I am a theoretical physicist so my
speech will be significantly
different from the previous and yet
you’ll see that maybe you
will find some similarities
it’s a bit of a surprise for me but
you’ll see I specialize in
Theoretical Physics in Physics
fundamental and I wondered in
How this discipline that we
talk about the reality of the world but
the reality of the world that is that
space time the material
the glide light etcetera and
notions that ultimately are reached
a pretty hard way with
experiences comments very
delicate and that is why we talk
because of fundamental physics
These are fundamental questions is
very difficult to tackle
and I wondered how
the discipline could we measure
help and guide us in our lives
in our personal lives of all
days and I got several
answers and I have chosen for a
You talk about this evening there
others there are others such
unique and very interesting is to
question the creativity of these
Scientists have given us
remarkable results as einstein
or Newton Galilee and many others and
This is extremely interesting
extremely rewarding and when
wonders about the reasons for this
creativity
oh of course there is no miracle
no easy answers but
include some of the aspects that
just heard but that’s another
This is another aspect that I want
discuss tonight is the lesson I
would pull it finally he
Beware of our intuition it
to regain what has been said all
on time
beware of our first impressions
so it’s not quite in
hands
circumstances it is not so
meetings with colleagues or
people that it is necessary to
attend but beware of
impressions generally
and when we want to understand what is
happening around us and why
I chose an example that will be
drawn from the fundamental physics
which is a general relativity
theory which of course you you
have heard and do
know maybe not all his
details and I’ll say a few
words
I could also choose another
branch of theoretical physics
called quantum physics is
full of surprises but also so
I chose tonight relativity
general and more precise theme
is that of temporal concepts and you
will see that general relativity
we send a message that is very
clear is that time does not exist and
But time is something
we handle all the days
allows us to get together to
give appointments we
use constantly in our
practice in all aspects of our
life
yet the physics teaches us
that time does not exist and I would
to an accuracy which is also very
important because sometimes and I
even I have to tell you
the relativity theory
General relativity tells us that
time does not exist, but in fact it is
not exactly it is that it is
observing the very specific world
by physicists by their experience
by observations that teaches us
that time does not exist and it is
then general relativity by
means Dalsh einstein which
was the creator is that einstein
this theory gives us a
interpretation of the world that holds
of this fact established that the time
does not exist, ie it is not the
General relativity or anyone
any theory that will tell you
specifically the time does not exist
but observing the world
experimentation on the world
research that are physicists
practical and concrete way that we
said the world as we discovered is
incompatible with the existence of time
and then general relativity
built by einstein will give us
a description of the world that takes into
account this fact but which I repeat is
an observation that infects
experience time does not exist and
why I chose this topic because if
that obviously the existence of time
is so and so permeates our
music our lives is a
thing we had the intuition
it is something that seems
Obviously time is obviously one
wants to say well not yet
observing the world we itch
then to start before returning
in the subject of relativity
General
I just want to expose you
result of very specific experiences
I could have chosen much but I
will give you one that is very
specific has been done there
few years and that will illustrate the
that time does not exist that you
will give an experimentation if
you want concrete
so this is the most clocks
accurate than men, and never
built they are atomic clocks
they are very atomic clocks
very complicated systems
called complicated in this case
particular optical fountains
reasons I’m not going
explain here and these clocks are
highly accurate, ie if
you have a watch, and your watch
not going to say ahead of a second
delayed one second in one year
you’ll be good enough I think
satisfied I never have a watch
as accurate and indeed the good
clocks which I speak can
be sure that the 13 billion
years of existence of the universe they
do not advance or does not delay more
a second
so this is the most accurate lose that
it has never been able to build and it is
even hard to imagine better
good then physicists have built
clocks like that and if you
let one beside the other and
although they are perfectly
synchronized
when you put in the time you
the course set at the same time
and always always always shows
the same time as it remains one
next to each other but you take
One of these clocks and then you
slowly bring to the stepped in
above the building you let
a time on the floor above and then
and you go down and when you
down the well and its indication
no longer coincides with the indication
the other clock, so that these are two
perfect clocks
then of course they will not be
a second offset a minute
but a small fraction seconds but
that their accuracy can measure
means what it means everything
just as there is one thing that is
sure is that since both
clocks worked perfectly
and since it gives results
different if time is there
at least one of the two that does not give
the time they do not measure time
and if you take 10 clock
different as you make them
different paths in the building
again this is something that
was achieved simply by mounting
the clock to the stepped above
few meters higher you
10 with the result of the clock
different with its clock without
result different and there is no
reason to think that is one that
shows the time and the other
indicate anything other then
could imagine several time ago
there is the time indicated number
the number one clock time number 2
but at this time and there you go
being forced to imagine that time
and two
if you have 10 clock there are 10 if
each with its clock
ago how 7 billion people
on earth there will be 7 billion times
different etc. etc.
