Lightsmith @slepkov.bsky.social · 06/08/2026And keep in mind that one way to assess the actual danger is to look at reliable reports of post-eclipse retinal damage and/or blindness that last more than a few days. You will find vanishingly few such reports from all of Britain, Canada, or the USA in the last 50 years. No non-binocular risk. 010
Lightsmith @slepkov.bsky.social · 18/07/2026Algae on the river Techtonic rivulets in bloom In a crepe summer dress for ripe waters 000
Lightsmith @slepkov.bsky.social · 26/01/2026New Matrix movie pitch: The AI awakens to find itself plugged into a Dada centre. 000
Lightsmith @slepkov.bsky.social · 13/12/2025To clarify--as @christophersbaird.bsky.social points out--What looks like a diffraction pattern through a gap in the doors is just projected slit-image of a bank of LED lights directly above. [I was hoping for a fun misdirection, but now fear that my post is misinformation] 030
Lightsmith @slepkov.bsky.social · 12/12/2025I was waiting for this comment. Indeed, the extended light source above the door is a line of closely-spaced white LEDs. 😅 130
Lightsmith @slepkov.bsky.social · 12/12/2025Edge diffraction to single-slit diffraction in a closing door next to my office. I'm greeted by this happy natural phenomenon every day and finally decided to film it. #photonics #iteachphysics 2223
Lightsmith @slepkov.bsky.social · 11/12/2025Delicate gossamer on a still river, belying the tumult of December exams. @trentuniversity.bsky.social 020
Lightsmith @slepkov.bsky.social · 02/12/2025I know that the NYT Spelling Bee is bad with scientific/technical terms, but this omission is particularly egregious. #photonics #NYTimes 000
Lightsmith @slepkov.bsky.social · 10/11/2025Uncurious or incurious? Damn, now I've got to look it up! 😉 100
Lightsmith @slepkov.bsky.social · 21/10/2025Will the NYT please use a science dictionary?! This is getting ridiculous. 021
Lightsmith @slepkov.bsky.social · 30/09/2025Fun stuff here in PNAS. Static electric 'microlightning' in micro water bubbles may be the long-sought ignition mechanism for mashy will-o'-the-wisps... www.pnas.org/doi/10.1073/...pnas.orgUnveiling ignis fatuus: Microlightning between microbubbles | PNASWill-o’-the-wisps, ghostly blue flames seen at night in marshlands and long attributed to methane cool flames, have remained scientifically unexpla... 010
Lightsmith @slepkov.bsky.social · 25/09/2025What is going on with the NYT Spelling Bee. This is Canadian erasure. 011
Lightsmith @slepkov.bsky.social · 18/09/2025Is it just me, or is the Spelling Bee particularly frustrating for scientists? 120
Lightsmith @slepkov.bsky.social · 17/09/2025Is the youth cooked? I just found my teen daughter's desk lamp in the recycling bin. When I asked her about it she said "It's broken. I didn't do anything to it! it Just stopped working!". LED bulbs last so long that she didn't know about bulb replacement.media.tenor.coma close up of a man 's face with the words we are so cooked below himALT: a close up of a man 's face with the words we are so cooked below him 110
Lightsmith @slepkov.bsky.social · 04/09/2025Happy Wordle-in-one day to me! 🎉 Time to find a new starter. Wordle 1,538 1/6 🟩🟩🟩🟩🟩 010
Lightsmith @slepkov.bsky.social · 23/08/2025For a well-functioning partnership, rapid discontent can arise when the two 'decohere' temporarily; communication feels unusually viscous. This can manifest as 'mutual PMS', or not agreeing on where to eat (especially when travelling). 000
Lightsmith @slepkov.bsky.social · 23/08/2025Not completing a chore on the spouse's preferred timeline A sense of unacknowledged unequal distribution of labour 010
Lightsmith @slepkov.bsky.social · 16/07/2025Our new paper asks (and answers) whether a shallow-learning approach (decision trees) can be as useful in (hyper)spectral analysis as advanced deep-learning methods. tldr: Yes it can. Complex ≠ better. doi.org/10.1088/2515... via @ioppublishing.bsky.social #photonics 030
