Warning: This article contains spoilers for The Flash season 5 episode 9
The Arrowverse's "Elseworlds" crossover may have already answered a question that superhero fans have debated for decades: who is faster, the Flash or Superman? The two have raced several times - in comics, cartoons, and even movies. The outcome has usually been fairly inconclusive, although it's generally been suggested that the Flash is faster.
There's never been a race between the Flash and Superman in the Arrowverse, of course; the two heroes don't even exist in the same universe, and as a result they haven't crossed paths until this week's "Elseworlds" event. Moreover, this first episode saw them team up rather than fight against one another, so they certainly weren't competing in a race. Nevertheless, it did still subtly hint which one of the characters is the faster.
"Elseworlds Part I" sees the assembled heroes go up against the threat of the A.M.A.Z.O., an android with the ability to duplicate the powers of any metahuman it encounters. Although the superheroes initially manage to keep it off-balance, they unwittingly give A.M.A.Z.O. a chance to scan them and copy their powers. As a result, it winds up possessing all the powers of Flash, Superman, the Elongated Man, and Killer Frost.
A.M.A.Z.O. is a machine intelligence, and as such it's reasonable to assume that the android will select the optimum power to deal with any given threat. There are a number of scenes where A.M.A.Z.O. uses Flash's super-speed, including a couple where it chases him through Central City. Significantly, it always chooses to use Flash-powers on those occasions, as demonstrated by the distinctive lightning effect. There's only one brief scene where A.M.A.Z.O. uses Kryptonian flight-powers to pursue Flash, and even then the android quickly takes to the ground to continue on-foot. This clearly indicates that A.M.A.Z.O. considers Flash's super-speed to be more effective than Superman's speed or even his power of flight. That's all the more remarkable considering that, while running on foot, A.M.A.Z.O. will frequently need to dodge around obstacles.
This is only a subtle detail, but it may well be more significant than any race between the two superheroes. After all, in the comics the races have usually been orchestrated by enemies such as Mr. Mxyzptlk, with Superman and Flash coerced into taking part. In this case, though, an android brain designed to switch between super-powers has considered the Flash's speed to be its optimum choice to use. Machine intelligence is logical and impartial; it seems that, in the Arrowverse, Flash is indeed the fastest man alive.