No. most of graphics card and video decoding mechanism doesn't like to play square video such as 2048x2048, 3840x3840. You can try 1920x1080 or 3840x 2160 instead of.
If you are going to publish app, following guide-line would be helpful.
As Samsung describe the doc, following format is suggested for GearVR
- Suggested Monoscopic Configuration: 4096x2048 video at 30 FPS, encoded with H.264.
- Suggested Stereoscopic Configuration: 3840×2160 video at 30 FPS, encoded with H.265/VP9 10-20mbps bitrate.