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Physicist Archana Sharma and astrophysicist Geraint Lewis explore the mysteries of the universe, the Higgs boson, and modern physics in conversation with Marcus du Sautoy, presented by Vedanta.


#GodParticle #HiggsBoson #ScienceExplained #Cosmology #Astrophysics #ParticlePhysics #MarcusDuSautoy #ArchanaSharma #GeraintLewis #BigIdeas

~HT.178~
Transcript
00:00and so exciting to see so many of you here i did wonder whether you'd all come to see the person
00:09that was uh introduced falsely but um uh hopefully you're all here i mean we actually got turned
00:15away at the door so there's no more room i said well i think you might want us three in here so
00:20um uh fortunately they did let us in but um you know i think it's a real testament actually to
00:24the jaipur literary festival um that you know i've been coming to the festival for many years
00:29uh to invite scientists along because you might think well what are scientists doing at a literary
00:35festival you know isn't this just about poetry and novels and things like that but i think the jaipur
00:40literary festival realized very early on that scientists have amazing stories to tell stories
00:47that tell us about where we've come from where we're going to go next some of the stories that
00:51people will start exploring um in our panel so and i think the fact that uh they've been so
00:57successful in in promoting these scientific stories is testament to how many of you are here today and
01:03and i can see some young people here as well and for me that's important these stories for me are
01:08what made me into a scientist somebody telling me stories so i thought we'd just start with our two
01:14panelists uh just saying well what was it that brought you um to choose to do science as opposed
01:20to becoming a novelist or or something else extraordinary so why why did you become a
01:25scientist exactly like you said there was a scientist from newcastle upon time who came to
01:33my university to give a lecture on volcanoes and the wonderful colors of the lava and the kind of
01:41display he had told me that this is exactly what i want to do i want to look forward to studying
01:48something in deep to go into the depths and the profound uh understanding of why the universe is
01:56what it is and why does it matter so um somebody telling you stories exactly absolutely absolutely
02:03it's the indeed the fire and for you garaj what was uh inspiration um inspiration was i guess just
02:10looking at the natural world and eventually thinking to myself well how does this stuff work and i guess
02:16at some point i came to realize that we do have a mechanism whereby we try to put together the rules
02:22of the universe and how everything behaves and i i never actually thought i would be a scientist but i
02:28was always kind of interested in this idea that we can work out the underlying rules and from that
02:34you know where did we come from and where are we going so again just trying to understand the
02:39universe around us and so you've both chosen rather different ends of the scientific spectrum
02:45the incredibly small particle physics to the very big astrophysics um so what drew you to the both
02:52those ends of the spectrum i think uh if i can bring the analogy of a large onion and if we were to keep
03:01peeling and peeling and peeling and keep going inside the onion in the end you would still have a cell
03:07that you can subdivide and keep going inside it's exactly the same way the universe functions you know
03:14we have no idea of how the universe worked before and before we understood some kind of theories that
03:22came along the way and of course there have been so many scientists who have been contributing
03:26to the theory of the universe and to understanding the secrets of the building blocks of matter
03:32so the onion still is not completely uh at this fun most fundamental uh point because when the greeks
03:42called the atoms an atom it meant indivisible and now we know we all know very well that the atom can
03:48be divided and there are electrons and protons and neutrons and quarks and who knows what's next
03:54well exactly who knows what's else i mean if you look back in history i think every generation
03:59thought that they'd hit the last layer of that onion and i i think we still believe that you know
04:05now we're back down to electrons quarks neutrinos and we feel like that's the building blocks but
04:11you know there is the hint you know are these things strings maybe that make up these particles
04:16i mean that's one of the challenges of science will we ever know that we've reached uh the kind of uh
04:22the answer that explains it all well if i can bring in a quote here which is rather uh known i
04:29think to the audience here in 1945 the chairperson of ibm said the world needs about five computers
04:40so today we do not know what we do not know so we need to remain humble i think that's what big
04:47science teaches us where we work together in collaborations with thousands and thousands of
04:52people from all over the globe and we come together to do these experiments and we need to remain
04:58humble to the fact that definitely we know a very tiny fraction of what can be known and you're right
