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>> Physics and I'm delighted to introduce our speakers today 2 years ago we had a similar event in which we celebrated it and we had speakers tell you no supper the Nobel Prize in that case he was going to wave and the speakers were members of the school physics specifically the Center for a lot of his stick us to physics this year again.

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This caller is for who it's a Nobel Prize winner Warner enabled the signs that were to his speakers are going to talk about the 1st speaker is Professor Joan Weiss he caught his bachelor's degree here in Georgia Tech When was there 80012001 could ask you know how much Georgia think has changed in those years.

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He went to get his p.c. in Stamford and he had positions in Princeton and he actually Wark he was supposed to walk over and over and over laureate it while he was working in Goddard Space Flight Center he specializes in 1st objects in the universe who's a computational astrophysicist he uses the most powerful computers available in United States to investigate objects like the 1st black hole to form in the universe the 1st stars the 1st structure and that Wark is possible because off what Jayne's peoples to it that theoretical discover it's a Physical Cosmology.

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Our 2nd speaker is Professor going to lead she specializes in the planet's dynamics in particular and shields a study dynamics around supermassive black holes she called here by chillers degree in Caltech he she then went to Harvard to get her Ph d. and stayed there as a Harvard fellow and we were very very fortunate to be able to hire her here and war to bring her expertise to Mexico planets and just to end my introduction want to make a prediction that there is going to be a no another Noble Prize in exoplanets and that will be when they discover that it's life in this planet this is for the 1st discovery and sure that he will be so spectacular discovering life in other planets that there will be an old problem let me just introduce ball of you 1st with the professor was will give us the 1st part of the presentation and then for the gone to.

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Thank you Paula. Good evening everyone so it's great to see everyone turned out to hear something about the Nobel Prize in Physics this year so I'll be talking about cosmology and the work that James people laid the foundations during the seventy's the sixty's and seventy's so in the next 30 minutes we'll say you know what is cost of ology and because this is what his works his life's work was all about and to give you a sense of what kind of leaps and bounds he made in the sixty's and seventy's and eighty's and ninety's we want to see if some historical snapshot of what the field was like in the 1960 s. because this is a time when they 1st saw up humans 1st saw the afterglow of the Big Bang before it's all theoretical and I'll go into details about that and at the time as a very small field is very speculative as well and so that just you know is a blank slate on which people could actually their eyes upon and then I'll go over some of one of a few of many of his pioneer ace high nearing studies they did in the impact on current day research in cosmology and galaxies so to give everyone a sense as you know what is cosmetology how small it is a study of the of the universe on the largest scales so to give you a sense of scales of the universe Here are pictures from the earth our solar system the solar neighborhood our own Milky Way And these are zooming out by a factor of around $100000.00 times so then we go to our local galactic group or supercluster all the superclusters in the whole observable universe which is around 40000 light year 40 sorry 40000000000 light years across.

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And so you know these are the largest scales that we're studying and we have to study them over billions of years and just to give you a sense of the timeline that cosmology actually looks at as we study cosmology starting from the big bang and we have to study subatomic physics at these early times because the universe is extremely hot very small and involves nuclear physics and national physics and we study how these how the elements actually form in the 1st few 1000000 minutes and then go on to to cool down and then and we go here this is the cosmic microwave background which I'll detail later and then we'll start to form the 1st stars and the 1st galaxies over 13800000000 years of cosmic history to today right where we are today and we have to understand how all this works and because of people's won the Nobel Prize you know all of that work that is done laid our modern foundations of the field so what do we actually know today right I want to set the stage of what we know today and just compare what he actually did in the past so what's in the universe so most of it we have no idea what it is right with the dark sector the dark energy 73 percent of the mass energy content of the universe of dark matter so I should say that dark energy is actually causing the acceleration of the expansion the universe dark matter it only interacts through through gravity so it's the backbone of the universe because there's so much more dark matter than there is gas and we only see so there's 4 percent of the mass energy in the universe that's contained in what's called baryons and normal matter but of that 4 percent we only see point 5 of that in stars this is some of the information that we have to see from the radiation that's coming from the stars.

