Documentary - Atom: The Illusion Of Reality (Jim Al-Khalili) | Science Documentary | Reel Truth Science
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The final part of Professor Jim Al-Khalili's documentary series about the basic building block of our universe, the atom.
Al-Khalili explores how studying the atom forced us to rethink the nature of reality itself, encountering ideas that seem like they are from science fiction but in fact are a central part of modern science. He discovers that there might be parallel universes in which different versions of us exist and finds out that empty space is not empty at all, but seething with activity.
The world we think we know - the solid, reassuring world of our senses - turns out to be a tiny sliver of an infinitely weirder and more wonderful universe than we had ever conceived in our wildest fantasies.
The story of the discovery that everything is made from atoms, one of the greatest scientific breakthroughs in history, and the brilliant minds behind it.
Transcript
0:06
[Music]
0:14
[Music] [Applause] [Music]
0:22
in 1912 in a hot-air balloon about three miles above the ground
0:28
an Austrian scientist called Victor Hesse made on the most astonishing discoveries in science up here Hess
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found that incredibly mysterious ways of energy were pouring in from outer space
0:41
and streaming through the earth they were incredibly powerful and yet unlike anything anyone had ever seen before
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they were called cosmic rays at the same
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time in laboratories down below scientists were studying equally mysterious and equally powerful rays of
1:00
energy pouring out from the interior of atoms energy known as radioactivity
1:06
mysterious rays from the vast emptiness of space a mysterious rays from deep within the
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atom the tiniest building block no one really understood what they were let
1:17
alone believe that they might be connected then an incredible story unfolded cosmic rays and radioactivity
1:25
turned out to be connected in a way so shocking that it beggars belief the
1:30
discovery of this connection would force us to rethink the nature of reality itself the world we think we know the
1:38
solid reassuring world of our senses turns out to be just a tiny sliver of an
1:43
infinitely weirder more wonderful universe than we could have ever conceived of in our wildest fantasies
1:49
our reality is just an illusion
1:56
[Music]
2:06
[Music] in the years up to the mid 1920s the
2:12
Atem revealed its strange secrets to us at a prodigious rate as it produced one
2:18
scientific revolution after another in
2:24
1897 marie curie studied strange rays pouring out of some rare metals she
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called them radioactivity then in 1905 Albert Einstein
2:38
conclusively proved the existence and size of an atom by studying the way
2:43
pollen moves in water a few years later
2:50
the New Zealand Ernest Rutherford performed an experiment in Manchester that revealed
2:55
to him the shape of the interior of an atom scientists were shocked to discover
3:07
that the atom is almost entirely empty space the question then became how could
3:15
this empty atom possibly make the solid world around us the answer to that was
3:21
worked out by a group of revolutionary physicists in Denmark
3:28
they proposed that the world of the atoms ran on principles which were completely different to any mankind had
3:35
ever seen before it meant that the atom the basic building block of everything
3:41
in the universe was unique and perhaps outside human comprehension then a
3:50
scientist explored the nucleus the tiny heart of the atom they found it bursting with powerful
3:56
energy this discovery gave them the potential to bring about the destruction
4:02
of the earth but in a shocking turn around it also gave them a fundamental
4:08
understanding of how the universe itself was created and yet despite this the
4:16
journey to understand the strange and capricious atom had only just started
4:23
[Music]
4:29
in 1927 a young man was studying at the mathematics departments of Cambridge
4:35
University shy awkward clumsy and frightening ly brilliant his name was
4:43
Paul a dream Maurice Durham it's probably fair to say
4:53
that Paul Dirac isn't a household name but it should be he was recently voted
4:59
by other physicists as the second greatest English physicist of all time
5:05
second only to Isaac Newton and he deserves the accolade all the brilliant
5:10
minds that pioneered atomic physics were left trailing by Dirac aghast at the
5:16
sheer boldness and lateral thinking in his work when Einstein read a paper by
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the then twenty four-year-old Iraq he said I have trouble with Dirac this
5:33
balancing on the dizzying path between genius and madness is awful in 1927 for
5:42
reasons no one has ever really fattened Paul Dirac set himself a task which was
5:47
monumental in its to unify science to bring its scattered
5:53
parts into one beautiful entity and what
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this meant above all was to unite the two most difficult and counterintuitive
6:04
ideas in history here's what Dirac was trying to reconcile
6:10
first there's quantum mechanics a set of mathematical equations that describe the
6:15
atom and its component parts then there's Einstein's special theory of relativity which a first glance seems
6:22
completely unrelated to the atom it deals with loftier matters like the nature of space and time themselves one
6:30
