June 3, 2010

Spooky Eyes: Using Human Volunteers to Witness Quantum Entanglement

By Charles Q. Choi

The mysterious phenomenon known as quantum entanglement —where objects seemingly communicate at speeds faster than light to instantaneously influence one another, regardless of their distance apart—was famously dismissed by Einstein as "spooky action at a distance." New experiments could soon answer skeptics by enabling people to see entangled pulses of light with the naked eye. Although Einstein rebelled against the notion of quantum entanglement, scientists have repeatedly proved that measuring one of an entangled pair of objects, such as a photon, immediately affects its counterpart no matter how great their separation—theoretically. The current record distance is 144 kilometers, between the Canary Islands of La Palma and Tenerife. Photons make up light—and the fact that scientists regularly entangle these tiny packets of energy raised the possibility that humans might actually be able to observe this effect. Now experiments to shoot entangled photons at the human eye are under development, and should take place later this year. "It's fascinating that entanglement is something we could see with the naked eye—it brings us closer to this strange quantum phenomenon ," notes researcher Nicolas Gisin, a quantum physicist at the University of Geneva in Switzerland Entanglement is measured by creating entangled particles, sending them to different detectors, and seeing how quickly a measurement on one influences the other. The idea for this experiment is simply to replace the photon detectors with human vision. Human retinas are surprisingly sensitive, capable of being triggered by roughly seven photons. And although they only have an efficiency of about 7 percent (of every 100 photons that enter the pupil, only about seven go on to reach the retina) they have a dark count of virtually zero, meaning they generate few if any false positives. "The eye can actually detect single photons, but the signals that light sends to the brain are suppressed unless there are about seven—otherwise you would see flashes of light all the time—even in complete darkness," explains quantum physicist Seth Lloyd of the Massachusetts Institute of Technology. First, Gisin and his colleagues will entangle a pair of photons, and then amplify these signals by entangling each of these photons with another ensemble of, say, 100 photons. In the arrangement they are currently developing, one pulse of photons would then be sent at a person, whereas the other would be sent at a conventional photon detector to test what the volunteer saw, Gisin says. "Although there's no reason to have human eyes on both sides, the final experiments can involve that," he added. Gisin and his colleagues have posted their plans to arXiv.org and submitted the idea for more formal publication in the journal Physical Review A . People should not jump to the conclusion that such experiments will entangle people with machines or other people on a quantum level, Gisin cautions. Rather, "people will see photons that were entangled with each other," he explains. Although conventional photon detectors can already accomplish these results, "it's fascinating from a human point of view—I would always prefer to see a galaxy with my naked eye rather than download a picture from the Internet," says quantum physicist Sandu Popescu at the University of Bristol in England, who did not participate in this research. "Also, it's interesting that no one until now was motivated to consider this kind of detector—you normally want to use the best detector possible, not something like the human eye." Entanglement is usually thought of as a rather fragile phenomenon, he added, and such experiments could highlight that it is robust enough "as to survive a person detecting it—much stronger than people usually appreciate." Lloyd, who also is not part of the Gisin team for these experiments, said that it "would be pretty neat if you can still detect entanglement despite the fact you're using the naked eye, which is an imperfect detector that is pretty lousy." He added: "It's really solid work, and when they do have an experiment with a human, I want to be next on line."

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This Halloween: What Does It Mean To Call Something 'Spooky'?


Leah Donnella

spooky eyes meaning

A runner passes a ghostly sculpture on display between Bondi Beach and Tamarama Beach in Sydney. Peter Parks/AFP/Getty Images hide caption

A runner passes a ghostly sculpture on display between Bondi Beach and Tamarama Beach in Sydney.

So, you're at your friend's elaborately decorated Halloween party. There are cobwebs hanging from the ceiling, bloody handprints on the wall, a frothing potion brewing on the stove. It's creepy! And scary! But is it ... spooky?