there is no limit so it is
impossible to imagine the time and 7
billion facets like that and
ultimately the only way to get
out and this is what the
physicists and it was confirmed by
of other types experience that I have
no time to expose this evening but
ultimately the only coherent vision of
world is to tell the time there
not so what measures a
clock and many a measurement clock
finally a term that is not at all
the same thing is to say the clock
measures the time that elapses from the
when it is put on time
until we go and lyre
ultimately the message we
from this experiment is that
between two specific times and well
two clocks two people will
measure will go live experience
different durations
paul langevin physicist who was a
einstein of friends in the years
1920 and was the first to
I understand general relativity
imagined a little experience
thinking in this kind of experience
twins twins who
Obviously when it comes to the same snes
where and are the same age and then
the twins will at some point
from a journey in space and
find his twin brother and well
they have the same age at the point of
starting when they say
kiss before the twin
Travelers ride in his ship
spatial and when back when
find themselves well there was one who
lived eg 20 years and the other
lived fifty years so they will
up in the situation where two
twins who obviously had initially
the same age, well there is one that
will be 40 years old and the other 70 years
good this is something that has never
was made for reasons
practical because it would require the
Twin travelers will take a trip
very fast with a rocket that the
subject to an acceleration which
would be unsustainable
but if you want it is a
transcript on our scale of this
experience clock was
realized and therefore the conclusion
again it is that time does
can not exist because each of
twins could say – the duration
I experienced it is a measure of the time
and as they are different it may
not be a single time for all
world and that therefore it is the message of the
relativity and this relativity
where does she know it’s you
a creation of the son
a brilliant named albert
einstein and to say two good words
Albert Einstein was born in 1889 and
1879 and forgiveness in 1905
stein while Anne was employed in
a patent office when he
had never been in universities
then he had never been in contact
with the faculty with teaching
Higher University he wrote
in this 1905 three articles
which each have three in a manner
different revolutionized physics
while it was not a
researcher professionals as there
had at the time and as there
has even more today
so that was one of the great mysteries
how this young man outside
circuits may have three ideas as
great course the historians
Psychologists everyone is interested
much to it but I will leave
side tonight but among these three
Articles there is one that considers
as the foundation of physics
Quantum another one considers
as confirming that which had
really need at the time of what
called the atomic hypothesis
ie the design of the
material which is made of carbon which
is our concept today is the
third article based this
theory of relativity
because Einstein discovered this
fundamental thing that time does not exist
no he did not discover the way
I have previously indicated
because the experiences I you
have mentioned that they have made it
a few years ago was not at all
within reach of technology
then he discovered another
by way of questions
Synchronicity I’m not you
explain here but have been analyzed
course by physicists that
explains in relativity courses
which have been analyzed by the
historians because as Einstein’s
he came to all this is good
Also extremely interesting
but what is interesting is that
what Einstein found the first
is that the notion simultaneity
can not exist
Then imagine that you have a friend
colleague and cosmonauts and that
found on the planet Mars and you
want to ask you to
the exact moment when I
speaks what my friend is
to the planet Mars
at the precise moment when I speak good
bah you can ask him
have the soul is that if you ask me
issue wanted to send a message by
example by radio the message 28 minutes
So after eight minutes it will
receive the question what you’re
doing it will say I’m
Train uncap bottle
beer
but when you receive
reply eight minutes it will still
elapsed so it will be widely bus
beer and anyway you will
we do not have the answer to it
was when you sent
the message
so there is a communication problem
how to know how to synchronize
my colleague from the planet Mars
that when I speak and einstein
was well aware that there
a difficulty
then this difficulty he tried to
the resolve
he tried to say is what is
could imagine a procedure that will
necessarily be more complicated than this
exchange of signals I have
mention is what might
imagine a procedure to me
know what my friend now
eg I a capsule
bottle of beer
good he envisioned a process like this
where everyone started
okay well I apply this process
which is a bit complicated but which is
quite feasible in practice and
I concluded
while I my bottle caps
Beer my friend on Mars is also
train uncap the bottle
Beer the problem is that if my friend
on Mars is doing
exactly the same as me
and wonder what makes the
when it caps the bottle
beer he will find that I am
just finishing the video is
impossible to get
agree and there is no way on
simultaneity concept that is me
I think that homo eats
my bottle caps