05:06you went you went i think you did do some work at cern originally about the very small um as a
05:13student but but you chose a very large so what was the what flipped you to to add layers to the onion
05:20i guess i i guess when i found out about science i was drawn into physics because i thought what are
05:26the fundamental bits of the universe and it seemed to me that the interesting places were the very very
05:31small or the very very large and um it really was a toss of a coin about which path i was going to
05:38take at the end of the day but um working in the large scale universe and asking those big big
05:44questions about where did this universe come from and what you know was there anything before that's
05:49what drew me away from the very very small into the very large but they are connected it's not like
05:55that we're two separate fields there's a lot of cross talk between us yes i guess um issues of um dark
06:02matter uh is a kind of cosmological question was discovered because we realized there's something
06:08pulling the universe in ways that we don't understand yet i guess that's the question
06:11about well what are those particles that make up dark matter so is that the sort of connection
06:16between the two absolutely um i i have a small label that i put on myself which is astro particle
06:23physicist and so there's a there's a trying to have it all yeah so there's a a large number a
06:30growing number of particle physicists who are turning towards the sky there's so much you can do at the
06:36large hadron collider and you need to put in more and more energy to get more and more interesting
06:40results out but the universe already does things that incredible energies and so people are saying
06:45can i take what i've learned already and apply that to some of the things that we see on the sky
06:50so astro particle physics tries to essentially really bridge that gap and answer those questions
06:56they said what is dark matter we know that there's more stuff out there which is not made of atoms like
07:01this by a factor of six or seven and we have no idea what it is but it dominates the universe so
07:09again it's those kind of questions that you know keep us in you know we brings us to work in the
07:13morning and so what would you say were the essential differences between the way that you do science i
07:20mean particle physics you know you've got these big experiments going on at cern but with the universe how
07:26how do you do experiments i mean is it just a very passive as opposed to an active engagement as a
07:32scientist yeah so in astronomy we're mostly observers right it would be nice if we could
07:37manipulate the universe but it's a lot bigger than that and and so yeah we we observe and what we try
07:44and do is we try and collect information across all radiation bands from from gamma rays down to
07:49radio waves and also from particles that collide with the earth we try and collect those as well
07:54and from there infer what's going on in the universe so we are presented with one universe we're trying
08:00to work out what is going on with that universe but as you said we cannot manipulate it well china you
08:06do a lot of manipulation at cern well well uh i mean so this is the accelerator that we have in nature
08:13where you have particles coming from the outside world and we are trying to understand that only from
08:18the earth about the cosmos what we are trying to do is to recreate the conditions of how the universe
08:26was created so obviously we are not going to create the universe itself right we are going to do that
08:33albeit on a very very very minuscule scale in safe conditions underground and we will study how the universe
08:41was born and the kind of particles that he mentioned like the dark matter particles as we all know that
08:48we just know barely five percent of the whole universe is made out of matter particles like
08:55of which me you and the table is made of so dark matter particles could be created when we are recreating
09:03this big bang under the uh in our uh laboratory conditions so the the big difference here is that
09:10we need data because we might be able we just might be able to have a candidate particle of dark matter
09:18created and then we need and that possibility is like finding one gold grain of sand on all the beaches
09:26around you know where you have ever been so what do we need we need data to actually
09:32uh siphon out or sift through whittle down to that dark matter particle but i guess data is also an
09:40issue um when we go to astrophysics i mean we have a project in oxford called galaxy zoo because basically
09:46there were so many images of galaxies coming in that there weren't enough uh scientists to actually look
09:51at these so we asked the public to help us identify spiral galaxies um and they even identified a new
09:58sort of galaxy the the green pea galaxy which all the scientists were saying oh just ignore
10:02that as an anomaly and um so i mean data and i guess we're going into a period of a lot of data
10:08coming from the the new telescopes that we're sort of using to look at the sky um yeah absolutely i