Sure, "spook" can refer to a ghost. It can refer to a spy. But as many of us know, it's also, sometimes, a racial slur for black people. One of our Ask Code Switch readers wrote in to ask about the etiquette of using words like spook and spooky.

During this, the season of murder mysteries and haunted hayrides, is it insensitive to say that you were spooked?

On Halloween, Insensitivity Goes Beyond Kimonos And Black Face

On Halloween, Insensitivity Goes Beyond Kimonos And Black Face

So here's the deal: Spook comes from the Dutch word for apparition, or specter. The noun was first used in English around the turn of the nineteenth century. Over the next few decades, it developed other forms, like spooky, spookish, and of course, the verb, to spook.

From there, it seems, the word lived a relatively innocuous life for many years, existing in the liminal space between surprise and mild fear.

It wasn't until World War II that spook started to refer to black people . The black Army pilots who trained at the Tuskegee Institute were referred to as the "Spookwaffe" — waffe being the German word for weapon, or gun. (Luftwaffe was the name of the German air force).

Once the word "spook" was linked to blackness, it wasn't long before it became a recognizable — if second-tier — slur.

But that wasn't the end of the story for spook. The word had a bit of a renaissance in the 1970s, with the release of the novel and classic film, The Spook Who Sat By The Door , by Sam Greenlee .

Both the book and movie tell the fictional story of the first black man recruited and trained by the CIA. That man goes through his training, works for a little while, and then quits his job and moves back to Chicago, where he secretly trains a group of young black "freedom fighters."

What A Thug's Life Looked Like In 19th Century India

What A Thug's Life Looked Like In 19th Century India

The title of the movie, of course, both refers to spook meaning "black person" and spook meaning "spy." And as a satirical piece of literature written by an African-American author in the years following the civil rights movement, the use of "spook" was infused with an extra dose of irony.

Renee Blake is a sociolinguist who studies the way language is used in society, "whether it's based on race, class, gender or the like." She says she doesn't hear the word spook all that often, but she does have two salient reference points for it.

The first is The Spook Who Sat By The Door , and the second is the 2000 book and 2003 movie The Human Stain, by Phillip Roth. His novel tells the story of a professor at a New England college who is forced to resign after he calls two African-American students spooks.

The word spook hasn't just gotten fictional people in trouble. In 2010, Target apologized for selling a Halloween toy called "Spook Drop Parachuters" — literally miniature black figurines with orange parachutes.

In light of all this baggage, I asked Blake what she thought about the use of words like spook and spooky during Halloween. She said that, while it's clear that spook has multiple, distinct meanings, it's still important to think about context.

The way that certain words get attached to particular racial groups is incredibly complicated. ( Take thug , for example .)

"Be thoughtful about the fact that [spook] now might have the connotation of referring to a black person in a disparaging way," Blake says. "If someone says, 'Did you get spooked?' and there are no black people there, then, OK, you mean 'Did you get scared or frightened?' That's fine, I get it."

But once you insert black people into the situation, Blake says, it's important to be more tactful. "We know that the word 'niggardly' doesn't mean a black person, but let's be sensitive. Are you going to use the word niggardly in front of a group of young students in a classroom? No."

So, this Halloween, be a little cautious when it comes to describing your surroundings. And don't be afraid of creeping into the thesaurus for a spooky synonym.

To me, it's more fun to be aghast, bloodcurdled, or spine-chilled than "spooked."

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Definition of spooky

  • fiddle-footed
  • high-strung
  • hyperactive
  • hyperexcitable
  • hyperkinetic

Examples of spooky in a Sentence

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'spooky.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

1854, in the meaning defined at sense 1

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Dictionary Entries Near spooky

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Cite this Entry

“Spooky.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/spooky. Accessed 6 Jan. 2024.

Kids Definition

Kids definition of spooky, more from merriam-webster on spooky.

Nglish: Translation of spooky for Spanish Speakers

Britannica English: Translation of spooky for Arabic Speakers

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