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Questions without answers -

It's one of the great unanswered questions: is there life beyond Earth? And if there is, can we assume it's benign, intelligent life? Furthermore, is there any link between extraterrestrial goings-on and an event that supposedly took place in 1943? It was an incident so bizarre that it has generated numerous conspiracy theories ever since.

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Putting the experiment in context -

On October 1, 1943, American armed forces had begun to liberate Italy in the fight against fascism in Europe. But later that month, US government officials would be preoccupied with a situation far closer to home.

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What happened to the USS Eldridge? -

At the Philadelphia Naval Shipyard in Pennsylvania, the USS Eldridge, a destroyer escort, was about to enter the history books as the vessel allegedly made to disappear in what became known as the "Philadelphia Experiment." Image: US Navy

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Disappearance in Philadelphia -

On October 28, the destroyer and its crew are said to have suddenly vanished into thin air. Witnesses later spoke of a weird green-blue glow emanating from her hull just before her disappearance.

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Reappearance in Virginia -

According to those on the ground, the USS Eldridge was then seen in the Norfolk Naval Shipyard in Virginia, 482 km (300 mi) away, before disappearing again and reappearing back in Philadelphia. Image: US Navy

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An eyewitness -

What had just happened? Merchant mariner Carl Allen (1925–1994) is one of those who claimed to have witnessed the paranormal episode, and recounted the event 12 years later. In his words, he was standing on the deck of the liberty ship SS Andrew Furuseth when the Eldridge went AWOL.

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Enough to drive a man insane -

The story, compiled according to Allen's account in classified military documents, tells of the vessel being lost from view for several minutes. When it reappeared, its crew was supposed to have suffered various side effects, including insanity that put some into mental institutions. Alarmingly, others were said to have been fused together with the ship; still alive, but with limbs sealed to the metal.

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Invisible to radar -

Allen believed that what he'd witnessed was an experiment by the US Navy to make warships invisible to radar and thus able to command the oceans against the Axis powers.

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Scientific proof? -

Allen's belief was reinforced by the fact that Albert Einstein (1879–1955) had already attempted to unify his general theory of relativity with electromagnetism. In other words, combining gravity and electromagnetism and harnessing the power of both within some kind of device that could help explain the sudden disappearance of the USS Eldridge.

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Unified field theory -

Einstein called his fascinating but unproven research unified field theory (pictured here explained in a letter sent by the celebrated physicist to his mathematician colleague, Ernst G. Straus).

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Anonymous correspondence -

In early 1956, Allen, using the pseudonym Carlos Miguel Allende, sent a series of letters to Morris K. Jessup, author of the book 'The Case for the UFO.' In one of these, Allende warned Jessup not to investigate the levitation of unidentified flying objects, pointing out the consequences of the near-disastrous Philadelphia Experiment. At the same time, Allende also mailed another copy of Jessop's book to the Office of Naval Research (ONR).

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Is alien interference to blame? -

The copy received by the ONR in Arlington, Virginia, contained various handwritten notes and annotations suggesting that extraterrestrial technology allowed the US government to make breakthroughs in unified field theory.

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The Office of Naval Research takes note -

Believing it was Jessup who'd sent them a copy of his own book, the ONR invited him to Arlington where he was shown the annotated version. A confused Jessup recognized the handwriting as that belonging to the mysterious Allende.

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Self-inflicted death or mysterious demise? -

The ONR, its suspicions sparked by Allende's revelations, began investigating the Philadelphia Experiment. Meanwhile, Jessup, none the wiser as to the real identity of Allende, became obsessed with the experiment and its possible links to alien lifeforms. But on April 30, 1959, Morris K. Jessup was found dead in his car.

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Fact or fantasy? -

Jessup, by now disturbed and despondent, had apparently taken his own life: a hose had been run from the exhaust pipe into a rear window of the vehicle, the author succumbing to toxic fumes. Jessup had attempted to write further books on UFO technology, but his ideas were deemed pure fantasy by his publisher.

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A conspiracy theory? -

Depression was cited as the most likely reason behind his decision to end it all. But a conspiracy theory emerged suggesting he'd been murdered to silence him before revealing more details about the events in Philadelphia.

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The hoax is revealed -

Ten years later in 1969, Carl Allen admitted to the Aerial Phenomenon Research Organization that the Philadelphia Experiment had been a hoax. Most government officials had by then already come to the same conclusion. Nonetheless, it proved a bombshell to those who genuinely believed that a warship had somehow been teleported from one location to another by an extraterrestrial hand.

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Non-existent facts -

Asked why he'd written the false annotations suggesting implementation of alien technology, Allen replied that he'd wanted "to scare the hell out of Jessup." Image: US Navy

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What really happened? -

So what really happened on October 28, 1943? Both the Eldridge and another vessel, the USS Engstrom, were dry-docked in the Philadelphia Naval Yard.

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Classified cargo -

According to Military.com, both ships had classified devices onboard, but neither were built as futuristic invisibility cloaks or teleportation machines designed by aliens.

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Defensive system against U-boats -

Instead, these instruments scrambled the magnetic signatures of ships using the degaussing technique, a process in which systems of electrical cables are installed around the circumference of a ship's hull that when activated cancels out the vessel's magnetic field. This electrical current effectively provided protection from magnetic torpedoes launched from U-boats.

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Electricity in the air -

But what about the strange glow reported by Allen? That has been explained either by an electrical storm, or St. Elmo's Fire, a natural phenomenon in which plasma is created in a strong electric field, giving off a bright, incandescent glow.

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No record -

And perhaps most conclusive of all, records in the Archives Branch of the Naval History and Heritage Command have been repeatedly searched, but no documents have been located that confirm the event, or any interest by the Navy in attempting such an experiment.

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'The Philadelphia Experiment' (1984) -

But that's not quite the end of this mysterious saga. In 1984, 'The Philadelphia Experiment' was released.

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The strange case of Alfred Bielek -

Based on the urban legend, the movie was a so-so effort to recreate the events of 1943. One cinema-goer, a guy called Alfred Bielek, claimed the film reactivated a long suppressed memory of his being on the Eldridge during the teleportation episode.

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Claims of a cover-up -

Apparently one of only two known survivors from that remarkable day, Bielek spoke of the stress he had to deal with as a result of the subsequent cover-up that kept the Philadelphia Experiment under wraps for decades.

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A captive alien? -

But Bielek somewhat lost credibility when he also insisted that the US Navy had in fact captured an alien during the cloaking process.

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The reality of invisibility -

What is real is the fact that invisibility might one day be a reality. By bending light of all wavelengths around an object, irrespective of its shape, both metalenses (flat lens technology) and metamaterials (composite media that can be engineered to exhibit unique electromagnetic properties) offer the potential to effectively "cloak" any object.

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The age of stealth -

And right here, right now, the United States Air Force has in operation its stealth bomber, whose peculiar shape deflects radio beams, thus making detection by radar that much slower and far more difficult.

Sources: (Military.com) (Naval History and Heritage Command)

See also: The remarkable story behind the capture of the German submarine U-505

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