the universe.

so it's our duty to share in a dialogual way, and the reason we're paying taxpayer money into this kind of research, which is as fundamental as few other things in my view in our endeavor to understand our place in the universe. but trying to do that, we face -- as scientist wes face some big hurdles. one, and perhaps the most obvious one, is the problem of jargon. we scientists ten to speak in jargon because those are the words we have -- the words of our trade, the words we have chosen to explain our subject to our peers. then obviously important questions and important ideas can get and do get lost in translation. let me fifth you an example -- give you an example. here is a paper from 1965, by

two gentlemen, who in 1965, working at bell labs in new jersey, picked up using a big antenna a strange signal they could not explain away in any way. they were picking up noise in this microwave horn that they couldn't explain and didn't expect. and so after trying as hard as they could to get rid of the noise, they reluctantly came to realize that it was something actually that was quite important, and they had no clue what this was about. so a team of other scientists that at the time was working on building such an antenna, actually picked up this noise, told them what they were actually picking up. and so they went on and published a paper in the astro physical journal. a paper biteled measure of opt temperature 48 mega cycles per second.

and this short paper, only one and a half pages long, was nobel prize worthy a few years later, but really meant by this title was, we have discovered proof of the big bang. the universe at the beginning was a hot, dense state, and the leftover was the noise we're picking on the microwave antenna. they didn't know it at the time, and this is the type of -- in 1965, surely the idea and the communication to to public must have improved in this past few decades. well, fast forward to 1999. another paper, and you can see science has become harder. two guys, and about 25 guys, and science is harder bus it's

harder to make new discovers now that all the low-hanging fruit has been picked. so, this paper says, measurement from 42 supernova -- every time you see scientific papers with greek letters that's a sign people are trying to be smart, trying to impress they're audience by using letters that normal mortals do not understand. and the paper goes on saying, report measurements of the mass density and cause of -- of the universe based on the 42 type and super nova project, blah blah blah. i'll spare you the rest. what they're trying to say is they found proof that 70% of the universe is being ripped apart by an unknown force field. okay? and this paper, a couple of years ago, and again, very hard for anybody but the insiders to

understand what the paper is actually about. in 1999, you think surely, 21st century things have improved. look at this paper here by cms, compact neuron soleniod. and you don't see authors because it's composed of 50,000 scientists. observation of 125ged with the lxc, now over to make it more attractive. our presenter. [inaudible]

et cetera, et cetera. they're trying to say, we found a dark particle. so, you see why jargon is a problem in my field. and, okay, fair enough. serious papers that are written for the experts and for fellow physicists. so you might not expect them to be accessible to everybody. and so jargon is a problem in our field. not a problem -- a lot more subtle, which i -- until recently, which is the use of language, the fundmental nature of the document. when i say electron or galaxy or star, these are words that are fairly common some pretty much everybody has heard about, perhaps in school or reading a book. what i mean by electron is a little from what people who

don't have my day job think about an electron or galaxy. so using words understand at some level by everybody but actually have meaning that can and does escape. and so in my quest to find new, axisable ways of talking about the science, which i'm very passionate about, i was looking for new ways of breaking the communication barrier, actually bridging the technical knowledge gap and leveling the playing field so we can have an inflammed conversation about my science, what is dark matter, what is dark energy, how does it accident why are we here? and so, i tried a few things. i tried using cookery and food to explain the expansion of the universe. i tried the great cousin cookery

show in the tent, trying to use pancakes to explain the universe. i've worked with artists and designers to create objects, artwork, that tried to encapsulate in a more tangible way cosmology, work with architects, building a pinball machine that represented -- well-won't tell you what i represented. the point is that in those efforts i was trying to find new ways of communicating -- talking about my science in a way that would not only reach people's minds and speak to people's hearts to bring back passion in science. science is a human endeavor, and involves passion, creativity, sometimes frustration and sometimes just plain hard work. how do we bring that back into play? so, for a decade now i have been looking for a new way of doing

