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Dark matter. Dark matter. Dark matter. My name is Kristy Hopley and I'm interested

answering the biggest questions that physicists today have about our known

universe the best description we currently have of our universe is a

model called lambda CDM lambda was found in

Einstein's equations and is called the cosmological constant it's currently

theorized to represent an entity we call dark energy CDM is the acronym for cold

dark matter as opposed to its theoretical partner hot dark matter cold

dark matter is thought to make up 99% or more of the entity which we call dark

matter dark matter and dark energy the two components of lambda CDM are thought

to make up over ninety five point five percent of our known universe but we

just don't know anything about them I talked to India for is well for a good

perspective on how to think about these two entities as interacting in our

universe but I don't know how you think about dark matter and dark energy but I

like to think of it as - - like evil not - evil twins by two brothers making a

puzzle and so dark matter is trying to build the puzzle bring all the pieces

together and build the structure of the puzzle

whereas dark Energy's like taking the puzzle pieces that I'm running away and

so dark matter has to run get the puzzle piece and put it back and like as time

goes on in the universe automatic he's running them further and further and

further away and that's exactly what's happening in the universe so Dark Matter

provides the gravity for all our structures to form like the clusters the

filaments if you've ever seen maps of the large-scale structure of our

universe it kind of looks like a huge spider's web in 3d and whereas dark

energies is energy providing this kind of outwards expansion and so it's

slowing down this structure formation so dark matter and dark energy make up a

huge proportion of our known universe but where did these ideas come from so

you think is about 1860 so astronomers are looking at the

motions of the stars and they essentially start to see that the stars

didn't obey the laws of Newton as would be expected given the amount of the

number of stars that we could see we're out there making some assumptions about

typical mass of a star so one of the most interesting only contributions seem

to come from the north Kelvin which is a nice link to Scotland up here

essentially it's just a case of looking at the movements of stars and trying to

understand how that fits in with the user stores as we know and love them and

it doesn't quite work so even back in the late 19th century people were

realizing there must be more stuff out there than we can see and we couldn't

see it so it became known as dark matter I guess the reason why this really

starts to be seen as the father of dark matter is partly because of the

character of zucchini which is an outstanding interesting controversial

figure kind of a personal antihero but also because that was the era where

things started to be quantized quantified much better so that it wasn't

just supposition and sort of all things don't work so well it was really these

are the specific numbers that we need to get to work and this is how much this

dark material there might be and then again whose so he was the observation

that led to the hypothesis of there being matter kind of then fell out of

favor until the 50s and then 16 especially where rotation cuts were

being measured by Rubin and came forward and several others as well and again

that then provided even more robust data that suggested there was this extra

stuff out there so the main hypothesis for us is that dark matter is a new type

of particle and again we might be wrong okay that's good let's call that a

working hypothesis now standard model is extremely successful explain in physics

in of elementary particles okay we know for

example that the building blocks of our universe and everything that we're made

of leptons and quarks so electrons for example the quarks that make up protons

neutrons etc with also discovered neutrinos and we also understand forces

the fundamental forces as the interchange of also fundamental

particles we've got a set and a b-bow some some the recently discovered Higgs

boson now known of the known particles none of the particles that we've been

able to discover to discuss within to describe within the standard model can

be the dark matter we're looking for a particle that is neutral that is stable

and cosmological scales that I have some decades yet and therefore that that

means that we have to invent something and we have to put it into the structure

of the standard model so for more than one reason

Dark Matter theoretically needs to exist but how would we go looking for

something that you can't see from from the experimental site we can also ask

you know how do we even think about measuring dark matter if it's dark so

there are different kinds of tests that have are devised and they can be divided

up into things called direct measurements indirect measurements

astronomical and Collider so the idea is that the Dark Matters hypothesized maybe

as some kind of a particle we don't know what but let's suppose it's some kind of