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In other word and and other masses and neutrinos like these ghostly particles that are passing through us billions are passing through right now and heavy elements meaning anything heavier than helium so so how do how do you. Actually detect these objects in and what is the future of astronomy and astrophysics number one we have big telescopes and we're going to have even larger telescopes in the in the next decade so in the mid 2020 s we'll be building detect the farthest galaxies across the observable universe so we have will have 30 meter class telescopes you can see the 18 wheeler there you can see just how huge this is a 3 are being built in the world 2 in Chile and one maybe in Hawaii or the Canary Islands and also we have the James Webb space telescope that's going to launch and a year and a half now finally.

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So these are huge telescopes that will provide us detailed information about galaxies and stars and planets across the universe all contextualized by cosmology and also we have the largest supercomputers at our disposal so this is one example of that was that it is now the fastest in the world up in Oakridge It's called The Summit supercomputer has 2400000 course so a lot of has like 4 or 8 course as 10 petabytes of ram is tremendous but we have all these tools right telescopes detectors and computers at our disposal now to actually understand what's going on in cosmology and galaxies and this produce big data right we have to understand how this all this goes but back in the sixty's it was a much simpler time hadn't pen and paper or pencil and paper probably.

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And and how was the time how were how was cosmetology in the 1960 s. So do you back up even more in the late 1920 s. Hubble and the mart they actually discovered that the universe was expanding so what they saw was so here we are in the sun and what they saw as the farther away the galaxy the faster it was moving away so that told them that the universe was expanding so you can imagine the nice analogy is raisin bread if you bake some some raising the bread dough right that used will cause it to expand but that the raisins are bedded in that dough and as you bake it they will expand and become farther and farther apart so you can think about the bread as our universe and the raisins as the galaxies but if you reverse the clock right because the universe is expanding you can ask your the question what happens if you reverse the clock and go backwards in time to the very beginning and that means that the universe has to come to a single point a big bang a hot Big Bang because as it gets smaller and smaller you get hotter and hotter temperatures just as the universe compresses and if there were it was very hot it should be radiating a lot of a lot of energy through its photons through black body radiation and it was theorized in the forty's and fifty's that the should exist and but in the early sixty's and 964 to researchers from Bell Labs they actually discovered this afterglow of the big bang for the 1st time and this is known as the cosmic microwave background because it's the background radiation is coming from everywhere and and it's in that microwave because this hot gas after the Big Bang what happens is as it travels across the observable universe that those are the wavelengths of the light the stretched out is rest shifted and becomes less and less energetic as it travels through space.

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Ok so in 1988 so this discovery of the scene be there's Bob Wilson and the heiress and seeis that discovered the c.n.d. there is that the horn tells our telescope in the background they actually had a lot of problems with this because I mean it was an accident discovery I mean all discoveries I mean the best discoveries come by accident I mean they're trying to discover to look for radiation from the galaxy or or mainly from the galaxy and they're looking for a background right but but they kept on getting something that was 10100 times larger than they expected and they went through they checked their electronics their detectors they even found some some birds nesting in the in in the telescope so you can see it's a nice nest there even went in there and start cleaning out all the bird shit and just going through all the errors in there and this is a picture of what they saw you can see the Milky Way actually glows in the middle in the microwave but surrounding it coming from everywhere in the universe is this background of microwave radiation and a perfect black body of 2.7 Kelvin and if you reverse that in time actually predicts that this is coming from a hot Big Bang years or minutes or seconds after the universe was created.

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So 2 leading forces it wasn't only Jim peoples and he graciously acknowledged this in his noble speech it was also. So he was a Russian astrophysicist and I forgot the university but and Jim peoples was at Princeton actually all of his career he was a grad student is actually an undergraduate and the University of Manitoba and then he was a Princeton for his graduate studies guy's p.c. in 1962 and then he was hired right away as a professor that doesn't happen anymore and physics and he's been there ever since and he's 84 years old but but once this c. and b. was observed any discovery brings a paradigm shift to science and there's basically a blank slate for Therese to actually to throw ideas out there and to see what actually makes sense or not so both of these these these pillars in the field in the sixty's and seventy's they basically built Physical Cosmology from the ground up and this is an interesting prize because usually Nobel prizes are awarded for a single discovery right this coverage of the c. and b. But I mean Jim peoples over and over like his whole career he he has you know has so many papers I'll go over this later and he's made multiple discoveries so everything that these people have done you know I.

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So it laid the foundation so that you know me and other people today can actually do our research and you know I met him a few times when I was at Princeton I mean he's sometimes you around people with egos but he was just the nicest guy ever I mean he was humble and he was friendly and as talkative he is he's approachable but he was great to talk to is very bright.

