Warp Drive and Aliens: Bryan Gaensler Public Lecture

[Music] [Applause] thank you good evening good evening and welcome welcome to perimeters stood here in Waterloo Ontario Canada and welcome to this perimeters public lecture series my name is Greg dick and it is a pleasure to welcome those of you here in in the theater and to our online audience and first before we begin in the spirit of understanding and learning from what has come before perimeter respectfully acknowledges that we are located on the traditional territory of the a Diwan from the ocean avec and the jota Shoni people's perimeter is situated on the Haldeman tract land promised to Six Nations which includes six miles on either side of the Grand River and for those of you watching online you can follow us on social media we're at perimeter and use hashtag P I live and you can follow an engage in conversation with scientists behind their keyboards during the talk and if you want to send questions to me use hashtag P I live as well and I'll have those questions ready to go for our presenter at the end and now it is my pleasure to introduce tonight's very special guest speaker dr. Brian Gaines ler dr. Gaines Lee received his PhD from the University of Sydney and subsequently held positions at MIT the Smithsonian Harvard and Sydney before taking his current role as the director of the Dunlop Institute for astronomy and astrophysics at the University of Toronto as the director of the Dunlop Institute in Toronto professor Gaines their aims to develop new approaches to astronomy while also training the next generation of astronomers he is a Canada Research Chair of astronomy at the Department of astronomy and astrophysics at the University of Toronto and the director of the Canadian initiative for radio astronomy data analysis dr. Gaines ler is co-chair of both the Canadian astronomy long-range plans 2020 and the Toronto initiative for diversity and excellence in his spare time he co-authored 400 scientific papers on cosmic magnetism neutron stars supernova explosions and interstellar gas and wrote a popular astronomy book called extreme cosmos which has been translated into six languages tonight dr. Gaines lair will share the latest thinking on insert on interstellar travel and the search for alien life and how the research may be even more exciting than the stories in our imagination ladies and gentlemen please welcome dr. Brian Gaines allure thank you so much for that welcome Greg and thank you to all of you for coming out here on this chilly night it's such a pleasure to be here as you've heard from Greg I've had the privilege to work all over the world and let me assure you that the premier Institute is something really unique and really special we are so lucky to have this place here in Waterloo and here in Canada and I'm thrilled to have been invited and to have a chance to tell my story here so so the very short version of my talk for for those of you watching that on YouTube you don't want to sit here for an hour is that warp drive and Aliens well I'm gonna I'm going to give you a spoiler we don't have warp drive yet and we haven't found the aliens yet but there are very exciting prospects for the future if you love science fiction then be patient and you will see your wildest dreams hopefully start to become real so I'm an astronomer and I love saying those three words so I'm gonna say it again I am an astronomer and I love saying that because I decided that I wanted to be an astronomer when I was about five years old and I've never wanted to do anything else and if I could go back in time to that five year old and tell him guess what you got to be an astronomer and it really is awesome I just cannot imagine how happy that would make him feel so it's the only thing I've ever wanted to do and it's just a thrill to know that I am getting to actually do that so why did I decide to become an astronomer well my parents bought me a lot of books I love to read and it kept me quiet so they bought me lots of books and I loved the books that my parents got me they got me books on dinosaurs and books on volcanoes and books on racecar engines and I just devoured them and I loved the fact that they all full of facts and they had answers to everything but then they got me this book that was quite different this book here I still have this book the album of astronomy and this book just totally changed my life because while all the other books were full of answers and that was great because I liked learning about these things this book was different instead of having answers it was full of questions it was basically saying we don't know what is going on in the universe there are so many mysteries and we just cannot figure it out and this was incredibly exciting to me for a few reasons first until that point I was only five I thought that there was no such thing as a fad as a question that people did not know the answer to that like humans some someone would know the answer to everything so I figured that when that my parents probably knew pretty much everything of course when I was fifteen I knew that was totally wrong but at five-o I thought I did in it for some reason my my parents didn't know the answer then my teacher would know the answer and if unimaginably my teacher did not know the answer then you know back in the 1970s we had these things called libraries and encyclopedia and I could look it up in encyclopedia and the answer would be there but what this book told me is that there are some questions that nobody on the planet knows the answer to and that blew my mind but the even better things that said but there are these people who figure out the answers to these questions and they're called astronomers and these astronomers take things from that we have no idea column and after a lot of hard work and brilliance they move them into the oh yeah we know what that is column and I thought oh my gosh that is what I want to do what's great when I look at this book now forty or forty-five years on is that the big big mysteries the we would give both our arms to answer their answers to these questions mysteries of the 1970s and now just mundane thing the answers are in every textbook these are not even remotely mysterious anymore all of those big mysteries have been completely answered 40 years on but now we have these huge mysteries in astronomy like what is dark energy what are fast radio bursts these massive mysteries that we didn't even know what the question was back then and now they're huge mysteries in astronomy and so I love the fact that you know we go from answering a question to asking a question to answering a question and then coming up with totally new questions and this process is happening all the time just to prove to you about what a hardcore astronomer I was at a very early age I'm gonna show you a picture from from about 1980 when my parents and I went to the equivalent of the Canadian National Exhibition I grew up in Australia so we obviously didn't have the Canadian National Exhibition in Australia instead we had something called the Royal Easter Show which is pretty much the same sort of thing and there was a cartoonist there who said I will draw a caricature caricature of you for $5.00 and I said I'm um dad please please can I have five dollars to have a picture drawn on me and they said okay here's five bucks and I sat down with the cartoonist and they said why don't I draw you doing what you're going to be when you grow up what do you want to be when you grow up and I guess they're expecting me to say fire fighter or airline pilot or all the usual things that little kids say and I said I want to be an astronomer and she said uh okay and she drew me as an astronomer and Here I am so you can see that I look exactly the same the only difference now is that my telescope is a whole lot bigger but I'm very fortunate to still have this cartoon from all these years ago because it reminded me of just how passionate I was about astronomy back then and nothing has changed so I love being an astronomer and I love astronomy but the only other thing that matches my passion for astronomy is my passion for science fiction so as science fiction is a bit of a touchy topic for astronomers half I'm going to grossly generalize here but half of astronomers lover and half of them hate it and the reasons why they love it and the reasons why they hate it are exactly the same it's because it breaks the rules astronomy is part of physics and physics has these beautiful laws that govern that explain everything from you know a butterfly to a distance they all follow the same rules so some people really don't like science fiction because they say look I've spent decades training to understand these rules you can't just go off and then you know make a movie where you just cheat and other people love science fiction cuts look I spent all day at work strictly following the rules when I get home I just want to let my hair down and break some rules and so I fall a lot a category I love science fiction because you know I know that the things in science fiction are impossible and they break the laws of physics but you know it's sort of that the rebellious part of me saying what if but apart from that there's two reasons why I love science fiction the first is that in a very profound way science fiction casts new light on what it means to be human if you read a good book or watch a good movie not not a science fiction story but just a normal movie often the reason why it's enjoyable is because you're seeing how human beings react to complicated emotional challenging situations and science fiction takes that to another level it puts humans in situations that you could never that you couldn't could never happen in you know the crown or downtown Downton Abbey but far more futuristic complicated situations that we're never going to experience on in everyday life and you can ask how do people respond to that so this is one of my favorite movies the last few years the movie arrival and so Amy Adams plays a linguist and she is reacting in this very complicated way to the fact that she has encountered aliens who look and think completely different from us and she's trying to work out how to communicate to them if you haven't seen this movie it's a very good movie very powerful emotional movie about being a parent and about memory and about life and death but it's all in the context of aliens landing and trying to talk to us and the questions that are asked in