10:14mean the secret is that we're terrified by the amount of data we're going to collect so you if you
10:19see me wandering around i've got a blue bag with skao written on it which is the square kilometer array
10:23observatory which is a telescope being built across south africa and australia and in fact each telescope is
10:30going to have to essentially have a supercomputer attached to it to work out how much data we can
10:35throw away because we can only keep a little bit of the data that flows so we are facing this absolute
10:41avalanche of data and we're trying to have to sift it before we can even work with it so yeah data is
10:46the name of the game at the moment um i one of the big themes of course which is running through this
10:51festival and many festivals is artificial intelligence i mean i've got two events that i'm doing over the next
10:56two days on on the subject but i guess this is a place where um artificial intelligence which is
11:01very good at spotting patterns in data significant messages um might be a very useful tool for both of
11:08you uh yes absolutely i mean we've in in astronomy we've faced this data problem for a while and so
11:15we were using the precursors to artificial intelligence before it really was called artificial intelligence which
11:21is humans no no neural networks and large data and all that kind of stuff and it's all morphed
11:27into this entire picture of ai but yeah we we need that to work with these data sets it's all
11:33multi-dimensional and we're looking for things in there for a human being it would take a lifetime
11:38maybe to find one thing but of course we can get machines to churn through these this data a lot more
11:44efficiently indeed it's the same thing for us however on another scale because our collisions
11:50that happen on the collider are 40 million times a second so we are collecting i think the largest data
11:57set on the planet has been collected we crossed one exabyte of data i mean how many zeros are there i
12:03think the younger ones here might know but it is quite a challenge and we also need to have triggers
12:10and algorithms while taking the data so that within the 25 nanoseconds when we are making decisions
12:18that's how the artificial intelligence and pattern recognition actually evolved i must say because
12:24that is a precursor to what ai has become today we've been doing research for the last 25 years with data
12:33data governance pattern recognition like you already said and in fact the world wide web i think tim
12:39sir tim berners lee was here and that was also some way looking forward how to deal with data and
12:47today we can't imagine the world without the world wide web and in fact we do not know the kind of
12:54things that are coming out from our experiments that will then reach to the society and in your pockets
12:59at some point where you will say oh i could was there a world without the world wide web
13:04now uh this session is called the god particle which might be what drew so many people into the
13:11room i'm not sure um uh which is about uh you know probably the one of the biggest discoveries that was
13:17made um in the last uh 20 years uh 30 years uh so we should probably address um what this particle is i
13:25think actually it should have been called the god damn particle because uh the person who was trying
13:30to write a book about it was saying it's so elusive we can't find it and then the publisher crossed off the
13:35damn and it got left as the god particle so i think many scientists really resent this uh
13:40term and want nothing to do with with god or does it i mean um it's interesting so i'm going to give you a
13:46little challenge which is one that um william watergrave our science minister who was working under
13:51uh margaret thatcher at the time and he this was before we we were knew this thing might exist but
13:58it hadn't been discovered and a lot of people were asking for money from the government uh to fund uh
14:04the you know what's happening at cern um so the science minister william watergrave offered a challenge
14:09which is um how to a lay person do you explain what the higgs boson is um so this is an interesting
14:18challenge you know sort of really kicked off a lot of scientists trying to engage with the public
14:22about um what this thing is so um what's your dinner party kind of take on how you tell your neighbor
14:30who says oh i know nothing about physics all right all right so first of all thank you all for coming
14:37here and imagine that we are at a party right and we are having a good conversation with each other
14:45you're not really listening to me but you're talking to each other and freely moving around
14:49right maybe on all the grounds that are here and and you've got many of your friends nobody's stopping
14:55you from moving from one place to the other but then suddenly there's a rumor of a big star who's
15:01going to arrive here it's already happening at the speaker lounge by the way so who could be that big
15:08star of today in india ranveer singh sharuk khan okay sharuk khan everybody knows sharuk khan so imagine
15:18that you have not seen him but there's a rumor that sharuk khan is coming here and what would happen at
