Australian Physicists Build Reversible Tractor Beam 71
An anonymous reader writes: Physicists at Australian National University have developed a tiny tractor beam that improves in several ways upon previous attempts. First, it operates on scales which, while still tiny, are higher than in earlier experiments. The beam can move particles up to 200 microns in diameter, and it can do so over a distance of 20 cm. "Unlike previous techniques, which used photon momentum to impart motion, the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them (abstract). The ANU team demonstrated the effect on gold-coated hollow glass particles. The particles are trapped in the dark center of the beam. Energy from the laser hits the particle and travels across its surface, where it is absorbed creating hotspots on the surface. Air particles colliding with the hotspots heat up and shoot away from the surface, which causes the particle to recoil, in the opposite direction. To manipulate the particle, the team move the position of the hotspot by carefully controlling the polarization of the laser beam."
Still a long way to go ... (Score:5, Funny)
Re:Still a long way to go ... (Score:5, Informative)
Eh, the original Enterprise NX01 did pretty well for itself just using a good old fashion grappling hook. Plus slamming your foe with a grappling hook makes for bad-ass space fights.
Re: (Score:2)
But which is better from 100 000 km away in poor lighting?
Re: (Score:2)
Re: (Score:2)
Now get it to the right place.
Re: (Score:1)
...always seemed like a ridiculous method to deliver a flashlight to someone you don't like.
Tractor (Score:2)
Considering the Beam is limited to 20cm right now, my money is on grappling hooks...
Then again, if looking for space battle damage, firing an actual Tractor at the target might be more effective.
Re: (Score:1)
Re: (Score:1)
" the Borg makes viruses look like sheer child's play."
Um, you realize Star Trek is FICTION, right?
Re: (Score:3)
Whooosh ?
Re: (Score:2)
" the Borg makes viruses look like sheer child's play."
Um, you realize Star Trek is FICTION, right?
In space,no one can hear you whoosh.
Re: (Score:2)
I was going to say "mount the controls above a yawning chasm inside an artificial moon, yet within walking distance of the hangar bay". Yours works too though.
G'day mate!!!!!!!!! (Score:1)
Re:G'day mate!!!!!!!!! (Score:4, Insightful)
All the better to keep the ugly sheelas away with eh? Chuck another shrimp on the barbee skip!!!
Bugger me, another flaming mongrel is trying to speak 'strayan but using shrimp instead of prawn...
Get the tractor beam warmed up Bazza. I'll move the Camira so we can get to the Torana so we can get the Commo out of the shed. I'm pissed as buggery now.
Re: (Score:2)
Almost a microwave (Score:5, Funny)
...the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them.
Oh, boy. It cooks you as it moves you.
Sounds like a great formula for a space rotisserie.
Re:Almost a microwave (Score:4, Insightful)
Re: (Score:2)
While you evaporate, there's a moment when you're surrounded by your own gas molecules, which can be used to push you forward, I suppose.
So... useless in space then.... (Score:3, Insightful)
"Unlike previous techniques, which used photon momentum to impart motion, the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them
Need I say more?
Re: (Score:1)
20cm range, heats while travelling. A dream for the instant food eating couchpotato.
Might be useless in space, but we have a whole planet full of people where it might still be usefull (or become so with more development). spacenutters are so narrowminded.
Pusher beam, not reversible tractor beam (Score:4, Informative)
Lets learn to speak the language, shall we?
Tractor's pull. A tractor beam would pull. This pushes. It can't pull. This means its not a reversible tractor beam, which would mean it can pull and be reversed to push ... it can only push.
Its a pusher beam, and it only works in a fluid, on objects with tiny amounts of mass that can stand to be roasted into oblivion in order to move them less than distance of a reasonable sized dictionary.
Re: (Score:2)
Re: (Score:2)
The semantics are still screwed up as the laser does no pushing or pulling itself but simply heats up the little, tiny gold sphere. It's pretty tenuous to say that the machine generating the light being converted to surface temperature heating the air which bounces off the surface is providing traction.
Re: (Score:2)
Lets learn to speak the language, shall we?
Tractor's pull. A tractor beam would pull. This pushes. It can't pull. This means its not a reversible tractor beam, which would mean it can pull and be reversed to push ... it can only push.
Its a pusher beam, and it only works in a fluid, on objects with tiny amounts of mass that can stand to be roasted into oblivion in order to move them less than distance of a reasonable sized dictionary.
Did you read more than the headline?
Actually, never mind. Stupid question.
Re: (Score:3)
Lets learn to speak the language, shall we?
OK...
Tractor's pull.
That apostrophe shouldn't be there.
Re: (Score:2)
So then it's a Retractor-beam.
Re: (Score:2)
(I've usually seen the 1st spelling, though the second is used sometimes.)
Re: (Score:2)
Hmmm I don't understand why the distinction matters or why "tractor beam" needs to mean something so specific. At a very high level the overall effect is "I turn on the beam, and this object is moved towards me"
As long as the manipulated object is manipulated by the beam and is passive in its interaction (that is it is not appreciably changed and contributes no energy of its own that was not imparted by the beam), then "tractor beam" seems just fine to me.
whether it is some sort of attractive force or sligh
Australian Physicists Build Reversible Tractor Bea (Score:2)
Australian Physicists Build Reversible Tractor Beam
No they didn't. Not even remotely.
the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them
Re: (Score:1)
Australian Physicists Build Reversible Tractor Beam
No they didn't. Not even remotely.
the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them
Exactly. If I built a system that deployed a wheeled robot controlled by RF signals to drive over to something and push it toward me, that would be as much of a "tractor beam" as this is.
Re: (Score:2)
Australian Physicists Build Reversible Tractor Beam
No they didn't. Not even remotely.
the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them
Exactly. If I built a system that deployed a wheeled robot controlled by RF signals to drive over to something and push it toward me, that would be as much of a "tractor beam" as this is.
If you did it without the robot and only used the rf beam in some way sure. This may not be a true tractor beam but at least it is a beam and it does tract. So your remote controlled fetchbot is just that. Did they say in Star Trek "use the tractor beam" to which some red shirt gets in a shuttle to get whatever they wanted?
Reverse the polarity of the emitters! (Score:2)
To manipulate the particle, the team move the position of the hotspot by carefully controlling the polarization of the laser beam."
And you all thought that the Star Trek writers were just spouting nonsense...
Re: (Score:2)
In fairness, they were ... and they knew it.
Throw out enough techno-babble, and sooner or later you might be right just by accident. :-P
"Reversible Tractor Beam"? (Score:2)
It's called a Repulsor Beam, you nimwits.
Re: (Score:2)
At least it's better than my raincoat!
Does this mean... (Score:1)
We'll have a Moore's Law type thing for tractor beams soon? :)