just that, and perhaps -- because i love language, doing it with language is something i would love to do. something akin to what -- understanding ways is reported to have done when he took this bag into a restaurant, somebody charged him to write a story or november -- novel to -- with six words. he came up with this, for sale: baby shoes, never worn. pretty intense, pretty powerful. and six words, and an entire story, and a tragic one is condensed in this short story, which is now called flash fiction. and so how can we do that with science? with cosmology in in this farawy concept that is difficult to

bring down to he human space. then one day something interesting happened. i was looking for something entirely unrelated and i stumbled upon on the internet something called the apgor5 challenge. it's an area by a guy called monroe, creator of a web site, xkcd is a series, activity, going on for many, many years, and its, which is that it's very geeky in a good way, but geeky. so geeky that most of the time i don't get the jokes. and those jokes are usually about physics or computer science, a lot of computer science i don't understand, math, and so on, but huge following, and in fact, for an interesting piece of fate, if you like, was in this very

place -- not necessity his room but two weeks ago presenting his new book which came out just two weeks before mine. so amazing how sometimes people pass, intersect. probably not reelected but intersection in interesting ways. but the point is that the -- the cartoon here is a -- it's a sketchy drawing of something that you might recognize as the saturn 5 moon rocket. but the interesting idea was that all the parts of the rocket were labeled using only the most used 1000 words in the english language. of course, couldn't call it saturn, couldn't call it rocket. have to call it up go earth or something that goes up. 5, luckily is a word. so that's good. and all of this is labeled with -- in funny ways, and there's bits and pieces that

say, called room for lots of briefing. so, it was a fun idea, and sure enough, somebody on the internet picked it up and challenged people to write their job in -- using the very same vocabulary, very spare lexicon. so i came upon this challenge and i spent a half hour trying to describe my job using the standard words and this is what i came up with. very hard, actually. just a couple paragraphs, took me over half hour to do it because i kept banging my head. this is what i came up with: i study tiny bits of matter that are all around us but that we cannot see, which we call dark matter. we know dark matter is there because it changes the way other being far away things move such as stars and star crowds. we want to understand what dark

matter is made of because it could tell us about where everything around us came from and what will happen next. to study dark matter, people like me use big things that take lots ofman for people to build. some of those things fly way above us, some are inside the ground. some are lab that make pieces of matter kiss each other as they fly around very, very fast. almost as fast as light. we hope that we can hear the whisper of dark matter if we listen very carefully. we take all the whispers whispet them together in our commuters and lots of tiny whispers we need look at. i go to places all over the world to talk to other people like me, together we can thick better and work faster. together perhaps we can find new, better ways to listen to dark matter. most of them governor -- them

are good people. we go out and have drinks and talk some more. so i published on my web site and forgot about it. then in february last year, i was invited to give a talk, and the person introduced me gave my bio, and then they said something along the lines, and he even writes about science using thousand words only on his web site. okay. and i gave my talk, and then somebody in the public said, what is this that thousand words about can you explain? what i had my computer with me i just read aloud the very same two paragraph is just read to you, and unexpectedly i got the very same reaction. people chuckling and being amused and a round of applause much better than doing my talk, actually, and so that got me

thinking. these notions that actually -- this format could do something to solve the problem that i was trying to get around, to communicate, and talk about science in a fresh knew way to give new eyes to cosmology and hopefully freshen it up and make it surprising and perhaps fill it with hopefully child-like wonder. so i started actually writing what became "them of the sky" as a little project of my own. i just wanted to figure out how far you could stretch this format that i had only used for three paragraphs and could it be used, really work, a short book to be surety still -- to but sure but still a book. i sat down and started the exercise. but first time it was, how die get around talking about this complicated and faraway concept

with a thousand words. the most used thousand words. so, words i really wanted to have and didn't have. i didn't have telescope. i didn't have universe. i didn't have energy, cosmos, big bang, gravity, earth, scientists, galaxies. didn't even have fog which is a very important word. i thing why -- turns out the very universe can be describe as a kind of fog but i couldn't use the fog word. so i was stuck. and so at the beginning was very hard, very hard. i didn't have all -- any of words and ken banging my head against this wall of self-imposed straitjacket. then something interested happened to me. this voice emerged and grew on me, actually. a new vocabulary emerged naturally by itself. the new voice was very much out