my friend capsules him his bottle
he will think when Gilles
capsules the bottle
I’ve almost finished my beer and
there is no way to get
Okay
so it is impossible to
simultaneity and it is also a
inability of the time because if the
Time was when such could
said
it is now 20 hours in any
the universe
the concept of simultaneity it would
very well defined simply tell
the other looks at your watch that says
time if time and say it was indicated
me what you did to 20h and I
know what I did in 20 hours I
capsules and my good beer in this
If there could agree
on a response
so if you want the impossibility of
to agree on a response that
was found by einstein well that
confirmed multiple ways
since tells us that not only
concept of simultaneity does not exist
but the concept of time can not
to exist
However the notion of time exists
perfectly what extent a clock
again it is the time that
has elapsed for this clock
accurate from when making
time is finally that
two clocks living two
different stories
because one has a nursing age
over the periods do not coincide
it surprises us that of course we
prevented from doing what we do
usually that is to say it
takes all times coinciding
everything is to say the time it’s called
Now it is hard and
coincide well can be more
call this time in life
course as the current
differences which I speak is
microseconds who cares
completely
and therefore what we call this time
is that all the times that
we live by example between the time
As we enter this room and
time we go out we live
each different durations but
different from a second fraction of
So it is as if they were
same periods
So let’s say we all had the same
time we call that time and
everyday
it works very well but we know
Now we know with physics
particles that go very fast with
cosmic rays with
astrophysics with navigation
Space with telecommunications
space with the GPS system through
all that millions and millions of
times each day it is checked that the
Time does not exist and can not
to exist
then what consequences in life
everyday and I’ll end up there
good the first is that I like so
wanted to say beware of its
intuitions of our intuition that we
said obviously swinging it exists
beware of first impressions
and
also mean about ourselves
what we ourselves
what is my friend cosmonauts
because I can not think of my
Friend cosmonauts at the moment
because I do not know what it does
at the moment and I have no
way of knowing I have to think
my friend as someone cosmonauts
who lives a story that lives a
history of its past with its present
with his future that describes a story
and myself who am I
if I want to define myself I’m not
only one who speaks in you
now I’m the one who took the train
just now I’m single incident
technical
it’s okay I’m the one who made
she traveled there a few times that
wrote a book that met so and so
and-so I’m the one that will also
take the train tomorrow that will do
Such other travel so if i want to
define myself I do not define myself
as I am one moment to moment
present
but I define what I call my
world line that is the
continuity of all the events
I experienced my birth and my death
this is me and if I want to know who
you are well there is not enough
you observe in this famous tenth
second which is previously talked
because I would have felt
biased but I need to know that
you are from the beginning must
I know your world line
ie you are not a
point in space at a given time
but you are a line and that line
it is not in space but
is in what is called the spacetime
and so eventually this message
seems fundamental message
relatively abstract of these theories
of relativity is not telling us
does not live in the space and
but emptying time something
more complicated what time space I
and now not going to define what
it is that space-time but
finally it applies as I think
our life everyday and
Perhaps we need a hall and
little against our intuition that is
what exists namely myself
ourselves but also yourself
any object an object that is not
something that is a given time
in
happens but it’s something that
is a history in time and space
So if we want to understand the reality
of the world
it is better to speak in history that
place that is not in place
time but in space-time because
time if we want to be strict
there are more and therefore we are all
stories all the objects we
meet that we meet are
stories and so I think our
worldview both physical
Fundamental physics must draw
fundamental and say that we live
unlike in a time space
Perhaps our intuition
thank you
[Applause]
speech will be significantly
different from the previous and yet
you’ll see that maybe you
will find some similarities
it’s a bit of a surprise for me but
you’ll see I specialize in
Theoretical Physics in Physics
fundamental and I wondered in
How this discipline that we
talk about the reality of the world but
the reality of the world that is that
space time the material
the glide light etcetera and
notions that ultimately are reached
a pretty hard way with
experiences comments very
delicate and that is why we talk
because of fundamental physics
These are fundamental questions is
very difficult to tackle
and I wondered how
the discipline could we measure
help and guide us in our lives
in our personal lives of all
days and I got several
answers and I have chosen for a
You talk about this evening there
others there are others such
unique and very interesting is to
question the creativity of these