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And he still comes in every every once in all 10 years ago he came in almost every day 7 days. So I did a word cloud for his $248.00 lead author papers that's amazing I mean you can think about that he is publishing for 40 years so what is up 6 papers a year but if you look at what he's study cosmological models' cosmology a sprite present day galaxies formation principle and so on but by his main focus was cosmology and what that actually meant for the formation of stars and planets and galaxies and also I want to look at you know what his impact was on the field so if you actually plot if you look at how many researches have read his papers so this is how many people have read the papers as a function of the publication date you can see even his papers back in the sixty's and seventy's they're still being read and write that's.

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The key of relevant research right you can publish a paper it may be relevant for a few years and something better is discovered and just disappears people kind of forget about it but his work is just tremendous over decades of work so I want to go over you know highlight a few of his discoveries in sixty's and seventy's number one is that if you think about the universe expanding it's going to be very hot it's going to be most like the interior of a star in which you will have nuclear synthesis we have protons that combine with with Newt neutrons to form to turn and then it goes on to form helium so he started thinking about this idea of when you get the expansion you'll get just the right conditions to actually fuse together protons and neutrons to form helium and he was one of the 1st to actually apply these ideas these stellar ideas to the Big Bang so this is 2 years afterwards and now I want to say that he was actually working.

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Still on the c. and b. before I was discovered So I mean the hot Big Bang ideas were from the forty's and fifty's and he was actually working on theorical models when he was a student and after he graduated. On these ideas so this is one thing that he discovered another I don't think the biggest one is how galaxies form after the Big Bang because as predicted he actually is one of the ones that predicted that you would get small fluctuations and density that were observable in the c. and b. and he calculated how the small bird would actually grow because of gravity into the larger and larger objects actually that you would have galaxies forming from the small part of Asia and I'm talking like one part in a 1000000 that would grow into the into you know galaxy that we see today stars and planets and us in the end and also he explained how galaxies actually get their spin because you can imagine that you have an expanding universe and in some gas cloud is expanding with the universe but some point it's going to collapse under some gravity but when it's at the biggest anything surrounding it is going to its gravitational force it's going to torque it right at this larger base it's larger size and it's going to torque it get some angle or mentum right spin and then all collapse under some gravity and as it collapses it spins up just like a figure skater on ice Another thing is that he started looking at you know what were the 1st stars in the whole universe so in this expanding universe the gas would actually start to cool down and these perturbations these small fluctuations in density they would actually start to collapse and when they would collapse and what the masses would actually be.

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But he predicted that these globular clusters there's there's dozens of these around the Milky Way and around all of all any galaxy that you see so this is around 10 light years across but there is like a 1000000 stars in there some the dead to stellar clusters in the whole universe but he was wrong on this right and many ideas you're going to be wrong on some of them but on most of them he was right so you know the best one so and also he discovered in predicted how large scale structure actually forms in the universe and and and him instead of it they actually predicted that you would get some sort of cosmic web in the seventy's right through the theoretical work and later that in that decade there this big galaxy survey from the harbor to see if a that that looked at tens of thousands of galaxies and start seeing their errors is some structure here you can see some condensations of each point is a galaxy you have some you have some regions that have voids that have very few galaxies but you have over densities of galaxies here looks like the elements and nodes in the structures of galaxies and and that was just a confirmation of what they did earlier so it was nice to see that you know 5 years passed and their theories were actually confirmed and I want to spend some time on how the structure actually forms it's a nice thought process to say you know how do you get this web this cosmic web so this is a little thought experiment this is actually called the dovish approximation by the other guy so this is actually taught this in my graduate level class right though I'm not going over the math but just pictures so here is early time this is only in one d. density and we can ignore this is velocity.

