Don’t Trust Headlines

The typical way to multiply large numbers: long division.

Even though something like “Don’t Trust Headlines” sounds like a political statement (“Fake News!” and all that), it is actually something that I often encounter in the sciences.

Here is a recent example I encountered. It actually has to do with math, rather than science, but mathematics is closely related enough to science, so I think it counts. The headline is:

This Guy Found a Faster Way to Multiply: Because the method you learned in middle school is ridiculously slow[1]

Granted, this is a headline from GetPocket.com, not exactly a science savvy site, and by calling a mathematician “this guy,” we can certainly expect that the article was written for an audience that is not science savvy, either. Nevertheless, when I saw this headline, I wondered, “What is this about? Are mathematicians coming up with a ‘better and improved’ way to do multiplication? Are people expecting us to change how we teach mathematics?” After all, if “the method you learned in middle school is ridiculously slow,” could things be better by learning this faster multiplication method?

Then I read the article. First of all, “this guy,” who is a mathematician named David Harvey, didn’t come up with a new method of multiplying. Instead, he helped prove a conjecture that was first given in 1971. So “this guy” didn’t find anything, so much as he successfully demonstrated what was previously a conjecture.

How will this faster method of multiplying change our lives? It won’t. See, this “new way” of multiplying involves logarithms, which is not exactly a subject taught in middle school. So don’t expect this faster method of multiplication popping up in middle school curriculum any time soon. The main application will actually be in computers. Specifically, when a computer is asked to multiply numbers with billions of digits, the method of long division takes too long. This faster method cuts down on the computer’s computational time significantly.

So there you have it. Computers can now multiply billion digit numbers faster than they did previously. Which is interesting, but “Computer Calculations Will Now be Faster” does not have the same zip to it as “Because the method you learned in middle school is ridiculously slow.” It just goes to show that the purpose of a headline is to grab its reader’s attention, and if it takes exaggerating the significance of a discovery, writers will do that with surprising regularity.


[1]Grossman, David (2021) “This Guy Found a Faster Way to Multiply” getpocket.com, retrieved from https://getpocket.com/explore/item/this-guy-just-found-a-faster-way-to-multiply?utm_source=pocket-newtab on November 30, 2021