15:25that moment of time just think about it there are several gates of entry into this venue and you might
15:32want to scratch scratch your head saying which gate would he be coming from and i would start migrating
15:38there depending on my fan quotient of how much i like sharuk khan because there could be people who
15:44say oh sharuk so what you know but then there would be people sharuk you know they will push people and
15:50they will go to that gate number three or whatever it's announced that he's coming from so these people
15:57they become suddenly heavier do they they become heavier because they are trying to move and push people
16:04and they are not able to move while there are other people who are relaxed and not really interacting
16:09with this information about sharuk khan coming here and that is the moment when all the particles that are
16:18all of you at that moment of the big bang actually acquired mass higgs is like a star and i might remind
16:28all of you that half of the universe has the name boson allocated because of satyendrinath bos who gave
16:38it who worked with einstein and so we thank you the whole universe half of the world half of the universe
16:48is bosons the other half is fermions and the higgs boson indeed is the star like sharuk khan who appeared at the
16:58moment when all particles were moving around freely and when they started interacting with the higgs boson
17:06or the higgs field i would say they acquired mass so i say that the universe had possibilities had energy
17:15but it mattered only when the higgs boson appears i thought that was very good let's give a round of
17:22applause for um yeah makes sense now you're you're both actually fantastic scientists but also fantastic
17:33communicators as well i mean you're right what's the sort of challenge for you of uh trying to explain
17:39uh some of the difficult concepts um to the public i mean do you have sort of uh ways that you do it
17:45which kind of bring uh some of these very difficult concepts alive um yeah there are many challenges
17:51because of course i myself and the china we work in a world of mathematics and science speak and i want
17:59to get across concepts to you like how the universe is expanding what does expanding universe mean etc etc
18:05and we have to work out how we can turn mathematics into pictures that can get the ideas across
18:10and it's a bit of an art form because a bad analogy tells you nothing really so it's like as we were
18:18just talking about the the higgs boson there you you have to think about the picture that you're going
18:23to use and relate that to the concept and it's not always easy especially when you get into the the really
18:30complicated aspects of of cosmology or particle physics so it takes a lot of thought and and appreciating
18:36your audience and thinking about how you can relate those concepts to what picture they might see
18:43so the higgs boson was probably one of the biggest discoveries in particle physics what would you
18:47nominate as the big discovery that's happened in the first quarter century um in astrophysics well
18:53there's a few to choose from but i think it has to be gravitational waves yeah so that these are now
18:58we just they were predicted in 1916 by einstein they were discovered in 2016 so only it took a century
19:05worth of work till we could discover them but they opened an absolutely new window on the universe
19:10right so most of the information we get about the universe we get from radiation from light and x-rays
19:17and gamma rays etc but there are lots of things that go on in the dark which don't emit light so we do not
19:23know what's going on gravitational waves which are formed when you basically have a really violent event
19:30that shake space and time so hard that it causes ripples that travel across the universe we can now
19:36pick up those signals so the first gravitational waves that we detected we realized was two immense black
19:44holes like each was more than 10 times the mass of the sun colliding together and they are violent
19:50events they shake space and time we can now detect these over billions and billions of light years so a
19:56completely new window on the universe and and in the 10 years since uh we started observing them
20:03we've already revealed that the the dark side that the darker side the stuff that we cannot see
20:07there's an awful lot going on that we don't understand so yeah a new window on the universe is
20:12always good and was that due to a new sort of telescope as i understand that was able to pick up
20:18the kind of uh the you know the fine detail of a gravitational wave it it all comes down to sensitivity
20:24so so essentially what what you're trying to detect is space and time rippling and space and time ripple
20:30but in very very tiny amounts and the question is how do you detect that you you don't feel it with
20:36your body as a gravitational wave comes through you so you need to take something that you can measure
20:42precisely and see if that sort of measurement changes by a tiny bit as the wave comes through and
20:49it came down to technology the the ligo telescope the laser interferometry gravitational observatory