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But over time it starts to collapse under its own gravity and in the case they are looking at is dark matter so I did mention that dark matter is collision with meaning that you have to cause dark matter to pass right through each other unlike gas normal gas which will collide with each other in shock heat so this is why you get it to get to the peaks here and continue to oscillate and start to collapse but if you extend this idea this one d. idea to Tootie you can think about a sheet right if he thinks about that one d. case you get your thing and one dimensional space in a 3 d. universe if things collapse in one dimension you get a sheet that sheet collapses again it's going to fold on top of each other this is what's showing here and if you project that and other dimension you get a filament here and you can get these 2 filaments that intersect with each other and you start getting these nodes what's called dark matter halos that are the high density regions in the universe and you can think about that as 3 sheets intersecting with each other where those sheets intersect is where the filaments are and where the filaments intersect or where galaxies form so they they theorize all this in the seventy's with pencil and paper it's amazing what they can do what I can't do that I need computers to actually do my work I do some pencil paper but if you compare this with modern day simulations you do see the structure this is a this is a dark matter simulation the cosmological simulation that you are seeing a field of view 200000000 light years across and can see that you get filaments you get these these nodes these dark matter halos in which galaxies would Foreman.

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So so this is that's just some highlights of the decades of work that he's done in Physical Cosmology and as I said before what he's done allowed future researchers actually proceed with future discoveries more detail but they laid a foundation answered a lot of the big questions laying out there for us to fill in those details so just to give you what went on after the c.n.d. was 1st discovered so that's shown up here in the mid sixty's but and in 1902 there is a satellite called Koby actually was a 1st one that saw that these fluctuations in the cosmic microwave background so you can still see the Milky Way but you start to see that with better sensitivity better angular resolution you start to pick up these small part of ations I should say that these part of ations that you're seeing is one part in 300000 so this one the Nobel Prize again in 2000 and.

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6 and and and that was John Mather was one of the prize winners and also in 2003 there's another satellite that was launched the Wilkinson Microwave and and I said the probe so Wilkinson actually worked in with Jim peoples he was a student at the same time in the same ph d. group are same research group in Princeton at the time and went on to work on on detectors and satellites to detect this microwave background but you can see how much more structure they saw in 2003 and now today there is a plank satellite sees all of the structure so now the Milky Way has been subtracted from here and what you're seeing is a babe or baby picture of the universe 380000 years after the Big Bang and these fluctuations are tiny and then over billions of years they grow into larger and larger over densities in which galaxies form so this is the seeds of our of galaxies that we see.

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So we can fast forward in time right here's a c.m.d. here that's those small fluctuations then now today we study how that progresses from that very early time all the way to the present day and understand how the 1st stars formed how the 1st galaxies formed and how all subsequent galaxies form until the present day that form our Milky Way to form the satellite galaxy that we see around us and so that's proceeding over cosmic time and how these galaxies they're forming you know they may be observed billions of light years away but we can use telescopes as a time machine because it takes some time for that light to travel to us but what I want to show you now is what computer simulation because that's my expertise is computer simulations what's been allowed that frame the theoretical framework that Jim peoples and so dull bitch and others did and decades ago Laois to actually study what we do today so I don't actually use this computer but they they look very similar supercomputers filling the room hundreds of thousands of course but here is one.

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Often hears Once I mean lation. That we did on the 1st galaxy says this is the largest and most outstanding missions. He said. Early on that you started this. Man's history and. You're. Just want. To join Star. Was the. First man to get. Over. Your super. Stars every post.

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Gas trace the. System. Is a. Gas. For starters. Is that. Yes. Yes. Or. Very. Strange. Tells us genes with these things is to. Test our steel. Ok so that's only 400000000 light years after the Big Bang or point 4000000 years after the Big Bang for 40400000000 years after the Big Bang showing the 1st galaxies but then time goes on and you start to form more and more massive galaxies so this is a simulation based out of mit Georgia Tech of the north and and he can see all these these filaments forming you get this dense gas is colored by its temperature and this also has many different physical physics in it as well stars black holes magnetic fields as well and can see how things are things are slowly turning away they're growing at time in a rotating the the universe as it rotates it where the camera is rotating or around in the some relation and it's growing with time this is around 5000000000 years after the Big Bang galaxies are contained in these and these and these halos here and we're just looking at galaxies like the Milky Way growing over time so we can actually focus on one of these galaxies forming.

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And what showing here is the gas that's falling in it's spinning already and this is a like a large scale view and the lower left hand corner these are the stars forming and this is the gas now they're going to stop it rotate it you can actually see that the disk like structure in here is is is gas density Yes gas down c.n.n. and neutral density and they go forward in time and you can see these mergers of smaller galaxies merging with larger galaxies and this cell galaxies grow This is what Jim peoples and earlier researchers in vision and when they're doing this on with pen and paper with analytics and is probably in their mind they could actually see this but with the powers of computers we can actually simulate this and look in this in a much greater detail to actually understand our origins from the Big Bang all the way to the present day how stars in the earth form and many thousands or millions and billions of planets which we'll hear next from gong really thank you thank you and we'll take questions after Professor Leith speaks.

