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Tractor Beam Created Using Water Waves
KentuckyFC writes The idea that light waves can push a physical object is far from new. But a much more recent idea is that a laser beam can also pull objects like a tractor beam. Now a team of Australian physicists has used a similar idea to create a tractor beam with water waves that pulls floating objects rather than pushes them. Their technique is to use an elongated block vibrating on the surface of water to create a train of regular plane waves. When the amplitude of these waves is small, they gradually push the surface of the water along, creating a flow that pushes floating objects with it. However, when the amplitude increases, the waves become non-linear and begin to interact with each other in a complex way. This sets up a flow of water on the surface in the opposite direction to the movement of the waves. The result is that floating objects--ping pong balls in the experiment--are pulled towards the vibrating block, like a tractor beam.
I doubt those were the same experiment, even to each other...
Do not look into laser with remaining eye.
Large scale: cleaning up oil spills.
Small scale: Device for more effectively scooping up dirt and dropped leaves from a swimming pool.
If you can compress space to achieve warp speed, you can then also compress space to create waves in the vacuum.
This is a pretty awesome result if it didn't depend on coincidence.
That's why I don't use penicillin.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Yeah, with a video, you have a reliable proof for every theory.
It's like putting too much air into a balloon!
#DeleteChrome
If only we had some sort of robot that could bend things for us
rewriting history since 2109
Gravity bends space, although always in the same basic way. (I think)
So lets imagine there may be some other way of bending space...
What?!?! Next you are going to tell me that gravity can somehow draw one object towards another. Preposterous!
Tell this to all the gardeners and landscaping crews in the country, as instead of raking up leaves now, their favorite toy seems to be the leaf blower to scatter all the debris to neighboring yards so they can get paid to do it there next.
FWIW, this paper talks about doing this with light (in the context of micro-manipulation). Doesn't look like we will be using this for any star-ship sized objects in the near future...
The basic idea is that you use a light with a specific profile to stimulate the object you want to attract in a way that causes a scattering field such that there is a net force backward to the emitter (it only works if the amount of net forward momentum of the light is relatively small compared to the scattering).
The water stuff referenced by this article works on a completely different principle, though as described here.
They are similar in that they originate with a wave generator, also hitting the target at a glancing angle is a way to achieve the necessary conditions and both provide a net attractive force (aka tractor beam), but the physics is totally different.