I found some papers which propose alternative methods (source: https://MirrorThink.ai):

1. Point-NeRF: Point-based Neural Radiance Fields - 2022: This paper presents Point-NeRF, a localized neural representation that combines volumetric radiance fields with point clouds to model complex local scene geometry and appearance. It achieves better rendering quality than NeRF and is more efficient in reconstructing complex and large-scale scenes.

2. TensoRF: Tensorial Radiance Fields - 2022: TensoRF proposes a tensorial radiance field representation that can achieve fast reconstruction and high rendering quality. It is significantly faster than NeRF and many previous methods.

3. GazeNeRF: 3D-Aware Gaze Redirection with Neural Radiance Fields - 2022: GazeNeRF incorporates 3D awareness with gaze redirection by applying a rotation matrix to the disentangled eyeball feature maps. It represents a static scene with multi-layer perceptrons and maps the 3D positions and viewing directions to a density and radiance for generating novel views with volume rendering.

[1] https://arxiv.org/abs/2212.04823

[2] https://arxiv.org/abs/2203.09517

[3] https://arxiv.org/abs/2201.08845