Scientists have given us
remarkable results as einstein
or Newton Galilee and many others and
This is extremely interesting
extremely rewarding and when
wonders about the reasons for this
creativity
oh of course there is no miracle
no easy answers but
include some of the aspects that
just heard but that’s another
This is another aspect that I want
discuss tonight is the lesson I
would pull it finally he
Beware of our intuition it
to regain what has been said all
on time
beware of our first impressions
so it’s not quite in
hands
circumstances it is not so
meetings with colleagues or
people that it is necessary to
attend but beware of
impressions generally
and when we want to understand what is
happening around us and why
I chose an example that will be
drawn from the fundamental physics
which is a general relativity
theory which of course you you
have heard and do
know maybe not all his
details and I’ll say a few
words
I could also choose another
branch of theoretical physics
called quantum physics is
full of surprises but also so
I chose tonight relativity
general and more precise theme
is that of temporal concepts and you
will see that general relativity
we send a message that is very
clear is that time does not exist and
But time is something
we handle all the days
allows us to get together to
give appointments we
use constantly in our
practice in all aspects of our
life
yet the physics teaches us
that time does not exist and I would
to an accuracy which is also very
important because sometimes and I
even I have to tell you
the relativity theory
General relativity tells us that
time does not exist, but in fact it is
not exactly it is that it is
observing the very specific world
by physicists by their experience
by observations that teaches us
that time does not exist and it is
then general relativity by
means Dalsh einstein which
was the creator is that einstein
this theory gives us a
interpretation of the world that holds
of this fact established that the time
does not exist, ie it is not the
General relativity or anyone
any theory that will tell you
specifically the time does not exist
but observing the world
experimentation on the world
research that are physicists
practical and concrete way that we
said the world as we discovered is
incompatible with the existence of time
and then general relativity
built by einstein will give us
a description of the world that takes into
account this fact but which I repeat is
an observation that infects
experience time does not exist and
why I chose this topic because if
that obviously the existence of time
is so and so permeates our
music our lives is a
thing we had the intuition
it is something that seems
Obviously time is obviously one
wants to say well not yet
observing the world we itch
then to start before returning
in the subject of relativity
General
I just want to expose you
result of very specific experiences
I could have chosen much but I
will give you one that is very
specific has been done there
few years and that will illustrate the
that time does not exist that you
will give an experimentation if
you want concrete
so this is the most clocks
accurate than men, and never
built they are atomic clocks
they are very atomic clocks
very complicated systems
called complicated in this case
particular optical fountains
reasons I’m not going
explain here and these clocks are
highly accurate, ie if
you have a watch, and your watch
not going to say ahead of a second
delayed one second in one year
you’ll be good enough I think
satisfied I never have a watch
as accurate and indeed the good
clocks which I speak can
be sure that the 13 billion
years of existence of the universe they
do not advance or does not delay more
a second
so this is the most accurate lose that
it has never been able to build and it is
even hard to imagine better
good then physicists have built
clocks like that and if you
let one beside the other and
although they are perfectly
synchronized
when you put in the time you
the course set at the same time
and always always always shows
the same time as it remains one
next to each other but you take
One of these clocks and then you
slowly bring to the stepped in
above the building you let
a time on the floor above and then
and you go down and when you
down the well and its indication
no longer coincides with the indication
the other clock, so that these are two
perfect clocks
then of course they will not be
a second offset a minute
but a small fraction seconds but
that their accuracy can measure
means what it means everything
just as there is one thing that is
sure is that since both
clocks worked perfectly
and since it gives results
different if time is there
at least one of the two that does not give
the time they do not measure time
and if you take 10 clock
different as you make them
different paths in the building
again this is something that
was achieved simply by mounting
the clock to the stepped above
few meters higher you
10 with the result of the clock
different with its clock without
result different and there is no
reason to think that is one that
shows the time and the other
indicate anything other then
could imagine several time ago
there is the time indicated number
the number one clock time number 2
but at this time and there you go
being forced to imagine that time
and two
if you have 10 clock there are 10 if
each with its clock
ago how 7 billion people
on earth there will be 7 billion times
different etc. etc.