particles that are floating around in the universe I can talk a little bit

about that after this so suppose these particles are wishing through you know

going past the earth or something like that and so one of the ideas of

experiments is that well let's suppose that we put some some other particles

that we can measure like heavy elements right and into it into a big cavity and

let's just let them sit there and if they start jiggling around then

something clearly had to gone through and we know certain things that can

cause this motion I mean like light and radiation and everything like that

so experiment let's try to control all those kinds of backgrounds in other

words they go deep underground where there's going to be less radiation etc

so they try to control all of these parameters and so then if they start

seeing motion it might suggest that some kind of an unknown particle is actually

struck one of these heavy nuclei and that might give us a hint on sort of

the flux of dark matter that's going through and so that's what I do I work

on experiments with a couple hundred other people from around the world lots

in the UK but many more in the US and then also near Russia Portugal in and

South Korea on experiments like luck Zeppelin which is a large liquid xenon

basics detector it's essentially a large bucket of liquids at home and if these

dark matter particles these particles are going through it and one does bounce

off a xenon atom it will produce a big splash of light and some and some

electrons that will try and detect huge experiments like luck Zeppelin or Al's

I'd have a lot of hope of finding dark matter particles in the future if they

do exist but it's not the only approach to looking for them here we had to blow

be mine to find out about a different way of thinking about the problem I'm

looking at experiment called drift and drift stands for directional recoil

information from France drifts a bit unusual in the search for

dark matter it's not like LZ or some of the biggest scale that much accepted out

there it's it uses completely different technology and it's almost a different

approach if tirely to looking for dark matter

drift unlike the majority of Davos incentives is a directional Thomas

detector so simply put that means that when we seen an event inside of drift

well it won't drift detect something it doesn't just find it as like a point

particle it doesn't give it just immediate information it also plates

at track if you were so instead of being a point event you get a couple of

millimeters track depending on being here the possible

and from this track you can infer the direction from which the particle came I

mean origin of the particle if you will and this is really useful when it says

to put dark matter in particular so due to the way we move through our galaxy

through the universe we don't expect moving with the damage

that surrounds us we think that dark matter is done by ambient air it does

have motion but it doesn't really move with us if it's just ambient and we move

through it so relatively speaking if we're moving through something it's

ambien in our reference frame that ambient thing in this piece dark matter

would be relatively moving towards us like a wind so when we call this

phenomena the WIMP wind we suspect that as we're moving through

the universe we should be experiencing this with wind as we Traverse

and this is where the directionality of drift comes in so drift aims to map out

all the particles that it finds while it's running what you can do with that

information is you can plus it those galactic coordinates of each event onto

the night sky so ridge event that you find and you pinpoint it almost to a

picture of the night sky let's say

don't much of us exist and we find the number of damaged your interactions they

should all be coming from the same direction because they were they're all

part of this width we're all moving through them in the same direction and

if you look at the night sky it should be in the direction of the constellation

of Cygnus so no other possible would give us this behavior neutrinos or new

trailers you know the full plethora of backgrounds available they were all in

them quitters or random nothing would act like I matter it's

totally separate due to its characteristics but we suspect that the

case and so if we did see a hot spot in the

sky due to a number of events all fit in the same location we can almost

completely say they it's confirmed that my three faces so that's why we run

rivers there's indirect measurements we can look for annihilation so the dark

matter is a particle and as with as with particles sometimes they can transmute

into other things like if you have an electron and and a positron and they hit

each other then they will turn into light

okay this it's a matter of antimatter type of thing so in general in particle

physics we can have phenomenon like that and it's the similar story with dark

matter and it's possible that through some interactions the dark matter can

turn into other kinds of particles and theorists have done various calculations

and you know there's predictions that Dark Matter in certain kinds of

astronomical Astrophysical phenomenon would produce abundances or higher

levels of antiprotons or positrons and things like that so these are indirect

measurements that we try to do we put up satellites or we do ground-based

measurements of you know the x-ray spectrum and all these other different

spectra and in the universe and try to see these sorts of excesses and once in