of its consequences is that objects behave very differently when they travel close to the speed of light
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[Music]
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the first thing you might ask is why would anyone want to reconcile to such
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different theories well by the late 1920s the equations of quantum mechanics
6:54
were consistently getting the wrong answers when describing electrons while the constituents of atoms as they moved
7:02
at very high speed but for Dirac there was a much more esoteric motivation he was once quoted
7:08
as saying that a physical theory must have mathematical beauty so for him the
7:15
fact that quantum mechanics and relativity were reconciled wasn't just inconvenient it was downright ugly
7:24
so around 1925 in Cambridge Dirac put his extraordinary mind a mind that even
7:32
Einstein had trouble keeping up with to work
7:38
this is room a for new court and it was Dirac's original study I guess the
7:45
original fireplace has been boarded up now but it was here that Dirac tried to
7:50
understand and bring together the two new ideas of 20th century physics now
7:56
word is Dirac would sit here in front of is blazing fireplace and try and
8:01
understand and bring together these two different theories into one unified
8:07
picture one single equation for three
8:18
frustrating years he labored alone
8:24
then one evening in early 1928 he had an amazing revelation the only way I can
8:31
explain what happened is to say that the equations of quantum mechanics and special relativity coalesced inside
8:38
Dirac's mind Einstein's description of space and time somehow stretched and squeezed the
8:45
existing equations of the atom they bent and twisted them into all sorts of new weird and wonderful shapes then guided
8:53
by his unshakable belief that nature's laws must be beautiful Dirac honed in on one equation an
9:01
entirely new description of what goes on inside the atom [Music]
9:08
[Applause]
9:14
Garret knew it was right because it had mathematical beauty
9:20
[Music]
9:27
[Applause] here it is the Dirac equation gamma mu
9:33
into ID mu minus e a mu pi equals m pi don't try and understand it just look at
9:40
it a marvel as far as human achievements go is up there with King Lear
9:46
Beethoven's fifth or the origin of the species because hidden in these symbols
9:51
is the perfect description of how reality works at a fundamental level
9:56
it's the key to nature's secret code [Music]
10:02
with perfect mathematical elegance Dirac's equation describes an atomic
10:09
particle traveling at any speed right up to the speed of light that much Dirac
10:17
was expecting to achieve but when he looks at his own equation more carefully
10:23
he noticed something breathtakingly revolutionary about it he later said his
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equation knew more than he did in essence Dirac's equation was telling him that
10:34
there's another universe we've never noticed before
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[Music] that's because instead of his equation
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having one answer it has two the first
10:52
describes the universe we know made of the atoms we're familiar with the second
10:58
describes a kind of mirror image to our universe made of atoms whose properties
11:03
are somehow reversed now science fiction fans will know what's coming as well as
11:09
matter directs equation predicts the existence of antimatter
11:17
Dirac's theory seem to say that for everything in our known world for every
11:22
part of an atom every particle that can exist a corresponding antiparticle with
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the same mass but exactly opposites in every other way and just like a world in
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a mirror a universe made of antimatter atoms would look and work just like ours
11:41
it will be perfectly possible for me to be made entirely out of antimatter an
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seme would look and behave exactly the same as original me and indeed it's
11:53
possible that out there in the vast expanses of the cosmos there are stars and planets and even living beings made
12:00
out of antimatter and there's one final prediction of the Dirac equation as its punchline it states that matter and
12:07
antimatter must never come into contact because if they do they will annihilate
12:12
each other in a fierce conflagration of pure energy the combined mass of matter
12:19
and antimatter would convert completely into energy according to Einstein's
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famous equation e equals MC squared so if I ever do meet my doppleganger we
12:30
would explode with an energy equivalent to a million Hiroshima sized atom bombs
12:43
all this sounds like science fiction and indeed the idea of antimatter has
12:50
inspired huge Suede's of it but the truth is antimatter particularly
12:55
antimatter electrons called positrons are made routinely now in laboratories
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positrons are used in sophisticated medical imaging devices called PET
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scanners that can see through our skulls and accurately map pictures of our
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brains but back in the 1920s the initial
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reaction to Dirac's equation among physicists was deeply skeptical even Dirac himself had trouble believing his
13:25
own results antimatter seemed such a preposterous concept then came
13:31
resounding confirmation of the Dirac equation and all it's paradoxical implications and it came from the most
