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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?

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.

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.

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/

Did anybody else first think —before seeing the app images— that it was somehow using the camera of the iPhone to simulate the physics of the black hole?

Just tried to check it out. First boot it crashed, killed app and tried again and now it won’t open. I’ll try and reinstall and do over. iPhone 16 Pro, iOS 18.1

Quick edit- I did exactly that and now it works fine. First boot up before seemed like it got stuck when asking for permission to use the camera.

>physically accurate >event horizon doesn't appear in my room :(

This is awesome. I see that this is GPL and open on GitHub. Thank you for sharing. If you are open to feature requests that I am too lazy and stupid to accomplish on my own, I would appreciate the option to drop the multi camera view and the option to capture a photo. Also plus one to the idea of being able to pin the black hold to a specific orientation so you can see what it looks like to pan around an object adjacent to the black hole.

Instant download for me. I’m a sucker for anything black hole related.

Pendatic but can I ask why does this app require 17.5 or later? For reference, the latest iOs version is 18. What specific API is being used to require that version?

I wonder if this would be better as a webpage and not an app. It’s something I want to share far and wide for everyone to play with for five minutes. But as an app, most people I send it to won’t go install it.

I’m no astrophysicist but it all looks doable with the camera API, canvas API, and WebGL or WebGPU shaders. That actually sounds like a lot of fun.

Not related to the app, but could someone explain how something with huge though finite mass can create a singularity which is a point of infinite density? Can there also be black holes which are just dark stars with intense gravity having a hard surface?

> Data Not Collected

> The developer does not collect any data from this app.

Well, duuh, nothing can escape the black hole, not even information!

That seems cool. It would be interested to see a simulation for Kerr-Newman BH. Although I have no idea what would be the best way to see the effects without some sort of perturbation. Not that this is astrophysical BH of course. Just a thought experiment.

Does anyone else find it jarring to unexpectedly be shown the selfie camera view? Showing both camera feed thumbnails constantly while using this app is a little odd.

Still, kinda fun, reminds me of playing around with different blur / liquidify filters in photoshop back in the day.

Would a person notice red-shifts from the black hole as well?

As above so below. I love how it looks so similar to a colonoscopy.

As always, wonder what a particular "free" thing is selling and to whom. In this case it's something called BHEX, to NASA.

Oh man this so reminds me of the old iPhone apps which were so epic and so cool

Does it use iPhone-specific features or could it work on, e.g., a desktop

Is in the middle of black hole zero gravity? Then, is there another event horizon somewhere inside black hole?

So cool! Vision Pro version?

What happens with the rotating one and a realistic POV?

No plans for an Android version?

Another nice feature would be if it could simulate an accretion disk.

Dad

This is not a simulation of a black hole, but rather an image filter that emulates one particular effect.

A bit off topic, but does anyone else get weird nightmares of black holes?