a while there's kinds of blips that oh this looks interesting but usually

everything can be explained by standard astronomy by standard symbology the

third way of looking for dark matter through experiment is astronomical

observations here I go to the Royal Observatory of Edinburgh to speak to

Professor Jose ins about how lensing can be used as a technique to find out more

about dark matter so what we we try and do most of all is look at lensing that's

my particular area is looking at gravitational lensing so if you if you

throw a ball in the air it will come down again and it starts off getting a

straight line but then gravity pulls it and bends it down towards the ground

again so we used that here of gravity curving the paths of objects what may be

less obvious is it also curds the path of light so if you shine a laser beam up

into into the sky it will actually bent very very very slightly downwards

towards the earth that's that's far too small to see with the naked eye you

can't see that by eye and it's too small in effect that you can't see it

absolutely an accepted most extreme circumstances so this was first detected

about a hundred years ago and by Arthur Eddington who was this fantastic early

twentieth century astronomer very very interesing mounted lots of really cool

experiments and he went to the island of tomé and príncipe riches of West Africa

during a solar eclipse and the reason he wanted to do this was that the only

thing powerful enough to bend like that we could see it was the Sun that's

anything with enough gravity to actually do this in general votes of bad idea to

point your telescope at the Sun because he will you will melt your eyes so you

have to go there the only time you can do that which is during a solar eclipse

so he found a cellar accepting he looked at stars around the Sun and he saw that

their apparent position was bent and moved by the Sun's gravity chewing

during that period and that was one of the experiments that led to us believing

Einstein's theory of general relativity that's our current and and best theory

of gravity so our whole understanding of gravity is built on this this disagree

this observation which is which is very powerful one so the theory and ideas

behind lensing are actually quite old however they may be in a lot of use

today I spoke to dr. Alexandra Aman and her upcoming projects using a technique

called weak gravitational lensing so I studied at Mozza using a tool called

weak gravitational lensing so as part of a team we observe distant galaxies using

our telescope in Chile and between us and those distant galaxies is the cosmic

web of the universe so the universe has a web-like structure made of dark matter

and the dark matter is is in clumps in the universe the dark matter is massive

so it has gravity and that gravity warps the fabric of the universe which we call

a spacetime so the the space-time gets curved now because of that when we

observe distant galaxies the lights no longer travels in a straight line it

also gets curved due to the presence of the dark matter and the gravity of the

dark matter so that means that when we take pictures of galaxies galaxies that

are far away their light because of the bending of their light path the galaxies

images appear distorted so the galaxies are a little bit more elliptical than

they really are now you can by measuring this distortion

by measuring this in effect we can understand where about

the stuff that the by measuring this distortion effects we can understand

about the stuff that the light passed through so we can understand the

properties of that matter direct observation there's only one way of

looking for a dark matter through the skies another way is to use simulations

to try and replicate what we currently see and then obviously if the

simulations replicate earth and universes like ours then potentially the

emphasis of that simulation in terms of dark matter are potentially correct this

simulation simulates what the universe would have looked like in a very very

early snapshot of time where you can see matter being drawn together into

structures it's important to know however the involvement of dark energy

is not represented in the simulation as the viewpoint sort of zooms out in all

directions at the exact same rate as dark energy would spread the particles

apart as gravity gets to work you'll see not only small tight spherical blobs of

matter congeal but they themselves form line structures so you'll see large

filaments of dark matter and you can see such filaments in that in the

distribution of galaxies today so just visually but also in terms of the

quantitative statistics that you can measure if these simulations really make

a very good match to the universe as we observe it so on the really large scales

hundreds of millions of light years across there's very little doubt that we

know truly how much matter there is and that the structures within it which are

mimicked today by the structures and distribution of galaxies are a result of

gravitational instability so what a lot of people in the field are trying to do

is to go beyond that and say well how can we use this information to tease out

what the physical nature of the dark matter may be

and for that you've got to go to smaller scales because as I said if you go to

the larger scales in the universe even ordinary matter what gas will fall

together in much the same way as the dark matter in fact in the other that

matter and the gas don't really separate until you get down to the sort of scales