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unexpected place outer space in 1932 physicist Karl
13:46
Anderson was working here at Caltech in Los Angeles when he made an amazing discovery
13:52
he'd been studying cosmic rays these are high-energy subatomic
13:57
particles that continuously bombard the Earth from outer space to do this he used a device called a
14:05
cloud chamber this is basically a vessel that's filled with a fine mist of water
14:10
vapor this shows up the tracks of the particles as they stream down through
14:15
the vapor and placed inside the magnetic field these tracks will be deflected one
14:21
way or the other depending on the electric charge of the particle so positive particles tracks been one way
14:27
negative the other anderson found evidence of particles that look exactly like electrons but which are deflected
14:35
in the opposite direction he had discovered Dirac's antielectrons
14:40
particles of antimatter the Dirac
14:48
equation is an impressive achievement its prediction of the existence of antimatter using abstract mathematics
14:55
alone will be enough to make it a significant milestone in the history of human thought but within just a few
15:03
years of publication first Dirac and then others sense that his new equation
15:09
was telling them something profound something completely new about nature
15:14
and they were right but the revelation hidden within Dirac's equation would
15:20
take the best efforts of the greatest minds 30 years to uncover
15:26
the problem with Dirac's equation was this although it was incredibly powerful
15:31
and had led to the discovery of antimatter ultimately it could only describe a single electron it fails
15:39
completely to explain what happens when there is more than one electron present what was needed was a new theory a
15:47
theory which explains how electrons interact with each other
15:54
and that turned out to be the most difficult question of the mid 20th century but when an answer came it was
16:01
to bring with it an unexpected revelation this office in Caltech just
16:13
outside Los Angeles used to belong to the great Richard Fineman in our story of so many geniuses
16:21
of science Fireman stands in my view second only to Einstein in the list of greatest 20th
16:28
century physicists you see Simon wasn't just a common or garden genius many
16:35
refer to him as a magician he was so smart such an innovative thinker and like Einstein he became a mythical
16:42
figure and certainly a household name fireman was a larger-than-life character
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he he had a huge personality he loved cultivating and telling anecdotes about
16:52
himself he used to frequent strip clubs he had affairs with his students he was
16:58
even rumored to go to orgies but his greatest contribution to physics was the
17:04
part he played in developing the next phase of quantum mechanics [Music]
17:11
Fineman and his contemporaries were attempting to pick up the atomic torch from Paul Dirac and develop a theory
17:19
that took our understanding of the atom literally a quantum leap further like
17:25
Dirac's antimatter equation before the intention of the new theory was unification they wanted to understand
17:33
how electrons affect each other in other words it aim to explain how everything
17:39
works together through the electromagnetic fool they called their
17:44
unification project quantum electrodynamics or QED the project was a
17:51
formidable challenge but the end result was magnificent nothing less than the
17:58
most far-reaching and accurate scientific Leary ever conceived for
18:04
instance it predicts a certain property of the electron called its magnetic moment to have a value of two point zero
18:13
zero two three one nine three zero four
18:18
experiments measure precisely the same number that's an agreement between theory and experiments to one part in
18:26
ten billion it's an unprecedented level of agreement it's like measuring the distance between
18:32
London and New York to within the thickness of a human hair the phenomenal accuracy of quantum
18:39
electrodynamics shows it to underpin almost everything we experience in the
18:45
physical world it's as close to a theory of everything as we have ever come
18:51
it defines the laws of nature the atomic-scale it's explained shape color
18:57
texture and the way almost everything interacts and fits together it underpins
19:04
and encompasses everything from the biochemistry of life to why we don't fall through the floor so what does QED
19:13
actually say well this is where the going gets very tough it may be a
19:19
wonderful scientific description of nature but trying to understand what richard fineman was doing with his
19:25
theory is almost impossible this is what he himself said when he introduced his
19:31
theory to the public it is my task to convince you not to turn away because
19:37
you don't understand it you see my physics students don't understand it that's because I don't understand it
19:44
nobody does if the inventor of the theory doesn't
19:50
understand what possible hope is there for the rest of us with that disclaimer
19:56
I'm going to try and explain anyway first you have to abandon your most
20:02
basic intuition about nature you have to give up the notion that empty space is
20:07
empty let me try and explain if I were to suck out all the air from this jar
20:14
you'd quite rightly say that having removed all the atoms I'm left with a vacuum a volume of pure emptiness
20:23
quantum electrodynamics flies in the face of this common-sense idea by saying
20:28
that the vacuum is not a repeat not a place where nothing exists and nothing
20:34
happens instead it's full of stuff and is eating with activity how can this possibly be
