The God Particle with Brian Greene (full session)

it's a pleasure to be here with you this afternoon in the early hours of July 4th next Wednesday here in Aspen there's going to be a press conference taking place in Geneva Switzerland at CERN the particle collider in Geneva where scientists are going to update the world on the search for the long-sought Higgs particle this follows a previous announcement that you may recall back in December where the scientists gave preliminary evidence that this elusive Higgs particle had been found and around the world right now there are physicists who are eagerly anticipating that on Wednesday that earlier preliminary result will turn into a definitive result and we will have found the so-called god particle or in the modak words of Linda Resnick to quote from an email that Linda sent me last week physicists have finally found God in little tiny particles now I should say at the outset that while the media loves this term this name the god particle since there's no connection to God or religion we physicists don't really like this name at all the term itself actually comes from Nobel laureate Leon Lederman who says that the actual nickname that he coined for this cagey elusive particle was the goddamn particle but he was writing a popular book on the subject at the time and the publishers convinced him that this wasn't the best title for the book so he was willing to accept this shortened form about putting names and nicknames to the side we may be on the verge of an historic discovery so what I want to do in the brief time that I have here is tell you a little bit about what's going on and I'll do it in three parts in part one I'll tell you about what the Higgs particle is and how we've been looking for it in part two I'll describe why this particle is so important to us physicists and finally in part three I'll describe why you should care now you'll note I put the why you should care part at the end because in the off chance that I don't convince you that you should care the talk will basically be over anyway ok part 1 what is the Higgs product will this story this part of the story begins with a seemingly simple sounding question which is where does the mass of elementary particles electrons and quarks Waiters their mass come from right I mean we look around the world and all objects have mass which you can think of as the resistance which those objects offer to having their speed increased or decreased right so for example imagine I have in my hand a baseball or a shotput right and I want to speed it up and as I try to throw it it offers resistance I feel that resistance in my hand in my arm and my muscles in that resistance is the mass of that object similarly if I had an elementary particle like an electron or quark if I tried to push on it it also would offer some resistance that would be its mass but the question is where does this resistance come from where does the mass of the particles come from now one answer that you could put for it is elementary particles have mass because they do you can just say this is an intrinsic part of the way the universe is put together period end of story now look you can take that approach but physicists don't find that kind of an answer satisfying we don't like just so stories you want to find a mechanism by which particles acquire the mass which experiments reveal them to have and in the 1960s a group of physicists working independently largely from one another came up with just such a mechanism which over the decades has been most closely associated with the English physicist Peter Higgs and what I like to do is tell you about this Higgs mechanism for giving articles there's mass here's the idea here's Higgs idea who's Eric goes Higgs imagines that all of space is uniformly filled suffused with an invisible substance an invisible substance sort of like an invisible molasses that permeates every nook and cranny of space and the idea is that as a particle like an electron tries to move through this molasses when you try to speed it up its interaction with the molasses the resistance that it feels as it tries to burrow through the molasses that's what we interpret as the mass of the particle and in fact the idea is that different particles would have a different degree of stickiness which means they've experienced a different amount of resistance as they try to burrow through this pervasive molasses which would mean that these particles would all have different masses which is just what the experiments show so that's the basic idea according to this Higgs proposal of how the elementary particles would acquire the mass that they do now to be sure this is a strange peculiar sounding idea among other things it would rewrite the very meaning of nothingness of empty space because it says that if you were to vacuum a region of space removing all of the matter down to the very last atom it wouldn't be completely empty at least not in the conventional sense there'd still be this pervasive Higgs field this Higgs molasses which you can think of therefore as a kind of essentially unremovable occupant of space now that may ring a bell for those of you who have studied anything about the history of science there's a long discredited idea that sounds kind of similar right the ether right sounds sort of like the ether so scientists were not at first willing to jump on board this strange idea in fact the first paper that Higgs wrote on the subject it was rejected by the journal to which he submitted it but over time Higgs was able to convince the community of physicists largely based upon theoretical considerations based in the math and I'm going to briefly summarize for you in just a little moment he was able to convince physicists that this was the best explanation that we had for giving the particles the masses that they have so much so that when I began graduate school in the mid 1980s people spoke about this Higgs idea with such confidence such nonchalance that for many months I had no idea that it was hypothetical but it was hypothetical back then and it is still hypothetical today but that may all change on Wednesday as this idea may migrate to the arena of confirmed scientific fact now how would that happen