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Comment by Aerroon | Hacker News Reader

>So under this hypothesis, a black hole never reaches a true singularity, but as close to a singularity as physically possible, and then it almost instantaneously bounces back like a taut rubber band that's stretched back as far as it'll go.

Kind of like a graph of 1/x, where everything behaves predictably, but there's that one point that doesn't fit?

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I'm absolutely terrible and uneducated when it comes to math, so I'm not sure exactly what you mean. But if you mean 1/x where x = infinity, then yes, the classical idea of a singularity (such as what's been theorized to exist within a black hole, curving to an infinitely small point) is basically like 1/infinity or dividing by zero.

Rovelli hypothesizes this never actually happens and is not physically possible, and rather, when the most physically extreme possible level of curvature does occur, it "snaps back". If true, this ensures black holes do actually behave predictably, and physics doesn't actually break down; it just gets as extreme as it can possibly get.

So under this hypothesis, x gets really high, but the universe prevents it from ever reaching infinity. This would also potentially resolve some paradoxes related to black holes.

I'm not terribly educated either, but if you don't mind a minor possible correction, I suppose GP would have meant x = 0, which is the only point where the function would be typically undefined, and the closer x gets to 0, the more f(x) approaches infinity. Conversely, the more x approaches infinity, the more f(x) approaches 0. Also, because of the way these things are usually defined, it doesn't make sense to say x = infinity, it only makes sense to say x approaches infinity (but it might make sense in nonstandard calculus, where infinitesimals are defined - here my ignorance already shows).

I really appreciate your comments! If you're interested in hypothesizing about physics, I think it would do you a lot of good to learn at least a bit of math to go with it.

> "I really appreciate your comments! If you're interested in hypothesizing about physics, I think it would do you a lot of good to learn at least a bit of math to go with it."

Not disagreeing, I just wanted to suggest that the ideas come first, right? The math simply frames the ideas in a way that we can quantify and discuss, while also providing a "line in the sand" that other ideas must be compatibile with in order to be accepted among other the ideas that have already crossed that line. Those are very important things, but I would suggest that they are merely supporting an original idea that does not require math to intuit.

Although there is projective space where it does make sense to say x = infinity (and also that f(0) is defined). In projective space all of the conic sections (lines, hyperbolas, ellipses, parabolas) are connected loops.

Thanks, I knew it had to be either zero or infinity. A singularity would indeed be like dividing by zero, which is why, if they exist, physicists would have a lot of trouble describing them mathematically.

I almost never really think or talk about physics in general. This thread just caught my eye.

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