there is no limit so it is
impossible to imagine the time and 7
billion facets like that and
ultimately the only way to get
out and this is what the
physicists and it was confirmed by
of other types experience that I have
no time to expose this evening but
ultimately the only coherent vision of
world is to tell the time there
not so what measures a
clock and many a measurement clock
finally a term that is not at all
the same thing is to say the clock
measures the time that elapses from the
when it is put on time
until we go and lyre
ultimately the message we
from this experiment is that
between two specific times and well
two clocks two people will
measure will go live experience
different durations
paul langevin physicist who was a
einstein of friends in the years
1920 and was the first to
I understand general relativity
imagined a little experience
thinking in this kind of experience
twins twins who
Obviously when it comes to the same snes
where and are the same age and then
the twins will at some point
from a journey in space and
find his twin brother and well
they have the same age at the point of
starting when they say
kiss before the twin
Travelers ride in his ship
spatial and when back when
find themselves well there was one who
lived eg 20 years and the other
lived fifty years so they will
up in the situation where two
twins who obviously had initially
the same age, well there is one that
will be 40 years old and the other 70 years
good this is something that has never
was made for reasons
practical because it would require the
Twin travelers will take a trip
very fast with a rocket that the
subject to an acceleration which
would be unsustainable
but if you want it is a
transcript on our scale of this
experience clock was
realized and therefore the conclusion
again it is that time does
can not exist because each of
twins could say – the duration
I experienced it is a measure of the time
and as they are different it may
not be a single time for all
world and that therefore it is the message of the
relativity and this relativity
where does she know it’s you
a creation of the son
a brilliant named albert
einstein and to say two good words
Albert Einstein was born in 1889 and
1879 and forgiveness in 1905
stein while Anne was employed in
a patent office when he
had never been in universities
then he had never been in contact
with the faculty with teaching
Higher University he wrote
in this 1905 three articles
which each have three in a manner
different revolutionized physics
while it was not a
researcher professionals as there
had at the time and as there
has even more today
so that was one of the great mysteries
how this young man outside
circuits may have three ideas as
great course the historians
Psychologists everyone is interested
much to it but I will leave
side tonight but among these three
Articles there is one that considers
as the foundation of physics
Quantum another one considers
as confirming that which had
really need at the time of what
called the atomic hypothesis
ie the design of the
material which is made of carbon which
is our concept today is the
third article based this
theory of relativity
because Einstein discovered this
fundamental thing that time does not exist
no he did not discover the way
I have previously indicated
because the experiences I you
have mentioned that they have made it
a few years ago was not at all
within reach of technology
then he discovered another
by way of questions
Synchronicity I’m not you
explain here but have been analyzed
course by physicists that
explains in relativity courses
which have been analyzed by the
historians because as Einstein’s
he came to all this is good
Also extremely interesting
but what is interesting is that
what Einstein found the first
is that the notion simultaneity
can not exist
Then imagine that you have a friend
colleague and cosmonauts and that
found on the planet Mars and you
want to ask you to
the exact moment when I
speaks what my friend is
to the planet Mars
at the precise moment when I speak good
bah you can ask him
have the soul is that if you ask me
issue wanted to send a message by
example by radio the message 28 minutes
So after eight minutes it will
receive the question what you’re
doing it will say I’m
Train uncap bottle
beer
but when you receive
reply eight minutes it will still
elapsed so it will be widely bus
beer and anyway you will
we do not have the answer to it
was when you sent
the message
so there is a communication problem
how to know how to synchronize
my colleague from the planet Mars
that when I speak and einstein
was well aware that there
a difficulty
then this difficulty he tried to
the resolve
he tried to say is what is
could imagine a procedure that will
necessarily be more complicated than this
exchange of signals I have
mention is what might
imagine a procedure to me
know what my friend now
eg I a capsule
bottle of beer
good he envisioned a process like this
where everyone started
okay well I apply this process
which is a bit complicated but which is