how are we looking for this invisible Higgs feel this molasses that is meant to permeate all of space here's the idea there's this big accelerator in Geneva the Large Hadron Collider about 18 miles around and what happens in that Collider is that protons are sent cycling around the collider in opposite directions near the speed of light so fast that they can traverse at 18 mile racetrack more than 11,000 times each second and these particles engage in head-on collisions now the math suggests the idea is that if the Higgs proposal is right then when the particles collide the energy of that collision can kind of jostle this Higgs ocean jiggle it kind of slick off a little droplet of the Higgs ocean and that little droplet would be what we call a Higgs particle now the scientists would not actually see the Higgs particle itself because the mathematics shows that these particles are highly unstable they quickly fall apart they decay into more familiar particle photons electrons and neutrinos but the idea is that by playing a kind of CSI game looking at the particles that are produced scientists can reconstruct the process that gave rise to them and in that way be able to pinpoint that there was Higgs particle there that's the idea that they are pursuing now framing it that way it sounds maybe kind of straightforward but this is a monumental challenge to carry out this procedure these protons are slamming together more than half a billion times each second so to try to find this delicate little signature of this little Higgs particle falling apart against this chaotic maelstrom of other particle processes that are taking place well that's like trying to hear a tiny delicate whisper over the thundering deafening din of a NASCAR race terribly difficult to do but over the decades physicists have developed techniques technology they've built these enormous mammoth detectors that surround the collision point and can capture all of the particle detritus the relentless splash of particles that are being sent out every second take that data feed it in to some of the most powerful computers that exist which are running millions of lines of dedicated computer code in an effort to show that this Higgs idea this Higgs particle is real and this may result in a definitive discovery that we'll be looking for next Wednesday now that's what the Higgs field Higgs particle idea is all about how we're looking for it why do we physicists really care about this or frame differently why have we convinced governments around the world to spend 10 billion dollars to build the Large Hadron Collider to look for this particle or framed another way still is this Higgs idea really progress or have we simply substituted for the earlier question why do particles have mass the new question why is there a Higgs field in a Higgs particle well it is real progress it takes a little bit of background to understand why so let me quickly describe it for you back in the 1960s when scientists were examining the output of the then most powerful particle colliders they found that the blindingly chaotic and complex data that was emerging could only be understood using one key idea and that key idea is the idea of symmetry symmetry is an idea that we are of course all familiar with it's a kind of pattern that exists between seemingly distinct entities but when you realize the pattern you see that they're part of a more complete and unified whole that's easier to describe I mean write me take my face right cut it in half this side is the mirror image of this side more or less you put it together it's a more unified whole take a take a snowflake write a snowflake has five distinct points but you can rotate the snowflake taking one point into another realizing that they are all part of a more unified whole or take a take a sphere a nice silver sphere it's got many different points on the surface but by rotating the sphere you can take one point into any other point and in that way you see that they are all part of a more unified whole which makes it easier to describe that object similarly the scientists found that when they were examining the data from the particle colliders they found that the data itself fell into interesting patterns symmetric patterns that guided them to equation simple elegant equations that could describe what was going on but the problem is this when they study those equations in detail they found that if particles had mass the symmetry between the equations would be spoiled they no longer work they'd fall apart so a great tension between these beautiful equations on the one hand and the need to give particles of mass on the other what Higgs showed is that you could have your cake and eat it too and by that amines if the mass of a particle comes from its interaction with an environmental influence this Higgs ocean that surrounds us then you can show that the equations can preserve their elegant symmetry and the particles can get their mass from this environmental effect and with that the standard model of particle physics was found the standard model of particle physics is a simple little equation it can fit on a t-shirt a simple equation that's able to describe all of the data come from particle accelerators around the world and by fitting on a t-shirt I literally mean it can fit on a t-shirt Alec and Sofia come up here one second so here on this t-shirt is the standard model of particle physics okay the first term here it describes the nuclear and electromagnetic forces these are the particles of matter and this guy over here this symbol Sophia what is that symbol meant to describe a Higgs field yes thank you very much and this term over here what is that man I hate pretentious I hates potential thank you very much you guys head off over there and with that simple equation we've been able to describe data with fantastic accuracy and every feature of that equation has so far been experimentally confirmed except for the Higgs part of it and that's what we're waiting to have happen on Wednesday now that's one key reason why we are excited by this but in the last few minutes let me describe one more key feature as well that Higgs particle is not just another particle in a long list of existing particles it has