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Ok Thank you John for the discussion about cosmology and now let's shift gears and look at places that are closer to us and. As we know the 2nd the other half of the know about price was awarded my year and kwaito for their discovery of exoplanet around some like star.

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Sun our system so why is this interesting so it's natural to believe that planets would exist outside of our solar system and indeed for a century this people have speculated this idea and a question about the uniqueness of us in the universe. As recorded in the literature even back in the 1500s through the list stated that there may be infinite warts like ours existing in the vast space of the universe and also similarly in the 1600 Newtons a wondered why there would be our planet to assume planetary systems similar to our own sort of system existing all but hang around other stars in the universe however Back then there was no way of knowing whether this is true whether planets could choose only exist around other stars and if they did exist how common are they and the weather this similar to our own solar system lots of efforts have been made to test this so the search for exoplanets planets all side of our own solar system.

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As being $855.00 a tick of study the motion of binary star and found some unexpected features which could be the existence of planets around the stars which gravitational pull of the stars all that whole motion as they can see planets are quite small and being so it's very difficult at the top of the planets directly so people have to rely on the incorrect signature of the planets on their host star in order to find their existence and similarly later around 968 to 76 van de Camp study the star caught of men though they're not star and know to some brightness variations and he argued that this bright in this variations could be at the 0 to the existence of giant stars guessed Giants existing around a star however it was later found out that these signatures were actually not due to planets so people still don't know where their planets are they are in the universe.

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Then in the late tonight 8 Heyse exoplanets were actually discovered but nobody know they were truly planets specifically by Ken Bell and his coffers they study the motion of the star go to the our companions and also by lift them and his collaborators they also study the motion of stars spy their companions and both teams find come stellar companions that have lower mass subst the objects that have mass that supposedly should lie in the wrench of being a planet.

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All over to stop jacks are very massive they can times the mass of Jupiter the most massive object the most massive planet in our own solar system and they are very close to their host star corresponding to a period less than 10 days so nobody expected such giant planets could exist so close to the host star you could only thing this author's so they can see in their papers they hinted at the possibility that objects could be a plan days but they are still not sure about it so they mention that this low mess objects could reproduce and the tip of planetary mass spec chum and also in this paper he mention that this company and is probably a brown dog all may even be a giant planet so unfortunately back then it's still not clear where the planets could indeed exist outside of the solar system.

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And I have met them a few times and actually his office is only one floor away from mine and he once told us that after the discovery of this exciting system actually people are not very excited about it because if this object were a brown doff this is just a very typical shot of period stellar binary so I fortunately this system did in the kick off the start of planetary discovery and characterization then in the year of 1902 finally if you will become aware that planets could truly exist without a soul or all side of the solar system thanks to the remarkable discovery by Watson on a frail where they found 2 planets around the posts.

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Over this planet citing a very different environment become apparent with the plan days of all own solar system because they all bit around the posts are instead of some like Star So what is the pasar a Pasar is the object a has more mass than the sun but its size is very small its size is only around a large city and to make it a worse it has very strong radiation and a stream really magnetised So if the planet could host life the civilization would be very different from us and perhaps much more advanced comparing to us because this planetary system is very different from our own summer system this is likely the reason that Dr frail and the Watson missed the Nobel Price of Fortunately then he becomes the year of 1905 when Dr Meyer an acquittal finally discovered the actual plan that $51.00 Pegasi be around the sun like star So this is trying to mark.

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So for the 1st time we know for sure that planets do exist around the sun like star all side of our own solar system although it sounds natural that while I would expect planet to exist on the other stars in the universe this is actually an unexpected discovery and this survey Dr my year and Crystal were conducting was truly adventurous and the courageous This is because as we see in our own solar system planets come with different sizes as we can see Job her is much more messy of down our earth about 300 times more massive than our earth and as a way know from the source to some architecture this giant planned this all very far away from our host star and this makes us intuitively and this driven our understanding of general General protrude formation because we can see this giant planets would require a lot of mass to build up and in all the way to acquire a lot of mess it needs to some material to stick them on a stick the substance substance together so they need to form in the area where water is in the form of ice and a water in the form of ice is sticky so it can help help the material together to form the John planets so people would expect this giant planets should exist very far away from the whole but that could then one talk to my an acquittal were trying to search for exoplanets that technology that's not a lot of people to find John planets far away from the host star one can only find a planet this giant planets very close to the host are so nobody expected that to they could find any planets.