quite feasible in practice and
I concluded
while I my bottle caps
Beer my friend on Mars is also
train uncap the bottle
Beer the problem is that if my friend
on Mars is doing
exactly the same as me
and wonder what makes the
when it caps the bottle
beer he will find that I am
just finishing the video is
impossible to get
agree and there is no way on
simultaneity concept that is me
I think that homo eats
my bottle caps
my friend capsules him his bottle
he will think when Gilles
capsules the bottle
I’ve almost finished my beer and
there is no way to get
Okay
so it is impossible to
simultaneity and it is also a
inability of the time because if the
Time was when such could
said
it is now 20 hours in any
the universe
the concept of simultaneity it would
very well defined simply tell
the other looks at your watch that says
time if time and say it was indicated
me what you did to 20h and I
know what I did in 20 hours I
capsules and my good beer in this
If there could agree
on a response
so if you want the impossibility of
to agree on a response that
was found by einstein well that
confirmed multiple ways
since tells us that not only
concept of simultaneity does not exist
but the concept of time can not
to exist
However the notion of time exists
perfectly what extent a clock
again it is the time that
has elapsed for this clock
accurate from when making
time is finally that
two clocks living two
different stories
because one has a nursing age
over the periods do not coincide
it surprises us that of course we
prevented from doing what we do
usually that is to say it
takes all times coinciding
everything is to say the time it’s called
Now it is hard and
coincide well can be more
call this time in life
course as the current
differences which I speak is
microseconds who cares
completely
and therefore what we call this time
is that all the times that
we live by example between the time
As we enter this room and
time we go out we live
each different durations but
different from a second fraction of
So it is as if they were
same periods
So let’s say we all had the same
time we call that time and
everyday
it works very well but we know
Now we know with physics
particles that go very fast with
cosmic rays with
astrophysics with navigation
Space with telecommunications
space with the GPS system through
all that millions and millions of
times each day it is checked that the
Time does not exist and can not
to exist
then what consequences in life
everyday and I’ll end up there
good the first is that I like so
wanted to say beware of its
intuitions of our intuition that we
said obviously swinging it exists
beware of first impressions
and
also mean about ourselves
what we ourselves
what is my friend cosmonauts
because I can not think of my
Friend cosmonauts at the moment
because I do not know what it does
at the moment and I have no
way of knowing I have to think
my friend as someone cosmonauts
who lives a story that lives a
history of its past with its present
with his future that describes a story
and myself who am I
if I want to define myself I’m not
only one who speaks in you
now I’m the one who took the train
just now I’m single incident
technical
it’s okay I’m the one who made
she traveled there a few times that
wrote a book that met so and so
and-so I’m the one that will also
take the train tomorrow that will do
Such other travel so if i want to
define myself I do not define myself
as I am one moment to moment
present
but I define what I call my
world line that is the
continuity of all the events
I experienced my birth and my death
this is me and if I want to know who
you are well there is not enough
you observe in this famous tenth
second which is previously talked
because I would have felt
biased but I need to know that
you are from the beginning must
I know your world line
ie you are not a
point in space at a given time
but you are a line and that line
it is not in space but
is in what is called the spacetime
and so eventually this message
seems fundamental message
relatively abstract of these theories
of relativity is not telling us
does not live in the space and
but emptying time something
more complicated what time space I
and now not going to define what
it is that space-time but
finally it applies as I think
our life everyday and
Perhaps we need a hall and
little against our intuition that is
what exists namely myself
ourselves but also yourself
any object an object that is not
something that is a given time
in
happens but it’s something that
is a history in time and space
So if we want to understand the reality
of the world
it is better to speak in history that
place that is not in place
time but in space-time because
time if we want to be strict
there are more and therefore we are all
stories all the objects we
meet that we meet are
stories and so I think our
worldview both physical
Fundamental physics must draw
fundamental and say that we live
unlike in a time space
Perhaps our intuition
thank you
[Applause]
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