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The Most Famous Paradox in Physics Nears Its End
Quanta Magazine ^ | 29 October 2020 | George Musser

Posted on 10/30/2020 3:38:08 AM PDT by Candor7

......................................And that led to a remarkable twist in the story. Because the radiation is highly entangled with the black hole it came from, the quantum computer, too, becomes highly entangled with the hole. Within the simulation, the entanglement translates into a geometric link between the simulated black hole and the original. Put simply, the two are connected by a wormhole. “There’s the physical black hole and then there’s the simulated one in the quantum computer, and there can be a replica wormhole connecting those,” said Douglas Stanford, a theoretical physicist at Stanford and a member of the West Coast team. This idea is an example of a proposal by Maldacena and Leonard Susskind of Stanford in 2013 that quantum entanglement can be thought of as a wormhole. The wormhole, in turn, provides a secret tunnel through which information can escape the interior.

Theorists have been intensely debating how literally to take all these wormholes. The wormholes are so deeply buried in the equations that their connection to reality seems tenuous, yet they do have tangible consequences. “It’s hard to answer what’s physical and what’s unphysical,” said Raghu Mahajan, a physicist at Stanford, “because there’s something clearly right about these wormholes.”

But rather than think of the wormholes as actual portals sitting out there in the universe, Mahajan and others speculate that they are a sign of new, nonlocal physics. By connecting two distant locations, wormholes allow occurrences at one place to affect a distant place directly, without a particle, force or other influence having to cross the intervening distance — making this an instance of what physicists call nonlocality. “They seem to suggest that you have nonlocal effects that come in,” Almheiri said. In the black hole calculations, the island and radiation are one system seen in two places, which amounts to a failure of the concept of “place.” “We’ve always known that some kind of nonlocal effects have to be involved in gravity, and this is one of them,” Mahajan said. “Things you thought were independent are not really independent.”

At first glance, this is very surprising. Einstein constructed general relativity with the express purpose of eliminating nonlocality from physics. Gravity does not reach out across space instantly. It has to propagate from one place to another at finite speed, like any other interaction in nature. But over the decades it has dawned on physicists that the symmetries on which relativity is based create a new breed of nonlocal effects.

This past February, Marolf and Henry Maxfield, also at Santa Barbara, studied the nonlocality implied by the new black hole calculations. They found that the symmetries of relativity have even more extensive effects than commonly supposed, which may give space-time the hall-of-mirrors quality seen in the black hole analyses.

All this reinforces many physicists’ hunch that space-time is not the root level of nature, but instead emerges from some underlying mechanism that is not spatial or temporal. To many, that was the main lesson of the AdS/CFT duality. The new calculations say much the same thing, but without committing to the duality or to string theory. Wormholes crop up because they are the only language the path integral can use to convey that space is breaking down. They are geometry’s way of saying the universe is ultimately nongeometric. The End of the Beginning

Physicists not involved in the work, or even in string theory, say they are impressed, if duly skeptical. “Hats off to them, since those calculations are highly nontrivial,” said Daniele Oriti of the Ludwig Maximilian University of Munich.

But some feel uneasy about the tottering pile of idealizations used in the analysis, such as the restriction of the universe to less than three spatial dimensions. The previous wave of excitement over the path integral in the ’80s, driven by Hawking’s work, fizzled out in part because theorists were unnerved by the accumulation of approximations. Are today’s physicists falling into the same trap? “I see people make the same hand-waving arguments that were made 30 years ago,” said Renate Loll of Radboud University in the Netherlands, an expert on the gravitational path integral. She has argued that wormholes need to be expressly forbidden if the integral is to give sensible results.

Skeptics also worry that the authors have overinterpreted the replica trick. In supposing that replicas can be connected gravitationally, the authors go beyond past invocations of the maneuver. “They are postulating that all geometries connecting different replicas are allowed, but it’s not clear how that fits into the framework of quantum rules,” said Steve Giddings of Santa Barbara.

Given the uncertainties of the calculation, some are unconvinced that a solution is available within semiclassical theory. “There’s no good choice if you restrict to quantum mechanics and gravity,” Warner said. He has championed models in which stringy effects prevent black holes from forming in the first place. But the upshot is broadly similar: Space-time undergoes a phase transition to a very different structure. Related:

Hologram Within a Hologram Hints at Fate of Black Holes The Fuzzball Fix for a Black Hole Paradox Wormholes Reveal a Way to Manipulate Black Hole Information in the Lab Wormholes Untangle a Black Hole Paradox

Skepticism is warranted if for no other reason than because the recent work is complicated and raw. It will take time for physicists to digest it and either find a fatal flaw in the arguments or become convinced that they work. After all, even the physicists behind the efforts didn’t expect to resolve the information paradox without a full quantum theory of gravity. Indeed, they thought the paradox was their fulcrum for prying out that more detailed theory. “If you had asked me two years ago, I would have said: ‘The Page curve — that’s a long way away,’” Engelhardt said. “We’re going to need some kind of [deeper] understanding of quantum gravity.’”

But assuming that the new calculations stand up to scrutiny, do they in fact close the door on the black hole information paradox? The recent work shows exactly how to calculate the Page curve, which in turn reveals that information gets out of the black hole. So it would seem as though the information paradox has been overcome. The theory of black holes no longer contains a logical contradiction that makes it paradoxical.