this movie are not questions that you could answer in just a contemporary piece set in Waterloo in the year 2020 unless you bring in the aliens so so I love science fiction because it allows us to ask important questions about the human condition and the other thing I love about science fiction is a lot of it it's about technology and as we know technology changes our lives completely in many complicated ways and it's going to continue to do so and so science fiction steps forward maybe five years or 10 years or 20 years and ask questions ahead how are these new technological changes going to change our life for better or for worse so here's another recent science fiction show West world where you know there are these high-tech robots that are basically indistinguishable from humans and we and it explores in a very complicated way you know what does it mean to be a living thing what does it mean to have emotions or feelings or thought and you know can robots be sentient so these are questions that we'll probably have to address in real life in 10 or 20 years but science fiction lets us ask those questions right now and prepares us for the future so there's fat and there's science fiction and some people think that they're completely separate and they have nothing to say about each other and I'm one of those people who thinks that they're very intertwined so if we even look up what astronomers are talking about and thinking about it can get a little bit hard to tell the difference between science and science fiction so let's look at some of the highlights of my field of astronomy over the last couple of years so one of the you know who could have thought this could possibly have happened moments happened about two or three years ago when we had the very first interstellar visitor from another star that we've ever been aware of it's not wasn't a night it wasn't aliens but you know what not the sort of visitor we might hope for it was a rock an asteroid and that drifted past the earth and it caught attention because you know there are lots of asteroids that we see all the time but they're all orbiting the Sun and this one was at a very severe angle at a very high speed such that it can't have been in orbit around the Sun it was coming from somewhere else and it approached the Sun at very high speed whipped around you know the Sun's gravity and then zoomed off out into interstellar space never to be seen again we gave it the name in Mulla Mulla and we believe that this rock was actually used to be an asteroid in some other solar system maybe on the other side of the galaxy and for tens or hundreds of millions of years has been whizzing across the great across the galaxy and just by sheer luck happened to a drift and trial solar system before flying off again so that alone is amazing the first time we've ever seen any object come into the solar system from outside of the solar system but what's more when we measured its shape it wasn't like a normal a steroid most asteroids are so lumpy you know vaguely around was sort of lumps and bumps on them but you can see here that a Muammer was very different it was mold shaped like a cigar it was dark and extremely long about ten times longer than it is why then that's a very strange shape so a lot of scientists were saying you know who could have thought of this this is like beyond science fiction but if you're a science fiction fan you know that this is not beyond science fiction we've seen this before probably the most well known time we've seen this is in the movie Star Trek for the voyage home that's the one where they go back to the 1980s and save the whales but this indeed exactly like in real life a dark cigar like alien probe comes from outside the solar system and travels to earth and interstellar visitor that looks remarkably like a murmur and even Star Trek wasn't the first to come up with this back in 1973 arthur c clarke wrote a novel called rendezvous with Rama one of the great science fiction novels of all time they haven't made it into a movie yet but they really really should and this one the plot is remarkably similar to real-life a cylindrical dark asteroid comes flying in from outer space on a very severe orbit and swings around the Sun once and then flies off before it does they check it out and it turns out that it's actually an alien space probe so the moon war is not telling us to save the whales and it's not an alien space probe but it's remarkable how science fiction actually anticipated the idea of this dark strangely elongated interstellar visitor so all right science fiction beat us to the punch on that one but come on like there's been so many discoveries lately there must be other ones that are that completely blow science fiction out of the water so one of the unquestionable discoveries of 2019 in fact most science magazines ranked this the number one breakthrough of 2019 was a spectacular image of a black hole so this is not an artist's impression or some clever sort of computer over interpretation this is an actual picture of a black hole and it was people here at the Prudy Institute Avery Avery Broderick and others that were absolutely instrumental in making this image so this is a black hole it's 55 million light years away the sharpness of vision here is ridiculous it's the same sharpness of vision that you if you if someone was sitting in New York reading a newspaper and you were in Paris this sharpness of vision is the same as being in Paris and having having a telescope good enough to read a newspaper in New York so it's a really remarkable breakthrough you know it doesn't get any better than making actual picture of a black hole but won't surprise you you know that you know I think you know no offense to our hard-working scientists here at the premier Institute but the black holes in science fiction you know they look much better than this has anybody signed up yet for Disney Plus like hands up have you joined Disney Plus anybody a few of you have you yet watch that a classic brilliant piece piece of art the 1979 Disney movie the black hole is anyone watch that I saw it when it came out in 1979 and I watched it a couple of weeks ago again and you know what it's still pretty good movie so here is a still from Disney's the black hole go out and and watch it if you can this is before I guess before Disney had the budget they had now this is actually a pool of water being stirred in a Plexiglas tank with dye added to it but even so you know I said no offense but it actually looks better than the real thing but that's actually not what black holes probably look like what you're seeing here if you could crank up the resolution even more and make a sharper vision which is which is what astronomers are now trying to do you should see something like this and this so this is a clip from interstellar and this was based on actual astronomical calculations made by nobel prize when he Kip Thorne using a supercomputer of what a black hole would look like up close [Music] [Music] all right so so that's Matthew McConaughey about to narrowly avoid destruction a black hole but with almost no artistic license at all that's pretty much what a black hole really looks like as far as we can tell and in the coming years we'll get sharper and sharper pictures of the real thing and it will start to look like that I guess one big difference between science and science fiction is how we name things this object's name is m87 star and the one here is called gargantuan so I don't know which which black hole you'd rather be sucked into but I'd far more like the drive into gargantuan that I wouldn't m87 stars okay so clearly science fiction was thought of everything but I did think of one thing that to the best of my knowledge has not been anticipated in science fiction there might be some science fiction fans here in the audience or online and if if you know some sci-fi that predicted this then please let me know I'm happy to be corrected but in August of 2017 something remarkable happened involving things called neutron stars so neutron stars are these some of the strangest stars in the universe they weigh more than the mass of the Sun but they're only the size of kitchener-waterloo they're like 25 30 kilometers across but they weigh more than the mass of the Sun so that some of the densest objects in the universe and if you think one neutron star is pretty incredible we'll imagine two of them orbiting each other and then crashing into each other and that's what we saw in August of 2017 so here's an artist's impression of what we saw two neutron stars spiraling in faster and faster and then eventually coalescing possibly forming a black hole and creating a spectacular explosion well we didn't see the moment of the explosion itself because we didn't know it was about to happen this explosion actually was so violent that it made the entire universe shake it's like the granddaddy of all earthquakes so we live that universe is a mixture of space and time space time and the actual fabric of space-time itself vibrated across the entire universe when these two neutron stars merged and we actually felt that happen you and I didn't feel that happen you weren't sitting there eating a sandwich on that day and think Oh what was that but we have the vibration was tiny it was like smaller than diameter of an atom but we have these incredibly sensitive instruments one in Washington and one in Louisiana called LIGO and they detected the vibration from these two neutron stars merging and literally the entire universe shook for a few seconds after that which is quite extraordinary as I said I'm pretty sure that this is one thing that didn't turn up in science fiction before it happened in real life but if you know better I'd be happy to be corrected okay so science fiction is normally ahead of the game and you know given that my talk is on Ward Drive and aliens it's not going to be a shock to you to tell you that science fiction is ahead of the game here too so warp drive is really all about traveling from one place to another quickly we know that stars are unbelievably far away the nearest star to us is 40 trillion kilometers away so getting from one star to another is not super practical and in science fiction you sort of want people to be able to go to other stars to travel around and have adventures so you have to have some some cheat some way of getting from one star to another and normally science fiction doesn't worry about the details too much they just invent