Facebook to clean up News Feed

Facebook has announced that it is cleaning up its News Feed to weed out spammy posts, so that users of the social networking website don't miss important and relevant stories and to penalize spammers.

Elaborating on the move, Facebook posted on its blog that it's introducing a series of improvements to News Feed to reduce stories that users frequently flag as spam. "Many of these stories are published by Pages that deliberately try and game News Feed to get more distribution than they normally would," said Facebook employees Erich Owens and Chris Turitzin.

Facebook will essentially take steps to counter three kinds of news feed spam - Like-baiting, frequently circulated content and spammy links.

Facebook says "Like-baiting" is when posts explicitly ask readers to like, comment or share the post, to get additional distribution beyond what the post would normally receive. " The improvement we are making today better detects these stories and helps ensure that they are not shown more prominently in News Feed than more relevant stories from friends and other Page," said the Facebook executives.

The update will not impact Pages that are genuinely trying to encourage discussion among their fans, Facebook clarified.

Facebook is also improving News Feed so that it doesn't focus on pages that reshare content as most users do not find such content relevant.

Stories that misguide users into clicking on links to pages that contain only ads or a combination of frequently circulated content and ads, will also be restricted. For instance some stories may claim to link to a photo album but instead take the viewer to a website with just ads, the social networking giant iterated.

"By measuring how frequently people on Facebook who visit a link choose to like the original post or share that post with their friends, we've been able to better detect spammy links," it added. According to Facebook, the update improves News Feed to reduce cases of spammy links, and in early testing it has witnessed a 5% increase in people on Facebook clicking on links that take them off of Facebook.

A device to make your computers faster

Here comes an optical device that may lead to new and more powerful computers that run faster and cooler. 

Researchers at Washington University in St Louis have developed an essential component of new computers that would run on light.

"We believe that our discovery would benefit many other fields involving electronics, acoustics, plasmonics and meta-materials," said Lan Yang, an associate professor of electrical and systems engineering at Washington University.

The team created an optical diode by coupling tiny doughnut-shaped optical resonators - one with gain and the other with loss - on a silicon chip.

This diode is capable of completely eliminating light transmission in one direction and greatly enhancing light transmission in the other nonreciprocal light transmission, explained lead author Bo Peng from Yang's team.

"Coupling of so-called loss and gain devices using PT (parity-time)-symmetry could enable such advances as cloaking devices, stronger lasers that need less input power, and perhaps detectors that could 'see' a single atom," Yang added.

To make the optical diode, the researchers used two micro-resonators positioned so that light can flow from one to the other.

One device is the "lossy" silica resonator. The other incorporates the chemical element erbium into the silica structure for gain.

When the rate of gain in one resonator exactly equals that of loss in the other, the "phase transition" occurs at a critical coupling distance between the resonators.

Simply put, when a "lossy" system is coupled with a "gain" system such that loss of energy exactly equals gain at an equilibrium point, a "phase transition" occurs.

"Our resonators are small enough to use in computers and future optical information processors," Peng noted.

According to Yang, we built our optical diodes from silica which has very little material loss at the telecommunication wavelength. The concept can be extended to resonators made from other materials for better performances.

The PT symmetry concept can be extended to electronics, acoustics and other fields to create one-way channels, and photonic devices with advanced functionalities, said the paper, published in the journal Nature Physics.