Walking through the Arsenale portion of Okwui Enwezor’s central show for the Venice Biennale, “All the World’s Futures,” you reach an empty section that is cordoned off, with a long row of desks holding various tools and unplaceable objects off to one side. Yesterday, when the show opened, a man was sitting there and tinkering with something. It was the Argentinian artist Ernesto Ballesteros. He hopped up, holding a very light-looking toy airplane, which he showed to a few viewers, and then gently let it drop out of his hand. It began flying at a glacial place, almost hovering in the air, like it was part of its own universe. And then, after 10 very long seconds, he snapped it back up and the normal laws of physics seemed to govern reality once again. The work is called Indoor Flights (2015). Below, a video clip of the flight.