of individual galaxies like the Milky Way so the hope is that by trying to

simulate not so much the large-scale structure of the universe but perhaps

the formation of a single galaxy like the Milky Way or even most interestingly

for some applications the smaller dwarf galaxies it's a Milky Way has satellites

the moment that you know the percent of its mass Clarence and so these little

dwarf galaxies and they're the smallest things we know from the universe and

those smallest units could reveal a lot about the nature of dark matter and

finally and maybe the best test of all the acid test I would say would be

Collider which is to actually produce a dark matter particle in Collider

experiments finding a concrete dark matter particle or producing one at a

collider would be a pretty compelling piece of evidence for the lambda-cdm

case so I spoke to Professor crystals theodopolis who works at CERN and in

project like a CLIs about how you might go about creating a dark matter particle

inside a Collider you would be looking for a collision where you have two very

energetic protons that collide and then nothing comes out

or maybe something comes out one direction but there's some imbalance

because you've created something that's invisible in the same way that you would

see in a galaxy dark a dark area and you you see that you think that this is

something that does not give you nice so it becomes invisible so you're looking

for collisions where there is a strongly balanced you have some particles go in

one direction but nothing on the other the detector hood looks very impressive

as an experimental sequencer and you say that okay I need to collect loads of

those to understand if this is something that maybe bass may be explained by the

atomic model or I find some very large number of those asymmetric collisions

that would point to to dark matter for example one of the things that we're

trying to do right now is you have the the experiment you have two proton beams

that collide against each other at a very very high rate so you have 1

billion collisions per second and you don't have the means you don't have the

resources to store every single one of those collisions you have a system which

is called the trigger which is a combination of hardware and software

some advanced algorithms that in real time trying to make an educated guess on

whether a particular collision looks interesting enough and has to be stored

for offline analysis or it looks very normal very boring and should be thrown

away so the output of this process is what we store and it's a very small

fraction so out of a billion collisions per second we restored only a thousand

so it's a highly selective process okay we store what we think is the most

interesting potentially interesting collision events that can contain

evidence for new physics or contain Higgs bosons that we want to study in

more detail you know that at this point it is fair to remind yourself that we

have been looking for years on years for these type events at CERN and we still

haven't find anything on the trigger is ignoring billions and billions of

collisions so what are the odds that your trigger is simply systematically

ignoring something that you would like to record so one of the there's an

ongoing effort and this is something actually we work you know

other people are working on this is to try to deploy a more sophisticated suite

of algorithms including machine learning into the trigger so even if you cannot

afford to increase the output rate of the trigger maybe if you have some

machine learning it will be able to look into the events that you throw out and

look for some anomalies maybe hey you think this is boring but I say something

that does not really make sense why don't we save this or let's try to

collect several of those to see if we find a pattern that your baseline

selection was going to throw away so we have these four different experimental

methods of looking for dark matter where do we go next I speak to phenomenologist

about the process of moving from experimentation to results and theory

the way we understand phenomenology in particle physics is the bridge between

theory and experiment so again is this dialogue of theorists having ideas that

have to be tested finding ways in which your new theories can give observable

phenomena and also reacting to experimental results at the moment the

experiment that I work in super CDMS and another experiments which are based on

liquid xenon I would say that we are the best at not finding dark matter

this is actually very useful information as well because it tells us faces or

theorists that many of the models that we were working with are either not

correct or they have to be revised so we have a results or lack thereof and where

do we go from there we go to the observatory where I speak to astronomer

about what their results and their data have told them about the searcher

dramatic tell so true that what we have seen is that the more data we have

collected in the last 10 20 years what happened there is that we have been

pushing all these potometer particle models to hire higher energies and that

always means that we are in our models too were pushing

antimatter models to routines where the matter behaves closer and closer to a

person fluid sir so that's what's being going on you know the more we work on it

closer the matter behaves well and that's what general relativity assumes

there is no quantum physics in general relativity so everything we've been

finding so far is that generativity this behaves extremely well I mean that

that's a theory it's extremely I don't know what a quantum physics I'm not an

expert in the field I don't know whether they can't say something like that

so after astronomy I look in the opposite direction to particle physics

where there are four possible candidates for what dark matter could be so so let

me just discuss briefly some of the kinds of dark matter particles that

theorists have cooked up so the one dark matter particle that's actually known to

