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Bowery Farming | Data Scientist, Computer Vision Engineers, Software Engineers | NYC | Full-Time | ONSITE

Bowery (https://boweryfarming.com) is the modern farming company, growing the world’s first post-organic produce. Our indoor farms create the ideal conditions for growing the purest produce imaginable. Bowery grows produce without compromise, owning the entire system from seed to store.

Software Engineering at Bowery involves developing software systems that power our modern farms. This includes building out work management, data collection, farm control, visualization, and farm automation systems. You’ll be part of idea generation, design, prototyping, planning, and the execution of new software components of all aspects of our Farms.

The engineering team is currently 4 people and we're hiring for data scientists, computer vision engineers, and software engineers. Email me at henry[@]boweryfarming.com if you're interested! I answer every email personally and would love to be introduced to any smart people you think would be interested.


Love what yall do. I wish there was a startup down here in Texas doing this. Good luck, I will be watching yall's progress!


You are spot on, the intention isn't to be spammy, its an attempt to intelligently organize video content around what people have to say about it.

Youtube (Google) incorporates plays from video embeds into its ad model, more embeds == more views == more $$ for them. They don't mind at all ;)


you should really cite your response :)


Imitation is the highest form of flattery!


+1 I'm with you on this one!



the speed of light is independent of the angular momentum... c is still c :)


This doesn't have to do with different propagation paths. The Orbital Angular Momentum (OAM) is an inherent wave property, like Wavelength or Frequency. Just like you can listen to radio on different frequencies (eg 660AM, 1010AM), you can think about this technology as "listening" on different OAM channels.

The twist in the wavefront can be thought of as a newly available subset of channels.

This has been a a field of research that has been primarily been developed in Optics, in fact, my PhD research included creating ultrafast (femtosecond), supercontinuum (white light) vortices that are capable of transmitting information over 2^L channels where L is the amount of twist the light has.


You're right that multipath is very different from SAM and OAM from a theoretical point of view. Not so much from a practical point of view though.

In current point-to-point systems you often use SAM to give you two "channels" across the link, most often referred to as horizontal and vertical polarity, but you then hook that up to the same MIMO technology that you would use for multipath.

I would expect OAM to be exploited in a similar maner for point-to-point.

The fact that SAM is very difficult to exploit for capacity in cellular applications makes me think it will be even more difficult to exploit OAM. IF you ever see it implemented my money would be on using MIMO to exploit multipath + SAM + OAM, where multipath would dominate in complex radio environments and SAM + OAM in simple more point-to-point like environments.

But that's just an educated guess of course.


Is this "twist" related to the circular polarization of light?


Quick Answer: No. Longer Answer: Sorta.

Circular polarization of light (or waves in general) corresponds to a spin angular momentum that arises as the polarization of the light is "spinning".

This "twist" is the wavefronts phase rotating or being staggered as it travels forward. Think of the wavefront of the twisted wave as looking like a piece of spiral pasta.

It is this spiraling that corresponds to orbital angular momentum.


> orbital angular momentum

Under what circumstance can you change the OAM in order to exert a torque? (or maybe vice-versa: What is an example of torque exerting a change in OAM on the wave?)

TIA.


If I understand your question..

You can prepare waves in such a way that forces them into this spiraled waveform state. This can be done in a cavity (in the case of lasers) as there are solutions of the wave equation that give rise to OAM; or this can be done by using diffractive optics, like a hologram, that somewhat force the wave into this state. It is this case that you can think of a torque being exerted onto the waves.

Waves too, can exert torque on small particles (micron sized polystyrene spheres for instance). Light with spin or orbital angular momentum can be used to make these small object rotate!


> Light with spin or orbital angular momentum can be used to make these small object rotate!

Thank you, that was exactly the effect I was looking for. Any links handy? Fascinating stuff, this from an old microwave-digital guy.


Sure! Here's a research group in Glasgow that has a great site: http://www.physics.gla.ac.uk/Optics/play/photonOAM/

And here is the lab where I did my undergrad research (Colgate Univ.): http://departments.colgate.edu/physics/research/optics/oamgp...

happy to offer up my phd thesis as well: http://shel.tv/henry_thesis


If you ever find yourself in Santa Monica, the beer is on me.


Does launching a wave with OAM require an antenna with spatial extent, or can it be done by a point source?


This reminds me of my physics days at the City College of NY! Awesome puzzle and a cool way to learn about cellular automata...


I like that point. Googling your name shows interesting things about who you are. Getting "above the fold" is surly important!


The most interesting thing a google search for my name reveals is that I have a very common name.


The whole point of being a "startup" is to find a business strategy and not be a startup! I agree with this post and think more startups should point out HOW they "could be a platform" rather than focussing on how they are one, which they most likely are not (which as the point of this post, i think, and the original citing article that got so much buzz yesterday)


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