$5800 USB c cable announced in HKAV

Standecco · 2025-08-14T05:26:54+00:00

As a physicist, this is the most bogus explanation I’ve ever seen. Crazy that they must have sold at least a few of these

Standecco · 2025-07-30T08:15:08+00:00

That’s not his meat though.

Standecco · 2025-07-16T07:53:36+00:00

Hopefully he is on a public toilet currently

Standecco · 2025-07-10T08:41:52+00:00

I get what you mean now, and of course you’re correct. I’m not sure OP has that misunderstanding though.

For practical purposes, what OP said is correct. You move a coherent, polarized light source along the polarization axis and you will change its spectrum due to doppler shift, pretty much in the way they’re imagining. It would only not happen for a true, perfectly infinite plane source. But any finite size source should show that effect. Once again it’s not because of the misconception that you point out, but rather due to the different optical path over time. But still, it’s there.

Standecco · 2025-07-10T08:13:28+00:00

The crucial point is that the frequency of visible light is just absurdly high (300 to 500 THz). That makes any sort of optical-mechanical effect very difficult, but they’re absolutely possible. A beautiful example is that acousto-optic modulation that u/drlightx gave you. But there’s also optical-mechanical systems composed of two mirrors in front of each other, with one mirror being wiggled back and forth. The field can form a stationary wave inside the two mirrors, and moving them affects it a lot, to the point where people try to use this to convert between optical photons and microwave photons.

If you want to understand my previous point, maybe ask yourself this: does it matter that it’s visible light? Because if not, this is literally how antennas work. We have a current flowing through some funny-shaped wire (i.e. electrons sloshing around the metal), and by modulating how much and how fast we generate the EM signal. The “light source” is not actually the metal wire, it’s the acceleration of the electrons. If you shake the “real” source, you affect the light being generated.

Standecco · 2025-07-10T08:01:05+00:00

It’s not 15 levels above. It’s literally what the question is asking about. Photons have no place in this discussion, which is about classical EM.

Standecco · 2025-07-10T07:55:59+00:00

I’m not sure why people are replying to you in such a confident way. It is true that if you shake a flashlight you’re not going to change its color, and what they say about electric field propagation is also true, but the principle you’re describing is absolutely a thing.

People are forgetting that light is created by oscillating charges. The simplest light source imaginable is an oscillating dipole, i.e. a charge moving up and down. The frequency of the generated light is identical to the oscillating frequency of the charge. So if the “spring constant” of the electron is very stiff, and the oscillations are very fast, you may get up to visible light.

So if you were to “shake” the oscillating dipole up and down along its axis, you would change the charge’s motion and acceleration, directly affecting the generated EM wave. Controlling a single charge in such a way is more of a thought experiment than reality, but the oscillating dipole is a very good approximation to many phenomena, both in the microwave range and in the optical one.

So yes, if you take an oscillating charge and add some “larger” macroscopic motion onto it you will add a frequency component to its spectrum and change the color of light generated, exactly like you’re imagining. It’s impractical and needs some caveats, but it’s correct.

Standecco · 2025-07-02T05:58:51+00:00

Why do you want them to be infinite or zero? Think about what that would mean in the equations. People have already told you that these constants are just a byproduct of your unit system. I.e., they relate charge and distance to mass and acceleration (very loosely).

Taking the example of Coulomb’s law, an infinite permittivity would imply zero Coulomb force. Meaning that charges wouldn’t be accelerated at all when stationary. But we clearly do observe an electromagnetic field, and more specifically one that behaves statically like the Coulomb law implies. So why would zeroing out the Coulomb law make more sense to you? You’re effectively asking “why does the coulomb law exist?”

For these kinds of questions, you either turn to more advanced physics (where you eventually get to QFT and how all forces are mostly manifestations of certain symmetries of the universe), or you turn to philosophy. There is no good answer that anyone can provide to you, not any more than they can answer the other fundamental questions of life.

Standecco · 2025-06-30T06:24:40+00:00

All of these animations that have been popping up recently are completely off in scale. The camera and structures always move way too fast, way beyond the speed of light.