20:44
true well let's imagine one tiny point
20:55
in the emptiness common sense tells us there's nothing there but quantum
21:00
physics tells us there's only nothing there on average and it's those two words on average that force us to
21:08
rethink our understanding of reality think of empty space like a bank account
21:13
which on average has nothing in it as a physics academic this is a concept I'm
21:18
very familiar with some days it might be a hundred pounds in credits other days it might be a hundred pounds overdrawn
21:23
but on average it has a zero balance empty space turns out to have similar
21:29
accounting skills but it can borrow energy rather than money and this energy
21:35
is literally borrowed from the future provided that is paid back again very quickly in practice what this means is
21:43
that the borrowed energy can be used to create a particle and an antiparticle which are spontaneously formed from the
21:50
void provided that a fraction of a second later they annihilate each other and disappear
21:59
energy is borrowed out of nowhere it's turned into matter the matter then self
22:05
destructs back into energy and this happens in an instant all over
22:13
the void in fact in a stunning confirmation of Dirac's antimatter theory the vacuum sees with huge numbers
22:22
of matter and antimatter particles continually being created and annihilated down at the smallest scale
22:38
space is a constant storm of creation and destruction physicists call it the
22:45
quantum foam the particles in the quantum foam come and go so quickly that
22:50
we're completely unaware of them we refer to them as virtual particles but
22:56
if we were able to slow time down almost to a standstill we'd be able to see this
23:02
seething activity this constant creation and annihilation of matter and energy
23:07
that's the fabric of reality itself and
23:13
from this comes the most jaw-dropping idea of all quantum electrodynamics says
23:20
that the matter we think of as the stuff that makes up the everyday world the world that we see in feel is basically
23:28
just to kind of leftover from all the feverish activity that virtual particles
23:33
get up to in the void so you me the earth the Stars everything is basically
23:40
just a part of a deep of course when
23:49
Fineman first started to develop his revolutionary ideas in Caltech in the mid 40s his contemporaries were
23:56
horrified because at that time the general opinion was that the quantum
24:01
electrodynamics project was an unmitigated gated disaster the theory couldn't be
24:08
solved the equations had no sensible solutions the mathematics had spiraled
24:13
out of control but Fineman believed that he could see a way through the mathematical complexity
24:19
to a new truth what firemen did with all the arrogance
24:27
and confidence of youth was slashed through the insanely complicated maths
24:33
Fineman developed a new series of revolutionary but almost childlike
24:38
diagrams to explain his new ideas their elegant simplicity flew in the face of
24:44
the complex maths of traditional quantum mechanics
24:51
conflict seemed inevitable then in 1948
24:58
at the age of 30 Richard Fineman decided to unveil his controversial version of
25:04
quantum electrodynamics with his idiosyncratic diagram to the physics
25:09
world and he chose the most important science all points of the American
25:14
calendar set on the coast of Pennsylvania the Shelter Island conference was a physics celebrity
25:21
service present were Niels Bohr the so-called father of atomic physics the
25:27
discoverer of antimatter Paul Dirac and the man behind America's atom bomb
25:33
robert Oppenheimer the atmosphere at the start of the conference was brittle
25:38
confidence in quantum electrodynamics was a bottom it seemed a hot mess
25:47
one after another the physicists stood up and droned on despairingly about how
25:52
they failed to find a solution then it was a turn of Richard Feinman barely
25:59
thirty years old he stood up and took his place in front of the world's most illustrious scientists and started to
26:05
unveil his new diagrams and equations what happened next was astonishing the
26:11
routes not so much over fine lands weird description of reality physicists were
26:17
used to weird by now but because he dared to visualize what was going on
26:22
instead of using arcane complicated mathematics Fineman was describing what
26:28
all his virtual particles are up to using his simple pictures there was
26:35
uproar Niels Bohr the father of quantum mechanics left from his chair and discussed he hated fineman's diagrams
26:43
because they weren't completely against everything he devoted his whole life to you see he believed that atomic
26:50
particles could not be visualized under any circumstances Fineman defended his
26:56
new theory trying to explain that the diagrams were simply a tool to help visualize his new equations but the rest
27:04
of the scientists including Paul Dirac wouldn't hear of it they called him an idiot who understood nothing about
27:11
quantum mechanics Fineman ended his lecture bruised but unrepentant he knew
27:19
that his diagrams and equations were correct if only he could convince the others
27:31
that evening firemen met another young physicist called julian schwinger now
27:38
Schwinger was the same age as fireman and had been identified as a child prodigy at the age of 12 although he and
27:45
fireman had been working independently and had approached a problem of quantum electrodynamics very differently they'd
27:52
reached identical conclusions with their new equations they could solve quantum
27:58
electrodynamics and with fireman's diagrams they produced a theory of
28:03
