Changing the speed of light

[Ripheus23]

If the speed of light could be magically made variable, and magic could increase or decrease it, would that be at least the outline of an interesting attempt to explain how people might go "faster than light"?

[+Ark1002]

That would be cool, I like the idea.

[Caevita he/him]

The interesting thing is that the speed of light isn't really defined as being light speed. My physics teacher refers to it as the "cosmic speed limit." So, changing the speed of light might have... other repercussions. Like, gravity has to "travel" between objects at 3*10^8 m/s to take effect and pull 2 objects together. So, if this magic-enabled universe also has magic which can summon objects, and you can lower the speed limit enough, summoned matter would be weightless for a moment before gravity actually asserted itself. Which is probably way too nerdy to put in a book but hey it's interesting anyway. There's posts on nerdy websites about how if you removed all the matter which makes up the sun, the earth would keep orbiting an empty piece of space for 8 or 9 minutes. Which is just so mind-bendingly bizarre. Anyway. This has been such a tangent haha.

[Quantus he/him]

10 hours ago, Caevita said:

The interesting thing is that the speed of light isn't really defined as being light speed. My physics teacher refers to it as the "cosmic speed limit." So, changing the speed of light might have... other repercussions. Like, gravity has to "travel" between objects at 3*10^8 m/s to take effect and pull 2 objects together. So, if this magic-enabled universe also has magic which can summon objects, and you can lower the speed limit enough, summoned matter would be weightless for a moment before gravity actually asserted itself. Which is probably way too nerdy to put in a book but hey it's interesting anyway. There's posts on nerdy websites about how if you removed all the matter which makes up the sun, the earth would keep orbiting an empty piece of space for 8 or 9 minutes. Which is just so mind-bendingly bizarre. Anyway. This has been such a tangent haha.

My professors also liked to describe the Speed of Light as a Change Propagation Speed to put it in comparison to the Speed of Sound through a given medium.  Which is to say breaking it causes a violent Compression wave of whatever medium you are talking about.  Imagine for a moment a Space/Time equivalent of a Sonic Boom wave... 

Anyway, lowering that speed limit would be weird from a normal electromagnetic side of things, but I really wonder how that would interact with Cosmeric Gravity which, while also being a supposed hard Law of the Physics, seems quite subjective to the properly Invested. 

[Rossamund]

One interesting effect is that'd compress or thin out light, gravity and other stuff that travels at or near the speed of light. So when you stopped affecting the speed there'd be a segment of high or low concentration. For example if you slowed down light at night once you restored speed there'd be a big flash that'd ruin nightvision.

[Embrisk he/him]

No.
In answer to your question, the ability to change the speed of light might have some interesting consequences. It might just make time slow down or speed up, and nothing would change. However, no matter what speed the speed of light was, matter cannot travel faster.
For example, say there was a stream, and you made a little wooden boat to travel down the stream. No matter how light you made the boat, it would never travel faster than the stream unless an outside force pushed it. Whether it flowed at 3 kph, or 300 kph, there is no way the boat would could travel faster than the stream pushing it.
In other words, it would require something faster than energy, to move matter faster than energy.

Edited October 7, 2018 by Servillius

[Ripheus23]

11 hours ago, Servillius said:

In other words, it would require something faster than energy, to move matter faster than energy.

Well I realized my description was not straight FTL, so I put the phrase in scare-quotes. I guess my specific question is, would changing the speed of light allow objects to travel faster than 300,000 kilometers per second (or whatever light-speed is)?

[Embrisk he/him]

Ah, ok.