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Explain xkcd: It's 'cause you're dumb.
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Data Error
Cyanobacteria wiped out nearly all life on Earth once before, and they can do it again!
Title text: Cyanobacteria wiped out nearly all life on Earth once before, and they can do it again!


Megan is frustrated that a data error invalidates her research, which she was just ready to publish. Black Hat tells her not to panic and states there are two options.

Option one is to redo her analysis and share the correct results, even if negative. Negative results can be important, and although it would be disappointing, she would be trying to extract some value from the research.

Option two fits the classhole expectation from Black Hat, as he suggests that she should destroy the evidence, use her research materials to build a superweapon, and use it to conquer the world and rule it with an iron fist.

At first Megan seems excited about this idea, but then she reveals that this second suggestion is not really an option, since her research is about the productivity of algae -- a topic not likely to lead to conquering the world. Humorously she states that at least she can make people tremble before her and her anomalously productive algae, only to realize that it was the data error that made her algae look productive. They are in fact merely normal algae, and she corrects herself to Tremble before my normal algae! She is of course making a joke on Black Hat.

Destroying the evidence, hiding the error and publishing the wrong results as if they were right is what a dishonest scientist would do in such a situation. This behavior is what would be expected by a malevolent character such as Black Hat... But the unexpected turn is that Black Hat passes over scientific misconduct to go directly to pure supervillainhood. He obviously has some other ideas about what a researcher uses her time on, as he did not expect Megan to be frustrated about algae.

The title text refers to the Great Oxidation Event, when prokaryotic photosynthetic organisms built up oxygen in Earth's atmosphere for the first time and most organisms, which weren't adapted to oxygen, went extinct. It's extremely unlikely that algae could again be dangerous to all life on Earth, though Black Hat may wish they could be. (Note that cyanobacteria, which are colloquially referred to as "blue-green algae", are not considered to be true algae by many scientists, who restrict the term to eukaryotes.) On the other hand, algae and cyanobacteria can still be locally harmful.

Megan's data error could have been any number of things. Her data pipeline might have had a unit conversion error, or perhaps she mistyped the baseline productivity value that she was comparing her algae to, or perhaps her calculations used assumed or estimated values related to phenomena that were poorly understood at the time but have since been resolved in an unfavorable direction.

Whatever Megan's data error was, it seems harmless enough, but a similar data error spurred the development of nuclear weapons. In 1940, Otto Frisch and Rudolf Peierls wrote a memo "On the construction of a 'superbomb' based on a nuclear chain reaction in uranium". In this memo, Frisch and Peierls estimated that only 570 grams of uranium-235 would be required to construct a "superbomb" (what we now call a nuclear weapon), compared to many tons of natural uranium-238. This inspired the British and American governments to begin developing infrastructure for uranium enrichment through the Tube Alloys and Manhattan Project programs. Later experiments in these programs revealed that the values Frisch and Peierls had used for uranium's density and nuclear cross-section were overestimates (the true critical mass is actually around fifty kilograms), but by that time, the programs were far enough along that they could simply press on with enriching more material to eventually produce working weapons.


[Megan is talking to Black Hat.]
Megan: I can't believe this data error invalidates a year and a half of my research.
Megan: I was about to publish.
[In a frame-less panel Black Hat replies while holding two fingers up one on either hand.]
Black Hat: Don't panic. You have two options.
Megan: Yeah?
[Closeup shot of Black Hat holding one hand out with the palm up.]
Black Hat: 1) Redo your analysis and share whatever results you can, whether positive or negative. It's disappointing, but these things happen.
[Zoom out on Black Hat and Megan. Black Hat holds his closed fist up in front of him. Megan throws both arms up in the air.]
Black Hat: 2) Destroy the evidence. Use your materials and research methods to build a superweapon. Conquer Earth and rule with an iron fist.
Megan: Tremble before my anomalously productive algae!
Megan: Except the anomaly was an artifact.
Megan: Tremble before my normal algae!

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