#20 - Global Reference, Must Be True

[a.hopp]

A little more detail on why A is a better answer than E would be helpful. I had initially chosen a and changed it to D (I should know to stick with my first answer by now).

I ended up choosing E because I thought the main idea brought up throughout the passage was that our universe was one of many - not unique, and its creation was a singular event, not the beginning of the "Multiverse," which our universe is a part of.

I understand Carroll and Chen ended up revising their hypothesis to be that our universe was the result of an energy fluctuation, but I did not realize this was the main idea of the entire passage.

[Rachael Wilkenfeld]

Answer choice (E) doesn't pass the accuracy test, a.hopp.

For main point answer choices, the correct answer choice must both be accurate according to the passage, as well as correctly describe the author's main point. I typically eliminate answer choices once they don't pass the FACT test without further thought about if they are close to the main point. In fact, the test makers will frequently play this game---they will have an attractively worded answer choice available, but make it not fully supported by the information in the passage.

Answer choice (E) is one such answer choice. Carroll and Chen did not posit that there's a multiverse. They built on their work on the idea of a multiverse. If you read paragraph 2 carefully here, you'll see that the author never names the "some scientists" who were the ones to initially posit that our universe is a part of the multiverse. Carroll and Chen pushed the idea of a multiverse a bit further and described the specifics that would lead to our universe. That's best represented by answer choice (A).

Hope that helps!

[andy12]

Reading the above answers has been helpful in why to choose A and avoid E. However, I did first choose E, since I took this part of the passage to consider A a loser:

"Such a low entropy universe is an extremely unlikely configuration, not what scientists would expect from a randomly occurring initial condition. Carroll and Chen’s innovation is to argue that the most common initial condition is actually likely to resemble cold, empty space—not an obviously favorable starting point for the onset of inflation."

Does this not state that low entropy = cold, empty space, not favorable...? I was turned off by choosing an answer that had "high entropy", when I considered C+C's theory to argue that it starts in low entropy? Or should I assume that by now everything that ever began at some time is now high entropy?

Thank you!

[andy12]

I may be answering my own question, but I would still love to hear an expert weigh in. To counter my statement above, is the part that makes A correct the final sentence of paragraph 5? "Carroll and Chen take our universe, and others, to be such fluctuations in a high entropy multiverse."

[Rachael Wilkenfeld]

Hi Andy,

I think the issue you are running into is keeping track of all the different viewpoints and perspectives in this one. Let me break down the relevant sections for you.

First, the puzzling fact here is that the universe as we know it came from a dense, hot expanding bubble (the Big Bang) but that isn't a likely position for the universe to start in. So how is it that ours did? What could solve the mystery?

Here's where C and C come in to explain. They contend that the most likely state for a universe to start is cold and scattered, BUT (here's the key) there are bubbles within the cold state that are likely hot and dense. Our universe started from one of these bubbles in a generally cold universe. C and C acknowledge that the cold empty state is likely the main starting point, but they go further and say that on the scale of an entire universe, SOME areas are likely to be hot and dense. Even if there are only a few of those areas, just one would be enough to start a bubble universe that looks like ours.

The quote you pulled is exactly the right place to look. Good work!