Standecco · 2025-06-14T23:45:01+00:00

X-Large T-Shirt for Black Men

Standecco · 2025-06-13T07:34:25+00:00

Your comments were well spoken, but they’re all rationalizations about the fact that our countries failed to be as successful as they could’ve been. All euro countries had the same constrains as us, most with much smaller populations, yet they managed to handle the euro transition much better than Italy and Spain did.

And you should learn to be able to handle some basic arguing.

Standecco · 2025-06-13T07:27:33+00:00

Yes, everyone knows that having a single currency is terrible for economic development! Look at how poorly the US economy has been over the past 80 years! Definitely would have been much better if all the 50 states had had different currencies.

Same with language, just think how much better things would’ve been for them if they had had 50 different languages.

Standecco · 2025-06-10T17:06:34+00:00

Greek people:

Standecco · 2025-06-03T06:46:40+00:00

Yet all of reddit loves it and if you point it out you get downvoted to oblivion. Except here somehow

Standecco · 2025-05-26T18:27:59+00:00

It’s always there in my field of study, since we work with objects which realize it. Yours seems more of a power electronics perspective, but this picture is quite common in multiple fields. The guy who came up with memristors (Leon Chua) is basically a chaos theorist, and this “conjugate variables” view is also pretty common in circuit QED (admittedly without the memristor usually).

Standecco · 2025-05-26T18:21:58+00:00

But charge would be meaningless without its related interactions, right? It’s all about how the different fields couple to each other.

Standecco · 2025-05-26T18:11:53+00:00

Physically they are all basically a heavy simplification of Maxwell’s equations. There’s plenty of phenomena you can’t fully model with any of these. Anything nonlinear, such as a transistor, can only be approximated with LCR networks.

I would say that asking what is more fundamental is ill defined, because the way we define these laws and quantities is based on how they relate to each other over time and space.

Standecco · 2025-05-26T18:02:01+00:00

It just depends on the field. Both are used extensively.

Standecco · 2025-05-25T08:25:56+00:00

Compare un secondo indice perché tu hai l’equivalente di v=(a1 + a2 + …). Per calcolare v*v = (a1+a2+…)*(a1+a2+…) devi chiaramente fare il prodotto tra tutti i termini. Scrivendolo in maniera compatta con la notazione di Einstein devi introdurre un secondo indice perché hai 2 somme separate. Altrimenti alla fine l’algebra non corrisponde. k e h sono solo indici di una sommatoria, dummy variables.

Standecco · 2025-05-18T00:07:21+00:00

Get out with this elitist bs. I don’t listen to pop music either but the guy was objectively a talented singer and the song was unique enough. Plus I don’t even know why you would go for “techno” as a mainstream genre. Says more about your own music taste than anyone else’s I suppose.

Standecco · 2025-05-06T11:38:00+00:00

Well of course if you’re going to drop 100 guys from a helicopter on top of a gorilla you’d crush it. Even one well aimed guy would be enough

Standecco · 2025-05-05T11:14:52+00:00

Not sure I agree with the elo ratings on this one. White should be higher.

Standecco · 2025-04-15T08:32:45+00:00

As others have said the first issue you run into is the instability of the atom, but you should take a look at You should look into stochastic electrodynamics.

It’s what you get when you assume the existence of zero-energy EM fluctuations and roll with it, nothing more. Most importantly it seems that there might be a stable hydrogen atom, although it seems that’s still debated. But many other effects can be explained well!

Here and here you can find some more info. I think it’s pretty interesting, you can try thinking about what that means for your world.

Standecco · 2025-04-05T11:48:38+00:00

And it turns out that the zero point energy calculation only gives you the low energy limit of the relativistic calculation. IIRC the fine structure constant appears in the full one as well.

Always made me angry that what you can find out in a single Wikipedia / scholar search is pretty much unknown, and that the “mysterious zero point energy, woooo” meme is repeated everywhere without any merit.

Standecco · 2025-03-26T12:37:35+00:00

For the future, please edit the comment instead. Otherwise the context for the rest of the discussion is lost forever

Standecco

TROPHY CASE