Scientist

Henri Poincaré

1854-1912 · mathematics, theoretical physics, astronomy, philosophy of science
French mathematician, theoretical physicist, and philosopher of science. He laid the foundations of special relativity, predicted the existence of gravitational waves, and made fundamental contributions to celestial mechanics, topology, and chaos theory. He is considered one of the greatest mathematicians of all time and the last universalist capable of covering all science.

Biography

Born in Nancy, France. Studied at the École Polytechnique and the École des Mines in Paris. He was a professor at the Sorbonne and a member of the French Academy of Sciences. In addition to physics and mathematics, he engaged in the philosophy of science and wrote several well-known books on methodology. His cousin was the President of France, Raymond Poincaré. He received many awards, including the Lorentz Medal.

Key discoveries

💡 Poincaré had a phenomenal memory and the ability to visualize multidimensional spaces; he solved complex problems mentally without using drafts. Despite severe nearsightedness, he never wore glasses, preferring his inner world.
"He considered science a cemetery of hypotheses where many beautiful ideas rest."
Concepts
differential formgravitational wavesspeed of light
Laws
principle of constancy of the speed of lightLorentz transformationsprinciple of least actionPoincaré recurrence theorem
Scientists
Fritz ZwickyRainer WeissStephen HawkingJames Clerk MaxwellJoseph WeberHendrik LorentzChristian DopplerArthur Compton

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An Air Pendulum Over the Pacific
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The Coast as Rain Conductor
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A Map That Could Have Predicted El Niño
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El Niño: Predicting Strength and Onset a Year in Advance
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Stellar2017-06-282 minarXiv:1706.09105
The Sun's Two Pendulums: How Coupled Oscillations Create a 90-Year Rhythm
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The Pendulum That Forgets How to Swing
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Relay of Chaos: How Warm Pacific Waters Make Weather Unpredictable
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El Niño and the Indian Monsoon: A Connection Under Pressure
The dance between two partners, the ocean and the sky, has been going on for thousands of years. El Niño warms the Pacific, and usually at the same time seasonal rains over India weaken. But in recent decades, the rhythm seems off: rains don't always respond to the warm current.
A Council of a Hundred Short Experts Predicts El Niño's Whims
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The Breath of Monsoons: How Random Gusts Settle into a Predictable Rhythm
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The Cold Dance Around Antarctica: A Wave That Never Stands Still
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The Forest That Sometimes Falls Silent, Sometimes Sings: The Dynamics of the Drake Equation
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Ocean Memory Quenches El Niño Chaos
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The Monsoon That Turned Out More Predictable Than We Thought
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