awesome power together now as allies they planned a full frontal attack on
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Niels Bohr in the Conservatives by the end of the conference the mood in the Pennsylvanian Roadhouse
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had changed from one of frustrated hopelessness to one of excitement and
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idealism over the next few years their theory was fleshed out and rapidly
28:28
became the most accurate and powerful theory mankind had ever had
28:39
despite finally being tamed quantum electrodynamics talk of empty space
28:45
seething with energy we can't feel and virtual particles we can't sing does
28:51
make many people including physicists a little suspicious and many skeptics
28:57
might say these ghostly objects that allegedly filled a vacuum aren't actually real yes the complicated
29:05
mathematical equations of quantum electrodynamics seem to require them but that doesn't itself mean they exist they
29:12
might just be mathematical fantasies with no basis in reality well I have bad
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news for the skeptics since the late 1950s direct evidence that empty space
29:28
isn't in the slightest bit empty but as in fact seething with activity has been
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observed time and time again in laboratories quantum electrodynamics is
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by any measure a truly magnificent discovery it's one great pinnacle of our
29:47
story a glorious conclusion to five amazing decades of science in quantum
29:54
electrodynamics the atom had given us a theory that explains much of our universe with stunning accuracy but
30:02
since quantum electrodynamics triumphant arrival in the late 40s our story
30:07
becomes rather messy and awkward as a result of quantum electrodynamics
30:14
scientists were convinced that the vast majority of everything in the universe consisted of essentially just two things
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atoms and light light was made out of tiny particles
30:28
called photons and atoms were made out of three components the electron in the
30:34
proton and the neutron and because of antimatter there were anti protons anti introns and
30:40
positrons a bit strange but pleasingly symmetrical everything in the physics
30:47
garden was Rosie thinks of the rules of quantum electrodynamics but then much of
30:54
the profound irritation of every working physicist a load of new and exotic
31:00
particles suddenly appeared like party gatecrashers to spoil the fun exotic entities that didn't fit into any
31:07
known theories were appearing in physics labs with such frequency the scientists
31:12
couldn't keep up with naming them all the neutrino the positive PI on the negative part the K on the lambda the
31:20
Delta and of course each of these had their antimatter counterparts when one
31:25
new particle named the muon was discovered one physicist quipped who ordered that the whole thing was a mess
31:33
that didn't make sense physicists despairingly refer to it as the particles ooh
31:40
it began to seem as though every time science has solved one of nature's mysteries the Aten would present them
31:48
with something even more weird within just a few years atomic physics had gone
31:54
from a position of quiet confidence to total chaos and of course to make some
32:01
sense of this new mystery would require yes you've guessed it another scientific
32:06
revolution the third genius in our story is Murray gell-mann gell-mann was a
32:14
child prodigy by the age of 15 he'd already started at Yale to study physics and had finished his PhD by his early
32:21
20s he had an incredible intelligence that terrified those around him he spoke
32:27
many languages and seemed to have this deep knowledge of any subject you care to throw at him like Richard Fineman
32:34
whom he joined here at Caltech in the early 60s he seemed to have this ability to see beyond the mathematics and the
32:40
formalism of his theories to the underlying secrets of nature below together Gelman and firemen made an
32:48
awesome duo this office number 456 used
32:53
to belong to Fineman what's great is that just two doors along the corridor was the office of Murray gell-mann there
33:01
was an intense academic rivalry between these two intellectual Giants but they fed off each other's creativity there
33:08
were very different personalities Fineman who played the buffoon gell-mann the cultured elitist young man used to
33:15
get upset by fireman's loud-voiced and firemen certainly enjoyed winding him up but as fair to say that during the 1960s
33:22
and 70s these two geniuses here at Caltech dominated the world of particle
33:28
physics their bitter rivalry pushed them both to
33:36
the very limits of their imaginations and gell-mann especially was desperate
33:41
to prove himself over Fineman by bringing some order into the particle zoo within the feverishly intellectual
33:51
atmosphere of Caltech gal man's mind did something very strange he started
33:57
working with a different kind of mathematics to deal with the preponderance of subatomic particles
34:03
he used an obscure form of maths called group theory as its name suggests this
34:09
is a theory that analyzes groups of numbers and symbols and tries to organize them into simple patterns and
34:16
symmetries it's a bit like working with an abstract form of origami using this
34:22
technique gell-mann started working all known particles into an organized system
34:27
which he called the Eightfold way after a Buddhist poem but then he had his most
34:34
awesome revelation Gelman realized that his group theory pointed to a new deeper
34:40