exist is the neutrino okay so the neutrino is a very light particle it

interacts with almost nothing through measurements of beta decay and neutrino

oscillations we can put a bound that the mass of a neutrino is incredibly tiny

smaller than an electron volt so an electron itself electron volt is review

unit of energy or mass so like an electron is 500,000 electron volts so

that gives you an idea of how like the neutrino is the same time a neutrino

interacts with almost nothing so it's an ideal Dark Matter candidate you think

but if you actually understand the the history of the the time history of the

University of the neutrino in the universe and it used to interact to a

degree in the early universe and it was light and therefore it actually was a

form of hot dark matter and I've already mentioned that in simulations etc we see

that hot dark matter really doesn't explain the kinds of astronomical data

that we see so we can put a bound that you know neutrinos can be a part of the

mix but it would be less than 1% of the dark matter that we actually need so so

that's one candidate that we know of but it really doesn't work too well so so

then there's a whole slew of other possible candidates and I should say

from the onset that none of them have been observed but there's a lot of

theory that's been developed for all of so so one of the promising candidates is

the acción that's a another kind of particle so so there are there are

problems in the standard model with the the strong sector of the the for the

strong force that's the force that binds protons and neutrons together okay so

there are certain cemeteries that the acción helps through a stroke called

charge and parody and so that's the theoretical motivation for the acción

but it also turns out that if you follow this route of trying to to you know

ensure some cemeteries in the strong sector it turns out that the particle

that you actually create turns out to be very light and it turns out to be very

weak weakly interacting now although then accion is light it's so weakly

interacting that it never actually interacts with anything even in the

early universe and that's why it actually is not relativistic so it's a

it's a form of cold dark matter so as I mentioned cold dark matter is exactly

the kind of dark matter that we want so in that respect the acción is a very

promising candidate but only in that respect because as I said many attempts

to observe it and there's been nothing so another candidate it's called a

neutrally no so I mentioned that we're trying to build theories beyond the

standard model and so one of the most elegant ideas is an idea called

supersymmetry so supersymmetry in simple terms is an attempt to unify the forces

and the particles okay and and the consequences of trying to build a

supersymmetric theory is that you actually in a sense double the number of

particles in the in in the universe at least that's your prediction and and the

lightest of these particles of the new supersymmetric particles that you create

the theory tells you that this particle will be absolutely stable and now that's

a very important requirement for a Dark Matter candidate because dark matter has

to exist on cosmological scales timescales so the thing called a

lightest supersymmetric particle the neutralino is a very interesting

theoretical candidate for dark matter the other interesting thing is that a

lot about supersymmetry are things that are real predictions that you can test

in colliders and there were a lot of predictions made about supersymmetry for

the LHC and so far nothing has been found

and the neutralino was certainly one of the candidates that was hoped could be

seen in it the LHC or maybe it'll be a in a future Collider at a higher energy

scale so the thing about the neutralino is that it's it's it's fairly heavy it's

about you know there's there's a mass range you know on it I mean we don't

know the exact value but it has to be certainly heavier quite a bit heavier

than a proton maybe a hundred times heavier maybe a thousand times heavier

so it's quite a heavy particle but at the same time it's very weakly

interacting and it's actually part of a class of particles well we weakly

interacting massive particles or wimps as we like to call them so wimps have

other nice qualities if you actually look so if you look at the thermodynamic

history of the universe okay so the so what we understand is the universe is

expanding so that means if you go back in time it would be contracting so all

that matter would get into a higher higher concentrations and therefore the

temperature the universe would rise and if you go back to the very early phases

of the universe the temperature of the universe would be something like the

billion billion billion kelvins are higher okay really high and what happens

is that all of the other men prepar so what happens is that for example Noella

a hydrogen atom right it's it's a bound state of an electron and a proton and

there's a certain binding energy okay but when the temperature gets high

enough what happens is that there's enough energy that the electron can

simply keep getting knocked out okay of its bound state and it can just be free

and so what happens as temperature gets higher for example is that the first

