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One of the most remarkable aspects[br]of the human brain

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is its ability to recognize patterns[br]and describe them.

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Among the hardest patterns[br]we've tried to undestand

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is the concept of[br]turbulent flow in fluid dynamics.

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The German physicist[br]Verner Heisenberg said,

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"When I meet God, I'm going to ask him[br]two questions:

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why relativity and why turbulence?

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I really believe he will have [br]an answer for the first."

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As difficult as turbulence is to[br]understand mathematically,

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we can use art to depict the way it looks.

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In June 1889, Vincent Van Gogh painted[br]the view just before sunrise

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from the window of his room at the[br]Saint Paul de Mausole Asylumn

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in Saint-Rémy-de-Provence,

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where he'd admitted himself after[br]mutilating his own ear

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in a psychotic episode.

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In the Starry Night, [br]his circular brush strokes

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creates a night sky filled with[br]swirling clouds and eddies of stars.

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Van Gogh and other impressionists[br]represented light in a different way

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than their predecessors,[br]seeming to capture its motion,

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for instance, across sun dappled waters,

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or here in star light that [br]twinkles and melts

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through milky waves of blue night sky.

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The effect is caused my luminance,

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the intensity of the light in the colors [br]on the canvas.

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The more primitive part of our[br]visual cortex,

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which sees light contrast and motion,[br]but not color,

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will blend two differently [br]colored areas together

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if they have the same luminance.

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But our brains primate[br]subdivision

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will see the contrasting colors[br]without blending.

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With these two interpretations[br]happening at once,

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the light in many impressionist works[br]seems to pulse, flicker and radiate oddly.

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That's how this and other impressionist[br]works use quickly executted

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prominent brush strokes to capture[br]something strikingly real

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about how light moves.

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60 years later, Russian mathematician[br]Andrey Kolmogorov,

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furthered our mathematical [br]understanding of turbulence

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when he proposed that energy in a[br]turbulent fluid at length, R,

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varies in proportion to [br]the 5/3rds power of R.

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Experimental measurements[br]show Kolmogorov

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was remarkably close to the [br]way turbulent flow works,

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although a complete description of[br]turbulence remains

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one of the unsolved problems in physics.

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A turbulent flow is self-similar[br]if there is an energy cascade.

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In ther words, big eddies[br]transfer their energy to smaller eddies,

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which do likewise at other scales.

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Examples of this include Jupiter's[br]great red spot,

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cloud formations and[br]interstellar dust particles.

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In 2004, using the Hubble space telescope,[br]

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scientists saw the eddies of a distant[br]cloud of dust and gas around a star,

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and it reminded them of Van Gogh's [br]"Starry Night."

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This motivated scientists from Mexico, [br]Spain and England

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to study the luminence in Van Gogh's[br]paintings in detail.

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They discovered that there is a distinct[br]pattern of turbulent fluid structures

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close to Kolmogorov's equation[br]hidden in many of Van Gogh's paintings.

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The researchers digitized the paintings,

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and measured how brightness varies between[br]any two pixels.

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From the curves measured for[br]pixel separations,

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they concluded that paintings from[br]Van Gogh's period of psychotic aggetation

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behave remarkably similar [br]to fluid turbulence.

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His self portait with a pipe, from[br]a calmer period in Van Gogh's life,

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show no sign of this correspondence.

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And neither did other artists' work that[br]seemed equally trubulent at first glance,

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like Munch's 'The Scream."

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While it's too easy to say Van Gogh's[br]turbulent genius

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enabled him to depict turbulence,

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its also far too difficult to accurately[br]express the rousing beauty of the fact

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that in a period of intense suffering,

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Van Gogh was somehow able to[br]perceive and represent

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one of the most supremely [br]difficult concepts

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nature has ever brought before mankind,

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and to unite his unique mind's eye

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with the deepest mysteries[br]of movement, fluid and light.