
Photonic Bell states creation around rotating black holes - ovidiu69
https://arxiv.org/abs/1608.06822
======
n4r9
I studied quantum information/foundations to research level, so may be able to
give some input and obviate some of the wilder interpretations. This paper
isn't directly in my field of interest (don't know much about relativity), so
I'm happy to be corrected if I say something stupid.

You've probably heard that quantum information processing uses the "qubit" as
an information primitive. A qubit is not itself a particle, but a "degree of
freedom" which can be in one of a range of states. This degree of freedom
could be spin, polarization, energy, and so on and so on. Unlike bits, a pair
of qubits can be entangled, which means that their joint state is not
decomposable into a statistical mixture of independent pairs of states.

The paper considers two degrees of freedom associated with photons emitted
from the accretion disks of spinning black holes: polarization and orbital
angular momentum (OAM). Essentially, there are two qubits per photon. After
some reasonable assumptions and calculations we find that the two qubits are
highly entangled; in fact, as entangled as it's possible for two qubits to be.
The author speculates that may be able to detect this by measuring such
photons with modern equipment. I suppose the motivation is that we might be
able to use them for actual information processing tasks (although as far as I
can see there's no benefit to this over preparing entangled qubits ourselves).

That's about it, I think. No time-travel, no communication, but a small point
of interest.

------
Steuard
I haven't read the paper yet (too much to do). But I wonder why it's posted in
the "General Physics (physics.gen-ph)" category rather than under "General
Relativity and Quantum Cosmology (gr-qc)" where most papers with similar
topics are traditionally submitted.

The physics.gen-ph category on arXiv is a little odd, a little uncomfortable,
and hard to describe. Here are a couple of quotes from discusions of arXiv
moderation commenting on it:

"There is one middle option between acceptance and rejection: Dubious papers
can be shunted to a category called “general physics,” or “gen-ph.” At best,
gen-ph is a home for papers that don’t fit neatly into any other category; at
worst, it is a crackpot dumping ground. Either way, it allows moderators to
dodge the drama that comes with out-and-out rejections. For many authors,
though, being relegated to gen-ph is just as galling as being rejected
outright: As one such researcher told Reyes-Galindo, having his paper
reclassified to gen-ph felt like a deliberate attempt to diminish the paper’s
impact." \-- [http://oren365.tech/news/What-Counts-as-
Science](http://oren365.tech/news/What-Counts-as-Science)? (via Google cache)

"Personally, I have never had a problem with the arXiv moderation. I had a
paper reclassified from gen-ph to gr-qc once by a well-meaning moderator,
which is how I learned that gen-ph is the dump for borderline crackpottery.
(How would I have known? I don’t read gen-ph. I was just assuming someone
reads it.)" \-- [http://backreaction.blogspot.com/2016/05/the-holy-grail-
of-c...](http://backreaction.blogspot.com/2016/05/the-holy-grail-of-crackpot-
filtering.html)

EDIT: I don't mean this as direct criticism of this paper, which might
potentially be fantastic and just fit better in the general category for one
reason or another than in gr-qc. (Or, some moderator might have been too
harsh: entirely possible!) But I wanted to share some of the unspoken
background information that many physicists would think about when seeing this
link.

~~~
ovidiu69
After you read the paper, will you share us your thoughts on it, please?!!

------
joshumax
Something to note: More times than not, asking a liberal arts major about how
quantum mechanics works is usually more valid and reputable than the preprint
arXiv

~~~
posterboy
You better had substantiate that claim.

------
acqq
It seems the very author of the paper on the arxiv posted the link here
(ovidiu69 here, Ovidiu Racorean of the paper), and maybe he is willing to
answer some specific questions?

Ovidiu, being a researcher, can you please tell what your scientific CV is,
especially related to the topics of the paper?

I see you've submitted different papers to arxiv:

[https://arxiv.org/find/all/1/au:+Racorean_Ovidiu/0/1/0/all/0...](https://arxiv.org/find/all/1/au:+Racorean_Ovidiu/0/1/0/all/0/1)

Have you had any interactions and/or reactions from the other researchers in
the fields? Have you published somewhere else?

------
messel
The stretch is that in the future blackhole state can be changed and send
information back in time? Not seeing it.

~~~
PakG1
Sorta worked in Interstellar, though perhaps not in the way you're describing.
;)

------
pseud0r
Are they suggesting black holes can be used as quantum computers?

~~~
Y_Y
Absolutely not. You could (if it's true, at a glance it's not terribly
convincing) use this as a probe of curved-space QED (a very difficult field)
or as a method to measure of the spin of black holes (currently done by
different dark magic which isn't very reliable).

------
bencollier49
Good idea for a science fiction story.

~~~
Nursie
My thoughts too.

Perhaps they are talking to each other.. .

Edit -- You and I really are quite alike in thought sometimes. You must come
and visit Southampton sometime now the house is a bit more sorted.

~~~
unixhero
My thoughts too.

No, really! :)

This was ragingly interesting, but outside papers like these I wondered what
the application of this at this stage might be; Great sci-fi could be had, was
my conclusion.

------
evanb
Oh man. Can we change this to
[https://arxiv.org/abs/1608.06822](https://arxiv.org/abs/1608.06822) ? This
"write up" is very bad, and clearly comes from somebody who doesn't really
grasp quantum mechanics, and the connection to QUESS is... not good, although
this paper and that idea share certain buzzwords.

