
Physicist Proposes Alternative to Black Holes - jkmcf
http://www.skyandtelescope.com/astronomy-news/physicist-proposes-new-black-hole-alternative/
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jepler
At risk of sounding like those armchair physicists on the internet (oh wait,
that's exactly how this post sounds!) it's "obvious" that a black hole cannot
form.

The standard lay explanation of what an observer outside a black hole sees as
an object falls into it is that gravitational time dilation freezes the object
just at the event horizon. "[A]n object falling into a black hole appears to
slow as it approaches the event horizon, taking an infinite time to reach
it.[62]" (wikipedia citing Carroll 2004). For an object with just short of
black hole mass, this time would instead be just short of infinite. So how
does the black hole finish forming? (A similar problem seems to apply in the
interior, where hawking radiation evaporates the black hole mass after
essentially no time has passed for the observer falling inward)

Changing argumentative tactics to something totally nonphysical and unrelated
to black holes except by sharing the term "singularity", this feels to me like
a function such as f(x) = 1/x or f(x) = -ln x as you approach x=0. Yes, if you
can get all the way to x=0 you're at a singularity. But if you're riding the
curve on your bicycle, the distance you've got to ride along the curve is
infinite, so you can never experience this supposed singularity after a finite
time.

This armchair viewpoint is obviously flawed in some way, or real
astrophysicists wouldn't be talking about actual black holes like they
existed, so I'd love to hear an explanation that tackles this specific
objection.