thing that happens is that these these atoms they completely get stripped away

and they become a plasma so the protons run free the electrons run free and then

eventually the energy gets even higher and the proton itself gets ripped apart

and all the Corpse start running free and as you get to higher and higher

energies basically all you have is a is a soup just a plasma of all the

elementary particles okay so whatever is in your your fundamental theory would

just be floating around there and these wimps okay we understand some things

about the way particles that in the early universe they would have

interacted and then and they would have interacted a lot with with the other

particles but when the temperature of the universe became below the mass of

this particle then it would become heavy right because when the temperature

higher that means that basically there's enough energy that the particle to move

around but once the temperature becomes below its mass it becomes heavy and then

it stops interacting and it's kind of abundance then freezes at that point so

we can use the theory such as a super symmetric theory and we can use our

understanding of cosmology and we can actually make estimates of ham what

abundance of wimps we should expect to find today and the interesting thing is

that we do find from this kind of theoretical estimate about a 10%

abundance that would should come about from a wiff candidate and remember that

I said that dark matter is about 20% of the the content so with in order of

magnitude I mean a factor 2 is fantastic for pathologist so within orders of

magnitude we've seen like an intriguing candidate so you know if you put the

theoretical picture together you have cosmology on one side saying oh I can

predict at ten percent twenty percent abundance your particle physics saying

well here's a really elegant extension of the standard model and this dark

matter Kennedy just sits right there available in some sense for free if you

want to accept supersymmetry so you can see the motivation from a theorist point

of view and I emphasize from a theorist point of view that that this would be a

very intriguing candidate so you know a lot of interest has gone into trying to

detect and understand neutrally knows but again nothing's been detected

another super symmetric candidate is the gravity no so the gravity know is the

supersymmetric partner to the graviton the graviton would be the particle

associated with gravity so that is an interesting candidate but the problem is

it's very weakly interacting it's very light there's very few other signatures

we couldn't possibly hope to find it in a Collider but as far as theoretically

you know this could be another candidate for slightly broader perspective on the

theory I speak to one of enemas most famous theorists Professor Peter Hayes

where he thinks the future theory is headed

I mean if somebody with interest in the basic quantum field theory for particle

physics I'm really

an enthusiastic law so far unverified theories like supersymmetry where there

are candidates for dark matter already embedded in the theory but unfortunately

as far as the big machine at CERN is concerned no experimental evidence yet

for it so I mean as a theoretician I don't really see how we we can end up

with a theory which unifies gravity with all the other forces without having

supersymmetry it's the mathematical framework which makes it possible in a

way which was not previously possible so where else do we go if supersymmetry is

not right I don't know if particles such as the ones finding supersymmetry

theories are in fact wrong all hope is not lost for the search of diamond to

some physicists have come up with a very different way of thinking about the

problem and here I have to the observatory did you write it but yeah

there's a whole whole range of theories one theory is maybe maybe we've got the

whole theory of gravity wrong in the first place our our inference that there

is dumb energy out there comes from looking at gravitational system so

looking at the universe and then saying hey we know the lots of cavity so here's

what's happening perhaps we just have those laws of gravity wrong and maybe

it's that we've misinterpreted what we're seeing because we're expecting

them to behave under the gravity that we used to see that could be wrong and

there's lots of theories about how that could be wrong and so if we've

investigated a lot of these things so we've said well what if what if gravity

behaves differently in dense environments compared to empty

environments that might explain something that would be why we can be

here on the earth and all the experiments we do are very consistent

with our theories of gravity because we're in a dense environment with lots

of matter around but maybe out in the empty void regions of space well there's

no matter maybe the laws really change in those situations maybe suddenly it

just switches to a different kind of mode in those environments and that

that's a strong possibility to that we're investigating right now and

perhaps perhaps these these laws changing

from contexts and it's hard to write on a theory that sort of makes sense of

what we do now because we have very very strong measurements of now between a few

