public function toArray(): array
    {
        $array = parent::toArray();
        $array["creator"] = $this->creator_id;
        $array["registered_edges"] = [
            "in" => $this->incoming_edges,
            "out" => $this->outgoing_edges,
        ];
        if($this instanceof Actor) {
            $array["notifications"] = $this->notifications()->toArray();
        }
        return $array;
    }