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So it's a very courageous survey that they were doing and in addition I this often said Father preparation makes its own luck so to come back to a survey try to find planets with the size of Jupiter or even less than to return. The event looked a very clever instrument I love the spectrograph what's special about this instrument is it can reach a very high precision of only about 7 meters per 2nd about 16 mile per hour so this is installed in the around to me.

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Telescope or front so the telescope itself is quite small so the special graph is surely remarkable as we can see. For planetary systems they are really far away from us such as 51 Pegasi. And they takes light 50 years to reach out to reach us however even at this far distance with that special graph one can measure the movement of the star down to a very high precision for around only 16 mile per hour which is only slightly faster downhaul I would jiving a parking lot and so this high precision allows one to measure a very small movement of the star due to the existence of the planet around it and today thanks to the effort of doc to my ear this precision has increased down to the.

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2 mile per hour about one meters per 2nd at this 5 distance so if this doesn't blow your mind I don't know what will Ok. So what is the method they use to the pack the planet so they get the message video velocity which would have us the motion of the star as we can see when the planet Arbet around the star and the one the op ed.

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Is lining around the lying of sight we want to see the star to move away from us and to what's us when the star move away from us we can see the light could be yet shifted and the honest eyes moving towards us the lighter will be blue shifted so from this periodic Doppler shift one can tell the existence of the object pulling around the star and from the amplitude and period one can tell by there is a plan there and how far away the planet is from the host so here is the observational result by Dr my year and the clearly up for the discovery of 51 Pegasi So it shows the radial motion of the star as a function of the face because see the amplitude is about 70 meters per 2nd about who are 60 miles per hour faster than we would jobbing the highway but not comets and from this one can find that it's pulled out where the sides of the pond 5 Jupiter mass at these times corresponding to a period of 4 days and a distance of only 5 percent the Earth's sun distance so it's all we can really close and it has a mess we're very sure it's a planet So this marks the beginning of the discovery of planets around solar type stars as people believe now that plan is truly exist with this large sized very close to host Are people have the ability to really find them and characterize their features and we can see sings then many many planets are discovered.

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And you can see the number of actual planet discovered over the years grows exponentially and the in the 1st few years it's mainly discovered by the radio but also the mass audit we just discussed. And afterwards especially after the launch of the cabin our space telescope. A large number of perhaps a plan as were discovered by the Church of the man thought down by this calendar spacecraft.

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So that different color everything done before and detection man thought. And today. Today in 2019 we have more than 4000 planets discovered so what else does it help us in addition to telling has hammered out here with their exist around other stars they also present has a whole diversity of exoplanet population as we can see many of them absent from our own solar system including the hard job of hers as we discussed the massive plan is larger than the size of Jupiter very close to host our way the appearance of 10 days yeah also planets with a mass in between Earth and Neptune which could have very different in curious structures and this planets have very common in the universe however absent from also our system what does this tell us there is this our open question is awaiting for us to answer and I'd like to invite you guys sitting here to answer these questions together.

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And also based on this observation the results one can calculate of the occurrence rate of these planets so finally understand how common this planets are around other stars and indeed it is finding that the plan is sound quite common and it's also find that it's more often the tag smaller mass planets comparing with the larger size ones so next the discovery of $51.00 Pegasi be you get this into telling us the culmination of plan a is around the are waiting around the other starts it also devolution lies on their standing a planetary formation so for centuries before the discovery of the plan is around other stars people could only study the plan is reciting all solar system and they can't say they have very augured Opitz and the general plan itself for the way they sing spiled all understand in planetary formation and then we would expect John plan is to abouta very far away from the giant hole star and now we see that hard to be too it could actually for America close so as mentioned earlier this year the challenge is our understanding of planetary form and next very clever observational technique can measure the.

