This article unfortunately imho does a poor job in putting the mathematical modeling and Hintz' effort into greater focus and context. Possibly to make it more exciting for the casual science interested reader.<p>"Some <i>carefully constructed mathematical objects</i> (similar to observed black holes) erase your past (makes it possible to cross the <i>Cauchy horizon</i>)" in GR would be more precise.<p>Here [0] is a good article about the kind of mathematical manipulation involved (not directly related).
This [1] quora answer goes right to the obvious issues.<p>[0]<a href="https://www.quantamagazine.org/to-test-einsteins-equations-poke-a-black-hole-20180308/" rel="nofollow">https://www.quantamagazine.org/to-test-einsteins-equations-p...</a><p>[1]<a href="https://www.quora.com/Is-the-violation-of-strong-cosmic-censorship-derived-by-Peter-Hintz-relevant-to-the-interiors-of-astrophysically-realistic-black-holes/answer/Alessandro-Takeshi" rel="nofollow">https://www.quora.com/Is-the-violation-of-strong-cosmic-cens...</a>
> In the real world, your past uniquely determines your future. If a physicist knows how the universe starts out, she can calculate its future for all time and all space.<p>[Layman here] Is this ignoring quantum mechanics? Or is the claim that you can reconstruct the original wavefunction a collapse? I thought randomness was pretty intrinsic to quantum mechanics.
<a href="https://physics.stackexchange.com/questions/403574/what-situations-in-classical-physics-are-non-deterministic" rel="nofollow">https://physics.stackexchange.com/questions/403574/what-situ...</a><p>Non deterministic dynamics occurs in Newtonian physics as well. These things are worrying philosophically, but we can take some comfort in that the initial conditions for which these occur are "measure zero" i.e. if you were defining a probability measure over initial conditions, then the non-deterministic initial conditions would have measure zero. It doesn't sound like we have that option here though.<p>But in my view, this result is good news. We knew GR was unphysical anyhow. Now we've increased our understanding of how unphysical it is, potentially ruling out more replacement theories.
> "<i>If a physicist knows how the universe starts out, she can calculate its future for all time and all space.</i>"<p>This seemingly innocent statement could render a prolific discussion. Branching so many ways...<p>Which one would you like to pick?<p>Loss of simultaneity, from relativity theory [1]<p>Consistent histories and probabilistic future prediction by quantum mechanics [2]<p>Free will -- upfront this can sub-branch into biology, psychology, philosophy, artificial intelligence... [3] [4] [5]<p>"The Best Way To Predict The Future Is To Create It", so if we can create stuff, then it's possible to (at least partially) predict the future? [6]<p>Futurism or Future Studies [7]<p>[1] <a href="https://www.bbc.com/reel/video/p04s223f/physics-suggests-that-the-future-has-already-happened" rel="nofollow">https://www.bbc.com/reel/video/p04s223f/physics-suggests-tha...</a><p>[2] <a href="https://quantum.phys.cmu.edu/CHS/histories.html" rel="nofollow">https://quantum.phys.cmu.edu/CHS/histories.html</a><p>[3] <a href="https://www.frontiersin.org/articles/10.3389/fpsyg.2013.00131/full" rel="nofollow">https://www.frontiersin.org/articles/10.3389/fpsyg.2013.0013...</a><p>[4] <a href="https://www.wired.com/story/algorithmic-prophecies-undermine-free-will/" rel="nofollow">https://www.wired.com/story/algorithmic-prophecies-undermine...</a><p>[5] <a href="https://projects.iq.harvard.edu/predictionx/week-3-free-will-determinism-and-predictability" rel="nofollow">https://projects.iq.harvard.edu/predictionx/week-3-free-will...</a><p>[6] <a href="https://quoteinvestigator.com/2012/09/27/invent-the-future/" rel="nofollow">https://quoteinvestigator.com/2012/09/27/invent-the-future/</a><p>[7] <a href="https://en.wikipedia.org/wiki/Futures_studies" rel="nofollow">https://en.wikipedia.org/wiki/Futures_studies</a>
> In effect, all the energy the black hole sees over the lifetime of the universe hits the Cauchy horizon at the same time, blasting into oblivion any observer who gets that far.<p>I don't understand that. It sounds as if the reason all the stuff reaches the horizon "at the same time" is because time slows to a stop at the horizon. But doesn't that also apply to the "observer who gets that far"? How can the observer overtake all the other stuff?<p>Maybe I should stay clear of articles dealing with GR; I'm clearly not clever enough to understand them.
> In the real world, your past uniquely determines your future. If a physicist knows how the universe starts out, she can calculate its future for all time and all space.<p>No (or only in very special configurations). See for example the n-body problem.[1]<p>[1] <a href="https://en.wikipedia.org/wiki/N-body_problem" rel="nofollow">https://en.wikipedia.org/wiki/N-body_problem</a>
So let me get this straight... you enter the event horizon of a black hole, from which nothing can escape. This "frees" you from your deterministic past so that you have infinite possible futures... but since you're in a black hole these infinite futures all probably occur in the ultrahot ultrasqueezy confines of a black hole.
Ok no scientific basis for this at all but I often wonder if some future inventions are so potent that their "gravity" for lack of a better word, manifests itself into being.