The Speed of Light is NOT About Light

There's an episode of PBS Space Time about this, "The Speed of Light is NOT About Light" [1], which comes pretty close to making the same points you are making. It might be useful to watch this earlier episode, "Are Space and Time an Illusion?" [2], first. There is a later episode (or maybe a couple of them) that go into how interactions with the Higgs field make it so things with mass travel slowed than the speed of causality. To tie back to the warp drive news, they have an episode that would be a good place to start on warp drives, "Is The Alcubierre Warp Drive Possible?" [3]. There's also "Superluminal Time Travel + Time Warp Challenge Answer" [4], and "Will Wormholes Allow Fast Interstellar Travel?" [5]. A non-warp unknown physics drive that comes up a lot also got an episode, "The EM Drive: Fact or Fantasy?" [6]. There is at least one episode covering interstellar travel without using any unknown physics, "5 REAL Possibilities for Interstellar Travel" [7]. The scope of the series is basically anything vaguely connected to astronomy, cosmology, and quantum mechanics, and the episodes are all pretty short (5-12 minutes), so it is a great thing to watch when you've got a short wait for something. Here's the series home page [8], and their YouTube channel [9]. Also on the PBS streaming app, for those who like to get their physics on their big screen TVs. [1] ▶ this video [2] link [3] link [4] link [5] link [6] link [7] link [8] link [9] link

PBS SpaceTime has a treatise on relativity. There are a dozen videos worth watching on this topic alone. The video about “the speed of causality” is the one that caused me to level up: ▶ this video Here is a 12 video playlist on relativity: link Here is a six video series on measuring space and time: link

As an aside, the PBS space time video The Speed of Light is NOT About Light : ▶ this video As an aside to the aside - as I rewatch it I quickly notice how young he looks (and then note the date is 2015 on there - one of the early ones and the production is less refined). You may also like The Geometry of Causality link

You’re correct. The speed of light is not actually about light. ▶ this video has a great explanation from the always excellent PBS Space Time, for the curious.

Some of the confusion is, I think from referring to speed of light as "speed of light". When it really is speed limit of causality between 2 points in space. And light (em waves) just happen to be able to hit that limit. Now since expansion of space is itself not going to allow one point in space to cause any effect on another, it (the expansion) can be faster than speed of causality. PBS space time has a good video on this - ▶ this video

Posted this to a point above, but probably more pertinent here, so reposting - Some of the confusion is, I think from referring to speed of light as "speed of light". When it really is speed limit of causality between 2 points in space. And light (em waves) just happen to be able to hit that limit. Now since expansion of space is itself not going to allow one point in space to cause any effect on another, it (the expansion) can be faster than speed of causality. PBS space time has a good video on this - ▶ this video

@mesid asked in a now dead comment: > What does speed of causality mean? And how is light so close to that? Take a look at this video by PBS Space Time on the topic: ▶ this video You may need to go down the rabbit hole and watch the earlier videos on relativity and related topics.

Speed of light is not really just speed of light, but universal speed limit of causality. Light (electromagnetic waves just happens to be one of the few things capable of hitting that limit. Even the effect of gravity is limited to speed of light. PBS Space time has a good video on this - ▶ this video . So to answer your question, no it is not possible for anything to affect us any faster than the universal speed limit of causality (that light happens to be able to hit).

Something to head off likely confusion: The Speed of Light is not about the Speed of Light. ▶ this video Don't get these two things mixed up: - The speed of electromagnetic waves in the local medium - The maximum speed our reality allows for causal phenomena

These PBS Spacetime episodes should help: The Speed of Light is NOT About Light - ▶ this video Is Quantum Tunneling Faster than Light? - link The Quantum Experiment that Broke Reality - link Pilot Wave Theory and Quantum Realism - link The Future of Gravitational Waves - link

I don't understand why the video needs be so negative. Why dump on other videos? And unfairly so! > Science educators love to make videos about relativity, but surprisingly few of them seem to understand what this stuff really means. The two examples the video gives of science educators that don't "know what this stuff means" are Don Lincoln and Matt O'Dowd. Both have PhDs in physics. Lincoln was on the team that discovered the Higgs boson. O'Dowd is a professor at CUNY. They know what they're talking about. Then the video gives as an example of a bad explanation the PBS Space Time on the speed of light. But that video makes pretty much the same argument. That the speed of light/causality falls out logically even if you don't postulate it. The author clearly didn't watch that video carefully ▶ this video I would have subscribed to this channel, but this tone is a bad look.

"c" isn't "the speed of light" so much as "the speed of causality". Light just happens to be massless packets of energy that move at the speed of causality. For all intents and purposes this is happening in real time from our local frame of reference. ▶ this video