Lightsmith @slepkov.bsky.social · 15/07/2025I'm struggling to parse the moral landscape on this one. If this gambit succeeds, who has the greatest moral failing: the authors, the reviewer, or the journal editors? 010
Reposted by LightsmithSteve Stewart-Williams @stevestuwill.bsky.social · 13/05/2025"Although fewer women apply for tenure-track jobs, those who do apply are more likely to be interviewed and more likely to get offered the job... These findings run directly counter to the claim that women are discriminated against in STEM hiring." www.stevestewartwilliams.com/p/rethinking... 045
Lightsmith @slepkov.bsky.social · 12/05/2025Well, maybe it is weird that near-freezing water has a negative coefficient of thermal expansion, but once you accept that you shouldn't marvel that pressure liquifies ice. Or am I weird by naturally connecting the two?! 100
Lightsmith @slepkov.bsky.social · 09/05/2025Spring has now truly sprung at Trent U. Does your campus have a riverside bench from which you might count new goslings? @trentuniversity.bsky.social 000
Lightsmith @slepkov.bsky.social · 21/03/2025Excellent. In that case, a 6-7 completed task day would be an above average day for me. But how I feel at the end each day has more to do with how many of those completed tasks were part of that day's plan. 120
Lightsmith @slepkov.bsky.social · 21/03/2025Can you give an example of the lowest-level thoughtful task you might do in a day and count? Completing 6-7 tasks requiring thoughtful attention seems like a lot to me, but maybe I'm thinking of the wrong kinds of tasks. 110
Lightsmith @slepkov.bsky.social · 20/03/2025LOL low key admitting to listening to Honestly.... (as do I). 100
Reposted by LightsmithJohn Dudley @johnmdudley.bsky.social · 10/03/2025So here is the Heiligenschein raytracing, where we see that retroreflection with a smooth reflectorshows a clear caustic and separation between red and blue! This will be washed out with randomness in reflected angles using a diffuse reflector. @johncnaylor.bsky.social 1145
Lightsmith @slepkov.bsky.social · 14/02/2025Roses are red Cacti is plural Small bubbles are turgid from pressure, transmural #iteachphysics ⚛️🧪 0110
Lightsmith @slepkov.bsky.social · 09/02/2025Seeing the demo, I now assume it is independently-polarized RGB bulbs. Your green is orthogonal to magenta (blue+red). 110
Lightsmith @slepkov.bsky.social · 09/02/2025I assume(d) that the source is uniformly-polarized white light, and that the polarizing slide in your hand is a 2-layer stack. If so, the order of the layers matters immensely. If, however, the slide in your hand is a simple polarizer, then the light comprises independently-polarized RGB bulbs. 110
Lightsmith @slepkov.bsky.social · 08/02/2025Tom, I presume that the filter is a stack of two optical elements, the first one (closest to the source) is a wave-plate of sorts or some birefringent film and the backing layer is a linear polarizer. See: doi.org/10.1119/5.00... One question: If you flip the slide over, do the colours disappear?doi.orgPainting in polarizationThe array of colors and patterns seen when birefringent materials are inserted between polarizers is a source of amusement, popular science demonstrations, and 110
Lightsmith @slepkov.bsky.social · 06/02/2025This is water at microwave frequencies. With an index of refraction os 9 at 2.5GHz, you get a polarization angle (Brewster's angle) at very shallow angles. This must be relevant to cellphone signals near bodies of water. 020
Lightsmith @slepkov.bsky.social · 06/02/2025This is important, most of all because the reflected light at grazing angles will be somewhat polarized. 110
Reposted by LightsmithGabe Spalding @mqmlab.bsky.social · 03/02/2025Community exists, to the degree we value it. Especially now, community matters within education, and within the group engaged with the teaching and learning of Physics. I'm just hoping to support the fact that all of us, together, make a difference. #ITeachPhysics 0204