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Very detailed structure of the planetary system such as the spin off with the misalignment all of those stellar spinning and planetary Abi Titmuss that alignment as shown by the right side angle here. For all sort of system the misalignment is small and Ace can be understood in could have allayed because the whole system form inside a giant what I call a cloud which shared a common axis of rotation and objects falling there which shared a similar direction of rotation so the misalignment should be small for our own and that this farm sort of system the misalignment is a way of being 7 degrees hot over from a discovery of Jupiter's well how find that some of this large giant planets very close to the host are all bent in very different from the spin axis of the host star even after a while it had the grease so the challenging question is what can produce this misaligned hard to beat her so many research groups have started.

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Trying to answer this question including we here at the judge at pick so you women notice something not very universal about our own solar system nowadays around half of the Solid have Star have stellar companions living in binary is that our solar system doesn't have a companion so is it possible that a stellar companion can drive a spin over to me said Lyman and a car also helped produce this hard to beat so we can see that.

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We find if the planet has a near coplanar in a similar plane. Her stellar companion the star companion can flip our bit of the planet like flipping a pancake and as I live the distance between the plan they down the whole star can be a radius and her last has to operate and tied to a circularize them changed our bit and in the end we counting a misaligned Hottovy to a country view of him through the formation mechanism of the discovered misaligned how to be.

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Last but not least you can see that a discovery of 51 Pegasi baby opened new at Pollock of exoplanet House tries a mission which allowed us to search for the have civil wars around us and to better understand why they're well along in the universe so how do we do it so 1st fall 2 of the lowest order that we could understand so far lastly And as we understand it it's quite authentic aid it does not.

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Feel well for the last one on the planet if that's not so positive life while if the planet is very close to the host are when it's too hot and the their way to. The planet is too far away from the star so they can where the temperature is more comfortable suitable for liquid a what to take the stand the surface a planet it's a Qada have to pose them and this is a very important to life as we know it because most laugh us require water quality could of water to emerge and for life as we understand it it's a request of liquid water to exist so they use they said the definition of a habitable zone for as so planets so so far from this planet or discoveries we are already overturned he has a plan it's discovered that hierarchy and the living inside is have to oppose them so the pressing question for the is too so.

[00:47:18]
How do we identify those which are more favorable for life for better targeting for future observational missions and to select a once which may hold higher potential for life higher potential to be more habitable. So one of the ways to do it is to study the atmosphere features of this plan is to study the atmosphere composition and this can be found through the planets chess mission spectrum as the planet pass in front of the star through the transit method the light from the star will pass through the atmosphere of the planet and then the molecules in the planet a wordly of imprint in the light and which can tell us the atmosphere composition and the molecules existing in the atmosphere such as oxygen.

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Water as was carbon dioxide for instance and these signatures all together can help us better probe why the this planet is habitable for life and the many to search groups that have very interested in this questions including doctoring cards group whole study the past evolution of earth and apply this to excell planets and to identify the bow signatures that may indicate that emergence of life exoplanets and also my own group how to judge a path who are interested in the stability of the planetary system.

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Lacing and the climate of variations of exoplanets which also play a very important tool while planetary with ability So to summarize the discovery of 51 Pegasi be open a new ad hoc of characterize ation and discovery of actual planetary systems and tell it told us that are in the plan is around sun like stars and they are quite common and also revolutionized on their standing planetary formation a theory to help us understand that her unique miss and the formation origin of this planet's.

[00:49:29]
And it also kicked off the search for how the ball warts So in the future many missions will continue discovery and characterizing exoplanets around us so it's a very exciting time to understand better whether there will be worse thanks to the discovery of 51 Pegasi be a Dr Meyer and a cradle thank you thank you.

[00:49:55]
Thank you thank you. Yes thank you what is the method but uses to this by the Kepler Mission So this is they use a method called the transit method so this is based on the brightness variation of the host star so that they can detect as the planet chancet in front of a star on the planet more in front of the star along side so as the planet I'm moving in front of the start to come block area on the star surface so this can make the whole system look and as the planet appear out there clearly I would see that the mists of the system periodically and from this one can tell they exist and so plan is her around it and from that that the that the m one can tell the size of planet so they could know quite a lot of time does the microwave radiation came from the Big Bang radiates from some place like a point it actually radiates from everywhere in the universe so we're seeing that is is a sphere so it radiates a certain time period after the Big Bang and so that's radiating if you look at it that far away so if it happened say 400000 years after the Big Bang.

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It will write to us 13800000000 years minus 400000 years afterwards so it's coming from everywhere we're seeing that everywhere to us today. That it's rated everywhere so because if you think about it you know in the past when the universe was radiating the sea before that's how our day happened in the past if we think about today here but if you think 13800000000 light years away that light that happened 13800000000 years ago is just reaching us you have to think as telescopes as a time machine right we're seeing what's going on.