specific cases so we know very well on like on the earth and the solar system

how well copper tea works we know exactly how it behaves because we have

incredibly precise measurements so anything we come up with has to has to

reduce to that in some situation but not in others so it's in a very delicate

balancing act when writing down a mathematical theory of this stuff to

something that works with what we know but also explains the weird stuff

suggesting that Newton's fundamental laws of gravitation might be wrong may

seem like an insane thing to do however completely revolutionising the way we

thought is what made these people famous so I spoke to a philosopher Jelena Sami

on the process of completely revolutionize on the way you think what

will happens in specific historical period when the community has to take a

decision and somehow decide whether to embrace Copernicus or not over their

embrace you know lambda-cdm or not and what yeah what are the factors that in a

way explains and justify the formation of scientific consensus around the

theory over open another those raises interesting question I think from a

philosophical point of view because it's a question of looking not just on the

evidence about and how sometimes the evidence can be evidence for alternative

hypotheses and all those different alternative hypotheses can do different

justice to the evidence in terms exactly of explaining versus accommodating

versus evidence from experiment or evidence from computer simulation and I

think those are the questions that philosophers obviously ask so I don't

know I tend to think that obviously it's the job ring of scientist to do the

science and I don't I don't like to think of philosopher system on there

I don't know prescribe or give normative constraints where the scientists should

do but I do think that there are some questions there questions about the

method the models the they roll up the simulation and then the

nature of experimenting there are generally philosophical questions those

are questions that work in scientists that just wouldn't consider as general

scientific questions because they have stemologica questions questions about

human knowledge I will form knowledge of how our knowledge evolved and what

countless reliable knowledge and so in that sense of in philosophy of science

has an important role to play for for science but simply because there are

gaps in there in the normal picture that work in scientists just don't have the

time and don't know if I necessarily did that the skills of the resources to

address and so that's that's the space for philosophers of science I think to

come up chipping and and provide that contribution so we have looked

underground and experiments around the LHC and up into the skies to try and

find out what the nature of dark matter could be the theories that come from

this have ranged from exciting new particles to a perfect fluid just simply

a mistake in our calculations so how we know for sure

well eyes in the future of doctor experiments I speak to dr. Alexandra

Armand to find out what the future of sky surveys holes yes it's a really

exciting time for lensing because there are three ongoing surveys and they're

all in healthy competition but they are really just developmental work for the

upcoming surveys now these upcoming ones will see first light in the next decade

and they will really provide answers for for what dark matter is and where it is

and they'll really deliver high precision astrophysics so there are

three of them and in tandem they'll is where their power lies so there's Euclid

satellites now that will be launched into space and so it will remove our

worry about the effects about atmosphere distorting creating further distortions

in our images and there's also the LSST so the large synoptic survey telescope

now that one is also based in to live and it was Surrey at the night sky every

three nights so it'll just keep cutting around and eventually by stacking all

the images create one of the deepest largest images

of our universe so surveys now will map a size of the sky that's about the size

of a moon for example whereas LSST will do the

entire southern hemisphere so it really will provide groundbreaking things I

think changes for the field and then also in along with there is you have

desease and the dark energy use spectroscopic image and this one this

survey is a bit different so it takes spectroscopic images so instead of it

being optical images of galaxies I think John will talk about this but it will

precisely instead of it being optical images it will take spectroscopic images

and that allows you to see not only exactly where the galaxy is but how fast

it's moving away from us and and when you when you have a combination of

techniques so weak gravitational lensing is super useful for understanding dark

matter but we're at the stage where if you use a combination of techniques and

probes together for our analyses they give a lot of a lot more informative

results so the future of astronomy seems to be looking up but have a direct

detection for dark matter and and have you know potentially an ecosystem of

experiments to borrow a phrase from someone else it's a you know we don't

know what this stuff is Dark Matter candidates span 40 orders of

magnitude in mass so we need to be casting our net you know very wide and

whilst also going deep for those where we think you know we've got the most

chance of finding something at present given technology and given the state of