of the interaction of what i wanted to say and what the format wanted to say or what the language wanted to say. so telescope became a big seer. the planet, a crazy star. the universe, all of us. the planet, earth, particle became drops, scientists were student persons. moon, the sun sister, why not. and galaxy star crowd, and i knew something for the big bang. now, my first word for the big bang was, the hot flash. now -- then -- [laughter] >> then my editor said you can't use that, really. i didn't know. i learned something. so became the big flash, actually. fine. fine. that's what you find in the

book. and so out of this new vocabulary, new picture of the universe started to emerge in my mind as well. it's a picture of the -- came in at 707 words, and one short -- those are the words. student people are in the book and that -- there's lots of drops for particles. far is a word that comes up a lot because things are far away all the time. seer, crazy, for crazy star, et cetera. so there is sort of the map of the book, the map of the book. so, now i had a little bit -- what i also needed was time and mental space to put it together, and i was very lucky again for one those of beautiful things that sometimes happen in life. i had a here to month stay at

the university of california santa barbara when i was starting the project so during that time i had three months where all i had to do was do my research and i had space and intellectual freedom to think about things, including this. so every day i would go to my office at the campus and look out the window, and pretty much every day this is what i would say. and possibly, and possibly, this is the title of the book came from "the edge of the sky." the edge of the sky meeting the big body of water, the ocean. so i had the time where every day i would sit down and try to let this new voice come forth, and emerge from the book itself. and so the storyline was actually very natural. the storyline of the book came out of a distillation, condensation of hundreds of

lectures i'd given over the years and didn't have to think much.what i wanted to say because i knew what i wanted to explain. wanted to have this arc starting from antiquity to today and trying to explain what we have understood about the universe and what we don't understand. ...

>> from their experience to my

explain what she would do going out all on herself and poetic like and in reality you would not go out by yourself, you would go with somebody with you, and she would spend the night making observations and try to figure out how the light from them to us has been bent and changed by the dogmatic and she pulled her mind back to where it came from and what the ancient people thought about this. the old people who were great figures of god in the sky and what they thought about them and what was the cosmic make-up back then. the story then onfolds, fast forwarding to the present day -- unfolds -- and the big mysteries

especially. by the way of back of background, i expect people haven't read the book because of the publication date but let's cast our minds on what we learned. the content of the book or not quite so simple words. here is a picture of the night sky. and you can see the full moon, in technical terms it is half a degree in angle size. we know what this looks like. but looks at the square marked there. this is a tiny patch of the sky.

it is about as big as the piece of sky that would fit inside an eagle's eye held at arm's length. and if you zoom in and look at the patch of the sky using one of the most powerful telescope we have today this is what we see. there are 5,500 galaxies in the sky and each contain about a one billion stars. just in that tiny arm's length part. if i zoom in, i can see those are beautiful in their own right. but, the most astonishing point is that 96% of the universe is

missing. so that is big news. all you can see in this picture is nothing. it is abounknown and the rest i dark. that is the big question and we as cosmologist we are trying to solve. all you saw in the previous picture was the galaxies around us and this tiny bit of the pie. and then another red bit here is another numerous component which is gas and coal and stuff you cannot really see but it is made of the same stuff you and i are made of. look at the big part of the pie, then. dark matter, 33% or so. so if you add it up, a big part

of the universe is unknown and that is our quest and what we are trying to solve. and that is why the woman went out to solve the dogmatic part. so that is what she is up to. and that is what our universe looks like. but how does it look like in the edge of the sky? let me talk briefly about what our universe and how this incredible universe looks like if you look at it through the power prism, if you would like. this is a picture of dogmatic that is flying all around us. if you extend your hand in the room right now, in a second there are a hundred thousand g dogmatic properties going through your hand right now. you cannot see them but they are

out there. here is what we have to say about this: it seems crazy that certain people should think there is a lot more stuff that you cannot see than stuff you can see. still they do. in fact, they believe there is about five times more dark matter than normal matter. if you look around you will realize that the wide world is made of many, many stars. there are about four times ten stars in the wide road for each person on our home road. if you use a big sphere you will find there are as many stars in the sky as there is in the world and this is just a tiny bit of everything. and she explains how we know all of that.

