Does Maxwell's Equations on Magnetic Field holds good in year 2020?

Question

Does "Maxwell's equations" on "Magnetic Field" still hold good in year 2020? Till now no parameters are changed or corrected?

Why does speed of Magnetism always relate to Speed of Electromagnetic Waves?

Answer 1

Yes, it’s still good.

Maxwell’s equation for the electric field is also still holding as well, as are the other two that tie together electric and magnetic fields. All four are good.

In fact, all four of the equations have been good for about 14 billion years. How do we know that? We detect microwaves that we’re confident were produced that long ago, and they obey his equations!

So you can expect Maxwell’s equations to hold in 2021 as well, and for the indefinite future.

The dude knew what he was doing.

I will leave it to others to explain how Maxwell’s Equations have been reinterpreted in terms of quantum fields to make QED and explain photons, how EM has been unified with the weak nuclear force as part of the Standard Model of particle physics, etc. Maxwell didn’t understand everything about EM, and probably neither do we today. But in classical form his equations stand today the same as when he formulated them about a century and a half ago, except for improvements in notation.

As for your last question, there is no “speed of magnetism”, only “speed of electromagnetic waves”. This is because there are no purely magnetic waves. All EM waves combine both electric and magnetic fields.