# Effects of Relativistic/Inertial Mass

What would happen to a ball of ice in a remote region of space if spun in a circle accelerating toward the speed of light?

As the ball of ice approaches the speed of light, does it melt/sublimate as inertial/relativistic mass increases? Will the water molecules eventually break apart into Oxygen and Hydrogen? Will the atoms eventually break into photons?

• I've never been formally educated in Physics, so please forgive my ignorance. I've recently become interested after a few years self-studying philosophy brought me to a lecture on the implications of modern science on redefining our reality. – Jacob Barnes Jun 10 at 20:31
• Do you mean the ball spinning around its axis? Or a ball moving in a circular orbit like a planet around the Sun? – nasu Jun 10 at 21:12
• I guess either but I was imagining the latter. – Jacob Barnes Jun 10 at 21:50
• Follow-up question: would it matter which? At least in respect to my question wouldn't it basically be the same thing? – Jacob Barnes Jun 10 at 21:52
• I think you are asking about what happens to a ball of ice as it approaches light speed in an idealized scenario, no wind resistance or other friction, no gravitational gradient effects, no rocket engines or other sources of unequal forces on different parts of the ice ball, etc. the answer is nothing. Motion is relative. If the ice ball is free from forces, you can easily change coordinates to find a frame where it is not moving. – 511mev Jun 11 at 0:06

It matters to understand the question before you can think about the answer. That's why I asked you to specify the situation.

From your answers to the other comments It seems that you think that the speed of the ball has some influence on its internal energy, resulting in the ball evaporating and so on. This is not the case, as it was already mentioned. However none of your scenarios are good illustrations for this scenario.

A spinning ball, made from real materials will break into pieces at speeds way below the speed of light. This has nothing to do with relativity. It's just that the bounds between the atoms or molecules of the solid can sustain only that much centripetal force and as the spinning speed increases more centripetal force is required.

For the orbital motion of the ball, a similar problem will arise. If the ball moves faster either you need a larger trajectory or an increased centripetal force. In order to have circular motion you need some attractive force, like gravity. So in a very remote area of the universe, in absence of other bodies, what will make your ball go in a circular trajectory, anyway?

You see, if you want to discuss the effect of relativistic speeds alone, on an isolated body (in a remote area), you should choose a situation where the body moves in straight line, to eliminate the need for forces. This is the only type of motion for an isolated body. And in this case, there will be no reason for the body to change the state in any way.

• Ok, I guess I asked a bad question. The reason I specified the circle pattern, like someone swinging a rope with a weight on the end, is because it wouldn't eventually interact with anything else. The reason I thought relativity was involved was because the increase in inertial mass results in increased energy, which I thought would change the state of the matter. So, in my question, nothing in particular was causing the circle motion, it was more of a thought experiment. – Jacob Barnes Jun 11 at 16:17
• Ultimately, I wasn't distinguishing between forces, because it seemed like energy is energy, regardless of its source, meaning whether centripetal or otherwise, I was thinking the increase in energy would change the state of matter for the ball of ice. I guess really I'm just curious about the interaction of matter and energy, etc. – Jacob Barnes Jun 11 at 16:19
• It is pretty clear to me now that I'm just too ignorant to even form my questions in a way that makes sense to those with the knowledge. I found this: goodtheorist.science and plan on just starting from the ground up so I have the tools to even communicate effectively. – Jacob Barnes Jun 11 at 16:21