I believe special relativity because it’s implied by Maxwell’s equations, which I have experienced. Normal human speeds are enough to detect contraction, if you do it by comparing E&M.
Does anyone know how to do this?
Looks like Douglas_Knight2 hasn’t been here for a while, so he probably isn’t going to say. I don’t think the path ahead of me is going to have its colors shift as I run faster, so the simplest approach isn’t going to work. This would be a really cool science experiment if it were really possible.
I have a vague memory from an electrodynamics course more than twenty years ago that the electromagnetic field is a four-vector that transforms the same way that spacetime vectors transform under boosts.
So what in Victorian physics were two separate things became components of one thing, in the same way that space and time merged into spacetime. And Maxwell’s four equations in three dimensions + time became two equations in spacetime.
With the old physics, if you had two stationary charged things, they’d attract each other by means of the electric field and there would be no magnetism involved.
But two things moving side by side (i.e. the same situation but you’ve changed your idea of what it means to stop), attracting each other in exactly the same way, had to be explained by saying things like ’a moving charge generates a magnetic field, and the other charge, moving in a magnetic field, feels a force.
Another way of saying that is that by moving, you can turn electric fields into magnetic fields.
In relativistic physics, there’s just the one thing, ‘the electromagnetic field’, and your motion affects your measurements of the two different components, in much that same way that there’s only ‘spacetime’, and your motion affects your measurements of space and time.
Because the electric and magnetic fields are so strong, this interchange is perceptible with simple instruments at low speeds.
It was all a long time ago. Perhaps a passing physicist can explain better or correct my flailings?
I believe special relativity because it’s implied by Maxwell’s equations, which I have experienced. Normal human speeds are enough to detect contraction, if you do it by comparing E&M.
Does anyone know how to do this?
That seems rather bizarre. Was he making some kind of joke? Humans aren’t fast, heavy, small or sensitive enough to notice anything that that advanced happening to ourselves.
It takes very low speeds to see macroscopic magnetic effects from electric charges. I’m not sure that that ‘implies special relativity’, because it’s also consistent with the previous theory. But from a relativistic point of view, that’s a relativistic effect of much the same kind as time dilation/length contraction.
Does anyone know how to do this?
Looks like Douglas_Knight2 hasn’t been here for a while, so he probably isn’t going to say. I don’t think the path ahead of me is going to have its colors shift as I run faster, so the simplest approach isn’t going to work. This would be a really cool science experiment if it were really possible.
I have a vague memory from an electrodynamics course more than twenty years ago that the electromagnetic field is a four-vector that transforms the same way that spacetime vectors transform under boosts.
So what in Victorian physics were two separate things became components of one thing, in the same way that space and time merged into spacetime. And Maxwell’s four equations in three dimensions + time became two equations in spacetime.
With the old physics, if you had two stationary charged things, they’d attract each other by means of the electric field and there would be no magnetism involved.
But two things moving side by side (i.e. the same situation but you’ve changed your idea of what it means to stop), attracting each other in exactly the same way, had to be explained by saying things like ’a moving charge generates a magnetic field, and the other charge, moving in a magnetic field, feels a force.
Another way of saying that is that by moving, you can turn electric fields into magnetic fields.
In relativistic physics, there’s just the one thing, ‘the electromagnetic field’, and your motion affects your measurements of the two different components, in much that same way that there’s only ‘spacetime’, and your motion affects your measurements of space and time.
Because the electric and magnetic fields are so strong, this interchange is perceptible with simple instruments at low speeds.
It was all a long time ago. Perhaps a passing physicist can explain better or correct my flailings?
That seems rather bizarre. Was he making some kind of joke? Humans aren’t fast, heavy, small or sensitive enough to notice anything that that advanced happening to ourselves.
It takes very low speeds to see macroscopic magnetic effects from electric charges. I’m not sure that that ‘implies special relativity’, because it’s also consistent with the previous theory. But from a relativistic point of view, that’s a relativistic effect of much the same kind as time dilation/length contraction.