
Newfound Wormhole Allows Information to Escape Black Holes - digital55
https://www.quantamagazine.org/newfound-wormhole-allows-information-to-escape-black-holes-20171023/
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platz
This is the "traversable" part: throw a qubit into black hole A. Measure a
particle of its Hawking radiation & transmit the result of the measurement
_through the external universe_ to the other black hole B; then use this
knowledge to operate on a Hawking particle coming out of black hole B to
"reconstruct" the original qubit.

~~~
ars
> throw a qubit into black hole A

This would take infinite time (from the POV of the external observer), so I'm
unclear how this is supposed to work.

~~~
pdonis
_> This would take infinite time (from the POV of the external observer)_

No, that's not correct. What is correct is that, in the idealized case where
the hole is eternal (i.e., it never evaporates), it would take an infinite
time for the external observer to _see_ the qubit cross the horizon. But the
qubit reaches the horizon and crosses it in a finite time.

~~~
ars
But we are talking about an external observer - so how is this traversable
plan going to work?

~~~
tinix
It's not, because this is all theoretical. Not a single thing here has ever
been proven experimentally. Black holes do not exist, nor does hawking
radiation.

~~~
whiskers08xmt
There's no direct proof yet, but we have detected the magnetic fields that
theories predict, and of course observe the gravitational effects. The Event
Horizon Telescope[0] will probably deliver something more tangible by 2018.
[0][http://www.nature.com/news/how-to-hunt-for-a-black-hole-
with...](http://www.nature.com/news/how-to-hunt-for-a-black-hole-with-a-
telescope-the-size-of-earth-1.21693)

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mankyd
When the call a wormhole "traversable" does this mean that an macroscopic
object can actually survive a wormhole intact? Or are the referring to
something more along the lines of a sub-atomic particle?

edit: the article eventually starts talking about "qubits" explicitly, so I am
assuming this is sub-atomic particles only unless someone knows more.

Even more specifically, it says that which falls into A comes out of B as
Hawking radiation. You can then transfer an external message (at the speed of
light) between A and B to turn that Hawking radiation into the original object
via hand-wavy quantum teleportation. I get the feeling that you'd have to trap
_all_ of the relevant, escaping radiation from B to actually reconstruct your
object.

~~~
ztjio
It's important to understand when physicists talk about the theoretical
perfect preservation of information in these contexts, it's like... if you
could pause the universe and evaluate every particle, every "thing," all at
once you could understand where it all came from and know the previous step
and from there the previous step and so on infinitely until the "beginning."
The idea being that the entire universe's "state" if you will, is derived
continuously from its origin, observably.

It's not about whether you as a human could use a black hole as a cosmic...
blackboard.

~~~
SubiculumCode
In an entirely mechanistic nonprobabilistic universe, where state C always
follows state B, which always follows state A, etc, then if State X ever
equals a prior state, say state B, then the universe enters into an infinite
loop. A-B-C-D-X-C-D-X...

~~~
tempestn
That's true, but why is it important?

~~~
SubiculumCode
As constructed, it is true. But important? Probably not. Even if the universe
was total mechanistic, and should be described as a series of discrete states,
the probability of ever entering into identical states would be very near
zero, except perhaps in some hypercooled state, or something. am not sure that
the laws o thermodynamics would even allow that to happen. But I am no
physicist..just a dude, who had a thought.

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platz
I believe Susskind was of the opinion that that one could create an ER=EPR
wormhole between two entangled black holes, and that jumping into one of the
black holes would allow one to access the wormhole, and meet someone "in the
middle" who had jumped into the other wormhole, but it would be impossible
after that for either person to get out of the wormhole.

Additionally, because the entropy of the wormhole increases with time, the
"length" of the wormhole seems to also increase with time.

~~~
philipov
A black hole is a fast scrambler and very quickly comes to thermal equilibrium
(max entropy). However, the complexity continues to increase long after
thermal equilibrium, and that's what is thought to be analogous to the length
of the wormhole growing (at the speed of light, no less).

[0]:
[https://www.youtube.com/watch?v=9crggox5rbc&t=1202s](https://www.youtube.com/watch?v=9crggox5rbc&t=1202s)

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mirimir
Doesn't "Newfound Wormhole Allows Information to Escape Black Holes" rather
strain the meaning of "found"? I get that it's "found" in a mathematical
sense. But in a physical sense, it's more like "possible".

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creep
I KNEW IT

~~~
dang
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gt_
Some of the better political safire I’ve read in while.