our knowledge so things like you know a generation 3 Dark Matter detector you

know needs to be built especially if it can open up an inter sort of a rare

event search observatory rather than just being rather than just being wimp

only and expanding to different types of dark matter expand parser as well

neutrino physics and rare event searches and making observatory I think that's a

very that's a compelling case but then at the same time broaden open up look at

all these look at lots of other theories that we can go after but you got a map

that to UK expertise and experience as well you can't just say this is a good

idea let's go try that it'll take time to build up the skills to do that

in many cases but that's fine that's what

we do experimentalist now we go back to Professor Peter Higgs to talk about

where physicists should look in the future for new physics beyond the

standard model neutrinos that we know to me in terms of the experiment

experimental evidence on where theories in particle physics should go neutrinos

are very very important because they I mean they can be accommodated within the

standard model but if you go back to 9 to the 1960s when well say 1960 which

was when Shelly glacier first formulated that an su 2 cross u 1 electroweak

theory it was on the assumption based on what was known at the time that the

neutrinos had no mass now it's clear that clear that that's wrong but but

better so we you know we we can sort of stretch the standard model a bit but it

isn't very natural to have massive neutrinos in it so I think the the

evidence on on the new trainer spectrum and all the parameters of the masses and

the mixing and all all this sort of thing is it's very important but

unfortunately the data come in very slowly so you have to wait many years

before you get the answer well III think that's where the probably where they

present standard bubble is going to be shaken up and and

and there's theoretical directions in particle physics really determined as

the future excites grows so does the need to work together as a scientific

community and collaborate I speak to dr. Shane Reilly who's been working on a

collaborative project luck Zeppelin and they need to work together as a

scientific community and potentially end up doing science as a planet

interestingly right so that's the scale right so ask your Dark Matter particle

gets smaller and smaller your detector has to get much more massive to look for

it and as a result you bring all these people together and you build these

large collaborations and it's actually a beautiful thing right I think I think

there's these physics experiments you know so many Institute's so many

universities from so many countries all working together is a oh in the you know

Oh in the hope of finding something that may or may not exist is a pretty good

moment in human human history things that actually unites countries all right

that's what

you

For more infomation >> Shining A Light On Dark Matter - Duration: 43:44.

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Weingut Schwan: Das Konzept von Pink Swan, White Swan und Dark Swan - RegioWein 2018 - Duration: 5:57.

For more infomation >> Weingut Schwan: Das Konzept von Pink Swan, White Swan und Dark Swan - RegioWein 2018 - Duration: 5:57.

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Steel Beam the Dark Conductor Live Stream - Duration: 1:19:22.

For more infomation >> Steel Beam the Dark Conductor Live Stream - Duration: 1:19:22.

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MYSTERY BOX FROM DARK WEB - Duration: 6:43.

I BUY BOX FROM DARK WEB

THIS THE BOX

WE CAN SEE WHAT INSIDE

For more infomation >> MYSTERY BOX FROM DARK WEB - Duration: 6:43.

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Follow Me On Twitter @Anejthelegend27 ThisVideo Is Just Dark - Duration: 0:44.

dun dun dun ALI A is better than ninja

i hope you died

kys

subscribe to pewdiepšiie he is stealing memes

h

a

g

a

y

i do not associaet with you

jk

lolol

tnk for watching this video now die

For more infomation >> Follow Me On Twitter @Anejthelegend27 ThisVideo Is Just Dark - Duration: 0:44.

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Tails from the Dark Dragons Inn: Season1 Episode18: Full Subtitles - Duration: 53:49.

For more infomation >> Tails from the Dark Dragons Inn: Season1 Episode18: Full Subtitles - Duration: 53:49.

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Majaicans - The Dark - Duration: 4:27.

The wind was blowing in the dark

The rapist running down the park

Headed straight for the bullet that...

was intended for your dad.

(Here´s PC Jones)

PC Jones picks up the bones

And wonders if it´s good or bad

Will there be a funeral? Will anybody feel sad?

Will there be enough uniforms to cover it all up?

The wind was blowing in the dark

(inner city)

Corrupt MPs getting high on smack

(feeling pretty)

Headed straigth for the life that...

good Oxbridge boys should never have.

(Here´s PC Jones)

PC Jones picks up the bones

And wonders if it´s good or bad

Will there be a funeral? Will anybody feel sad?

Will there be enough uniforms to cover it all up?

The kids were screaming in the dark

Child molesters trying to dodge a shark

Headed straight for the maiming that...

had been a long time coming but...

(Here´s PC Jones)

PC Jones picks up the bones

And wonders if it´s good or bad

Will there be a funeral? Will anybody feel sad?

Will there be enough uniforms to cover it all up?

Ugly crime scene

Ugly crime scene

Ugly crime scene

Ugly crime scene

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