  Entanglement swapping generates remote quantum correlations between particles
that have not interacted and is the cornerstone of long-distance quantum
communication, quantum networks, and fundamental tests of quantum science. In
the context of spatial modes of light, high-dimensional entanglement provides
an avenue to increase the bandwidth of quantum communications and provides more
stringent limits for tests of quantum foundations. Here we simultaneously swap
the entanglement of multiple orbital angular momentum states of light. The
system is based on a degenerate filter that cannot distinguish between
different anti-symmetric states, and thus entanglement swapping occurs for
several thousand pairs of spatial light modes simultaneously.