fundamentally different characteristics you see we have learned that every particle in the world electrons quarks muons the trees all of the particles in the world spin around sort of like a top not exactly but quantum mechanically it's not a bad way of thinking about it and they all spin at a particular rate dictated by the identity of the particle so electrons and neutrinos and quarks they all spin at a rate that we call spin 1/2 photons and other force carrying particles they spin at a rate twice as big that we call one the Higgs would be the first particle of matter that has spin zero the first fundamental spinless particle a new kind of matter and the reason why that's exciting for us over the past thirty years we have used the flexibility of those kinds of particles the particles that don't spin to put forward theories for a whole range of ideas cosmological ideas for instance being primary among them because one of the issues in the big bang theory of cosmology is that the Big Bang says that way back in the beginning the universe went underwent this rapid expansion right we all have heard about this idea but the Big Bang mathematics leaves out something pretty important which is the bang itself a doesn't tell us what would have driven the outward expansion of space in the first place remarkably that kind of object that kind of Haig's like object that kind of spinless object if you have enough of it in a little tiny region of space you can show that would yield the kind of repulsive gravitational push that would indeed drive everything apart would indeed put a bang in the big bang that's a speculative idea I wouldn't want to have it married to the announcement on Wednesday because Wednesday if in fact this particle is found that's bonafide science but over the course of 30 years we've made use of that kind of a field so profoundly that if indeed it is confirmed that it exists we will have at least some circumstantial evidence that many of the ideas that we have developed over decades that they are heading in the right direction so let me finish by turning to my third part why you should care you don't necessarily have to care right I mean maybe everything that I've said so far just so fires you up that you already care that that would be nice but there's some people who just don't really care about these abstract theoretical ideas right i friends of that sort you know i've relative min you know frankly my mother is like that right i mean she still wishes that i was a doctor i tell her well i am a doctor she says not that kind of doctor you know this whole thing that just keeps on going so she needs and many others to something more tangible and i think a good way of thinking about a more tangible impact of this kind of detailed discovery and trying to understand the nature of the universe comes to us from an analogous historical discovery back in the 1920s and 1930s when the subject of quantum mechanics was discovered and experimentally confirmed now back then it could have felt that quantum mechanics was equally abstract and theoretical compared to the things that i'm talking about here today but over the course of 80 years a theory that began life by helping to understand molecules and atoms and subatomic particles that's what quantum mechanics is about has been parlayed has been harnessed by science and technology to yield all manner of spectacular technological wonders right anything that has an integrated circuit relies upon quantum physics it was quantum physics that allowed us to be able to manipulate electrons through tiny little wires giving rise to personal computers cell phones medical technology that saves lives around the world all the time which is just to say the fundamental discovery can have a profound impact on the way that we live our lives you just have to wait for theoretical discoveries to turn into practical applications and the history of science shows that that is the pattern that typically happens let me finish by giving you one final thought maybe a more personal thought on why these ideas about the Higgs are so important so exciting back when I was in high school and I was taking my first physics class the teachers set us a problem of a piece of chewing gum attached to a baseball on the ball was swinging in our challenge was to figure out the motion of this ball as the chewing gum stretched and it swung back and forth like a pendulum I sat at my desk it's not actually a hard problem to do anybody who takes a good course in physics one can do it I solved the problem and I ran down the hall to my dad to show him not because he cared about baseballs and chewing gum but because of this idea that mathematics a calculation that you do at your desk could describe something in the real world with such an amazing idea that mathematics can transcend so much of the world around us I mean today you've already heard interesting important conversations about politics about economics conversations that affect millions billions of people around the world but I tell you all of it is transitory doesn't mean it's not important but it's transitory 100 years from now will be another set of problems economic ones environmental ones political ones and of course we need to deal with them that's how we build the fabric of everyday life but how exciting is it to sit at your desk and do a calculation that goes beyond everything that's transitory calculations that might reveal fundamental features not about what happens here on earth but about the entire universe the entire universe it's hard for me to imagine anything more thrilling than that thank you very much

Channel: The Aspen Institute

Views: 135,448

Keywords: AIF12, aif12_greene, Higgs Boson (Idea), The God Particle: If The Universe Is The Answer What Is The Question? (Book), The God Particle, Physics (Idea), Physicist (Job Title), Science (Literary Genre), Higgs particle, Brian Greene (Author), Aspen Institute (Organization), CERN (Organization), mass, Peter Higgs (Academic), Particle Physics (Field Of Study), Aspen Ideas Festival, atoms, matter, space, Scientist (Job Title), Large Hadron Collider (Exhibition Subject), protons, aif12_128

Id: d4RSbSLt24I

Length: 22min 8sec (1328 seconds)

Published: Mon Jul 02 2012