Which of the following ideas was not proposed by Democritus in his theory of the universe

Explanation:

"Atoms" in Greek means "indivisible." Democritus called his discovery this because he believed that the atom was unbreakable into smaller parts. To initially find the atom, Democritus conducted a simple experiment that can still be done today. What he did was take a simple seashell and break it in half.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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