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I professed thank you very much for your talk. So regarding nucleosynthesis the models were very visually stunning Thank you. But I'm sure there are probably some assumptions that you're used to build those models so what experimental details are we missing to inform those models so what do we not know about nuclear synthesis that we're trying to find out so Beth then like the rates where you know you had some errors in the rates in which those actually occurred but then later studies there are some of the 1st actually study that So that was just refined over time and now that like the uncertainties and the Big Bang we get the synthesis is very right the errors are small and but the thing is like it only produces hydrogen helium and some lithium everything else is produced and we know like and over just generations of stars you build up these here elements over time but right now like from nuclear subs as at just after the Big Bang that's really very small errors and how do we know that people's Raul on the globular cluster Yes And what what do we now know about it yeah yeah I didn't go over that but but he hypothesized that those God were clusters actually formed 400000 years after the Big Bang but but now we see them actually forming they form during the merger's galaxies so you start forming the super star clusters that have 10000000.

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Stars and up and then then they are kind of flung out into the higher energy orbits that go around and they mainly form in mergers Yes because when they merge together you'll have this the strong shocks condensations of the. Professor wise I haven't really gone into I haven't really thoroughly researched this but I've been seeing some things floating around about a star that was discovered that supposedly older than the universe I saw that area your thoughts on that no yeah I thought so.

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So Ok so when you actually take the edge of a star so you basically look at the chemical composition and you look at a half like you can actually detect uranium in the atmospheres of stars and and you can measure the differences in the isotopes in your radium and you can get a get a made of age but the error bars on that is around a 1000000000 years so it's like you know plus or minus you can say like 13000000000 years plus or minus a 1000000000 years go up to 14000000000 years that's an order than you know so.

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I haven't seen that study by saw the headline but this has been played before it was always like I wouldn't think that researchers claim that they gave the error bars they actually said that but sometimes the media try to hype it up. I was wondering this may not be as important but why are the maps of the universe so oval shaped and other you know that's just a perception on the map and that's just so they're all sky maps so if you think about a a map like of the earth right that's just that's one way I think it's called a mole the wide project is just one way to look at $360.00 degree Griese on the sphere in a flat plane so it's not an actual like representation of the shape now so it's like looking at all all directions around us was their hand up we over here a couple exercise it.

[00:57:34]
So I remember you're talking about the cosmic web and like there being certain nodes where there are like a large closer and then state of stars are these typically the places where massive black holes are formed when these cosmic web steak intersect and have the stars there so that's a nonstandard question so it's still being studied right so super massive black holes they all exist at the centers of galaxies so whether that's a black hole forms before a galaxy or which one cursed you know sometimes it became happened before or after but usually right you have a galaxy in one of those nodes in the center of the galaxy others so they do co-exist because because you have 5 or 6 times more dark matter there it than there is gas so if there is dark matter there high density dark matter the gas is just along for the ride falls in that says form stars a galaxy and also black hole this may be more to philosophical but.

[00:58:36]
When By when do you think we will have to have found have it all and live on this is a very good question so we can see a lot of things. Are quite difficult to predict that test the existence of the planet around us and is today through this risque observations one find one so there are a few challenges in determining whether the planet is truly habitable.

[00:59:06]
So for instance through a lot of the bow signatures of that in this molecule a lot of the molecules can also be. Generated a balcony so there's still a lot of difficulties pursuing this path to actually find habitable planets but I would say through the discovery of actual planets it is the 1st time actually people come work on this topic scientific.

[00:59:34]
So I would guess just blindly bet probably cancer years all that country is all within 100 years has a very big day for the other magnitude so this is unfair of magnitude I would guess but I wouldn't be surprised if the beers breaks through through this very risky observation could find it so this is why I always thought about signatures the other ways through all of this light which could pass.

[01:00:05]
From technology based discoveries such as pollution areas which may have some distinct from the natural gas lines which could tell us the more civilized. Life forms in the off side of the solar system and also. Another way is they funny us so this also have a very large Certainty it's very difficult to answer your question for Dr Any 61st got to wear the ring if you watch experience all right if you have further questions feel free to come down and chat with our speakers let's give them a big round of applause thank you thank you.