underlying mathematical truth something which had the potential of rewriting the
34:45
atomic rulebook
34:50
what girl mans mathematics revealed to him was that in order to make coherent
34:56
patterns of all the new particles in his Eightfold way he had to acknowledge that
35:02
there was a deeper underlying fundamental reality once again it turned
35:07
out that things were not at all as they seemed
35:13
you see physicists had been comfortable with the notion that atoms are made up of three different kinds of particles
35:19
electrons orbiting around the outside of a nucleus itself made up of protons and
35:25
neutrons young man had the temerity to suggest that protons and neutrons were
35:30
themselves composed of more elementary particles particles that he called
35:35
quarks
35:43
Murray gell-mann was cultured and arrogant but a heart lacked confidence
35:49
he knew that for his colleagues even those used to the strangeness of the
35:54
atom quarks were a step too far and in any case there'd been no evidence
36:00
of anything remotely like a quad he was convinced his new theory will be
36:05
declared outlandish or just wrong so gell-mann sat on his revelation and
36:12
one of the greatest ideas in science was almost lost forever then something
36:21
extraordinary turned up just a few hundred miles north of his office
36:35
this is the Stanford Linear Accelerator a few miles south of San Francisco or
36:40
you can see below me is one end of what is basically a giant electron gun a beam
36:46
of high-energy electrons is fired through a tunnel that starts off over two miles away in the hills travels
36:54
underneath the freeway and comes out at this end where it enters the experimental area the gray building over
37:00
there is called M station a and is where one of the most important discoveries and physics was made it was built during
37:07
the 1960s when it was and still is today the longest single building on earth and
37:13
although it's 40 years old you can see a lot of construction workers going on now is still being used for fundamental
37:20
research today [Music]
37:28
I'm now inside the two-mile-long linear accelerator building the red objects you
37:34
see on your right our pod colostrums and they provide the power that boosts the electron beam that runs 20 feet
37:40
beneath us such as the acceleration these electrons will within the first few meters have reached 99% the speed of
37:49
light let me put it another way if these electrons were to start off their journey at the same time that you fire a
37:56
bullet from a gun they would have covered the full two-mile distance before the bullet has even left the
38:03
barrier the electron beam now traveling
38:09
up almost the speed of light would have arrived here at the target area there would have been in 1968 where I'm
38:15
standing now a large tank of hydrogen basically protons the electrons would
38:21
smash into the protons and scatter off through tubes to be picked up by huge
38:26
detectors that filled the hall outside [Music]
38:39
and as they did this physicists got their biggest ever confirmation that
38:44
there might be a deeper set of rules underpinning the particles ooh
38:52
while they're discovered from the way the electrons scattered and because of their extremely high energy was
38:59
conclusive proof that a protons had internal structure in other words
39:04
protons were themselves made of more elementary particles here were
39:10
gell-mann's quarks this was an astonishing moment for decades people
39:17
were confident that the components of the atomic nucleus the proton and neutron were absolutely fundamental and
39:25
now for the first time there was evidence of something deeper
39:33
[Music] the quark is a tricky and elusive beast
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there are six different kinds or flavors of quark up down strange charm top and
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bottom also quarks never exist in isolation only in combination with other
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quarks this makes it impossible to see directly we can only infer their presence but despite these caveats the
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quark brought some semblance of order to the particles ooh in recent years is
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allowing us to concoct a simple yet powerful description of how the universe
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is built up basically everything in the universe made of atoms is built up from
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just quarks and electrons that's it this
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now brings us pretty well right up to date the discovery of the quark in 1967
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was the last significant experimental discovery of a new type of fundamental
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particle some say we may yet discover that quark is made of something even stranger and
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is possible but for now it's as good as it gets
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our journey from Einsteins proof of the existence of atoms in 1905 until now has
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been extraordinary we've learned so much about the atomic world from the size and
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shape of the atom to how its center hold the secret of the universe itself from
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how it reveals an unknown world of antimatter to how empty space is far from empty from what we thought was a
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basic building block of the universe itself to the discovery of something even more fundamental inside it and yet
