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Black hole singularity is a surface not a point

arxiv.org

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Re: Black hole singularity is a surface not a point

#12

Should be pointed out that this is a critique of common popsci journalism tropes and not a fancy new research result. Anyone who has taken a graduate level class in General Relativity would have been able to tell you the same.

Or read Susskind's "The Theoretical Minimum: General Relativity". For a non-spinning blackhole at least, not only is the singularity not a point, it is a surface in time, not space (as the book explains, the space and time coordinates switch places as you cross the event horizon).

Re: Black hole singularity is a surface not a point

#15
post #13

How does one descr blackhole to a non-physicist without losing much accuracy? I just it of a very-dense-object.

The problem there is that not even the physicists completely agree on the details, because we know black holes definitely exist, but every explanation breaks one rule or another that should apply from different disciplines. It's part of why they get so much ongoing attention.

Re: Black hole singularity is a surface not a point

#16
post #13

How does one descr blackhole to a non-physicist without losing much accuracy? I just it of a very-dense-object.

The problem there is that not even the physicists completely agree on the details, because we know black holes definitely exist, but every explanation breaks one rule or another that should apply from different disciplines. It's part of why they get so much ongoing attention.

Black holes are essentially where our knowledge of spacetime breaks, and we can’t even see into it. It’s hard to really concretely know much about it directly.

Re: Black hole singularity is a surface not a point

#17
post #6

what's really going to blow your mind is while you probably assumed or knew spinning black holes move space around them spinning black holes also move TIME around them * https://www.science.org/doi/10.1126/sciadv.ady9068 so in theory a spinning black hole that's been around for billions of years has a time drag around it in a path that is billions of years old (no we can't navigate it because yes that would be time t…

Consider the magnetar.

https://en.wikipedia.org/wiki/Magnetar

"A magnetar's 10^10 tesla field, by contrast, has an energy density of 4.0×1025 J/m3, with an E/c2 mass density more than 10,000 times that of lead."

Re: Black hole singularity is a surface not a point

#19
Well... yeah? That's describing the event horizon. It's a term roughly as widely used as "singularity".

Talking about the inside of a black hole is indeed rather pop-misunderstood though, yes. But it's not like physicists are especially confident about the details either. Theoretical astrophysics changes a lot as time goes on and our instruments improve, and it's a rather hard field to do experiments on to get better data quicker.

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