[negative_zero]

I think the controversy is because that while being technically correct (bar a couple of mistakes) there are two main issues:

1) To get the result presented heavily depends on the experimental setup and this appears to be hand-waved away (or for the cynics: deliberately obscured) as it would detract from the impact of the video.

2) The definition of "ON" in the video is not what anybody would reasonably define as "ON". This is not discussed in the video therefore potentially comes of as deceptive.

As an electronic engineer I actually initially found the video confusing. I wasn't familiar with Veritasium before and I will admit my initial visceral reaction was "Oh he's just one of THOSE YouTube's and needs his clicks".

It wasn't until I went back through to understand Veritasium's unspoken assumptions, simplifications and a couple of medium mistakes that I could say: yes this is technically correct.

Personally I think with some better choice of wording the pitchforks wouldn't have come out as they have.

Edit: Added word for clarity.

[notfed]

I still don't buy "then yes this is correct". If "ON" is defined as a state where ANY electromagnetic field flows into the lightbulb, then it is "ON" even before you throw the switch, because other photons are already shooting around all over the place, including from the neurons in your body pondering the result just before you throw the switch.

The definition of "ON" is exactly the main controversy with this and not a subtle detail.

[tsimionescu]

Even if we also accept the unspoken assumption that there are no other photons/electrical fields outside the experiment, the experiment is still wrong, since the battery will produce a teeny tiny electrical field even if the switch is off. This is much more visible if we assume the switch is at one end of the light-second long cables - throwing the switch has little impact on the experiment as explained.

[Ostrogodsky]

Yes but that does not generate clicks,views and that sweet youtube money.Sorry but I cannot stand those kind of guys (he, Mark Robber and the likes). Khan academy is doing something 1000000 times more valuable.

[kazinator]

"ON" is when the filament of the bulb is hot enough to emit far infra-red rays.

[BenFrantzDale]

His technical errors include the “correct” multiple-choice answer being that the time to turn on is “1/c s”. That evaluates to 3.3e-9 s^2/m. It’s not even a time. Failing basic dimensional analysis is grossly sloppy.

[Lerc]

The correct units would have tipped his hand and led people to realize the 1m separation of the wires is relevant and thus people would reconsider antenna approaches. That would blunt the gotcha effect.

That's not sloppy, it's disingenuous.

[shukantpal]

It should be obvious that the "c" here was used as a magnitude not with units. Saying that's "failing dimensional analysis" is in itself grossly sloppy - since it totally misses the context.

[SAI_Peregrinus]

1m/cs is the correct value. Not 1/cs. The meters matters, hiding it makes it less obvious that the wire separation is what matters.

[elsjaako]

If you're going tot quibble about the units, it should be "1m/c". " 1m/c s" gives a result in s².

[BenFrantzDale]

But dimensioned quantities are meaningless without units. are you saying c has a value of 1.803e+12? Or that it has a value of 1? There’s a big difference between using furlongs per fortnight and speed of light as your units for speed. By saying “1/c s” rather than “1 m/c” he was just plain wrong and certainly in no position to be smug about it.

[shukantpal]

That’s like being a grammar Nazi even when someone writes something otherwise totally clear.

And it’s obvious in this case that the magnitude of c was in metric units.

And how do you know if he was even referring to the speed of light by “c”? I could call that a dumb assumption. Because it’s obvious he was using it in a non standard way “magnitude of the speed of light in m/s”.