-
One of the most remarkable aspects
of the human brain
-
is its ability to recognize patterns
and describe them.
-
Among the hardest patterns
we've tried to undestand
-
is the concept of
turbulent flow in fluid dynamics.
-
The German physicist
Verner Heisenberg said,
-
"When I meet God, I'm going to ask him
two questions:
-
why relativity and why turbulence?
-
I really believe he will have
an answer for the first."
-
As difficult as turbulence is to
understand mathematically,
-
we can use art to depict the way it looks.
-
In June 1889, Vincent Van Gogh painted
the view just before sunrise
-
from the window of his room at the
Saint Paul de Mausole Asylumn
-
in Saint-Rémy-de-Provence,
-
where he'd admitted himself after
mutilating his own ear
-
in a psychotic episode.
-
In the Starry Night,
his circular brush strokes
-
creates a night sky filled with
swirling clouds and eddies of stars.
-
Van Gogh and other impressionists
represented light in a different way
-
than their predecessors,
seeming to capture its motion,
-
for instance, across sun dappled waters,
-
or here in star light that
twinkles and melts
-
through milky waves of blue night sky.
-
The effect is caused my luminance,
-
the intensity of the light in the colors
on the canvas.
-
The more primitive part of our
visual cortex,
-
which sees light contrast and motion,
but not color,
-
will blend two differently
colored areas together
-
if they have the same luminance.
-
But our brains primate
subdivision
-
will see the contrasting colors
without blending.
-
With these two interpretations
happening at once,
-
the light in many impressionist works
seems to pulse, flicker and radiate oddly.
-
That's how this and other impressionist
works use quickly executted
-
prominent brush strokes to capture
something strikingly real
-
about how light moves.
-
60 years later, Russian mathematician
Andrey Kolmogorov,
-
furthered our mathematical
understanding of turbulence
-
when he proposed that energy in a
turbulent fluid at length, R,
-
varies in proportion to
the 5/3rds power of R.
-
Experimental measurements
show Kolmogorov
-
was remarkably close to the
way turbulent flow works,
-
although a complete description of
turbulence remains
-
one of the unsolved problems in physics.
-
A turbulent flow is self-similar
if there is an energy cascade.
-
In ther words, big eddies
transfer their energy to smaller eddies,
-
which do likewise at other scales.
-
Examples of this include Jupiter's
great red spot,
-
cloud formations and
interstellar dust particles.
-
In 2004, using the Hubble space telescope,
-
scientists saw the eddies of a distant
cloud of dust and gas around a star,
-
and it reminded them of Van Gogh's
"Starry Night."
-
This motivated scientists from Mexico,
Spain and England
-
to study the luminence in Van Gogh's
paintings in detail.
-
They discovered that there is a distinct
pattern of turbulent fluid structures
-
close to Kolmogorov's equation
hidden in many of Van Gogh's paintings.
-
The researchers digitized the paintings,
-
and measured how brightness varies between
any two pixels.
-
From the curves measured for
pixel separations,
-
they concluded that paintings from
Van Gogh's period of psychotic aggetation
-
behave remarkably similar
to fluid turbulence.
-
His self portait with a pipe, from
a calmer period in Van Gogh's life,
-
show no sign of this correspondence.
-
And neither did other artists' work that
seemed equally trubulent at first glance,
-
like Munch's 'The Scream."
-
While it's too easy to say Van Gogh's
turbulent genius
-
enabled him to depict turbulence,
-
its also far too difficult to accurately
express the rousing beauty of the fact
-
that in a period of intense suffering,
-
Van Gogh was somehow able to
perceive and represent
-
one of the most supremely
difficult concepts
-
nature has ever brought before mankind,
-
and to unite his unique mind's eye
-
with the deepest mysteries
of movement, fluid and light.
Krystian Aparta
The English transcript was updated on 3/23/2015.