we think we know what reality is made of but how we came to believe is exceptional. exceptional claims require exceptional proof and thank toes modern technology we go look at -- thanks -- this and go back in time. the speed of light is finite. very fast. seven and a half times around the world in one second but it is so big that the further away you look, the further back in time you see. in order words, light coming to us from the sun left our star eight minutes ago. eight minutes is the time it takes lights to collect the hundred million miles from the sun. when you see the sun discovered we are not seeing it as it is

now we are seeing a eight minutes before. the pictures of the galaxies are as they were 4-5 billion years sonia -- ago. we will pick up light that came from the universe right across from the big bang, 380,000 years after the big bang, we can pick up light from that many years ago. this is actually an image of the universe. this is an image of the end of the visible universe and i mean this as scientist state. those are not galaxyies. stars and galaxies didn't exist. all there was was matter, light and dark matter.

you can see where they grew out of depicted in red. before this time, the user was filled with high energy fog. and i say high energy fog. but in the book i cannot say energy or fog. there is another way it is talked about in the book. this is as far as back we can see and we can learn an incredible amount of information about the universe. the universe is 13, 798 million years. we don't know the age of the earth to that precision. that is the same as being able to tell the birthday of a stranger just by glancing at them within one day precision which is incredible if you think about how we now understand.

the reason is 95% of it is totally dark. so what about the other bit in the cosmic pie. the bit labelled dark energy. what about dark energy? the way people found out about the dark proof; let's read about that. she steps outside in the cold night holding a cup of hot coffee with both hands. the wide road is beautiful and the dark clear sky and once again she can not help but be amazed by it all. doesn't matter how many times she has seen it but the sight of the stars is enough to make her gasp. it seems still but it is changing all of the time.

it is hard to believe everything past the world and stars are running away from us. yet, like mr. hubbell found long ago, the star crowds are running away from them as the space is getting bigger and bigger. so not only is this an incredible discovery hubbell made which is an amazing fact that if it is growing with time and the star crowds are moving back in time and you reverse the arrow in time. the star clouds were closer and closer and there comes a point at the beginning of the bottom of the diagram where they were circled in a hot, dense point

that we now call the big bang. this is not only what our observations of the night sky tell us and of the aluminous acre of the big bang but what we learn is the universe isn't only becoming time but it is becoming bigger at an accelerating pace and that is because of the dark push. let's go back and see how we can see the dark push out there in the first place. certain people found that the death of stars gave them the right table light. meaning that if you use a night table light, in order words, a very luminous source of light, and you measure how bright it

appears to you and you know how bright it is to begin with, you can work far away things in the universe and how far away they are moving and how fast they are moving and that is the discovery i was talking about before. so not just any star will do. let me get a picture of a dying star. they need a star that dies in a big show and light and can be seen from far away. they looked at a number of star deaths and found some could be used like night tables because with their last night they all gave out with the same breath. perhaps because the stars are made of the same stuff and die when they become heavy and eat up another star. they managed the catch a new number dying stars and worked

out how far away the crowds are thanks to those. they knew how fast the crowd was moving and when they put those two things together they found something no one expected and that is the dark push of course. and then the dark push itself is a mystery that points to the existence of other parts of the universe. a multiverse, which in the book can't be called a multiverse, but it is explained using coins. in this case british pounds, i think. and so the book then and speculation about the universe and if there are other ways beyond the way we know it exist. all of these are questions we are very much still investigating. some of it is controversial.

how can we talk in a manner about things beyond our uniurvee and away from the possibility of observing them. let me leave you with a closing thought. after the night observation is over, it is time for the student woman to go back home and reflect and think and work very hard on everything that big sir has done for her during that night. she sits down, the big blue body of water in front of her seems to be gone without edges and end. she can feel the warm hand on her face. she feels happy. big sir did a good job.

