Posted by rbanffy 4 hours ago
These are just frequencies of light, but the subjective experience of them is so much more.
And the whole thing of my perception of "red" or what I call "red" could be very different to someone else's subjective perception. But we would both call it red and associate it with the same thing, fire, love, heat, danger etc.
It's worth noting that is true of virtually everything we know. >>This is a very simple sentence.<< Anybody who understands English, 'understands' it. But what it means to understand it is perhaps completely different for each person. As long as they fit into the same place in their worldview (Lewis Caroll's Carrollian syllogisms come to mind), practically it often doesn't matter beyond recognizing the wonderful uniqueness of each human being. Likewise, unless somebody is color blind or perceives more colors than others (tetrachromats), it doesn't matter since the relationships between the different concepts or colors will be analogous amongst most people - so a common understanding within the differences is possible. Or perhaps it is more precise to say that there are so many data points in color perception or anything we know, that despite the minor differences in relationships, we understand each other because the differences must be minimal given the practically unlimited data points constraining our perceptions. In fact, when people's perceptions of things vary too much, they can be classified as mentally ill even if they understand many things perfectly well.
Like film photography doesn't happen in the lens or the world. It happens in that photosensitive chemical reaction, and the decision of the photographer.
It's an entire pipeline from photomultiplier to recording medium to the inverse process and everything is optimized not for any particular mathematical truth but for the subjective experience.
eg. Before Orange, there was only shades of yellow or reds
Similarly, you may have no idea what the name is for the color of a Tangerine, but you know what that color is. You might describe it as a dark orange. If I say the name for it is coquelicot, you can look up coquelicot and see if it matches the color you picture in your mind.
* You can pack many more different colors into fiber optic communication lines. Every color carries a few tens of GHz in modulation, but the carrier light is in hundreds of THz; there's a ton of bandwidth not used between readily available colors.
* You can likely do interesting molecular chemistry by precisely adjusting laser light to the energy levels of particular bonds / electrons.
* Maybe you can precisely target particular wavelengths / absorption bands for more efficient laser cutting and welding, if these adjustable lasers can be made high-power.
What this is actually interesting for is being able to access arbitrary atomic transitions, many of which are outside the range of conventional semiconductors (too short, usually - there's a big hole between green and red for semiconductors). That's why they talk about quantum stuff.
But I will say that precise control of laser wavelength is critical to today’s communication technologies. I doubt their new techniques will be useless.
I mean, Photonic computing already got the attention of these big tech companies.
The substance is they've created a way to fabricate a device that can make the optical frequencies they wish. That is useful: it means a designer isn't limited to frequencies that are economic to generate with existing techniques, which is a constraint that lasers currently struggle with: low cost, compact, efficient laser sources (the kind that fit on a chip, and are fabricated by cost effective processes,) only exist for a limited number of frequencies.
The story is typical tech journalism pabulum, but the underlying paper does discuss efficiency. It's about what you'd expect: 35 mW -> 6 mW @ 485 nm, for example.
An obvious use case is multimode fiber communication: perhaps this makes it possible to use more frequencies for greater bandwidth and/or make the devices cheaper/smaller/more efficient. But there are other, more exotic things one might do when some optical frequency that was previously uneconomic becomes feasible to use at scale.
Generating any wavelength. (this article)
Accurately measuring wavelength. (otherwise there's no information benefit to arbitrary wavelength generation)
Wavelength insensitive holographic gates. (If they work on that frequency, and in a way that does not change the frequency) I don't know what properties such devices currently have
Assuming all of those, your ability to compute increases to your ability to distinguish wavelengths.
You could theoretically calculate much more in a way you could never detect, but then you get into some really interesting tree falling in a forest issues.
I have an application in mind for this technology outside of photonic computing. Again, it depends entirely on price, tunability, bandwidth of the profile, etc. My understanding of the photocomputing field is limited but I never thought the major issues were wavelength related? Maybe someone can educate me.
If anyone wants to send me one of these I would be pumped.
I wish we had a large laser manufacturing ability in the West. I would say 95% of lasers of all kinds are manufactured in China.
Electrons themselves don't move at the speed of light, but information transfer (i.e. communication) via electrons does happen close to the speed of light.
A subtle, but important, distinction that's often misunderstood and means computational performance gains would probably come from bandwidth, not latency.
What should I have experienced?