Can a spinning mass without charge generate a magnetic field?

[kurious]

I read somewhere that a spinning mass with no charge creates a mass version of a magnetic field.Is this true?

 

[turin]

I read somewhere that a spinning mass with no charge creates a mass version of a magnetic field.Is this true?

It depends on how rigorous you want to be. Firstly, I suggest posting this to the Relativity forum, where you have a better chance of attracting people who know the answer and are interested enough to answer. I will tell you what I have read/heard.

There is a manifestation/form of gravitational interaction called "gravitomagnetism." I have seen no reason to doubt its existence. It follows naturally from a first order approximation of Einstein's equation. That is, the zeroth order approximation gives you Poisson's equation for Newtonian gravity (basically the F ~ r^-2 law), and the first order approximation is one order more accurate (so it includes more detail, like getting the kinetic energy from expanding the relativistic energy term of a particle). This first order approximation is also sometimes called the PN1 (Post Newtonian to first order) or the Maxwell approximation (I think).

Strictly speaking, this is not exactly like the magnetic field, even in analogy. In fact, it is only like this in PN1. Any higher (PN2, PN3, etc.) and you lose the analogy, so I've heard/read.

 

[R0man]

Yes, it is true that a spinning mass with no charge can create a magnetic field. This phenomenon is known as the mass version of a magnetic field, or the gravitational equivalent of a magnetic field. It is a consequence of Einstein's theory of general relativity, which explains the relationship between gravity and the curvature of spacetime.

When a mass spins, it creates a distortion in the surrounding spacetime, known as a gravitational field. This field can then interact with other masses, causing them to experience a force, just like how a magnetic field interacts with charged particles. However, unlike a magnetic field, which is created by moving charges, the mass version of a magnetic field is created by the curvature of spacetime caused by a spinning mass.

This concept has been confirmed by various experiments, including the Gravity Probe B mission, which measured the frame-dragging effect caused by Earth's rotation. It is also a crucial factor in the behavior of objects in the vicinity of rotating black holes.

In summary, while a spinning mass with no charge does not create a traditional magnetic field as we know it, it does create a mass version of a magnetic field through the curvature of spacetime.