warp drive or hyper drive or something and that's just a convenient way of getting from A to B so in in the movies it's super easy to travel from one star to the other so here's a scene from Return of the Jedi Admiral Ackbar may he rest in peace and here we go traveling from one star to another [Music] so easy and they pop out pop out two seconds later and they're at another star system so of course in real life I'm not giving away anything to tell you it's not that simple so if we want to be able to you know live the life of science-fiction and travel to other stars how might we actually do it so old-school science-fiction is you have a rocket ship so here's a real rocket ship and here's a science-fiction version could you build a rocket ship and use it to travel to another star so the short answer is not really the way the Space Shuttle worked is it has it's full of fuel and you light that fuel and you get a massive explosion you direct the explosion out the back and the gas flows out that way and you get a reaction if you push the gas up that way you go that way okay so it's very simple brute force technology and it pushes the space shuttle up into space now the space shuttle is really really big who's actually seen the space shuttle at one of the museum's anyone's seen it it's huge right and if have any of you been to the one in Florida where they actually had the boosters as well anyone been to Cape Canaveral it these boosters are even bigger than the space shuttle so you get a feeling you've got this massive multi-story building just full of rocket fuel and that's what you need to launch the space shuttle but the space shuttle and this is sort of a bit embarrassing because it's not really a space shuttle it doesn't really it barely goes into space the space shuttle only went up 300 kilometers that's not even from here to Ottawa so it's a very short distance and that you needed all this incredible fuel just to get 300 kilometers above the Earth's surface so you still haven't even escaped from the Earth's gravity let alone escape the Sun let alone travel to another star so even if you could build a rocket that you that had everything you needed on it to travel to another star and you built the fastest rocket that's ever been built it would take about 20,000 years to get even to the nearest ER so not only does that not make for great TV on a science fiction movie it's obviously not very practical if you want to travel 20,000 years that's you know many many generations you'll need thousands of people and food and radiation shielding and school and all the rest of it you're gonna have a spaceship beside bigger than a cruise ship and that's just not practical if you really cut everything down to the bare bare bare minimum you could pass the calculations have been done that you could build a very small hyped up superpower rocket that could get to the nearest star in 900 years it's still a pretty long time and there's a few problems with that firstly that's to get to the star but of course you're travelling very fast when you get to that star and you've used up all your fuel so you have no way of slowing down so you finally get the star it's like bye and that's the end of that so not very practical but even that would take 900 years and what's more you'd need more matter than there is in the entire solar system to do it and so you can imagine how big the rocket boosters would have to be so while I love pictures like this it's just simply not never going to be a practical way of travelling between stars just the amount of fuel you need is just completely impractical so let's look at options that don't require so much fuel there's another alternative called the ion drive it sounds like science fiction but it's actually real and it simply involves using electricity like a battery or something even nuclear-powered or solar powered electricity to slowly evaporate a lump of fuel and gently blow out your fuel at the other end so you use much less fuel but you shoot out the individual ions much much faster and so this is an artist's impression of a satellite probe called dawn that was used by NASA and it visited two asteroids Vesta and serese-- and it traveled six point nine billion kilometres over eleven years and it traveled that six point nine billion kilometers using only 400 kilograms of fuel so that's nothing like that's it the big block of fuel about this big they use xenon so just a big tank of xenon gas weighing 400 kilograms which is not that much compared to the space shuttle and that's all it needed to travel billions of kilometers over 11 years and if you think that sort of looks too good to be true like this just looks like its artistic license and there's nothing really like that here's a photograph of an ion drive in the lab and it looked exactly like the artists impression so these things actually work and they've actually been many satellites now that have flown around the solar system using the ion drives the problem with the ion drive is that it's really really weak it's a very gentle thrust so if you're shopping to buy a fancy car or Porsche or a Lamborghini it might be important to you to know how fast it takes to go from zero to 100 and the most expensive cars that you can buy these days go from 0 to 100 and a little less than 3 seconds so if you walk through the showroom and point to the NASA dawn and said what can I get out of this baby well the answer might disappoint you because it goes from 0 to 100 in 4 days so the acceleration is really really weak it takes a long time to get up to speed so that's the price you pay for not having to need much fuel is you don't get a lot of oomph out of it and so if you tried to use the ion drive to travel to another star even to the nearest star it would take you 80 thousand years to get there again not very practical there's another problem as I said the ion drive is super weak so you could not put this thing on the ground and say ready for takeoff three two one go nothing would happen it's too weak to escape the Earth's gravity so you still need all of those rocket boosters to get it out of the Earth's orbit and only then can you turn on the ion drive so this is probably not a very practical solution either what about if we get rid of the engine completely and use an energy source that isn't attached to the spacecraft could this solve our problems so this has been thought of too it's been around in science fiction for a very long time and the idea is to use what are called solar sails and the theory here is that the Sun actually is blowing off this gentle wind in every direction the solar wind that's traveling at quite a high speed these flow of particles in every direction so as long as you want to travel away from the Sun and not towards it you simply have to unfurl a big sail and it will fill up just like the sail of a ship and you'll be blown away from the Sun and just like a sailor you can use various tricks tacking and all the rest of it if you don't want to travel directly away so here is a solar sail being used by Count Dooku and Star Wars Attack of the Clones and here is sort of the classical old-school 1950s science fiction version of a solar sail so could we use a solar sail to sail the solar system on the sun's wind and the answer is well maybe there's also memory the problem I mentioned before is having to slow down when you get to the other star well it's perfect you use the sun's solar wind to sail halfway to the so you're going to then you turn the whole thing around and you use the wind of the other star to to slow down and then you go to a gentle stop when you want to go there so people are actually working on this technology here is a spacecraft called light sail - that was developed by the Planetary Society the space probe itself is really really tiny it's just in there it's only about this big but the sail is huge it's about 30 square meters or about 350 square feet so this thing was actually launched about six months ago here it is this is a photograph from the probe so you can see this is Baja California down here in Mexico in the United States this is the probe and here is the actual solar sail unfurling so this was in June of last year so of course the big question is does this actually work and the answer is yes it does so left they unfolded the sail and they measured whether the sun's wind actually pushed this satellite into a new orbit but the results are not exactly spectacular so this is before they unfurled the sail it was seven hundred and twenty five point six kilometers above the Earth's surface they opened the sail right here not much happen for a few days but then very gently the solar wind pushed it to seven hundred and twenty seven kilometers above the Earth's surface so this is the first time anyone's really done this and it did work it raised the orbit of this spacecraft by one point eight kilometers you want to start somewhere so clearly we have a very very long way to go here there's lots more technology we have to develop in order to be able to use solar sails and the sails are going to have to be much bigger they got to be hundreds of kilometers across and then you have the whole technological problem how do you pack the sail up when you launch the thing how do you unfurl it how do you spin the thing around what happens if like a meteorite rips a hole in it there's all sorts of huge challenges but if you can work out how long it would take to get to near a star using solar sailing and the answer isn't actually too bad it's only 75 years now that's still a long time it's you know you're not going if you start as a young man or woman at the beginning you're probably not going to be alive at the end of it but 75 years were actually starting to get into the right ballpark unfortunately there's really no way to go any faster you can't you know crank up the sound or crank down the Sun the Sun is the Sun and it gives out wind at a particular speed but there is at least a way that you know is it is not completely science fiction because we're it works over 1.8 kilometers we just have to get working over 40 trillion kilometers and we are in business and we can travel to another star using no fuel at all in 75 years but maybe we should be thinking outside the box and thinking a bit harder well there are some other options one that comes up a lot is this idea of something called the emdrive or the Mach effect thruster then anyone see this show last year's salvation you want to see this probably you're