- What is Entropy? (johncarlosbaez.wordpress.com)
It’s easy to wax poetic about entropy, but what is it? I claim it’s the amount of information we don’t know about a situation, which in principle we could learn. But how can we make this idea precise and quantitative? To focus the discussion I decided to tackle a specific puzzle: why does hydrogen gas at room temperature and pressure have an entropy corresponding to about 23 unknown bits of information per molecule?
- What is Entropy? (jasonfantl.com)
People say many things about entropy: entropy increases with time, entropy is disorder, entropy increases with energy, entropy determines the arrow of time, etc.. But I have no idea what entropy is, and from what I find, neither do most other people. This is the introduction I wish I had when first told about entropy, so hopefully you find it helpful. My goal is that by the end of this long post we will have a rigorous and intuitive understanding of those statements, and in particular, why the universe looks different when moving forward through time versus when traveling backward through time.
- Book of Isaiah (Wikipedia)
The Book of Isaiah (Hebrew: ספר ישעיהו, [ˈsɛ.fɛr jə.ʃaʕ.ˈjaː.hu]) is the first of the Latter Prophets in the Hebrew Bible and the first of the Major Prophets in the Christian Old Testament. It is identified by a superscription as the words of the 8th-century BCE prophet Isaiah ben Amoz, but there is extensive evidence that much of it was composed during the Babylonian captivity and later. Johann Christoph Döderlein suggested in 1775 that the book contained the works of two prophets separated by more than a century, and Bernhard Duhm originated the view, held as a consensus through most of the 20th century, that the book comprises three separate collections of oracles: Proto-Isaiah (chapters 1–39), containing the words of the 8th-century BCE prophet Isaiah; Deutero-Isaiah (chapters 40–55), the work of an anonymous 6th-century BCE author writing during the Exile; and Trito-Isaiah (chapters 56–66), composed after the return from Exile. Isaiah 1–33 promises judgment and restoration for Judah, Jerusalem and the nations, and chapters 34–66 presume that judgment has been pronounced and restoration follows soon. While virtually no scholars today attribute the entire book, or even most of it, to one person, the book’s essential unity has become a focus in more recent research.
- Entropy (Wikipedia)
Entropy is a scientific concept, as well as a measurable physical property, that is most commonly associated with a state of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the microscopic description of nature in statistical physics, and to the principles of information theory. It has found far-ranging applications in chemistry and physics, in biological systems and their relation to life, in cosmology, economics, sociology, weather science, climate change, and information systems including the transmission of information in telecommunication.