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A person should be allowed to dream sometimes, how freaking cool would this be. A block hole right in our neighbourhood, even closer than Alpha Centauri. Just imagine what kind of things can be learned from studying it.
Cool, and absolutely terrifying.
we've only seen a neutron start or black hole born last year for the first time. and we really don't even know which one it was.
https://www.sciencefocus.com/news/birth-of-a-black-hole-witn...
there is a LOT of good experimental observation science left to do . let alone all the 'simulations' we have to run.
the fact is, we know precious little about our own outer solar system let alone black holes, the closest of which we know is 3300 light years away, ---https://en.wikipedia.org/wiki/A0620-00----
this is not even anywhere close to our local area of the galaxy, which is 50-100 light years radius from our sun.
the truth is , while all this science is awesome, we have a proclivity to believe we have more certainty in our knowledge than we do. and no where is this procilivity more often seen as exaggerated , than in astronomy, where the physics of space time and distance work against our understanding reality more than in any other area of study.
Since it's a black hole, it's gravitational effect would be at least as much as the Sun. Is there evidence to support this tug of war?
Black holes do not have more gravity per mass than any other object. Put the other way, if the sun would suddenly change into a black hole without losing a lot of mass, the earth would still follow the exact same orbit.
also the black hole polar jets would be beautiful, imagine a dark sun with two long well lit streamers cutting both ways across the sky. we'd all be dead, but it would be beautiful
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Cool, and absolutely terrifying.
Agree with cool, but not with terrifying. According to the paper, the mass would be ~5-15 M⊕ at a distance of 300-1000AU, so not a threatening object in any way.
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Is there a theoretical limit on the minimum mass of a black hole? It's counter-intuitive to me that something could get dense enough to form a black hole and not have more mass than the Sun, or at least enough mass to steal Pluto.
Small black holes evaporate fairly quickly from Hawking radiation. The rate increases dramatically the smaller the mass. Since the only time primordial black holes would have formed was in the Big Bang there is a lower limit based on the black hole surviving 13.8 billion years. iirc the number is on the order of 10^12 kilograms.
One should not miss Figure 1 of the arXiv preprint, which is, alas, absent from the final PRL. https://arxiv.org/pdf/1909.11090.pdf It is among the rarest journal-article figures in physics. If I'd been asked to referee the paper, I'd have campaigned hard to keep it in.
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Crossing into the event horizon of a black hole has a very profound poetry to it in that you will never be able to communicate back your findings. I find the romance of the destruction of knowledge very intriguing - falling into a black hole is similar to shooting a mathematician in the head in that regard. Great way to go, all things considered.
Not sure if you meant it that way but information actually can't be created or destroyed in quantum mechanics. This is known as the no-hiding theorem [1] which has been experimentally proven and which leads to the black hole information paradox. [2] 1. https://en.wikipedia.org/wiki/No-hiding_theorem 2. ttps://en.wikipedia.org/wiki/Black_hole_information_paradox
Since it's a black hole, it's gravitational effect would be at least as much as the Sun. Is there evidence to support this tug of war?
> While an M⊕ object is too light to be an astrophysical black hole formed by stellar collapse, PBHs arise from over densities in the early universe [15, 16] and as a result can be substantially lighter than M . Normally black holes do have at least the mass of ~1.4 times our sun because they are formed by stellar collapse. That is why here they are considering Primordial Black Holes which a) formed differently and b…