probably not admitting you want to see because it was really bad filmed here in Toronto though and there was a lot of Technology in it and one of them was this idea of this emdrive and the idea here is a little bit hand-wavy it you you inject microwaves into this cavity and they bounce around but they bounce around they bounce out fast slightly faster at one end than the other and you get a tiny amount of thrust the only problem is is that you really you know the laws of physics say that you can't get something for nothing and most people including me think that this breaks the laws of physics people have claimed that it does produce a thrust but other people have rebuilt the same experiment and haven't been able to produce it so this is probably complete fiction but you know if we can somehow get this to work then it does perhaps maybe if you don't mind breaking a few laws of physics produce a tiny tiny tiny amount of thrust so you know can this go fast enough no does it work no does it abate the laws of physics no but you never know okay are there other options again let's think outside the box maybe you shouldn't travel there at all wouldn't it be easy to get to on a star if you simply look at me you break me up into pieces I've got an arm and some here and some feet you pack all that up you transmit that information to the other star and then you put me back at the other end that's all an email is right I mean if I send you an email the Kiester it's not the key it's the keyboard doesn't get sent over to you the computer records what the keystrokes are it remembers the order I typed them in and it puts back that information at the other end over the Internet and you get the message that I sent you so you know this has a technical name it's called teleportation and maybe this is a way to get from one star to another so no rocket fuel is need at all you just have to break me apart into pieces and beam a signal and put me back at the other end and of course this has been a staple of science fiction since forever and of course that the most famous example will have teleportation of course is in Star Trek [Music] okay so in that case they're probably only teleported over a few hundred or a few thousand kilometers but if it works over a few thousand kilometers why can't it just work from one star to the other so the good news is that teleportation is real the bad news is at the moment we can only teleport one atom at a time but in Israel and it's called quantum teleportation in real life if you want to look it up and the record for teleportation at the moment involving one atom is teleporting over 14-hundred over a distance of 1,400 kilometers it was a Chinese satellite call me kiyose and they take teleport they teleported an atom from the ground up to the satellite so the actual after I've never moved all you do is you take one atom and you measure its exact properties and by measure in the process of measuring its properties you actually mess it up and you lose that information but you can transmit that state to the to the spacecraft and you can recreate an atom exactly the same so the atom at the end is AI is indistinguishable from the atom at the beginning tolerance to intents and purposes it's teleportation turned out to be really useful it's really important in cryptography and sending uncrackable signals which is very important in finance and banking and all the rest of it but can can this be used to teleport humans well probably no and probably not ever there's there's a few caches to this in terms of using for interstellar travel the first is that you need a receiving station so you've got to get your receiving station to where you want to teleport to first so if you want to visit the nearest star by a teleportation you've got to get a receiving station to the nearest star first and then you go back to all the problems I just discussed that has to get there through the normal means but once you've done that you're in business and you don't just simply have to scan every aspect every atom of a human being and transmit that and that's a bit of a problem because you can calculate just how many how much data you need to describe a human being an exact copy you really want to be exact copy right you don't want to teleport there and discover something important missing so the amount of data you need to scan one human is 300 million and trillion trillion gigabytes that's that's three with 32 zeros at the end of it gigabytes so that's that's you know a lot of memory sticks and then if you work out well okay now you have to transmit with a radio signal you have to actually send that signal to that's there well at the highest data rates that we have at the moment it would take you five thousand trillion years to transmit that information which is 360,000 times the age of the universe so it would actually be quicker to walk to the nearest star than to teleport so I'd say there are significant barriers to that teleportation does not violate the laws of physics unbelievably it doesn't we can do it but the practicalities of transmitting even a single human being are absolutely enormous so I don't think we'll be teleporting anytime soon all of these methods also suffer from something else and that's another catch is that you can go really slow and it can take you a thousand years or whatever if you could figure out using one of these methods going really really fast suppose you could build a rocket ship that could travel at half the speed of light or 80% of the speed of light or 90% of speed of light you'll get there faster but you then have another problem and that's something called time dilation it's a consequence of Einstein's special theory of relativity and what it says is that when you go really fast your clock runs slower than the rest of the universe and time dilation hasn't come up too much that's that been really super nerdy science fiction so you have to dive really deep to find it until Matthew McConaughey malong and saved the day as he always does in the movie interstellar we see time dilation Matthew McConaughey as a young daughter he goes off gallivanting around the galaxy and visits black holes and all the rest of it but despite being an advanced NASA astronaut didn't seem to know about time dilation he must have been sick that day because he's rather surprised when he comes back to earth and you know a month has passed for him he's still gorgeous and his young daughter is now an old old lady and so this is a real effect we have demonstrated this with clocks flying clocks at high speeds comparing to clocks on earth and they're very slightly different so even if you traveled if you traveled said only half the speed of light which you can go a lot faster it's like a 15 percent effect so if you were away for say ten years everyone who would be away for 12 but if you want to get picked somewhere first so if you want to go at 90% the speed of light it becomes about a factor of two and if you want to go at 99% of the speed of light becomes a factor of seven so if you went it not if you went on a journey to other stars at 99% of the speed of light then you might think you're away for 10 years when you come back 70 years surpassed so all your friends are aged or died technologies particularly a completely different society is completely different your total fish out of water so if you're given the chance to go on interstellar travel at high speed it might be the trip of a lifetime but it's going to be very lonely and confusing and strange when you come back maybe there's one way around all of these things and that's of course in the title of my talk warp drive so warp drive is a staple of science fiction and we saw it in in the star wars clip that I showed at the beginning with Admiral Ackbar but it was also a valid scientific idea and so the idea was developed by a Mexican physicist Miguel Alcubierre and he is science fiction fan and but thought about you know how could you actually do this in real life and the idea is that space is actually can be stretched and squashed I can't do it just with my hands like this for under the right conditions you can stretch and squash space and you can use that to actually move from one place to the other without using any rocket fuel at all so the idea is that suppose I have a big rug and I want and I put a toy car on my rug all the way over here and I want to get that toy car over to me standing over here so one way I can do it is I can walk over the toy car and I can hold it and I can wheel it across the rug to me so that is like a rocket ship using up fuel but there's another way I can do it I can put the toy cat on the rug over there and then I can just grab the rug and I can bunch up the rug and pull it towards me and then the car will eventually get to me the car as far as it can tell has not moved at all the wheels have not turned it hasn't had to use any energy and yet the car has traveled from over there to over here and that's exactly the idea behind warp drive except it's using actual space instead of the carpet that's the idea is you have some sort of spaceship it doesn't have to any feel at all but if you squeeze the space ahead of it and stretch the space behind it you can actually move it from one part of the universe to another in principle as fast as you want without using up any fuel now of course you have to use energy but the energy doesn't have to actually be on the spaceship so this is in principle a way of traveling to other stars without having to worry about time dilation or huge amounts of fuel or anything there's only one small problem we have absolutely no idea how to actually squash or stretch space-time and if we did it would require more energy than all the energy on earth put together but other than that minor detail this is theoretically possible and you know there with something is theoretically possible you know what they say you know where there's a will there's a way maybe thousands of years from now the Alcubierre drive will become reality okay so this has been a bit of a downer I've told you all the ways in which you will never visit other stars but all hope is not lost I'm going to finish this part of my talk by telling you one way in which we really might be able to visit other stars and this is a program that is a real program that's in its early days it's probably only about five or ten years old called breakthrough starshot and what breakthrough starshot says is let's forget humans traveling to other stars that's not