20:56two arms both four kilometers long a vacuum and you're bouncing light back and forth so this is a
21:03four kilometer length separation and the sensitivity got to the point you could measure a thousandth
21:09the width of a proton which is a subatomic particle and it was once we could get to those sensitivities
21:16then we entered the realm where we could detect these gravitational waves but said it took a hundred
21:21years of basically experimental advances and pushing noise down further and further before we could do
21:28that um i i don't want to big up my subject too much but mathematics of course is key to both of these
21:34predictions i mean we sort of knew the higgs boson was going to be there before we observed it we
21:39predicted the gravitational waves and and often that does come from mathematics so do you think
21:44mathematics is you know a fundamental language for everything that you do and the answer is yes
21:52the answer is yes yeah so um this is a complete side story so so one of the things that happens
21:59when you're a cosmology professor is that out there in the general populace there are often retired
22:05engineers who have ideas about how the universe works and they send you their ideas and they say to you
22:12oh this is my idea all i've got to do is work through the maths and i think i will revolutionize
22:17cosmology and you have to write back to them and say no no the you need the maths the maths is the
22:24physics the story around it is is the story but it's all written in the language of mathematics so for for
22:31all of cosmology you know start in the morning it's equations and working with maths i'll give you a
22:37money later i don't worry and for you as well i guess you know all the predictions of so many
22:43particles uh came well first of all from seeing these things but then it sort of implied there
22:48should be others as well thank you it goes hand in hand to be honest because it is a prediction that
22:54comes from theory all of you have heard about antimatter and if not then you can imagine that when the
23:00world was the universe was created then matter and antimatter should have been equal because the one
23:06equation the mathematical equation that everybody knows is e is equal to mc squared right so it should
23:13be an m plus and an m minus right and this was predicted mathematically by paul dirac and then the
23:20antimatter was observed in nature but everyone thought he was uh just ridiculous okay so there's
23:26there's a kind of negative solution but that's just maths and he said no i think this might exist i know
23:32and that's why it's extremely important from the very basic uh classroom in the high schools and
23:37you know secondary schools and colleges to be very strong in mathematics relating it with real life you
23:44know because if we do not then we study these very abstract equations and we don't even understand we
23:50keep saying are we going to ever use them believe me that's what i said and then when i i remember years
23:58later when i started my particle physics journey at cern i went back to bits pilani this is a place
24:04in rajasthan you know and there is a museum and you will see that there's a bucket of rajasthan sand
24:12with a hole on the bottom and you can go there and you know just push it and leave it so it'll create
24:18some kind of figures on the on the floor which are called lisageux figures that i learned in college
24:25but never knew how they can be used and now cathedrals and temples and all the designs that
24:32you see on top now all you see are lisageux figures over there once you know it you can't unsee it you
24:37know so i believe that mathematics is extremely important and teaching mathematics from a very young age
24:45linking it with the universe is extremely important very good yes absolutely
24:53but i guess one of the criticisms that comes you know to fundamental scientists as well is
24:57you know okay it's all very exciting to have these big stories of where we come from where we're going
25:02to go next um but how is it useful for me as you know a person on the street so um is the physics that
25:09you're doing at all useful is that does that matter you want to go first today not really that useful
25:19although i i trained phd students and they they studied the universe but not all of them become
25:24professors but they're mathematically trained they trained in computers and they go off into consulting
25:29and banking etc so we are trained in an educated uh uh society um i think this is one of the important
25:37things about blue sky science is that we cannot predict what the outcomes are going to be and
25:42the example that i i really like is that at the end of the 19th century and into the 20th century
25:47physicists were wondering what matter is made of and as they peeled matter apart they realized that
25:53atoms are composed of smaller particles and inside the nucleus there are protons and neutrons and
25:58at the time i'm sure people said well that's interesting but what's the point
26:01but one of the most advanced machines for tackling cancer these days is proton beam therapy and the
26:07people that the people that basically discovered the proton they weren't motivated by finding the
