Photons have mass

[American Patriot]

This is a change....

Science is stranger than Science Fiction sometimes

Photons Are No More Massless Particles: Study

posted by Chesa Castro September 26, 2013 News, Tech & Science
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Photons are no more considered as massless particles. A new research has found under extreme temperatures it behaves like molecules.

A group of scientists from MIT and Harvard universities have created a never-before-seen state of matter that was only found in theory until now and in the realms of science fiction.


Photons are the most basic constituent of light and scientists were exploring its properties. While doing so they managed in creating molecules formed from photons bound together. Until now it was thought the photons particles do not interact with each other, but the new experiment makes the existing believe to be wrong. The new finding will push the frontiers of science now.


In a press release Harvard Professor of Physics Mikhail Lukin said, “Most of the properties of light we know about originate from the fact that photons are massless, and that they do not interact with each other… What we have done is create a special type of medium in which photons interact with each other so strongly that they begin to act as though they have mass, and they bind together to form molecules.”


Lukin said further that when the photon interacts with each other, they push against each other and deflect each other.


Lukin and his team cooled rubidium atoms in a vacuum chamber slightly above absolute zero temperature at which particles do not move. They fired at the cloud and found it did pass through it and exit individually, but only to emerge as single molecule to the other side.

[American Patriot]

Scientists create 'light saber' material with photon-binding technique

By Russell Brandom on September 26, 2013 12:11 pm Email @russellbrandom 38Comments
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Photons are usually thought of as ephemeral, massless particles that rarely interact with each other, but a recent discovery by Harvard and MIT professors may force physicists to rethink that assumption. By pumping atoms into a supercooled vacuum chamber, the project created a non-linear quantum medium in which photons will actually bind to each other, creating a new form of photon-based matter that, as it happens, looks an awful lot like the business end of a light saber.


"Similar to what we see in the movies."


"It's not an in-apt analogy to compare this to light sabers," Harvard physicist Mikhail Lukin told Phys.org. "When these photons interact with each other, they're pushing against and deflecting each other. The physics of what's happening in these molecules is similar to what we see in the movies."


The most immediate applications of the discovery will come not in combat, but in quantum computing, where the new form of light-matter could be used to build more intricate chains of interaction. Light is crucial for the mechanics of quantum computing, but physicists have always been limited by photons' ephemeral nature. With this new medium, in which photons aggressively interact with each other, scientists hope to enable more complex logical circuits that are more analogous to those found in conventional computers.

[American Patriot]

Hot Air:

It’s here: MIT and Harvard build a real lightsaber

posted at 3:06 pm on September 26, 2013 by Katie Pavlich

Get ready Star Wars fans, your biggest dream may have just come true. Scientists at MIT say they’ve created a real lightsaber. Rejoice!

That’s right, researchers at Harvard and Massachusetts Institute of Technology say they have built an actual lightsaber, like the ones used in the Star Wars saga.
Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuleti led the study.
The team of physicists say they have discovered a new kind of matter, using things called “Photonic Molecules.”
They say unlike typical lasers which pass right through each other, these bind together so you can whack them against each other.
They say it all ends up looking like the iconic Jedi weapon.

Throwing this into the political arena, the lightsaber development comes just two days after Republican Senator Ted Cruz quoted Darth Vader from the Senate floor during his 21-hour stand against Obamacare.

[American Patriot]

Scientists pretty much just built a lightsaber

MIT and Harvard researchers make previously theoretical molecule out of photons

Obi-Wan Kenobi and Darth Vader in a lightsaber duel shown in a still from Star Wars: A New Hope.

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Ishmael N. DaroPublished: September 26, 2013, 2:02 pm
Updated: 52 mins ago




This should be exciting news for all the Star Wars geeks who have ever dreamed of slicing open a tauntaun with a lightsaber. Scientists at MIT and Harvard have created a new form of matter that isn’t entirely dissimilar from the famous Jedi weapons.


Photons, the basic building blocks of light, are massless and don’t interact with each other normally. So if you cross the beams from two flashlights, the light just passes through the intersection. But the research team found that when they passed photons through a super-cooled vacuum chamber, they could make them clump together into a new form altogether.


“What we have done is create a special type of medium in which photons interact with each other so strongly that they begin to act as though they have mass, and they bind together to form molecules,” Harvard Professor of Physics Mikhail Lukin told phys.org in an interview published Thursday.


Luking co-led a research team with MIT physics professor Vladan Vuletic that just published its results in the latest issue of the journal Nature.


Lukin said that although this kind of reaction has been discussed as theoretically possible, it has never actually been observed before.


“It’s not an in-apt analogy to compare this to lightsabers,” said Lukin. “When these photons interact with each other, they’re pushing against and deflect each other. The physics of what’s happening in these molecules is similar to what we see in the movies.”


Although the discovery is only a proof of concept at the moment, it could have future implications for making quantum computers whose information is contained in light pulses instead of electrical pulses. Lukin also suggested three-dimensional structures – such as crystals – could one day be made entirely out of light.