she can go home now but her job has just begun. there is much more to do in the coming weeks to make sense of what we learned. letters, words and entire books are hidden in what has been given her written in a strange tongue. little by little she would understand it better and ask the right questions in the right way and she might learn the truth. she is mine and the sun. i leave you with those thoughts. i would like to thank you again for being here with me tonight sharing this very special day for me. today the group comes out and it is an initiation speaking to you and it has been great sharing thoughts with you. i would be very happy to take questions and sign books at the end. thank you very much. [applause]

>> we would like to remind the audience that this is a program from california and you are listening to all you need to know about the areas -- we open up q&a. we are setting up a microphone because we are video taping. if you have questions, come up to the front and speak into the microphone sinceee are -- since we are -- recording. >> i would like to know how a normal -- or not a normal person, a lay person is supposed to conceptulize the stuff that

banged but is smaller than an electron but started the whole universe. >> thank you for the great question. we are normal people, too, let niasia ellime say. thank you. that is a great question. what you are describing is a great paradox. if dark matter is a new particle beyond what we know about it is quite possibly a subatomic particle that has no special extent. and yet it takes up 23% of the mass energy of the universe. so to explain the galexy and

expans of the universe you need a particle that is pragmatic and a thousand times more than the atoms that make up the ones in our body. the big question in cosmology is that: how do we close the loop and explain the structures we see in the universe with a point-like particle of no special extent. this is why the questions are important for physics. they merge together the rules of gravity to the smallest case that are ruled by other forces and to understand it we need to find a new theory that merges the four forces of the universe.

you are putting your finger on a hot topic and that is a question that remains open. we don't have an answer to that either. >> i'm a writer so i am curious how this project has influenced how you write and communicate your scientific papers. >> thank you. that is an interesting angle from me being a writer. i can liberate it because when you put on the straight jacket it is straining at the same time and forces you to find a new life and creates a new voice that wasn't mind and over time

the straight jacket became like a weather and we needed to look up the words and the voice itself grew on me. but when i shared that voice and go back to the usual writing i am more aware of the words i use and the assumptions i make as i use the words. so in a sense, the full extent of the lesson is great, but i am much more aware and self-footed with my chose of words. i am now much more aware of the fact that there are many layers of association with the words i use and this pushes me to find the even more clear than before. even sharper and crisper in my writing. i am not sure about my writing because it is a special audience and there is not much space for writing creativity maybe in the

science but not in the way of the scientific papers. it is a very different set of skills we use to write the papers. my other writings, made me focus on the hidden layers of assumptions between us and this invisible barriers that sometimes hinder communication and dialogue. >> one of the things that has baffled these physics is gravity and now this is one topic you are addressing but i have heard inferences about gravital weights and would you comment on where we are in solving the problem of gravity, what is it, and how does it work. >> gravity is a mystery. we don't understand how it binds

with the other unknown forces. i think your question touches on two aspects. one part was about gravity waves which was the announcement made in early march that certain people found evidence of ripples in space time in the universe looking at the light i showed you before the maps of the universe. the state of the art of that claim is that it was brought up at the time and it would have been a very big discovery, if confirmed, but at the moment it seems what they saw was not actually, for the greatest part, wasn't ripples from the big bang but largely due to dust in the galaxy. although this isn't settled. it will be settled in the next few weeks as the satellite will

reduce new data which are expected to clarify and that is up in the air and we will learn more about it before the next few weeks. there is a bigger topic of gravity, though. we have learned some very interesting things. this is one of the ideas that i explained in the book about how gravity wasn't seen as a force. but i understand it is actually geom geometry. it is the shape of space time really. when we think of the moon going around the earth, there is gravity keeping it in orbit around the moon, but what the moon is doing is going as straight as it can, only face time itself is bent by objects like the earth and that makes a straight path and looks like a circ circle. so the moon is going straight.