26:13cancer therapy right but the the outcome at the end of the day is that we have new therapies that are
26:19being used around the world excellent yeah thank you so proton therapy actually has been pioneered by
26:26cern also and if i can just bring it forward and hadron therapy also is very much a big need in india
26:33you know now but coming to your question about why should we care why should the lay person care that we
26:39fund so much money so much as if into a big science you know first of all the cost of not investing
26:48is huge we are building capacity we are building capacity for banks 90 percent of people who do data
26:57analysis on physics experiments they go to do risk analysis in the financial world the banks are sitting
27:05there to hoover them up you know uh in addition i would say that uh all of us have been struck by
27:13covid which came like a bolt from the blue we had no idea what it is and every one of us had a personal
27:21experience of the world coming to a halt imagine no www imagine no therapies no drug discoveries
27:31imagine no microscopes or the scanning electron microscopes with which we could see the virus for
27:37the first time and all this is coming from the humble physicist physicist laboratory so when we are
27:45doing the science we are not putting you know the the equations in the drawer they are coming to you
27:52directly or indirectly the moment we are hit by a crisis and this is of course special because the the first
28:01let's say drugs that were uh and the vaccine that was made there was a folding technique that was uh that
28:08used the web very intensely and that was also pioneered by cern and given to the world for free
28:15now if you look at um for example if you go to the hospital x-rays where do they come from everyone
28:23remembers mary curie right she gave her life and her her grave is still radioactive so these
28:31things they they look very esoteric when we talk about it but when we go through the securities in
28:37the airports or go to the hospitals as i was mentioning mri techniques the magnets that you
28:42are that we are using today to there is a market of 3.8 billion super dollars of for superconducting
28:50magnets that have been a spin-off from cern to make the large hadron collider so i can go on and
28:56on but i guess i think it's important in a way i think it's important you do because uh you know i
29:02think one of the tragedies of course is governments are very short term in their planning and thinking
29:09and they they don't understand these unexpected consequences come out of funding science for its
29:14own sake and then you get these incredible spin-offs so i think it's very important that we celebrate
29:19these stories of uh you know just pursuit of pure knowledge giving rise to amazing discoveries that
29:25impact us all can i check in another anecdote yeah go for it so there's a there's a famous
29:30anecdote that michael faraday was working in his laboratory one day and he was showing off
29:35effectively the first electric motor to a minister and explaining about what electricity was right and
29:40the motors going around and the minister said to him you know this is all very interesting faraday but
29:45what's the point and faraday's response apparently was probably never happened one day you may tax it
29:52right so this is this is okay okay can you imagine the modern world without electricity and electric
30:01motors right i mean they are everywhere but they came from michael faraday trying to work out how this
30:08stuff works now we've been celebrating a lot about uh discoveries of the past um but i wonder whether
30:15we have something called the standard model of particle physics the standard model of cosmology
30:21which all of the experiments are kind of confirming um but i wonder what has physics got stuck in
30:28in a new story i mean do we just kind of know what's happening and are there any big stories waiting
30:34out there to completely change the way we're going to see the universe or are we just going to keep on
30:39confirming that the the models that we've got are the correct ones okay so uh again picking up from you
30:48the electron when the electron was discovered and then electronics and semiconductors and everything
30:54came along uh in your pockets uh how much how much did we have to study to get there how much research was
31:03needed to get there every discovery today is a calibration for tomorrow so if we have discovered the higgs boson
31:11it needs to be studied in the greatest detail it needs to be understood on how it interacts with
31:18other particles how does it behave and are there other bosons like that and there is a lot of still open
31:26questions on the standard model which we do not understand as yet like we said about antimatter we spoke about
31:33dark matter dark energy and of course the model the theory of everything for example which encompasses
31:40all the forces of nature into one equation i'm sure you have seen many physicists wearing t-shirts of
31:46the lagrangian of the standard model but you know it is a tweaked equation if you know what i mean you know
31:53so we need to get to the point of understanding more i wouldn't say everything but we need to understand
