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Physicists Theorize Out How To Retrieve Information From a Black Hole (sciencemag.org)
sciencehabit writes: Black holes earn their name because their gravity is so strong not even light can escape from them. Oddly, though, physicists have come up with a bit of theoretical sleight of hand to retrieve a speck of information that's been dropped into a black hole. The calculation touches on one of the biggest mysteries in physics: how all of the information trapped in a black hole leaks out as the black hole 'evaporates.' Many theorists think that must happen, but they don't know how.
Ask a politician or CEO or salesman. They routinely pull information out of a "black hole".
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
It would more impressive if they could retrieve that lab report I did on my Amiga 20 years ago.
Why do they expect information to be conserved in the first place? Information loss is common and you don't even need black holes. A simple example is matter-antimatter collision which turns into two photons, so you lose information about the identify of the original particles.
retrieving your tsa-confiscated laptop.
Put a bigger black hole right next to it and suck everything out.
The radiation coming out of black hole will have lots of particles, normalising any information into practical randomness, hence increasing the entropy of universe. it'd take a hell of an effort to find out which photon will carry the information of electron.
The laws of nature are the source of the information ultimately. At the heat death of the universe, time stops and space disappears, leaving a big bang that expands into a universe with the same laws of nature producing the same information that was lost in the previous incarnation.
> "Quantum teleportation enables two partners, Alice and Bob, to transfer the delicate quantum state of one particle such as an electron to another. In quantum theory, an electron can spin one way (up), the other way (down), or literally both ways at once. In fact, its state can be described by a point on a globe in which north pole signifies up and the south pole signifies down. Lines of latitude denote different mixtures of up and down, and lines of longitude denote the "phase," or how the up and down parts mesh. However, if Alice tries to measure that state, it will "collapse" one way or the other, up or down, squashing information such as the phase. So she can't measure the state and send the information to Bob, but must transfer it intact."
Really all she does is map the limits of the detector onto the electron. She takes a measurement, which is the measuring tools representation of the thing being measured. Not the actual thing itself.
So if I photograph a 3D scene with a camera, the result is a 2D picture. It hasn't made the world 2D, the limits you see in the picture are a result of the limits of the detector. A camera in this case.
QM says she "sets" it by the act of measuring it, but no such proof exists. And this led Einstein to point out the bogus nature of the claim with "spooky action at a distance". Why would the thing care or know about the limits of the detector being used to detect it?
So when I use an electronic detector to measure light, that has the issue that electrons are promoted through fixed energy levels, if it can't promote the electron then it cannot be detected. So that detector will appear to see light as flashes (when it can promote the electron), or dark (when it cannot).
Does the light think "oh.... right I'm in an electronic detector, so I should bunch up to look like particles/photons?" No, of course it doesn't, that's just what light would look like to a detector that can only detect fixed quanta!
And now we get to extremes like the Delft experiment. Where they filter out any experiment result that isn't "entangled" then put it into a Bells test to prove "entanglement". And claim this as a loophole free proof?? Seriously?
for data compression.
Sheesh, evil *and* a jerk. -- Jade
Ignorant amateur here. ISTM that if a virtual pair appears straddling the event horizion, the one that gets away never was inside the black hole to begin with, and thus would not carry away any matter or energy. Isn't the black hole just working as an engine to extract matter/energy from the vacuum near the event horizon? Half of which goes in, making the BH bigger, and half of which escapes to the external universe.
In the unlikely event that that conception is correct, it would be interesting to think about what happens to the vacuum near the event horizion. Does it get depleted of its vacuum energy, or is it an infinite source? If depleted, does vacuum energy flow in from other nearby vacuum to replenish it?
Is the vacuum inside a black hole anything like the external vacuum?
Sheesh, evil *and* a jerk. -- Jade
just go to blackhole.com
Table-ized A.I.
Late again brainiacs!
It's not like there is a lot of experimental evidence here, one way or the other.
If you reversed time, those photons would head back to the place from the particle collision they started and undo the thing to form the particles.
So for information to be destroyed, there would be points in time, where you cannot reverse time and undo the thing mathematically.
So your equation describing the process, would have to work when t=0, t=1, t=2, t=3, t=4 (heading forwards) and yet fail when heading back, e.g. t = 4, t=3, (fail) because between t=2 and t=3 information was destroyed so you cannot reverse time further. (reverse time mathematically in equations not in real life).
So information is conserved because no such mechanism has ever been found. In terms of common sense that would be the case.
(Don't confuse the information with the measurement of that information, you might not be able to measure it well enough to reconstruct the original, but that is a different issue, the data is there, its just our measurement limitation.)
The black hole conjecture was that all that information is trapped behind the event horizon and cannot be retrieve (which would break entanglement, how can the entangled particle, paired to one falling into a black hole, be set by interactions in a black hole if its inside the event horizon when information cannot escape, i.e. entanglement is bogus) .
Hawkins solution to an equation suggested some radiation could escape a black hole. But if stuff can escape then the "all info trapped behind the event horizon" conjecture is false.... but that seems to have been ignored an they went on and did conjectures assuming both Hawkins is true and Event Horizon limit on info is true and conjectured a bunch of other stuff.
Here the QM entanglement guys hypothesize ways around the issue to fixup QM.
It's really conjecture on arbitrary selections of conflicting conjectures, more about budgets than science.
Does that get information, or just data?
Physicists Theorize Out
Did they theorize the shit out of this thing?
systemd is Roko's Basilisk.
Attempting to calculate predictions in extreme situations from well tested theories (GR in this case) is a good way to find potential conflicts, either with the theory itself, or with other well tested theories (e.g. QFT and statistical mechanics). Looking for new ways to potentially falsify a theory and/or see if it fails to connect to a diverse set of observations is pretty solid science. Even if you are examining conditions so extreme that they are not physically creatable or observable in the real world, you can still find contradictions that give hints (or more) toward finding the limits of the regimes where the theory is applicable. Those limits may be much more approachable than the thought experiments that suggested where to look.
There was literally a Star Trek novel written around this as an idea.
http://memory-alpha.wikia.com/wiki/The_Buried_Age
It's about Picard's adventures in the 10 years between losing the Stargazer and finally coming aboard the Enterprise.
Why don't they use water-boarding? It works so well, as we all know.
/dev/null earns its name because the device is so small nothing can be read from it. Oddly, though, physicists have come up with a bit of theoretical sleight of hand to retrieve a speck of information that's been sent to /dev/null. The calculation touches on one of the biggest mysteries in physics: how all of the information written to /dev/null hole leaks out as heat from the CPU and gets 'dispersed' by the heat sink. Many theorists think that happens, but they don't know how to put humpty dumpty together again.
We are living inside a black hole
It is evaporating
Happy New Year
They know all about information black holes, seeing as how they are one.
dd if=/dev/blackhole of=/tmp/data ?
Thinking about information this way is wrong. Information is not real, it is a derivative of the imagined transportation of matter through space and compression beyond the event horizon. Quantum teleportation is equally a mistake. There is no transport of information. There may be vacuum fluctuations due to the lower density in space around the black hole..
Call me when there is an experiment to back it up. Otherwise it is just speculation.
putting the 'B' in LGBTQ+
fox news emits no information.
Some drink at the fountain of knowledge. Others just gargle.
Of the information loss paradox and various fixes. The "holographic universe" is another fix. That is copy of information inside the BH exists imprinted on the event horizon.
The Akashic record has to be somewhere!
Or "guess". But not "theorize". Ah, the pain.