Q20

[Yu440]

Patrick can you help me please!

I chose D because I thought line 36-38 was the Most Valuable Point: "Carroll and Chen's innovation is to argue that the most common initial condition is actually likely to resemble cold, empty space".

But is D wrong because Carroll and Chen agrees that a small, hot, and dense configuration IS indeed an initial condition for a universe, it's just that they think the MULTIVERSE as a whole is mostly cold and empty?

B) wrong because it focuses on a supporting point
C) I was tempted by this one as well. But I guess they don't challenge that view, they just think that the Big Bang happened many times?
E) only a minor point

So what really is the purpose of this passage? That the Big Bang was not an unique event?

This is a tricky passage! (Well I thought I understood it well until I realized I got four questions wrong!) Any tips on how to tackle such passages during the test? Thanks!!

[ohthatpatrick]

I see why you're drawn to line 36, but "their innovation" is what allowed them to reach "their conclusion", and "their conclusion" is more the main point.

THEIR CONCLUSION:
big bangs are not unique ... they happen periodically over big time scales (said first in lines 6-9, and then echoed again at the end in lines 51-53)

THEIR EVIDENCE:
a high entropy multiverse would still have lots of tiny areas of empty space, and these other physicists have shown that fluctuations in these tiny areas can generate their own big bangs.

ANSWERS
(A) Maybe. It's an accurate description of where they think our big bang came from

(B) Way too narrow. This is about entropy, but the main point should be about where the big bang came from / why that means it's probably not unique

(C) They are definitely not challenging inflation. They would only be challenging the idea that the Big Bang is unique.

(D) This is a supposition that helped them reach their insight that maybe the initial condition was just empty space, which helped them reach their eventual conclusion that the big bang is not unique.

(E) They probably would posit that, but it's not super germane to the notion of where the big bang came from and why that means it's probably not unique

I guess I'd come home to (A). It is still embodying "their innovation", because the notion of "an energy fluctuation in a high entropy multiverse" is the same as their innovation that "we didn't come from a low entropy singularity ... we came from a fluctuation of energy in a tiny patch of empty space within a high entropy multiverse".

Hope this helps.