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In a new paper, a group of physicists claims to have confirmed the existence of “negative time.” I had never heard of this, but I had a look at the paper. And I think I have figured it out.
Paper: https://arxiv.org/abs/2409.
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This result challenges our fundamental intuition about how time flows, but that is what makes physics beautiful. The fact that photons can exhibit negative group delay in a transparent medium has been theoretically predicted for a while, but seeing it confirmed experimentally with such precision is exciting. It reminds me of how AI image generators can now create visuals that seem to defy conventional spatial constraints. Both fields are pushing boundaries of what we thought was possible.
The idea of ´negative time´ is doubtful/wrong
Because every object on earth is transported by its rotation, is moved by the earth around the sun — and the sun-system is part of a rotating galaxy in an expanding universe
All these movements are an essential property of every object — and to stop or even reverse time does mean that all these dynamic movements have to be stopped or even reversed too.
This is not possible
Physicists have not delivered a definition for TIME up to now!
Therefore all statements about TIME are of very poor quality.
And as long we do not know what TIME is — we can not measure TIME
Bishop Augustine distinguished in CONFESSIONS (book 11, chap. 13–29) already 1600 year ago — three different types: the a) divine, b) physical, c) human time / time-perception.
When we want to understand what TIME is, then we have to discuss these three types of TIME — each seperately
Fascinating breakdown of the negative time concept. It reminds me how our perception of time shifts when we engage in deeply absorbing activities—like learning a language through interactive methods. For anyone intrigued by how time feels different in varied contexts, I found that practicing Chinese with immersive Chinese sports exercises on typingmandarin created a similar sense of time distortion, where minutes feel like seconds. Their game-based approach makes the learning process feel effortless, much like the way photons in this experiment seem to exit before entering.
This is a fascinating dive into negative time, and it really makes you appreciate how much of modern physics relies on interpreting subtle experimental signals. The idea that a photon pulse can appear to exit a medium before it enters challenges our everyday intuition, but as the author notes, it’s more about group delay than time travel. For researchers trying to visualize these kind of abstract phenomena or communicate them in papers, having the right tools is half the battle. I’ve been using Figcanvas for my own lab’s data visualization and flowchart work, and it lets you generate publication-ready scientific diagrams and data plots in minutes without needing to code. The ability to export as SVG and edit further is especially handy when you’re refining figures for a journal submission.
Fascinating discussion on negative time. As a physicist, I appreciate how experiments like these stretch our understanding of temporal order. It reminds me that many phenomena we once considered impossible are now being explored through new technologies. For example, the way AI is being used to interpret physical signs and predict outcomes is similarly expanding our boundaries. I recently came across predictive AI tools that analyze palm patterns to offer insights into personality and future possibilities, which feels like another frontier where time and prediction intersect. While it’s not quantum mechanics, it’s intriguing to see how different fields are challenging our perception of time and causality.
Fascinating article – negative group delay has been a known phenomenon in optics, but this experimental confirmation and the framing as ‘negative time’ really underscores how our intuitive notions of time can break down in quantum systems. It reminds me that staying current with such nuanced research often requires synthesizing findings across multiple disciplines. I’ve found that using AI for scientific discovery helps me track breakthroughs like this and connect them with related work, making it easier to grasp the bigger picture without getting lost in jargon. Thanks for the insightful write-up.