Tarot cards: Judgement
Part of my ongoing tarot card art project.
Judgement, modernized. Because this, if anything, needs to be.
One of the assigned meanings of the card is "causality", so I initially played around with the idea of a character holding an abstract representation of a light cone, or a group of characters gathered around a light cone.
In Einstein's special relativity, due to the finite speed of light, only events within the past light cone of a given event can causally affect that event, and that event can causally affect only events in its future light cone. Hence in the visual language of modern physics, a light cone is a convenient visual symbol for causality.
But it turns out that Illustrious can't draw light cones, or indeed any kind of double cones that fit together in a hourglass shape. Prompting for an hourglass didn't help, either. So after some unsuccessful rerolling, I ended up scrapping that idea. It might be possible with techniques similar to what I used in the Justice card, but here I decided to try something else.
Looking for options, in mythology, The Judgement is something that occurs at the end of time. So could we depict, in a modernized way, the end of time instead?
Via general relativity: yes.
The thing with black holes is that, from the viewpoint of an external observer, the event horizon surface exists at the end of time. As they observe an object falling into the black hole, the motion of that object seems to increasingly slow down, and any light emitted by the object redshifts ever further, until the object seems to freeze in place at the event horizon, at infinite redshift.
For an infalling observer, the same scenario looks different (visualizations [1] [2]). Their local time continues as usual as they cross the event horizon. However, once inside the black hole, eventually spacetime becomes so distorted that motion forward through time itself becomes spatial motion toward the central singularity. Which the infalling observer hits a short, finite amount of local time later. At that point, the observer's worldline... just ends. Read into that what you will.
For those with a university-level math background, I heartily recommend Wolfgang Rindler's Relativity: Special, General, and Cosmological. For those following the genre, yes, that's the Rindler of Rindler coordinates fame. I found the book extremely clearly written, explaining general relativity almost as if it's not rocket science. Some basic familiarity with tensors is recommended. But in return, just reading through, you'll come away with an understanding of the basics of general relativity, for example, the classic Schwarzschild black hole. This is no mean feat, as GR is often (for good reason) considered a difficult theory.
But it's been a decade since I read the book, and I haven't used GR since, so don't ask me any detailed questions, lol.
Getting back to the artistic side of things, Illustrious doesn't quite know how to render a black hole, but maybe this image, allowing for some artistic liberties (not the least being that she's not wearing a helmet), is close enough to evoke the concept.
(Black holes don't actually appear entirely black. Yes, they emit Hawking radiation, which, as countless aeons pass, will eventually cause them to evaporate. But more importantly for their visual appearance in the near term, the accretion disk can be pretty bright across the electromagnetic spectrum. The high gravitational field makes visualization nontrivial, because gravity affects light, too. The first actual photo of a black hole was taken in 2019. The one at the center of our galaxy was also photographed later, in 2022.)
Notes
WAI-NSFW-illustrious-SDXL v13.0, with inpainting.
Selectively combining renders in an image editor (such as GIMP) is a powerful technique.