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  • Photons are oddballs.

  • When they're not busy being waves, they're massless particles that can travel at light

  • speed because, well, that's what they are, little packets of light.

  • For decades it was also thought photons didn't interact with each other, but recently researchers

  • have discovered how to bind photons together as though they were molecules.

  • With flashlights, unlike ghostbusting equipment, you can cross the streams all you want.

  • They don't bounce off each other or cause every molecule in your body to explode because

  • photons don't much care for one another.

  • Unless, that is, they're fired through a ultracold cloud of rubidium atoms.

  • When scientists from Harvard and MIT fired a weak laser through a rubidium cloud, they

  • observed photons coming out the other side in pairs and triples.

  • Not only that, but they could tell from how much the photons were oscillating that they

  • weren't just bunched up together coming out of the cloud -- they were bonded, like

  • molecules.

  • Photonic molecules!

  • They could even tell how strong the bond was based on their oscillation frequencies!

  • Before we get too ahead of ourselves, I should tell you that not all of this is new news.

  • Back in 2013, scientists fired a blue laser at ultracold rubidium gas and observed the

  • photons forming pairs when they came out the other side.

  • What's new THIS time are that the photons formed the trios.

  • Scientists weren't sure if it was even possible to form groups of three interacting photons.

  • Turns out it's not only possible, but three photons interact even more strongly than pairs

  • of photons.

  • To explain how this happens, researchers believe that as the photons travel through the rubidium

  • cloud, they're briefly captured by the atoms to form an atom-photon hybrid called a Rydberg

  • polariton.

  • The photon travels from atom to atom doing this, and if two polaritons come across one

  • another, the photons can mingle thanks to their atomic partner.

  • They become entangled, and when they reach the edge of the gas cloud the atoms stay behind

  • while the photons stick together.

  • It's like two shy people being introduced to each other by their more outgoing friends

  • at a party.

  • They'd never approach each other on their own, but once they meet they really hit it

  • off.

  • Apparently, they're even open to adding a third person to the mix.

  • Ok, I'm going to abandon this metaphor before I get in trouble.

  • These new photonic molecules have interesting properties, like taking on a tiny amount of

  • mass, which is crazy when you remember photons by themselves are massless.

  • They also travel about 100,000 times slower than normal, so you know, around a sluggish

  • 10,000 kilometers per hour.

  • What we can DO with these photon molecules remains to be seen.

  • They could make it possible for computer logic gates to use light, instead of inefficiently

  • converting light to electrical impulses and back again like some do now.

  • Or they could be used in quantum computing to carry information, thanks to their entangled

  • state.

  • OR if adding more photons to the mix makes them interact more strongly, maybe it's

  • possible to make entire crystals out of light!

  • Time and more research will tell, so more research is needed.

  • Be the light of our life, take a sec, and subscribe.

  • Speaking of quantum craziness, did you hear scientists teleported stuff to SPACE?

  • A handsome devil talks about it here.

  • While photons in the visible spectrum usually won't interact, very high energy photons

  • have a higher probability of bouncing off one another, a process called gamma-gamma

  • scattering.

  • Thanks for absorbing our photons into your eyeballs.

Photons are oddballs.

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B1 US cloud photon interact atom entangled fired

This New Form of Light Is a Physical Molecule, Here’s How We Made It

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    joey joey posted on 2021/04/13
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