Comment by InDubioProRubio 3 days ago
Stupid question, but between two singularities merging, there is tiny space, with gravitation zeroing out and appearing plank matter being ripped towards one and the other. Can one spot that location in the middle where anti-matter and matter bleed from the nothing on modern telescopes?
> gravitational forces
Gravity is not a force in GR. The spacetime curvature in a spacetime with two black holes that merge is not describable in terms of a simple "gravitational field". Spacetime curvature is a fourth rank tensor with twenty independent components. In vacuum ten of those vanish identically, leaving ten independent components.
> between two singularities merging
Two black holes merging does not mean two singularities merging. The singularity (singular, not plural) is a moment of time that is to the future of all other moments inside the hole. If two black holes merge, there is just one singularity inside the merged hole.
Remember that GR is a model of spacetime, not space. In spacetime, a single black hole looks, heuristically, like a cylinder, and the singularity inside is at the future end of the cylinder. Two black holes merging look, heuristically, like a pair of trousers, and the (one) singularity inside the merged hole is at the future end of the trousers (the "waist").
very good, but I would say (since "light cone" is of such common parlance) that the physical 3d analogous projection would be two slightly overlapping 3d-venn diagram funnels conjoining at an "indefinitely" (asymptotically smaller) small space-time minkowski manifold.
naked singularities themselves, however, do not exist.
> the physical 3d analogous projection would be two slightly overlapping 3d-venn diagram funnels conjoining at an "indefinitely" (asymptotically smaller) small space-time minkowski manifold.
I'm not sure what you mean by this, but it doesn't seem to correspond to any actual physical model that I'm aware of.
both objects have a space cone that is overlapping - since they can observe each other, but also have a small bit they xor can observe, since they are a spatialtime distance apart.
regardless, once they are inside the event horizon, their spacetime ends in a "singularity" - that only they experience, since everyone else just saw an ever-slowing couple of observers that never quite reached the event horizon (to the outside observer, who would eventually be either iron or protons, depending if God had decided if they protons should decay or not yet)
i was just pointing out cone versus cylinder, since the black holes' effect is polynomial af
One odd thing that never occurred to me until now is that two black holes that pass each other at near light speed, if they intersect by even a nanometer, will be guaranteed to merge. That nanometer has to fall into both singularities due to the properties of black holes, so transitively they have to merge. Kind of weird. I'm guessing it would create a bunch of angular momentum and throw out almost all their masses as gravitational waves. Will be a fun experiment for someone in a few hundred years.
> I'm guessing it would create a bunch of angular momentum and throw out almost all their masses as gravitational waves. Will be a fun experiment for someone in a few hundred years.
I'm not a physicist but it sounds to me like a gravitational bomb. I wonder how it will affect its surroundings? Stars being torn apart? I wouldn't like to watch such an experiment in person. Though if someone tried it a couple billions light years away from me, and then sent a video record, I'm all for it. I'd prefer to wait a couple billions years for the record to be downloaded, than to watch an online stream.
Why we should prefer the GR model, which lacks mapping from the model back to physical reality, over a physical explanation? It's clear that GR is wrong in case of black hole, because mass CAN escape black holes[1], while GR says that nothing can escape black hole after crossing of event horizon, because of [internal implementation of their model] nonsense.
[1]: https://news.harvard.edu/gazette/story/2022/10/black-hole-bu...
Regardless of the gravity canceling out in this region (which is more complicated and probably will not happen). The current LIGO and Virgo wouldn't have enough spatial resolution to pinpoint tiny regions between black holes.
To explain what will happen is that gravitational field in region you are describing would have a steep spacetime curvature and a point where it will cancel gravitational forces would be more of a saddle (lagrange point classically) point rather than zero gravity region.
Now you also have quantum fluctuations that now with this strong gravitational field you will have virtual particle - anti particle paris pop in and out of vaccum. This is not going to be only in thia region but all around. Also merging process will enhance this phenomenon but deciding where actually this middle point will be difficult.
Now it would be impossible at least for our current observational tools to have resolution for the scale we are talking about. Event horizon telescope for example is designed to observe areas around singularities on much larger scales that what you are interested in here.
But the interesting part would be If matter and antimatter pairs were produced between merging black holes, they would likely be short-lived. In this intense gravitational environment, any particles created would be rapidly torn apart or accelerated towards one of the black holes. The annihilation of such pairs might emit gamma rays, but this signal would be extraordinarily faint compared to the other high-energy processes occurring during a black hole merge.
So the answer is probably No, at least with our current technology.