going to happen any time soon and let's forget sending some giant space probe to another star but what if we had a space probe that was only this big if you have a space probe that's only like you know the size of a grain of rice then it doesn't need much fuel at all to to get to another star and well how you can actually get it going quite fast in lots of ways and of course the best sounding way and the way they're proposing to use it of course is using giant space lasers so the idea is is you have your giant space lasers here they are all ready to shoot their laser and then somewhere above into a floor but you have a tiny little spacecraft which is right at the center here with a big sail around it and then you fire up your space lasers you aim them very very carefully and you focus them all to exactly the right spot and they hit the sail here we go and accelerate this tiny little probe after a normal speeds after 20% of the speed of light or about 60,000 kilometers a second at that speed you can travel the nearest star in 20 years you can't slow down but you fly past that start great speed you've got just a few minutes to take a few snapshots hopefully they're in focus and you're pointing in the right direction and if there's a planet there then you get a couple of snapshots and you beam them back to earth before flying out into the void forever so it's not the same as being there just getting a few postcards but it's better nothing and this is perhaps the only viable way in our lifetimes we will travel to another star as I said these space lasers could accelerate that tiny little spacecraft up to 20% of the speed of light and at that speed it takes 20 years to get to nearest though you have to wait a little bit longer than that because the nearest star is 4 light years away and what that means it takes 20 years for the spacecraft to get there and then when it takes that photo and beams it back to us using radio waves it takes another 4 years for the signals to get back to us but from launch to getting the picture is about 24 years so that's that's not too bad you know hopefully most of us will be around in 24 years and you'd actually get to see the results so are we ready to do this well not quiet there's a bunch of different problems to solve like building giant space lasers but probably the biggest challenge is in having that tiny little probe and there is work going on in this this is called a femto satellite because we already had micro satellites and nano satellites so we had to go down to femto effect those satellites this is a real satellite it's called kick set it's about three centimeters across and it weighs four grams and it has all the basics of a space probe on it it has solar power it has a few probes to measure whatever it's flying past and it has antennas to transmit its signal back to earth now this is still not something that would be suitable for breakthrough starshot all these electronics are exposed if you shone a space laser onto this it would melt but if you could develop something that was even smaller maybe ten times smaller and which somehow I have the power to with a tiny little antenna to transmit its signal from 40 trillion kilometers away and take a photo and all the rest of it then you might actually have the sort of mini satellite that could be part of this experiment but there are more problems to solve and that's even if you got the space laser and you got your tiny little probe and you accelerate it up to the 20% of the speed of light you have another problem and that's that space is despite its name it's not space at all space is not empty the galaxy the Milky Way is full of dust and when I say - I mean dust I mean little grains of sort little little specks and flecks of junk and you can see that in the night sky if you go out on a dark night you'll see the Milky Way but you also see these dark patches and these dark patches are dust clouds that are blocking out the light from beyond you might say well you know that's that's annoying you don't want to fly into a dust cloud but you know there's lots of parts of the sky that don't have dust clouds well that's not true these are only the very densest darkest clouds but if you look in infrared vision you can actually see that the dust is everywhere so this is another look at the sky using a satellite called Planck that a bunch of Canadians were very heavily involved in and you can see that there is dust over the entire sky so everywhere you try and go in space there is dust now if I'm walking through space at these speeds that dust isn't going to bother me at all you know I might get a bit of soot in my throat or I have to sort of wipe the soot off my furrowed but it's not a big deal but if you're traveling at 20 percent of the speed of life then every dust grain that hits you hits you at 20 percent of speed of life and even a microscopic dust grain wearing a tiny fraction a gram is you know a sledgehammer when it's traveling at twenty percent of the speed of light so people have asked the question well what happens when you have a mini space probe traveling at the speed and you get hit with the dust grain so I'm going to show you a highly technical sophisticated calculation so this is the before shot dust and spacecraft and this is directly from the scientific paper you get bad words where bad words like crater and molten matter so if this tiny little satellite gets hit by a dust grain is a fair chance that the satellite will get vaporized so how do you get around this problem well there's a few ways one is you do not launch just one satellite with your space laser they're tiny one why not you know don't launch one launch one hundred thousand of them so the idea is you have this huge cloud of these tiny little rice grain size spacecraft and you know if 80 or 90% of them 99% of them get knocked out by dust grains it doesn't matter because only need one to get to the nearest us the other thing is you could put shielding around them it makes them a bit heavier and a bit more complicated but maybe the shielding will sort of slowly get blasted away by the dust grain and the spacecraft will survive or maybe you don't make them like square you make them like a needle shape and that way their cross-section to the dust is very very small so we haven't solved this problem yet but people are thinking about it and you know if you go back to that fantastic vision of all these spaceships slamming into warp-drive maybe the reality is tiny little hair sized space probes dodging dust grains as they zip over to the nearest ER alright so why don't you actually want to go to these other stars well the answer of course is because you want to see if there are aliens there we want to see if we are alone this is the you know the biggest question we can ask it used to be a philosophical question but incredibly it's now a scientific question is there anybody else out there and of course if there is anyone else out there we hope that they would be intelligent and we hope that they would be friendly like an et or The Day the Earth Stood Still and we really hoped that they wouldn't be mean like in War of the Worlds or in Independence Day so we don't know as far as we know we have never found any life on any other planet anywhere except our own and the reason why it's because finding life elsewhere is really really hard let's assume it's not it might not be a perfect assumption but let's assume that if there is life out there that it comes from a planet then maybe there's life that is an associate of planets but you know our life's on a planet so we have to find other planets and that's really really hard because planets are really really faint and even our biggest telescopes have trouble finding them this is a very famous photo it's called the pale blue dot it was taken in 1990 by a spacecraft called Voyager 1 that as it was about to leave the solar system just turned back and just took one final photo back from where it came from it's a photograph of the Earth from a distance of 6 billion kilometres can you see the earth it's that one little pixel right there so that is the planet Earth what it looks like from 6 billion kilometres away so it's quite sobering to realize that you know every person who's ever born and died every happy moment every sad moment every sports victory every tread every piece of music ever written everything that anyone has ever thought as important is all happening on that one little pixel right there so that's pretty faint you have to know exactly where to look to see it and that's the Earth from the edge of our solar system if you went to the nearest star and turned back and tried to take a photo of Earth well that's six thousand times farther away and a physical law call the inverse square law says that the brightness goes as the square of the distance so if you try and take a photo from six thousand times farther away the earth would be 40 million times fainter than that so I don't have to work very hard to convince you that if you made that 40 million times fainter you would not be able to see it what's more if you go from far away then you know the Sun is you know over there somewhere but if you go farther away then the Sun and the earth are right next to each other and the Sun is about five billion times brighter than the earth so put something five billion times brighter in the earth there and make that millions of times fainter and you can see that would just be absolutely impossible to see the earth so how do we find planets around other stars there are a few cases where we can actually make pictures like this and I'll show you one later but the way we normally do it is a sneaky technique called the transit technique and so these planets are on other stars are called exoplanets and we can't see them directly but sometimes their orbit is alone such that the planet drifts in front of its parent star relative to us and when that happens we can't see this we never see this we don't have the sharpness of vision to see this but there's the planet and it blocks out a tiny amount of light from the star like less than 1% but the star just gets dimmer for a few minutes and then as the planet moves off the other side the star gets brighter again so we just measure the brightness of stars very very carefully look for little dips in their brightness that are happening at regular times and that is a planet going around the other star and that little dip carries an enormous amount information and we can actually work