32:00more we do not understand gravity so bringing all these questions together in a unified theory is the quest
32:08and the higgs boson was discovered in 2012 today we understand it much better we have moved from
32:15discovery to precision and we are doing precision physics right now we are going to stop the lhc in
32:21july this year for three years and we are upgrading it with more strong magnets more intensity and we'll be able to
32:29take in one year all the data that was taken in the last 15 years so that's the kind of power that the
32:36lh the hl the high luminosity lhc is going to bring for us and then who knows what's in the offering we
32:43have no idea what we will find over there so it's not only about the physics it's also about data
32:49management governance ai and all that we already said but engineering i mean it is mind-boggling awe-inspiring
32:56awe-inspiring to see the scientists and the engineers from all over the world come together
33:02and build something that is a single unit of an equipment of 27 kilometers
33:08and then bringing it up to speed to handle these kind of data and events and the matching between
33:17i mean try throwing a little marble in a pond uh 30 kilometers away that's not this challenge i'm
33:24talking about this is like throwing a marble to new york somewhere you know so the challenge the
33:30electronics and the everything i mean the triggering and the um let's call it instrumentation challenge
33:38is so huge that finding solutions actually is building the infrastructures of tomorrow in countries
33:46like india for example where i do believe that long-term vision and long-term thinking for capacity
33:53building in every aspect is actually being unleashed as we speak and uh all right how about for astrophysics
34:00i mean the uh well um uh i mean i do remember uh a change in the model where we suddenly understood
34:08that the universe isn't just expanding but it's accelerating in its expansion and that kind of changed
34:15the way we have to think about the way the universe is evolving um are there kind of going to be do you
34:20think what would be the next big news story that might hit us um in the physics of the very big
34:27prediction is very difficult right especially about the future um we we don't we don't really
34:32know this stuff comes from left field so this this uh story you told about the the discovery of dark
34:38energy at the end of the 90s nobody was expecting it and it basically changed the way that we had to
34:43look at the universe so as data comes in we are going to to have to basically take a look at our
34:50model and just make sure that it's doing what we think but it has holes in it right we we do not
34:55know where the universe came from we can measure the evolution of the universe back to some ridiculously
35:00small time after where we think it began but is was it really the beginning or was there something
35:07else before that and part of the reason we can't answer these questions is that particle physics and
35:12cosmology we speak different languages and we we cannot we cannot talk about the very small and very
35:18large in the same sort of maths and this has been a problem for a hundred years now einstein on
35:24his deathbed was working on trying to basically smooth over yeah he failed and we still feel like
35:31we're a long way away so one of the challenges it seems that we've got ahead of us is how to merge you
35:37two together to make a single uh scientist who understands both the small and the very big yes
35:43uh so a chance now for some uh questions uh from the audience and look at those those arms go up um
35:50so do we have a microphone that um i'm going to start with this young chap down here who might well be
35:56the next uh scientist who unifies uh these two theories um hopefully these stories have inspiring
36:03been inspiring him uh to to think big and small hello i'm aram uh the most fascinating thing about space
36:11and science i can think about is vermal and singularity but for you what is the most fascinating
36:17thing about space or science well for me um one of the most fascinating things is that we we have black
36:26holes in the universe now these were written down um by schwarzschild back in 1916 and everyone thought
36:34well this is a crazy thing he said that it was places in the universe where where things have completely
36:38collapsed gravity becomes infinitely strong and everyone just went well that's just math's going
36:43a bit crazy but then in the 1960s people started to look in the middles of galaxies and they were going
36:49there's some really weird things going on here and there was huge amounts of energy coming from tiny
36:54tiny places and we've we've worked out that that can only be a black hole and in fact it turns out
37:01there's not just one black hole in the universe we've now seen that there are probably trillions of
37:06them and so the fact that these things exist they they were like derived mathematically again a long
37:12time ago and they exist in the universe it makes me wonder what else could be out there we haven't
37:17explored all of the mathematics yet so black holes for me are really really cool but i think things like