so the geometry of space time has been challenged many times. specially to explain away gravity. we can forget it and wouldn't it be a better universe. but would have not succeeded. the idea of gravity has been tested in many ways and so far it has always hold up. so it is right. but we keep testing this in greater and greater detail and perhaps we will understand the gravity in a different way one day. >> two years ago professor samual ting set-up a satellite and attached it to the international space station. the goal of that was to see if we could possibly figure out --

of course it wasn't him, it was about 200 operational people, and it was amazing he coordinated that being he is in his 80's. it has been collecting data two two years and they are recently analyzing it and finding out what dark matter is. can you elaborate on that? >> yes, i think it was as late as last week that the data came out. i remember on my way here, i had time to read the scientific paper and saw the key plot that shows this detector flying on the international space station and what it did was measure the energy of matter in a particle which was the anti-particle and this is a technical question

that i could answer with a thousand words but that would take hours. so the short answer is it is able to measure and measure to a higher precision and energy before. the idea behind the measurement and why we are interested in back matter -- it sounds cool and it is great in some situations but it is boring from a physic's point of view because we are producing it all of the time. but from outer space it is interesting because not many processes produce black matter. so if we find more anti-matter perhaps it is coming from dark matter with the particles hitting and kissing each other and giving it out and that is an

indirect result of dark matter. but things are complicated because the anti-particles get bounced around by fields and interrupting this is hard. i have not had the chance to comment on the data about they expand to new energy and the conception so far is that the reported success could be explained by normal astrophysics. whenever you have something that can be explained, you don't need to invoke the potential of dark matter and people have been wary. it isn't a smoking gun so i expect there is going to be more work interrupting the data. >> thanks to amazon i was able to download your book this

morning and enjoyed it very much. i used to have a job trying to get funding for exploring this and i always had a hard time getting the scientist to explain in a way congress could understand. admitting that is a low bar. and i thought there should be a discipline for students to read science in simple terms so i appreciate what you are doing. [applause] >> thank you, sir. that means a lot to me. my colleagues have been supportive of my project. but some have been quite baffled by it. and they speak review and there are five million different words in the english language and why

should we go down in words and make up words. and some people take the view we should not dumb things down. but i don't regard be book as being a dumbed down version. it is as a different look on reality and the universe and it freshens our views. we need to be able to communicate with policy makers and the people that fund our research which are people in government and the street; taxpayers. this is paid with tax dollars. it is only fair and right we communicate with people and explain what we are doing, why we are doing it, and why it is important. and i don't think they are doing their job right.

they might be brilliant scientist but there are other sides and i think that is important nowadays. no one can do discovery on the lab bench now. it is big corporations putting time and money together. my favorite view on this is when from lab was asked my congress in 1962 how this would help the united states at the height of the cold war. and he said mr. congressman, maybe the money will not help the united states but it will make it worthwhile defending, which i think is a great answer. >> well, thank you for the talk

today. your simple language has encouraged me to come up as someone who doesn't know too much science. i saw as a scientist describe dark matter very good. he said there is three types of matter, anti matter, matter, and doesn't matter. except it does matter. but i want to ask you a serious question all kidding aside. i don't know my science, but i am curious if matter is dark, and you cannot see it, and the human experience, how do scientist know that it is really there. you are saying 95% of the universe is unknown. so how do they prove that? what gives you the assurance you can say there is matter there,

it is dark matter, but we don't know anything about it. can you say something about that for the person who hasn't studied physics since high school. >> absolutely. there is two chapters in the book dedicated to it and it is as a great question. there is so many lines of matter and i have to say everything is always provisional in science. we never things with absolute certainty. we know the proof we have and what it looks like and we are on the provision of science and trying to learn more and the future ideas might change. there are new things we can say about the evidence for the matter. i will so you one thing that will be as close as can be to showing you dark matter that can be seen with your naked eye almost. this is a picture taken by the

hobble space telescope. you see the ark-like features. i know the camera crew will hit me for this but like here, there and here? look likes a camera lens flair but it isn't. what you are seeing here is those little bits of art are images of distant galaxies whose light as it is travelling through the universe has been bent by the presence of other matter. the visible part of the matter is the bright galaxy you see in the center. so, now, telling us how much bending matter does to space time and how much bending and art-like sections we should see and those features are called rings for this reason. we observe the rings and we can