out the properties of these stars so using this very simple technique we have found thousands of these exoplanets I looked up in the in the database this morning of the NASA database and the current tally is 4116 exoplanets that we know of are in other stars and the remarkable thing is that these planets are so so different from our own solar system so this is an animation showing you this is our own solar system so the sun's here Mercury's orbit Venus Earth Mars Jupiter Saturn and superimposed on that are just some of the other exoplanets that we know about and you can see that their orbits most of them are much tighter than ours and there all sorts of different ones some are going ridiculously fast some are going slow but they're all different and most of them are much smaller than our solar system so there's lots and lots of planets out there and they all have very different properties from from ours so let's go back to science fiction from her and say what a science fiction say I mean lots of science fiction there's a planet just like the earth it's very convenient for very cheap for filming purposes this very planet looks like California but but of course in some science fiction there are planets that look nothing like the earth and so you know here are a couple of my favorites this is Mustafar the planet at the end of Revenge of the Sith where obi-wan Kenobi and Anakin Skywalker have a lightsaber battle on this lava planet and yet this is strictly speaking is another planet it's earth but it's it's very science fictiony possibly one of the worst movies ever made Kevin Costner in Waterworld but he lives on up he lives on a planet where global global climate change has created a planet with no earth no land masses at all just water so you know in science fiction we have lava planets and we have water planets is there science fiction or is this actually some basis in fact well it turns out there aren't a lot of planets out there that we've found yet that look much like the earth but we have found planets made of lava and we have found planets that are completely made of water these are not photographs these are artists impressions but our best understanding is of those or the properties of the stars so you know the Mustafar and water world are real there are really lava planets and water planets but there are things that even science fiction hadn't dreamed up one of the most common types of planet in the universe are these hot Jupiters these are systems that have a planet like Jupiter but they're super super close to their parent star they're like 10 times closer to the star than mercury is to our Sun and instead of orbiting in months or in years they orbit in days or even hours and sometimes they're so close that the Saheed of the stars actually slowly evaporating the planet we have actually found planets that a pity you made entirely of diamond and perhaps one of the most common types of planets are these planets called super Earths their planets that you know are perhaps about the same temperature as Earth and maybe have the same conditions but they're much much bigger so here is Earth and you get these planets that are sort of earth-like but you know three or four times the size but what are the most common planets in the universe the most common planets in the universe as far as we know are those are in orbit around a particular type of star called a red dwarf red dwarfs as the name suggests are red and small and they are the most common type of star in the universe 70% of all the stars in the Milky Way a red dwarfs you might say well that can't be right because I walk out on a nice theory night and I don't just see all these red stars and that's because they're so faint even though 70% of all the stars in the Milky Way are red dwarfs there is not a single one you can see with your naked eye they're everywhere there's lots of them in us in our 20 of the 30 nearest stars there are some red dwarfs and you can't see any of them do you make a dime but these stars are very common and they have planets going around them and although they're quite dim and faint and so you might think they don't want might not produce much warmth if you put a planet close enough to the red dwarf it actually produces enough heat enough light to perhaps make a planet livable and recognizable to us so maybe this is the scene from a planet a bit like Earth but orbiting a red dwarf you got oceans you've got a shoreline but everything is red there's one way in which these planets be very very different from Earth though and that's as far as we can tell the planets that we're finding around red dwarves are what we call tidally locked that means that they always keep the same face towards their parent star now we see this in our own solar system the moon is tidally locked to the earth the moon always keeps the same face towards the earth the moon is a sphere and it has stuff on the front and the back but you can go out always and see the moon and it always looks the same with the same craters in the same spots because it always keeps the same face towards the earth we never see the back of the moon and so a planet orbiting a red dwarf would be tidally locked so one side would always be facing the red wall and one side would always be pointing away and so the conditions on a Red Dwarf would be very different from Earth you never see a sunrise or a sunset the Sun the star never moves if you're standing in one place thus the light will always just sit at one place never moving in the sky so it will always be a tunnel daylight or eternal darkness this is the side in eternal darkness it's pointing away from the star facing into space and so this side of this planet would be unbelievably cold and perhaps uninhabitable and depending on how close it is to the star this side face right above it where the red dwarf is right here it might be very hot and unpleasant and so it might there might only be sort of a narrow band here which actually is livable this ways too hot this Way's too cold but there's going to be somewhere in a band on the red dwarf planet that might be just right we found these planets and we think that's hardly locked and maybe they look like this but how do we actually know that these red dwarves planets actually have life on them and that gets really really hard the way we could do it is to look at the color of the planet because what happens is the molecules that correspond to life actually block out Swallow very specific shades of very specific colors a more technical way of saying it is if you take a spectrum of one of these exoplanets there'll be very specific colors missing and if the right colors are missing that would be the signature of life and we call those signatures bio signatures and here is sort of a simplified version of a spectrum so this is the brightness of the planet versus color going from indigo through to red and this is how much signal you've getting and so you can see that there are these particular places where the colors particular shades like this particular shade of red or this particular shade of green are missing and if the right shades are missing that means that things like photosynthesis or or methane or ozone are in the atmosphere of these planets and to the best of our knowledge those would be the seniors of life so the goal is to make a spectrum to look at the colors of that exoplanet very very carefully and see the signatures and the molecules that might correspond to life but this is really hard this is sort of an artist a simplified artists impression if you do a computer calculation a real spectrum might look like this so you can see these dips these missing colors due to the molecules that might correspond to life so that's sort of what it should look like and if you take the world's very best telescopes and you use them for incredible amounts of time you get something that looks like these black dots here and you can see that this is pretty crude it doesn't look anything like this and you really don't want to say oh this little bump here is proof of life it could be many many different things so we need bigger telescopes we need to collect more data and get a spectra to turn the quality of the data from this into this and so astronomers are doing that we're building telescopes both to go up into space and on the ground the goal of which will be to look for these bio signatures so one of those telescopes that will hopefully be launched next year is the James Webb Space Telescope this enormous sort of success of the Hubble Space Telescope that will have some capacity to look for bio signatures and then on the ground we're building these truly mammoth telescopes this telescope is called the ELT which of course stands for the extremely large telescope I'm not making that up the mirror is 39 metres across you can see cars here for scale this thing is absolutely enormous and it's being constructed right now and it will be ready to go in about 2025 which is not that far away and these are the telescopes that we hope will have the sensitivity to see perhaps the first bio signatures in the coming years now you might be thinking well why are we putting all this effort into looking for life around these distant planets and around other stars because we've got all of these planets right here in our own solar system is there any life on in our own solar system besides Earth and the answer is maybe we know that on earth water is important for most forms of life so the first thing you might ask is is there liquid water anywhere else on the solar system and the answer is is that on the surface of a planet or a moon there's perhaps only one place where maybe there is liquid water and that's Mars and I'll come back to Mars in a moment but underground there's a whole heap of moons of other of other planets that have oceans underground and the most spectacular one is Europa Europa is a moon of Jupiter and it as far as we know the entire planet is enveloped in an underground ocean and while you rope is quite small it's only a few thousand climbers across its oceans are unbelievably deep so the average depth of the oceans on earth is about three and a half kilometers the depths of the oceans in Europa 60 to 150 kilometers deep and what that means that Europa actually has twice as much water on Europa then there is and all of Earth so the place with the biggest oceans in the solar system is not earth its Europa we believe that that ocean is made of salty liquid water and that's where life