37:23wormholes might actually be a possibility that we might be able to travel huge distances by bending space
37:28and time enough so hopefully one day you can work that one out yeah and uh your choice of uh i mean
37:37we've covered many but um yeah i mean for me it's fascinating uh how fiction science fiction writers and
37:45authors write amazing stories like isaac asimov and then in the end it becomes true and that is what
37:53uh i i am inspired by and i would also encourage you to read more about science fiction and believe
38:00me in my lifetime i've been very fortunate to see such transformational things happen that i could not
38:06believe when i was a kid like you and i think that's the importance of imagination that it's certainly
38:11important to be a novelist to have a good imagination but to be a really great scientist as well imagination
38:17and creativity is absolutely key to be able to imagine the impossible and then show why it is
38:23possible um i'm going to take uh the woman at the back there in the white um yeah keep your hand up yes
38:29exactly
38:34um so sorry yeah i shouldn't gender people because um it's always a big mistake even the best times but
38:42yeah so as you spoke on um perhaps like the holy grail of current physics would be
38:47the discovery of the graviton right which is proving very elusive are you all aware of any
38:53current or upcoming experimental setups that you feel optimistic could do that and conversely are
38:58there any experimental setups that could conclusively prove that gravity is not quantum
39:07it's a very difficult uh question to answer yeah so so the only place that we currently think that we
39:13could find the quantum signature of gravity i is there a single language that we're written in
39:19is when black holes collide so what would happen is is that that quantum nature would be written
39:25into the way that the signal that we get from these black holes now the problem that we have is that that
39:31signal is going to be very very subtle and the data is still quite noisy so people are proposing you know we
39:39we need the next generation of gravitational wave telescopes and they are planned i believe india
39:45has plans for one yep yep and so you get more and more of these telescopes such we can get better
39:51and better data people have tried looking but at the moment there's no sort of apparent signature in
39:58what they've seen but as i already mentioned sometimes um answers to these questions come from left
40:05field and somebody will do an experiment one day and just go oh that doesn't quite you know behave
40:10the way that i expected it to so gravitational waves are the the hope but left field might actually be
40:16the answer oh we're running out of time so i want i'm going to choose one more question which is going
40:21to be uh this uh woman down here great you have a question oh thank you excellent yes my question is this
40:28as a layman as somebody who doesn't uh who is not very much into science i i wish to locate myself in
40:36my world as far as possible perfectly now uh there are some things you know i want to be a rational person
40:44there are some things which are very obviously rational and i can subscribe to them there are some
40:50things which look obviously irrational i stay away from them but there is a whole lot of midground where
40:55i'm not able to take a decision about whether these kinds of beliefs should be called rational or
41:01irrational for example i mean when i think that everything can be decided by physics for me and
41:07if i trust in the scientists i will know who i am but when i look at things like infinity yes i'm just
41:14trying to if i look at questions like infinity i feel i can't really comprehend them so what i'm trying
41:19to say is that when i look at like supernatural answers or i spirit or whatever xyz yeah great
41:26i'm gonna because we're running out of time i'm just gonna because i think you know one of the big
41:30questions at the heart of that is you know can physics explain it all i mean you know can physics
41:35explain it all yeah go for it so science needs evidence and questions like those when they will be
41:46improved like 30 years ago 40 years ago i would not believe that i would be able to make a phone call
41:52to new york without a cable and that's where all this quantum and science comes true from the equations
42:00to reality and then science stops philosophy begins let's give our storytellers a great round of applause
42:08for some wonderful stories of science thank you very much
42:14very quick question what has physics explained two things time reversal invariance and to consciousness
42:24oh my gosh we have you got another hour so uh time reversal and consciousness um in minus i
42:30suppose we're going to use some negative time here but um um i i think i i mean have you got a quick
42:35answer okay uh consciousness who knows we can't even define consciousness properly time reversal
42:44maybe but it's not completely solved maybe but they're not yet so look i need a job i need money
42:51so i'm not going to solve every problem today right so anyway let's give them a big round of applause
42:56again thank you so much for coming
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