Hello! We are Dr. Roman Berens, Prof. Alex Lupsasca, and Trevor Gravely (PhD Candidate) and we are physicists working at Vanderbilt University. We are excited to share Black Hole Vision: https://apps.apple.com/us/app/black-hole-vision/id6737292448.

Black Hole Vision simulates the gravitational lensing effects of a black hole and applies these effects to the video feeds from an iPhone's cameras. The application implements the lensing equations derived from general relativity (see https://arxiv.org/abs/1910.12881 if you are interested in the details) to create a physically accurate effect.

The app can either put a black hole in front of the main camera to show your environment as lensed by a black hole, or it can be used in "selfie" mode with the black hole in front of the front-facing camera to show you a lensed version of yourself.

First thing I wondered is what would happen if I pointed it another screen, with an image like this loaded. I realize that it's not realistic due to the z-axis, and field of view, but it's pretty fun.

https://esahubble.org/images/heic0609a/

Neat. I'll probably use it for five minutes, appreciate the math that went into it, and move on. But nevertheless, pretty neat.

I say that because there's an idea to play with for a v1.1 that would give it staying power for me:

Do you have enough processing power on an iPhone to combine this with Augmented Reality? That is to say: can you explore "pinning" a singularity in a fixed region of space so I can essentially walk around it using the phone?

Assuming that's possible, you could continue evolving this into a very modest revenue generating app (like 2 bucks per year, see where it goes?) by allowing for people to pin singularities, neutron stars, etc. around their world and selectively sharing those with others who pass by. I'd have fun seeing someone else's pinned singularity next to the Washington monument, for instance. Or generally being able to play with gravity effects on light via AR.

Very nice – if only I could try it! :'-) Any chance this could be ported to Android, at least for high-end devices with a decent GPU?

I recommend using a different preview screenshot on the App Store page. The first (most important) screenshot is without the effect at all. The use of the galaxy image doesn’t really reflect what it’s like to use the app.