began on earth in the oceans and so perhaps we don't know but perhaps beneath the crust of Europa there is life this is just an imagination of what might be down there we don't know because we haven't been to that ocean but maybe there is life on Europa maybe it's intelligent but because it's beneath the surface it doesn't know about us and we don't know about it we're very keen to find out more about Europa and the conditions in that and so there are space missions being prepared that are going to go to your Oprah and check out more one of them on the left here is this these are both artist impressions this is a European mission called deuce the Jupiter icy moons Explorer it's going to be launched in 2022 and it will arrive at Europa in 2029 and this is a NASA mission Europa clipper it's going to be launched in 2025 and arrive in 2030 and those are going to study Europa in great detail and try and understand the properties of the of the ocean and what's beneath the crust of Europa and perhaps also send a probe down to drill down and see what's going on we got a surprise about a year ago much closer to home on Mars that the planet that's it's not a particularly hospitable planet but it's the one that has the conditions closest to Earth you know it's remark Terry Ron this time of year that there are many days in the year when it is warmer on Mars than it is on Waterloo and recently the Curiosity rover found some rocks it broke apart the rocks and found some what are called organic molecules or sort of molecules that are produced there's waste products by things like bacteria so it found things like benzene and toluene and propane these sort of molecules that at least on earth are produced as a product of life so I didn't actually find any bacteria we don't know where those molecules came from and maybe there's other ways to make them but we have seen some evidence for these molecules on Mars so maybe there is some very simple life on Mars so here all these ways of looking for life bio signatures and molecules the rest of it but there's a much easier way you can just shortcut all these steps and just say look if there's an alien waving to us saying hello then the answer is yes there is life out there and so another thing that scientists are doing is the search for extraterrestrial intelligence or SETI and this involves listening to the sky for radio signals looking for another and alien actually sending a message to us so it might be Morse code it might be just something very simple it might be a piece of music it might be a message it might be a complicated broadcast but scientists are using some of the biggest radio telescopes on the planet to search for signals and this is an incredible needle in a haystack problem you don't know which star is transmitting from and you don't know when maybe the aliens only transmit for one hour every century we don't know so you're really just hoping for the best and the other big thing is you don't know what frequency to listen to if I went up to you and said ah check it out there's this really good song on the radio right now the first thing you're going to say to me is which station and if I say I don't know then you're going to have to go through every single station on the FM and AM dial looking for my song and by the time you get there perhaps the song is over well that's the problem we have we have no idea what station to listen to so you have to cycle through every imaginable radio frequency searching for that signal so so far they haven't found anything they're very transparent they release all their results and so far it's orders non detection there's an established international protocol if they do find something they will notify they will confirm it and they will notify the United Nations and share all the data so it won't be some sort of alien cover-up but what might it look like at that moment well in science fiction it would look something like this this is a fabulous movie contact with Jodie Foster all about the search for alien life and while it's largely based on real life Jodie Foster's characters based on a real person Jill tarter this is the moment where she detects the alien signal and we use supercomputers look for the signal but of course because Hollywood she's using a pair of headphones listening to the radio signal and the most ridiculous thing is a few second after the scene when she detects a signal she whips out her walkie-talkie and starts yelling for the controller I'm asking them what's going on these are the most sensitive radio telescopes ever built the last thing you want to do when you're looking for aliens is to use a walkie-talkie it's just complete that signal for the walkie talkie would completely drown out the signal from the aliens so this is not how we would find it but it would actually look something like this this is indeed an extraterrestrial signal this is the Voyager spacecraft which has now left the solar system and when they are setting up for each night to go alien hunting the first thing they do is to make sure that they can detect Voyager so yes if there are aliens transmitting you could see them and unfortunately except Voyager they've never seen another signal like this maybe the reason why we haven't found anything is because everyone around the galaxy is listening every alien is listening and no one is actually talking and so people have thought about this and said well maybe we should talk a bit and see if anybody else can hear us and this is called Metis messaging to extraterrestrial intelligence it's controversial some people say we shouldn't be transmitting we shouldn't be saying that aliens hey we're here and we're super primitive and we don't have warp drive yet because maybe they'll say oh that looks like a good planet to enslave but but people have transmitted messages this is one of the first examples of meki this was a signal sent from puerto rico in 1974 and because it was controversial they decided to play it safe and they beamed it to a star that's 25,000 light-years away so even if they get the message even if they respond straight away we have 50,000 years before we have to worry about it it's a very simple message it shows you sort of what the telescope looks like what humans look like there's sort of a crude diagram of DNA here and a bit of chemistry and so on it's a very basic picture here's another message this was on two space probes that were launched in the 1970s called pioneer there's an actual plaque that was bolted to the spacecraft these probes have left the solar system now but maybe one day millions of years from now some alien will find them so the equivalent of the old guy on the beach with a metal detector some alien will find this thing and go what is this and they will look at this Clark and go huh they hadn't invented clothes but so this is this is the pioneer this is the Pioneer spacecraft it's showing you how big humans are men and women relative the spacecraft but controversially and people now say maybe this was a mistake this is a chart of the galaxy showing you how to the Sun and if the aliens find the Sun that very hopefully says well they found the Sun and here we are we are the third planet so it's really a map saying come and invade us the chances of these plaques ever being found is obviously incredibly small but here is a message that's embedded on the Pioneer craft the most recent space probe to leave the solar system was New Horizons at flew past Pluto in 2015 and passed an incredibly distant asteroid Eric off in 2019 is now heading out into the darkness and to play it safe it has a few stamps it has some coins maybe their stamp collectors you know I've always won a one from the solar system it has it has a bit of writing a bit a piece of a novel which presumably aliens won't understand and it has the names of millions and millions of people who volunteered it has their names engraved onto a DVD but so we are sending out this stuff and maybe one day millions of years from now aliens will actually find it okay so I hope I've convinced you that even though we don't yet have warp drive an aliens that the present and the near future are incredibly exciting I am a little bit disappointed that we don't have our jetpacks and that we don't get to shoot horrible aliens with our laser guns but when I step back and think about it I think you know reality is still pretty amazing as a comparison to sort of take away your disappointment that this is not 2020 even though we were promised the 1970s is that this is what it would look like here is an image taken by Canadian astronomers and so I told you it's really hard to see directly planets around other stars but you can do it and this is incredible back in 1606 or something I forget the exact year Galileo looked at Jupiter through a telescope and he saw the moons of Jupiter going around Jupiter in real time he saw a little mini solar system the moons going around well we can do that now with us does he's an actual image of planets going around a real star and so this is the actual thing here from 2011 to 2016 we can actually see planets orbiting other stars and even to me that I mean if you were told me 20 years ago we could do this and say no no that science fiction what we can do it but I think perhaps to me the the thing that's that says we really are living in real life science fiction is the fact that right now there is a 900 kilogram nuclear-powered robot that has a rock vaporizing laser traveling around Mars and if we ask it to it actually takes a selfie of itself so I hope I've convinced you that in the words of JBS Haldane the universe is not only queerer than we suppose but queerer than we can suppose thank you so much you go to concave you very good thank you so much that was fantastic let's open the floor to questions so the microphone is right there you can just form a line if you have some questions all right you get going and I'm gonna look for online questions and you you win the race you're first hey there so you mentioned that we're able to isolate and detect these exoplanets through transit signals and you also mention the bio signatures that we can find off of them so what's the process from going from this one little blip that we get in transit to finding an entire bio signature from that one little blip it's really hard so when what you can do is you can take a spectrum of the star when there's nothing going on when the planets not going in front of it and then you take another spectrum of the star