The World

[asterroc]

I'm trying to understand something. Please answer the below questions to the best of your ability.

[Poll #1397877]

What I'm trying to understand is why my students are unable to distinguish between the planet Earth and the entire universe. For example, I said "1. How is the world (the planet Earth) going to end?
2. Which of the three scenarios for the end of the universe do YOU think is most likely?" And they answered #1 with "Big Crunch, Big Rip, or Heat Death," and for #2 picked their favorite. The correct response for #1 is "When the Sun runs out of Hydrogen in its core, it will expand as a red giant and engulf the planet Earth."

This time I explicitly wrote "(the planet Earth)" in the question to try and avoid the mix-up from the colloquial usage of the word "world". I think I need to just never ever use the word "world" again in astronomy.

Comments

[q10.livejournal.com]

a few examples of cases where ‘world’ means universe:

1. in metaphysics and semantics, one sometimes talks about ‘possible worlds’ when defining notions of metaphysical necessity or discussing the kinds of alternative, unreal states of affairs that we think about when we think about possibilities and uncertainties. in these areas, nothing is special about planets - its very clear that most writers in these areas (David Lewis is a striking example) are using ‘possible world’ to mean ‘possible way that the totality of everything that is’ could be, which, in ordinary talk, is pretty close to ‘possible universe’.

2. similarly, in epistemology, writers often draw distinctions between one's own mind and the external world (that can only be perceived through the senses) - here again planets aren't special - looking up at the sky on a clear night is still taking in sensory impressions of the world.

3. in theological contexts, people frequently use ‘the world’ to mean ‘the sum of all creation’ - see e.g. Cat Faber's deist hymn The Word of God - when she writes ‘Humans wrote the Bible, God wrote the world.’, it's pretty clear she means the whole of natural reality, including at least the sky that was mentioned in a pervious verse.

4. i'm pretty sure the many worlds interpretation of QM isn't about planets being special.

[zandperl.livejournal.com]

*nods* There's definitely a colloquial usage of "world" to mean "everything" or "universe", and I expect either your #2 or #3 is where that colloquial usage comes from.