94 points by rbanffy 4 days ago | 9 comments
veryvisa 10 hours ago
Graphene is incredible. We've known for a while about graphene's potential but until recently the methods for producing quality graphene were too inefficient/inconsistent. Dr. Chris Sorensen at Kansas State discovered a process to create pristine graphene synthetically (vs from graphite with the scotch tape method mentioned in the article). He is currently bringing this to industry at HydroGraph Clean Power. Exciting times.
csours 8 hours ago
https://www.youtube.com/watch?v=X_crwFuPht4 AlphaPhoenix - An intuitive approach for understanding electricity
mcbishop 4 hours ago
Loosely related: This Lex Fridman discussion with a nuclear-fusion engineer, about 1-million-amp 100-million-degree electrical systems... blew my mind: https://lexfridman.com/david-kirtley
potamic 1 hour ago
Off topic, but selecting text and right clicking does not work on this site. I'm finding more and more sites of late where this is the case. Wondering if this is intentional or some issue with a popular framework everyone's using.
nextaccountic 1 hour ago
Here it works.. but, I have this installed https://addons.mozilla.org/en-US/firefox/addon/absolute-enab...
gaze 10 hours ago
2d materials are so awful to work with but keep yielding these stunningly beautiful results so physicists must persist.
stevenwoo 9 hours ago
I thought this was going to be a version of the story that appeared this week in New Scientist but it’s a different aspect of electron behavior, in the other article it talks about reducing friction in moving parts https://www.newscientist.com/article/2514425-physicists-can-...
7bit 10 hours ago
Why should we change how we teach about electricity, when we can change electricity to confirm to how we teach! :)
spaceywilly 10 hours ago
Well, the water analogy actually holds up quite well if you consider the charge field moving, not the electrons themselves. This guy has a lot of great videos using water channels to explain electricity. It is fascinating how under a high speed scope, you can see the electrical Charge “flow” like water down each branch of a circuit.

https://youtu.be/2AXv49dDQJw?si=5lPy_Mz4kJFdi80t

Brian_K_White 1 hour ago
This was the stunning one to me. Just blew my mind literally observing it run up a dead end wire and slosh and rebound like water.

Previously I was used to thinking of dead ends as simply functionally inert. That without a circuit, nothing at all happens in the dead end wire other than the potential for something to happen.

Sure I know something more than nothing actually happens since there is an elevated charge there. But still just the mental model shorthand is that no circuit = no nuthin.

But it's not. It's actually like a pipe with a little bit of air to allow for some compression, and even the dead end has a small flow that travels to the end and builds up against it, then rebounds back and eventially levels out at some homogenious but now higher pressure.

That just boggles me! I love it.

kazinator 9 hours ago
Even rubber dams stretched across pipes work exactly like capacitors. Firstly, they block DC: water cannot flow. But back and forth movement is conveyed (AC passes). Less capacitance in series, more in parallel. Two such dams in series do not have more capacitance because to get one to stretch, the other must stretch; they partially cancel. And since there are two, more pressure is needed to get the same stretch. (Same as more voltage needed to cram in the same charge: less capacitance).

Inductance doesn't have an analog. To some extent, the inertia of the fluid cam model some of it, I suppose. Like what is "water hammer" in plumbing? The circuit is too suddenly broken, but the water wants to keep moving. There's gotta be a resulting momentary pressure rise there in the closed-off line, similar to voltage rising in an interrupted inductor. If the valve were some weak piece of crap relative to the mass of the water, the water would break it: like arcing.

aeonik 6 hours ago
Inductance is like a pipe with a flywheel inside it. the water pushes through the impeller/flywheel. the flywheel resists any changes to motion.
japanuspus 55 minutes ago
Or just a long pipe where the inertia of the water resists change in motion. This is what causes the "water hammer" effect which is a problem for plumbers, but a great thing for all kinds of fun experiments, e.g. creating predictable cavitation [0].

[0]: https://www.researchgate.net/publication/321225042_A_novel_w...

westurner 3 hours ago
ScholarlyArticle: "Supersonic flow and hydraulic jump in an electronic de Laval nozzle" (2025) https://arxiv.org/abs/2509.16321 :

> The crossover from subsonic to supersonic flow coincides with a discontinuity in the local electrochemical potential, analogous to the hydraulic jump observed in supercritical classical fluids Gilmore et al. (1950). We identify the electronic shock through combined global transport and local Kelvin probe force microscopy (KPFM), confirming the presence of compressible electron flow

Additional "imaging for electron vortices" from https://news.ycombinator.com/item?id=46919958 re: the kondo effect and hydrodynamics :

> [ nanoscale scanning magnetometer, terahertz pump–probe spectroscopy ]

tug2024 10 hours ago
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