| HN Mirror

https://thedebrief.org/impossible-photonic-breakthrough-scie... :

> For decades, that [Abbe diffraction] limit has operated as a sort of roadblock to engineering materials, drugs, or other objects at scales smaller than the wavelength of light manipulating them. But now, the researchers from Southampton, together with scientists from the universities of Dortmund and Regensburg in Germany, have successfully demonstrated that a beam of light can not only be confined to a spot that is 50 times smaller than its own wavelength but also “in a first of its kind” the spot can be moved by minuscule amounts at the point where the light is confined.

> According to that research, the key to confining light below the previous impermeable Abbe diffraction limit was accomplished by “storing a part of the electromagnetic energy in the kinetic energy of electric charges.” This clever adaptation, the researchers wrote, “opened the door to a number of groundbreaking real-world applications, which has contributed to the great success of the field of nanophotonics.”

> “Looking to the future, in principle, it could lead to the manipulation of micro and nanometre-sized objects, including biological particles,” De Liberato says, “or perhaps the sizeable enhancement of the sensitivity resolution of microscopic sensors.”

"Electrons turn piece of wire into laser-like light source" (2022) https://news.ycombinator.com/item?id=33493885

Could such inexpensive coherent laser light sources reduce medical and neuroimaging costs?

"A simple technique to overcome self-focusing, filamentation, supercontinuum generation, aberrations, depth dependence and waveguide interface roughness using fs laser processing" https://scholar.google.com/scholar?start=10&hl=en&as_sdt=5,4... :

> Several detrimental effects limit the use of ultrafast lasers in multi-photon processing and the direct manufacture of integrated photonics devices, not least, dispersion, aberrations, depth dependence, undesirable ablation at a surface, limited depth of writing, nonlinear optical effects such as supercontinuum generation and filamentation due to Kerr self-focusing. We show that all these effects can be significantly reduced if not eliminated using two coherent, ultrafast laser-beams through a single lens - which we call the Dual-Beam technique. Simulations and experimental measurements at the focus are used to understand how the Dual-Beam technique can mitigate these problems. The high peak laser intensity is only formed at the aberration-free tightly localised focal spot, simultaneously, suppressing unwanted nonlinear side effects for any intensity or processing depth. Therefore, we believe this simple and innovative technique makes the fs laser capable of much more at even higher intensities than previously possible, allowing applications in multi-photon processing, bio-medical imaging, laser surgery of cells, tissue and in ophthalmology, along with laser writing of waveguides.

TL Transfer Learning might be useful for training a model to predict e.g. [portable] low-field MRI with NIRS Infrared and/or Ultrasound? FWIU, "Mind2Mind" is one way to ~train a GAN from another already-trained GAN?

From https://twitter.com/westurner/status/1609498590367420416 :

> Idea: Do sensor fusion with all available sensors timecoded with landmarks, and then predict the expensive MRI/CT from low cost sensors

> Are there implied molecular structures that can be inferred from low-cost {NIRS, Light field, [...]} sensor data?

> Task: Learn a function f() such that f(lowcost_sensor_data) -> expensive_sensor_data

FWIU OpenWater has moved to NIRS+Ultrasound for ~ live in surgery MRI-level imaging and now treatment?

FWIU certain Infrared light wavelengths cause neuronal growth; and Blue and Green inhibit neuronal growth.

What are the comparative advantage and disadvantages of these competing medical imaging and neuroimaging capabilities?