But in terms of making sense of black holes, this is at most the end of the beginning. Theorists still haven’t mapped the step-by-step process whereby information gets out. “We now can compute the Page curve, and I don’t know why,” said Raphael Bousso at Berkeley. To astronauts who ask whether they can get out of a black hole, physicists can answer, “Sure!” But if the astronauts ask how to do it, the disquieting reply will be: “No clue.”


TOPICS: Astronomy; Science; Weird Stuff
KEYWORDS: astronomy; blackhole; darkenergy; darkforce; darkmatter; entropy; hawking; informationparadox; physics; science; speedofdark; stringtheory
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To: Phlap

1.414........ is it not


21 posted on 10/30/2020 6:16:47 AM PDT by bert ( (KE. NP. N.C. +12) t Zip-a-dee-doo-dah, zip-a-dee-ay My, o. h, my, what a wonderful day)
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To: 6SJ7; AdmSmith; AFPhys; Arkinsaw; allmost; aristotleman; autumnraine; bajabaja; ...


· List topics · post a topic · subscribe · Google ·

22 posted on 10/30/2020 7:00:52 AM PDT by SunkenCiv (Imagine an imaginary menagerie manager imagining managing an imaginary menagerie.)
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To: Candor7

Wazzat?


23 posted on 10/30/2020 7:35:04 AM PDT by libertylover (Election 2020: Make America Great Again or Burn it to the Ground. Choose one.)
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To: bert


24 posted on 10/30/2020 9:39:40 AM PDT by Chode (Send bachelors and come heavily armed.)
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To: JudgemAll

Agreed 100%.
Case in point is the silliscience claims about atmospheric CO2 levels causing climate change. Pure silliness.
The “scientists” have their climate model upside down (to climate alarmists: the atmosphere is NOT the controlling mechanism in climate), and consequently all their theories and suppositions are nonsensical.
Climate is a thermodynamic system, and the atmosphere is too flimsy to contain thermal content for long - a couple of days, at best.


25 posted on 10/30/2020 9:44:42 AM PDT by Montana_Sam (Truth lives.)
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To: JudgemAll

+++


26 posted on 10/30/2020 11:07:38 AM PDT by SuperLuminal (Where is Sam Adams now that we desperately need him)
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To: Candor7

I thought the wave particle duality was the most famous paradox in physics.


27 posted on 10/30/2020 11:09:33 AM PDT by discostu (Like a dog being shown a card trick)
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To: Candor7

I thought Daffy and Donald were the most famous paradox in the universe.


28 posted on 10/30/2020 11:17:36 AM PDT by GreenHornet
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To: Candor7

That’s good but I’ve never grokked this biz about information falling into black holes. I’ve got information Biden’s an imbecile, but gravity doesn’t seem to affect it at all.


29 posted on 10/30/2020 12:26:33 PM PDT by LibWhacker
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To: Fred Nerks

That’s where galaxies go to die.>>>>>>>>>>>

No wonder then that I felt queezy after reading the article.

But will they be able to work further in terms of wormholes?
When galaxies die apparently they are connected to somewhere and somewhen else.


30 posted on 10/30/2020 1:40:37 PM PDT by Candor7 ((Obama Fascism:http://www.americanthinker.com/2009/05/barack_obama_the_quintessentia_1.html))
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To: HighSierra5; Fred Nerks

Black hole anti matters.>>>>>>>>>>>>

The solution of the singularity paradox means many things.

One of those things is:

Black Lives Scatter.

They never make it beyond the singularity event horizon without being reduced to particle information.


31 posted on 10/30/2020 1:49:06 PM PDT by Candor7 ((Obama Fascism:http://www.americanthinker.com/2009/05/barack_obama_the_quintessentia_1.html))
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To: Montana_Sam

Yes. Serious people who study the coming real danger of Solar Minimum. Global warming is not deadly, quite the opposite. Bananas growing in Siberia? That would be great. It is all matter of perception. The world is probably still too cold as we speak.


32 posted on 10/30/2020 2:10:20 PM PDT by JudgemAll (Democrats Fed. job-security in hates:hypocrites must be gay like us or be tested/crucified)
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To: Candor7
When galaxies die apparently they are connected to somewhere and somewhen else.

All that matter is turned back into energy in the process, transformed, resurrected as anti-matter, forming mirror-galaxies; that's where all the negativity comes from that the left feeds on.

33 posted on 10/30/2020 3:50:24 PM PDT by Fred Nerks (fair dinkum!)
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To: Candor7

Thus, a Black Hole is an inverter.


34 posted on 10/30/2020 6:36:24 PM PDT by Fred Nerks (fair dinkum!)
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To: Fred Nerks

that’s where all the negativity comes from that the left feeds on.>>>>>>>>>>>>>>>>>>>>>>>>

So Hell is a real place. LOL.


35 posted on 10/30/2020 11:27:04 PM PDT by Candor7 ((Obama Fascism:http://www.americanthinker.com/2009/05/barack_obama_the_quintessentia_1.html))
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To: Candor7

“...which amounts to a failure of the concept of “place.”...

Does this mean the end of the Electoral college?


36 posted on 10/31/2020 9:50:40 AM PDT by Paladin2
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To: bert
It is undefined(never ending). But to see it Now that is a paradox.
37 posted on 11/02/2020 5:56:20 AM PST by Phlap (REDNECK@LIBARTS.EDU)
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To: GreenHornet

lol


38 posted on 11/02/2020 5:58:14 AM PST by Phlap (REDNECK@LIBARTS.EDU)
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