Astronomy
Astronomy (from Greek: ἀστρονομία) is a natural science that studies celestial objects and phenomena. It applies mathematics, physics, and chemistry, in an effort to explain the origin of those objects and phenomena and their evolution. Objects of interest include planets, moons, stars, galaxies, and comets; the phenomena include supernova explosions, gamma ray bursts, and cosmic microwave background radiation. More generally, all phenomena that originate outside Earth's atmosphere are within the purview of astronomy. A related but distinct subject, physical cosmology, is concerned with the study of the Universe as a whole.
Physics
Physics (from Ancient Greek: φυσική (ἐπιστήμη), translit. physikḗ (epistḗmē), lit. 'knowledge of nature', from φύσις phýsis "nature") is the natural science that studies matter and its motion and behavior through space and time and that studies the related entities of energy and force. Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves.
Physics
Theoretical physicists live in a classical world, looking out into a quantum-mechanical world. The latter we describe only subjectively, in terms of procedures and results in our classical domain.
John Stewart Bell "Introduction to the hidden-variable question" (1971), included in Speakable and Unspeakable in Quantum Mechanics (1987), p. 29
Teachers
Grave is the Master's look; his forehead wears
Thick rows of wrinkles, prints of worrying cares:
Uneasy lies the heads of all that rule,
His worst of all whose kingdom is a school.
Supreme he sits; before the awful frown
That binds his brows the boldest eye goes down;
Not more submissive Israel heard and saw
At Sinai's foot the Giver of the Law.
Oliver Wendell Holmes, Sr., The School Boy.
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