Reading that article just left me with more questions :/
this post was submitted on 27 May 2025
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And here are some answers:
https://www.eurekalert.org/news-releases/982119
(a) Conventional spatial reflections: A person sees their face when they look into a mirror, or when they speak the echo comes back in the same order. (b) Time reflections: The person sees their back when they look into a mirror, and they see themselves in different colors. They hear their echoes in a reversed order, similar to a rewound tape. (c) Illustration of the experimental platform used to realize time reflections. A control signal (in green) is used to uniformly activate a set of switches distributed along a metal stripline. Upon closing/opening the switches, the electromagnetic impedance of this tailored metamaterial is abruptly decreased/increased, causing a broadband forward-propagating signal (in blue) to be partially time-reflected, (in red) with all its frequencies converted. (Adapted from Nature Physics)
So kinda like running a sound wave through a flip/reverse filter in audacity and having it switch along the “time” axis.
An upvote wasn't enough.
Thank you!
I have only skimmed the eureka alert article, but already on the surface it's so much better than... whatever the fuck that originally-linked thing is.
So thats creepy.. yep..
The researchers also demonstrated that the duration of the time-reflected signals was stretched in time due to broadband frequency conversion. As a result, if the light signals were visible to our eyes, all their colours would be abruptly transformed, such that red would become green, orange would turn to blue, and yellow would appear violet
This sounds like wave propagation through a given medium, that changes state uniformly, having an instant ‘reflection’ where the wave doesn’t bounce off of anything (so not hitting a wall… it just reverses in ‘time’) and then drops two ‘octaves’ due to energy loss.
I think the neat part isn't that - it's neat because of the time component doing it.
Yet another strange phenomenon of the quantum realm that seemed impossible but is infact real.
If I remember thinking back to my class on QED, we specifically ignored this solution because there wasn't a real world demonstration of it (which was ironic, as one of my professors was working on the problem in her doctorate).
Makes me want to find that book.
Edit: I might be wrong, I'm thinking of deriving something out of Hilbert Space to Dirac-von Neumann axioms
So basically you can see your bald spot better. I'm unimpressed.
Now that we have time crystals and time mirrors we will be able to create time lasers!
You get hit by the laser weapon before it fires!
Han never shot?
Don’t forget Time Cube!
To achieve this, the group used an engineered metamaterial designed to control electromagnetic wave behavior in unusual ways. Metamaterials allow scientists to manipulate waves far beyond ordinary mirrors or lenses.
By carefully adjusting electronic components on a strip of metal, they introduced a sudden jump that reversed the direction of incoming signals. They filled the strip with electronic switches hooked to capacitor banks.
That arrangement supplied the necessary burst of energy to force the wave to flip direction in time, an effect that used to be considered nearly impossible with accessible power.
I don't fully comprehend, but that's not a problem. Science is so effing cool.
Hey! Hey, I've seen this one! I've seen this one; this is a classic!
What you mean? It's brand new
You mean we could have read this news a dozen times already?
A dozen, a hundred, there's no way to tell.
I'm stealing this concept for my TTRPG usage!