work out using general activity how much matter and mass there needs to be in the center of this cluster of gal texas -- galaxies -- to do the bending. and it turns out you need more mass in the cluster of galaxies to explain the bending of light. so that is one of the pieces of evidence we have for dark matter. and there is many more. many, many more. and it looks like something is out there doing all of this pulling; gravitational pulling. >> one last question. thank you for writing the book. i have not read it yet but your approach is great. the only thing i dislike more than having my intelligence insulted is having my ignorance

insulted so it goes toward that. this is a subject that the nature of the actual universe i have been thinking about since i was young. i think the smallest particles that are measurable and i think our universe might be having multi universes. and people say like infinity or eternity is a long time or distant but they don't get the concept. so i am wondering if there is any scientific value that idea. >> that is very much speculation at the moment. anything i am saying right now is speculation and we cannot prove it but yes, you are right. one of the ideas of the

existence of dark energy brings about is our universe could be everything we can see. all there is could be a tiny part of a much grander reality when we call the multi verse. here is a picture of that perhaps. you can see the little yellow, 15 billion light years, is what we can see around us. if our measurements are correct it will expand forever and is n infinate in times. but this is a multi verse that is made of many bauble like things. and each one with different laws of physics in them. and they are brought into explain the mystery of the dark push, as i call it, and we don't

know if any of this makes sense. we don't know if we will be able to prove or disprove our ideas because we cannot step out of the universe and look for others. this is controversial and excited because it goes to the heart of one of the biggest questions every. why are we here and what does reality look like? it is exciting we can start asking this question with this kind of ideas. so absolutely a great question. >> thank you for your comments today. we would like to thank the audience here as well as those listening to the recording. and now this meeting of the common health club of california celebrating its hundred year of discussion is adjourned. booktv is on twitter. follow us to get publishing

news, scheduling updates, and to talk to authors directly during live program. twitter.com/booktv. >> this is on the night of 2009. he is a poplar president still. spoke to congress and there was in the air with tennessee williams -- what -- might have called the powerful odor of mandacity. and among the lines that were prodded out was this: nothing in this plan will cause you to change the doctor you have. nothing in the plan requires you to change what you have. now at the time, obama said this he may have thought this was true. and yet,i went back and checked the record on this and within two days of that announcement,

there were a serious decent in major publication that the whitehouse must have known was possible. the first time he gets a pass. the next 45 times no pass. but that is not what wilson riled up. it could have been one of the things but it wasn't this. when obama announced the claim wouldn't insure illegal immigrants, that is when wilson yeld -- yelled out -- you lie. and all hell broke lose. for the first time in 20 years, nancy pelosi raised her

eyebrows. i didn't think that was possible. joe biden literally starts tsk, tsk. and obama loosing his place on the teleprompter which could be a disaster. and there is a collective gasp from the democrats and it is the kind followed in the school yard by saying i am telling. the republicans rushed into the mike to apologize and the democrats tried to raise money off this which they do much too well. i liked the response of democratic whip james clyburn calling wilson's behavior totally disrespectful and a new low for the state's delegation. he hasn't study south carolina

history closely. in 1856, preston brooks, a congressman from south carolina, upset by the abolishnist talk went over to the senate with his body and clubbed a senator nearly to death, disabling him for years, and his fellow congressman held them off at pistol point. that is a low. you cannot gut lower than that. history is never a strong suit for our progressive friends. anyhow, missed in the hub over the joe wilson's remarks -- he didn't say you are lying or that is a lie. he said you lie. it was like a declaration of the man. five years ahead of the time

before anyone else caught on. and it is like a stare dances people sing, and obama lies >> you can watch this and other programs online. >> here is a look at upcoming book festivals coming up. booktv will attend author night. and the next night we are live with the fashional book awards from new york city. and then we will be live from the miami book fair international. let us know about book fairs and festivals in your area and we will add them to the list. e-mail us.

>> the author of this book set out to do what her father started trying to do. trying to get support for the algeri