user: Lightsaber critics say the one in the Star Wars teaser could never work. They’re wrong.

The first teaser trailer of "Star Wars: The Force Awakens," the Disney-backed feature directed by J.J. Abrams, which opens in theaters Dec. 18, 2015. (Disney)

The new Star Wars trailer has only been out for a couple of hours, and while it's getting mostly positive feedback, there's one moment in particular that keeps attracting attention: The part where a Sith turns on a lightsaber, and then turns on two other lightsabers that act as a crossguard of some kind.

The crossguard idea purports to solve the problem of an opposing lightsaber sliding down and hitting the defender's hand. Some, like The Verge's T.C. Sottek, argue that even if this is a concern, the way it's been implemented here doesn't actually protect the hand.

As anyone who's watched the Star Wars movies knows, lightsabers can cut through pretty much anything — including other lightsabers, as when Obi-Wan Kenobi sliced Darth Maul's double lightsaber in half. So the fact that the crossguard saber leaves a bit of room for an enemy lightsaber to come slicing through the emitter seems to defeat the whole point of the crossguard. And that's silly.

But hang on. There just may be an explanation for this that makes the crossguard a little less implausible than it might seem.

In the Star Wars universe, there are certain rare materials that are thought to be lightsaber-resistant. Among these are substances like phrik, cortosis and Mandalorian iron, which have been used to create weapons and armor that can deflect or short-circuit lightsaber beams. There's a precedent for lightsabers made of phrik: Emperor Palpatine's lightsaber was, according to Star Wars: Revenge of the Sith: The Visual Dictionary. In Star Wars video games, cortosis has been shown to block lightsabers, and sometimes shut them down.

Maybe J.J. Abrams has really done his homework on Star Wars technology. Maybe what he's telling us is that this Sith saber is made of one of these resistant materials.

Okay, probably not. It's more likely the producers just made a silly design choice. And of course, even if the crossguard emitters were made of cortosis, why not just make the whole crossguard out of it, too? Seems like that would be easier.

But until I'm proven otherwise, I'm going to assume the Sith have figured out how to manufacture lightsabers with superpowers.

(Related: Master bladesmith: New lightsaber design is a terrible idea)

Brian Fung covers technology for The Washington Post.

Summary: You just need to get creative with these rare materials.


France Opens Manslaughter Investigation

(PARIS) — French authorities opened a manslaughter inquiry Monday into the May crash of an EgyptAir plane that killed 66 people, saying there is no evidence so far to link it to terrorism.

Prosecutor’s office spokesman Agnes Thibault-Lecuivre said the inquiry was launched as an accident investigation, not a terrorism investigation. She said authorities are “not at all” favoring the theory that the plane was downed deliberately, though the status of the inquiry could eventually change if evidence emerges to that effect.

Investigators decided to start the probe before waiting to analyze the plane’s flight data and voice recorders, based on evidence gathered so far, she said, without elaborating.

EgyptAir Flight 804, an Airbus A320 en route from Paris to Cairo, slammed into the Mediterranean on May 19. The reason for the crash remains unclear. The pilots made no distress call, and no group has claimed to have brought down the aircraft.

Search teams have recovered its two flight recorders, but they suffered damage and Egyptian investigators were unable to download information from the so-called black boxes. The recorders’ memory cards arrived Monday in Paris, Egyptian investigators said. Technicians at France’s air accident investigation agency, the BEA, will attempt to clean and repair them, and then send them back to Egypt for analysis, the BEA said in a statement Friday.

While the plane was Egyptian and crashed in Egyptian waters, France can also investigate because the plane was manufactured by France-based Airbus and French citizens were among those killed.

Summary: Authorities say there is no evidence so far to link the crash to terrorism


Who's Behind That Political Ad? This App Tells You

You know the ultra-useful Shazam and SoundHound apps that let you hold your cellphone up to a speaker to instantly identify the song title and artist? A new app released Wednesday is doing exactly the same thing — but for political ads instead of music.

Called “Super PAC App,” the app uses audio recognition technology to identify political advertisements. Then, it provides users with a wealth of information about the ad: What campaign or organization made it, how much it cost and how accurate the claims made in the ad actually are. It also lets users rate the ads with a variety of responses, including “love,” “fair,” “fishy” and “fail.”

Curious users can also use the app to check out political ads being run in other states — Iowans can check in on Ohio, New Yorkers can get a feel for the message being pushed in Florida, and so on.

Super PAC App was created by Jennifer Hollett and Dan Siegel, and is the product of a class project at MIT’s Media Lab. The pair are hoping the app builds an engaged community around the app, full of users submitting new ads they’ve spotted on the web or on TV.

“The goal is to get regular people using this app — not just journalists and policy wonks, but regular people using it because it’s informative and fun to use,” said Hollett. “It’s easy to forget the presidential election is about regular people. We’re hoping our app changes that.”

Super Pac App’s database gets the vast majority of its videos from YouTube, as even ads designed for very specific television markets are getting uploaded online this election cycle.

“The minute an ad goes on YouTube, it gets pulled down automatically [by Super PAC App],” said Siegel.

While data about official campaign ads is relatively easy to get, SuperPACs aren’t required to report how much they spent on a particular ad. Accordingly, Siegel acknowledged that the data provided by the app may be sometimes incomplete.

“Our data can only be as good as the [Federal Elections Commission] requires organizations to share their data,” he said. “We’re plugged into the FEC firehose. When it’s streaming water, we’re getting it. But when it’s not, there’s not much we can do.”

For now, Super PAC App is iPhone-only. Siegel and Hollett are, however, considering a desktop browser plug-in for the platform.

Super PAC App is available for download in the App Store. Would you use Super PAC App to learn more about political ads you encounter on TV and on the web?

Image credit: Justin Adelson, MIT Sloan

Summary:

assistant: Super PAC app works like a Shazam for political ads, using audio recognition to identify ads, tell you who made them and do fact-checking.