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despite all the powerful science which we've uncovered something doesn't quite add up there were two startling and
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worrying and nominees the first of these is now at the forefront of theoretical physics across
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the world and it concerns one of the oldest scientific principles there is
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gravity now though gravity has been thoroughly understood since Einstein it's never really been part of atomic
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theory until now suddenly there's a glimmer of hope from ideas that sound
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almost too crazy to be possible some of these are called string theories that
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regard all subatomic particles as tiny vibrating strings that have higher
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dimensions of space trapped inside them some called brain theories suggest our
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entire space and time is just a membrane floating through the multiverse another
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called Quantum loop gravity suggests that nothing really exists at all and
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that everything is ultimately made up of tiny loops in space and time themselves
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but despite gravity's unwillingness to fit in with quantum theory I believe
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there's something worse lurking in the quantum shadows something truly nightmarish late into the night at
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physics conferences all over the world over drinks at the bar when we scientists huddled together to debate
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and discuss our strangest ideas and dreams there are still things that really really bother us and chief among
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these are the quantum mechanical laws that atoms obey and in particular one aspect of these laws something called
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the measurement problem if you want to see fear in a quantum physicists eyes
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just mention the words the measurement problem the measurement problem is this
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an atom only appears in a particular place if you measure it in other words
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an atom is spread out all over the place until a conscious observer decides to
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look at it so the act of measurement or observation creates the entire universe
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and just to show you how mad this idea is I'm going to explain one of them
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famous hypothetical experiments in the whole of science it's called the
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Schrodinger's cats experiment early Schrodinger was one of the founding fathers of atomic theory and in the mid
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1930s devised a thought experiment purely to highlight the absurdity of
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quantum mechanics he suggested you take a box in which you place an unopened
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container of cyanide connected to a radiation detector and some radioactive
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material now the idea is that if an atom in the material emits a particle this
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will be picked up by the detector which in turn releases the cyanide next you
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take Schrodinger's cat which in this case is a lovely Norwegian Forest cats called Dawkins now I shall point out
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that this isn't real cyanide you place the cat in the box you close the lid and
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wait so here's the conundrum according
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to traditional quantum mechanics known as the Copenhagen interpretation all the
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time the box is closed the radioactive atom inside has yet to make up its mind
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whether it is decayed and spat out a particle so we have to describe it as
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both having decayed and not decayed at the same time think about what this
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means since the radioactive particle triggers the release of the poison the cat is
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both poisoned and not poisoned so until we open the lid to check up on the fate
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of the cat what's called making a measurement it's not just that we don't know whether the cat is literally both
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dead and alive at the same time this is clearly a paradox or is it
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the paradox of Schrodinger's cat and the contradictory nature of the measurement
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problem really does force us to accept the tiny objects down at the atomic
