Self-study
Astrophysicist: Gamma ray bursts (GRBs)—explosions of powerful radiation from deep space—have traditionally been classified as either "short" or "long," terms that reflect the explosion's relative duration. ████████ ██ ███████ ███ ███ ████ ████████ ███ ████████ ███ █████ ███ ██ █████ █████ ███████ ██ ███ ███ ██████████ ██ █ █████ ████ ████████ ███ ███████████ ██████ ███████ ███ ██████ ████ ███ ████████ █████ ███████████
Summarize Argument
The astrophysicist concludes gamma ray bursts (GRBs) should no longer be called “short” or “long.” Why not? Because one recent GRB lasted a long time, but was more like a short GRB in every other way.
Notable Assumptions
The astrophysicist assumes there’s no use in labeling GRBs “short” or “long” if some GRBs are characteristic of the opposite type in every other way. In particular, this means assuming the “short” and “long” labels would only be useful if they always indicate properties of a GRB besides its actual duration.
6.
The conclusion of the astrophysicist's ████████ ██ ████ ████████ █████████ ██ █████ ███ ██ ███ █████████ ██ ████████
a
No other GRBs ████ ███████ ██████████ ████ ████ ████████
If anything, this weakens the argument. It suggests keeping the “short” and “long” labels will only lead to issues for a very small number of GRBs.
b
The classification of ████ ███ █████████ ██ ████ ██ ███ █████ ██ ████████ ██████
If anything, this weakens the argument. It suggests the “short” and “long” labels may still be useful for some GRBs—those for which duration is the distinctive property.
c
Properties other than ████████ ███ ████ █████████ ████ ████████ ██ ███ ██████ ██████████████ ██ ███ ███████ ████
This implies the “short” and “long” labels are really stand-ins for more important properties of unusual GRBs, which supports the astrophysicist’s contention that they should be abandoned for new labels.
d
GRBs cannot be ██████████ █████████ ██ ███ █████████ █████ ██ ██████ ██████ ████ ██████ █████
This is irrelevant. It implies cosmic origin, not duration, is a poor basis for classification.
e
Descriptive labels are ██████ ████████ ████ ██████████████ ██████ ████ ██ █████ ██ ███ █████ ████
This doesn’t mean the descriptive labels “short” and “long” are no longer useful. It’s possible nondescriptive labels would be even less useful than the descriptive ones.