[ExI] Did Scientists Just Detect an Exploding Black Hole?

[John Clark]

On Sun, Mar 29, 2026 at 11:16 AM Jason Resch via extropy-chat <
extropy-chat at lists.extropy.org> wrote:

*> In similar neutrino detections of energetic events, such a supernova,
> all the neutrino detectors on earth lit up at the same time. Would we not
> expect something similar if a nearby black hole evaporated?*


*The short answer is somebody got lucky. The slightly longer answer is that
the neutrino the Mediterranean detector found had an energy of 2.2 *10^17
electron volts, that's more than 30 times as powerful as any neutrino the
south pole detector had ever found even after 14 years of operation, and
the source of that neutrino was in the northern hemisphere; and normally
the south pole detector is most sensitive to neutrinos that originate in
the northern hemisphere because neutrinos are the only thing they can make
it all the way through the Earth so the northern hemisphere signal is very
low noise. However that's for normal neutrinos, but this one was far from
normal. The more energetic a neutrino is the larger its cross-section is
and thus the easier it is for matter to stop; the likelihood of a neutrino
as colossally energetic as 2.2 *10^17 electron volts making it all the way
through the Earth without being absorbed is virtually zero.*

*By a lucky chance the Mediterranean detector happens to be much more
sensitive to neutrinos coming in in a horizontal direction then the south
pole detector is, although when they were designing it I don't imagine the
engineers thought that was an important feature. But it turned out to be
very important because the record shattering neutrino came in at an angle
only 0.6 degrees above the horizon, so the neutrino only needed to
go through 91 miles of air and sea water, and not 8000 miles of rock.*

*John K Clark*









>
> On Sun, Mar 29, 2026, 7:14 AM John Clark via extropy-chat <
> extropy-chat at lists.extropy.org> wrote:
>
>> Explore this gift article from The New York Times. You can read it for
>> free without a subscription.
>>
>> Did Scientists Just Detect an Exploding Black Hole?
>>
>> An underwater observatory recently detected a startlingly energetic
>> cosmic neutrino. One possible cause involves a phenomenon that so far
>> exists only in theory.
>>
>>
>> https://www.nytimes.com/2026/03/27/science/astrophysics-neutrinos-black-holes.html?unlocked_article_code=1.W1A.qWMP.6I2De03QUY8j&smid=em-share
>>
>

>
>
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