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scale but Bay their own set of profoundly strange rules but at larger
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scales those of everyday human experience those rules vanish and an
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utterly new set of nice intuitive rules take over how can this be some argue
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that in fact the quantum weirdness of the atom might actually be writ large across the cosmos that we may have to
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rethink everything we knew about the universe [Music]
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in the last 100 years we have peered deep inside the atom the basic building
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block of the universe and inside this tiny object we have found a strange new
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world governed by exotic laws that at times seem to defy reason atoms present
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us with dizzying contradictions they can behave both as particles or waves they
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appear to be in more than one place at the same time they force us to rethink what we mean by past and future by cause
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and effect and they tell us strange things about where the universe came from and where it's going pretty amazing
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stuff for something that's just a millionth of a millimetre across that's
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why Niels Bohr the father of atomic physics once said that when it comes to
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atoms language can only be used as poetry what's fascinating to me is that
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although we've learnt an incredible amount about atoms in their behavior our scientific journey has only just begun
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because although we know how a single atom or just a few atoms behave the way
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trillions of them come together in concert to create the world around us it's still largely a mystery to give you
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one dramatic example the atoms that make up my body are identical to the atoms in
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the rock the trees the air even the stars and yet they come together to
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create a conscious being who can ask the question what is an atom explaining all
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that is surely the next great challenge in science
Human Consciousness of Fractals What are the intricacies involved in the human consciousness of fractals? The human consciousness of fractals involves the perception and interpretation of complex patterns and shapes that repeat on multiple scales. Fractals are often visually appealing to people, and they have been used in a variety of artistic, architectural, and scientific applications. In terms of perception, the human visual system is well-suited to recognizing fractal patterns. This is because fractals tend to have self-similar features that repeat on multiple scales, and the human visual system is adept at detecting patterns and recognizing similarities. This makes fractals a natural fit for human visual perception, and it is likely that our brains are wired to recognize and respond to fractals in certain ways. In terms of interpretation, people often associate fractals with concepts like chaos, unpredictability, and complexity. This is because fractals can be used to model comple...
The Beautiful Structure of Cosmic Nothingness: Understanding Immutability. - https://medium.com/@najmanhussain/the-beautiful-structure-of-cosmic-nothingness-understanding-immutability-b54e7747da6b I hope that this write-up is appealing to the imagination. It is not intended to be rigorous.. Since time immemorial, humans have wondered what life on earth was all about. They would not have missed the fact that not all patterns are exhibited in the natural world. Only certain shapes are exhibited in the realm of nature and these are beautiful. In the last couple of decades, we have deepened our knowledge to include fractal geometry. “A fractal is a never-ending pattern..They are created by repeating a simple process over and over in an ongoing feedback loop. Driven by recursion, fractals are images of dynamic systems..” What are Fractals? — https://fractalfoundation.org/resources/what-are-fractals/ I came across fractals only lately, well after I went into retirement. Briefly, fractals are...
Hyperbolic geometry is a type of non-Euclidean geometry that differs from classical Euclidean geometry in its treatment of parallel lines. In Euclidean geometry, parallel lines are equidistant and will never meet. In hyperbolic geometry, parallel lines can get arbitrarily close but will never intersect. Hyperbolic geometry is characterized by a constant negative curvature, meaning that lines curve away from each other, and objects in hyperbolic space appear to be "slimmer" than in Euclidean space. This leads to counterintuitive results, such as the fact that in hyperbolic geometry, there are more parallel lines to a given line through a point than there are in Euclidean geometry. Hyperbolic geometry has important applications in many areas of mathematics, including number theory, cryptography, and the study of Riemann surfaces. It is also used in physics to model the behavior of certain physical systems, such as the geometry of space-time in general relativity.
