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Traversable Wormholes Can Exist, But They're Not Very Useful For Space Travel, Physicists Say (phys.org)
A new study from physicists at Harvard and Stanford says that wormholes can exist but they're not very useful for humans to travel through. "It takes longer to get through these wormholes than to go directly, so they are not very useful for space travel," said the author of the study, Daniel Jafferis. From the report: Despite his pessimism for pan-galactic travel, he said that finding a way to construct a wormhole through which light could travel was a boost in the quest to develop a theory of quantum gravity. The new theory was inspired when Jafferis began thinking about two black holes that were entangled on a quantum level, as formulated in the ER=EPR correspondence by Juan Maldacena from the Institute for Advanced Study and Lenny Susskind from Stanford. Although this means the direct connection between the black holes is shorter than the wormhole connection -- and therefore the wormhole travel is not a shortcut -- the theory gives new insights into quantum mechanics.
"From the outside perspective, travel through the wormhole is equivalent to quantum teleportation using entangled black holes," Jafferis said. Jafferis based his theory on a setup first devised by Einstein and Rosen in 1935, consisting of a connection between two black holes (the term wormhole was coined in 1957). Because the wormhole is traversable, Jafferis said, it was a special case in which information could be extracted from a black hole. "It gives a causal probe of regions that would otherwise have been behind a horizon, a window to the experience of an observer inside a spacetime, that is accessible from the outside," said Jafferis. The physicists presented their results at the 2019 American Physical Society April Meeting in Denver, Colorado.
"From the outside perspective, travel through the wormhole is equivalent to quantum teleportation using entangled black holes," Jafferis said. Jafferis based his theory on a setup first devised by Einstein and Rosen in 1935, consisting of a connection between two black holes (the term wormhole was coined in 1957). Because the wormhole is traversable, Jafferis said, it was a special case in which information could be extracted from a black hole. "It gives a causal probe of regions that would otherwise have been behind a horizon, a window to the experience of an observer inside a spacetime, that is accessible from the outside," said Jafferis. The physicists presented their results at the 2019 American Physical Society April Meeting in Denver, Colorado.
I decided to try my best to understand what's being proposed here. So I RTFA, then I read the linked articles, then I read the articles supporting those, essentially in an attempt to get to the underlying "proof" or "theory" on which this "new" proposal is built.
Absolutely every single one, without exception, ended up at a wikipedia page that explained [such and such] was a conjecture. No real-world experiments, no measurements, no ACTUAL mathematical theories that ACTUALLY proved anything, just absolute pure conjecture.
Conjecture is, of course, just another word for "guess". Sure, maybe a good guess, and one supported by logic, but a guess nonetheless.
So here's my question. For years, thousands if not hundreds of thousands of people have suggested that wormhole travel is possible, and many of them have "conjectured" that it involves the quantum entanglement of two black holes. Perhaps the smartest of them has even suggested that the method of travel resolves itself so there is no "entanglement overhead". But for sure the "conjecture" that wormhole travel is possible has got to be at least 50 years old.
So.... just because someone who calls themself a physicist makes exactly the same guess - still with absolutely no experimental nor mathematical proof (in the sense of resolvable equations) we're now supposed to say "Oh wow, well done, it must be true!"?
Can anyone with more knowledge than me explain (perhaps in layman's terms) what's actually NEW about this latest guess? And why it has any more weight than the physics of Star Trek, of Interstellar, or even of your average 1950s B Movie?