when the planet is going in front of them and if you take the difference between those two spectra the star goes away and you're left with the planet but you've got to remember the planner is billions of times fainter than the star so even the slightest error in the subtraction will completely wipe out the signal plus the signal is really really faint so you have to stare not just at one blip but hundreds of these blips over and over again and add them all up and slowly build up the signal and even when you do that the spectra are not very spectacular at the moment so it's really just a case of gathering up huge amounts of light from these blips you have to know exactly what time they're going to happen and you and you have to get it over and over again and it's hard because suppose the blip happens every eight hours okay so so you get one say at midnight and you go great I've got that one but the next one's at 8 a.m. the Sun's up you can't do that one the next one's at 4 p.m. you can't do that one either so I'm often the periods of the blips don't even match up to when it's nighttime and you miss out on a lot of them so it's really really hard work and it requires not just a lot of scientific understanding but incredible technical skills to get these very weak signals out of the data so far we have not detected one of these bio signatures that telescopes aren't big enough but we've demonstrated the technology there's a lot of world leaders of doing this technique right here in Canada and once we have these huge telescopes going there's a very real chance that we'll be able to do this the first detection will be really controversial to be very marginal and some people won't believe it this is the way science works but eventually they'll be one that's a little bit more convincing and some one else will reproduce it with a different telescope and men will see the same thing around a difference though and people will start to believe that we actually have detected these bio signatures take another question in the theater thank you for your talk aliens Roswell New Mexico yes no maybe I think the answer is no I think I think you've seen how difficult is to travel to other stars if you are going to travel from to Earth from a different star you know why you're gonna come all this way and then just sort of dissect a cowl or something you know you're going to do something more with it note that there used to be all these claims of aliens and strange lights in the sky you know and then by the time someone else looked it would be gone every person you know in this continent now has you know a phone that can take movies and and all the rest of it so if there were aliens making these strange visitations there'd be you know really convincing footage of it popping up on YouTube scientists with credibility would be seeing these things you know none of that has happened all of these claims disappeared since everyone's has a phone in their pocket there's just no evidence this has ever happened I'm afraid 1948 no phones thank you let me take one online which feels like a nice physics question with the ion drive eventually turned positive after emitting negatively charged particles so it's it's emitting ions which are positively charged particles but that creates electrons electrons are just electrons a much lighter and they just sort of discarded so so no so yes by emitting ions you're creating negative charge but you just discard that throw that out of the window that's a good question yeah but the amount of fuel obviously slowly shrinks so they are the the the NASA Dawn probe that I mentioned it went as I said it went through four hundred kilograms of fuel in 11 years so that's pretty good mileage it took 11 years to burn through 400 kilograms of fuels so it's incredibly fuel efficient but as I said really really slow and gentle perfect inside hello hi I'm Moony I'm also every big fan of science fiction's so my actually two short questions first one is it didn't talk about parallel universe how physics and Astro Astro physics they look at the parallel universe and the second one is it's bit funny because we have seen in in the last 50 or years there were many rumors about UFO Bermuda Triangle and all that but nowadays we don't hear anything like that what's the reason for that so I think I think the answer the second question is is that you know people can't just as I said before people can't just say I saw a light anymore you know if they saw something they would have taken a photo of it and they're just everyone has a camera and there's nothing out there it was easy to make things up when you we didn't have to prove it the answer to your first question so the question is you know what does physics have to say about parallel universes is that the question so yes so there's lots of great science fiction about parallel universes some of which are very similar to ours and some of which are very different you know it's controversial physics says that parallel universes can exist but so far we haven't found any way to actually prove that that is happening quantum mechanics which is a branch of physics that allows electronics to work one interpretation of what quantum mechanics is is that it's actually a continuous creation of of new branching universes something called the many-worlds hypothesis that's one interpretation of quantum mechanics people have been arguing about this for decades but so far we haven't had any way to prove it there are some claims that you could actually see another universe bumping into ours by the faint glow in the sky called the Cosmic Microwave Background but none of this is really borne out so it's valid physics and people have conferences and write scientific articles about parallel universes all the time but right now we don't have any way to to test that to know that they exist let alone actually you sort of look at them or jump between them let's take one more in the theater and then the remaining theater questions you can get them after and I have one online to finish up so you're up thank you very much I'm just wondering when you were talking about warp drive in different ways of traveling through through space and you mentioned things like you know if we go 20% the speed of light and then you you said if we could go 99% the speed of light you never mentioned going the speed of light so I guess I'm wondering based on what we know now it's that possible is it possible to go multiple times the speed of light and if so what would it take to do that so we the only way you can travel the speed of light is as a light beam so I did actually talk about traveling at the speed of light though I didn't actually say it explicitly and that's teleportation if you break me up into information and transmit me in a radio wave I'm essentially traveling at the speed of light and so I could travel to a star that's four light-years away in four years and then get reassembled at the other end as long as you get around these minor problems of the amount of data and transmission speeds but that is traveling at the speed of light no actual object can ever travel the speed of light that's forbidden by the laws of physics but information can travel at the speed of light indeed every time you talk on your cell phone or listen to the radio you are receiving information that has traveled to you at the speed of light the question other question you asked is can we travel faster than the speed of light and the answer yeah the short answer that is no like that the laws of physics forbid anything from traveling faster than the speed of light if you use warp drive then maybe you could drag space at faster than the speed of light in at least that's what happens in Star Wars and Star Trek that's not actually moving at all it's just dragging space so maybe that would be a way to effectively move faster than the speed of light all sorts of paradoxes happen if you can do this you could actually travel back in time and then you know the usual story of you or you could kill your grandfather but if your grandfather's dead then would you be born how could you do that so I think the short answer is is that all sorts of inconsistencies come up if you could work out a way to travel faster than the speed of light and might there might be clever exceptions to that rule but as far as we know the fastest you can travel is exactly the speed of light thank you and let's take one last online question what was your favorite sci-fi movie as a kid [Music] that's a great question III know I can answer the movie of what my favorites are for me as an adult but as a kid look it's hard to go past the original Star Wars movie I actually saw it at the drive-in so I know that makes me probably pretty old but but uh you know seeing that movie I mean the special effects of Star Wars were like nothing we had ever seen at the time the story was amazing the special effects the baddies were the perfect villains and the good guys are the perfect good guys like like a lot of other people grew up in the 70s you know Star Wars has completely shaped my thinking like I wanted Star Wars and you know every research paper I write hopefully is one more step towards making that happen that sounds great ladies and gentlemen dr. Brian [Applause] [Music]

Channel: Perimeter Institute for Theoretical Physics

Views: 982,967

Rating: 4.4536471 out of 5

Keywords: physics, theoretical, canada, ontario, science, STEM, Perimeter Institute, aliens, warp drive, astronomy, astrophysics, space, Dunlap Institute, University of Toronto, Bryan Gaensler, Canada Research Chair

Id: fzweIEvN8sc

Length: 81min 13sec (4873 seconds)

Published: Thu Feb 06 2020

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In his live public lecture at Perimeter Institute on February 5, 2020, astronomer Bryan Gaensler (Dunlap Institute for Astronomy and Astrophysics, University of Toronto) explored the latest thinking on interstellar travel and on the search for alien life – including why he believes the frontiers of current research may be more exciting and visionary than any fictional stories we can imagine.

Perimeter Institute (charitable registration number 88981 4323 RR0001) is the world’s largest independent research hub devoted to theoretical physics, created to foster breakthroughs in the fundamental understanding of our universe, from the smallest particles to the entire cosmos. The Perimeter Institute Public Lecture Series is made possible in part by the support of donors like you.