Whether that will lead to any epic lightsaber fights remains to be seen.


“What it will be useful for we don’t know yet, but it’s a new state of matter, so we are hopeful that new applications may emerge as we continue to investigate these photonic molecules’ properties,” Lukin said.

[American Patriot]

I don't see a "light saber".

I see a "photon torpedo"... or better a "photon bullet" or "shell".

Shot at near the speed of light, a Photon Bomb hitting an object would obliterate anything in its path. This is a TRUE Science Fiction model for a "photon bomb" in space to take on aliens, or blast star ships, or destroy planets.

[American Patriot]

Public release date: 25-Sep-2013
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Contact: Peter Reuell
preuell@fas.harvard.edu
617-496-8070
Harvard University
Seeing light in a new light

Scientists create never-before-seen form of matter

Harvard and MIT scientists are challenging the conventional wisdom about light, and they didn't need to go to a galaxy far, far away to do it.


Working with colleagues at the Harvard-MIT Center for Ultracold Atoms, a group led by Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuletic have managed to coax photons into binding together to form molecules – a state of matter that, until recently, had been purely theoretical. The work is described in a September 25 paper in Nature.


The discovery, Lukin said, runs contrary to decades of accepted wisdom about the nature of light. Photons have long been described as massless particles which don't interact with each other – shine two laser beams at each other, he said, and they simply pass through one another.


"Photonic molecules," however, behave less like traditional lasers and more like something you might find in science fiction – the light saber.


"Most of the properties of light we know about originate from the fact that photons are massless, and that they do not interact with each other," Lukin said. "What we have done is create a special type of medium in which photons interact with each other so strongly that they begin to act as though they have mass, and they bind together to form molecules. This type of photonic bound state has been discussed theoretically for quite a while, but until now it hadn't been observed.


"It's not an in-apt analogy to compare this to light sabers," Lukin added. "When these photons interact with each other, they're pushing against and deflect each other. The physics of what's happening in these molecules is similar to what we see in the movies."


To get the normally-massless photons to bind to each other, Lukin and colleagues, including Harvard post-doctoral fellow Ofer Fisterberg, former Harvard doctoral student Alexey Gorshkov and MIT graduate students Thibault Peyronel and Qiu Liang couldn't rely on something like the Force – they instead turned to a set of more extreme conditions.


Researchers began by pumped rubidium atoms into a vacuum chamber, then used lasers to cool the cloud of atoms to just a few degrees above absolute zero. Using extremely weak laser pulses, they then fired single photons into the cloud of atoms.


As the photons enter the cloud of cold atoms, Lukin said, its energy excites atoms along its path, causing the photon to slow dramatically. As the photon moves through the cloud, that energy is handed off from atom to atom, and eventually exits the cloud with the photon.


"When the photon exits the medium, its identity is preserved," Lukin said. "It's the same effect we see with refraction of light in a water glass. The light enters the water, it hands off part of its energy to the medium, and inside it exists as light and matter coupled together, but when it exits, it's still light. The process that takes place is the same it's just a bit more extreme – the light is slowed considerably, and a lot more energy is given away than during refraction."


When Lukin and colleagues fired two photons into the cloud, they were surprised to see them exit together, as a single molecule.


The reason they form the never-before-seen molecules?


An effect called a Rydberg blockade, Lukin said, which states that when an atom is excited, nearby atoms cannot be excited to the same degree. In practice, the effect means that as two photons enter the atomic cloud, the first excites an atom, but must move forward before the second photon can excite nearby atoms.


The result, he said, is that the two photons push and pull each other through the cloud as their energy is handed off from one atom to the next.


"It's a photonic interaction that's mediated by the atomic interaction," Lukin said. "That makes these two photons behave like a molecule, and when they exit the medium they're much more likely to do so together than as single photons."


While the effect is unusual, it does have some practical applications as well.


"We do this for fun, and because we're pushing the frontiers of science," Lukin said. "But it feeds into the bigger picture of what we're doing because photons remain the best possible means to carry quantum information. The handicap, though, has been that photons don't interact with each other."


To build a quantum computer, he explained, researchers need to build a system that can preserve quantum information, and process it using quantum logic operations. The challenge, however, is that quantum logic requires interactions between individual quanta so that quantum systems can be switched to perform information processing.


"What we demonstrate with this process allows us to do that," Lukin said. "Before we make a useful, practical quantum switch or photonic logic gate we have to improve the performance, so it's still at the proof-of-concept level, but this is an important step. The physical principles we've established here are important."


The system could even be useful in classical computing, Lukin said, considering the power-dissipation challenges chip-makers now face. A number of companies – including IBM – have worked to develop systems that rely on optical routers that convert light signals into electrical signals, but those systems face their own hurdles.


Lukin also suggested that the system might one day even be used to create complex three-dimensional structures – such as crystals – wholly out of light.


"What it will be useful for we don't know yet, but it's a new state of matter, so we are hopeful that new applications may emerge as we continue to investigate these photonic molecules' properties," he said.

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