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I am religious and believe in free will

70 (27.6%)

I am religious and do not believe in free will

10 (3.9%)

I am not religious and believe in free will

113 (44.5%)

I am not religious and do not believe in free will

61 (24%)

Total Members Voted: 249

[thompson]

If anyone asks you why you believe Magnetic Jesus exists, you can always point to a pair of magnets and say "if he doesn't, how do you explain this?"

The wonderful thing about magnets is that if you actually know physics well enough to describe their basic operating principles, your attempts to explain them to ordinary people will sound even more far-fetched than "motherf'n magic".

God couldn’t figure out what else to do with vector cross products. It’d have been a shame not to use them.

[Teneb]

The Magnet pulleth and the Magnet pusheth away.

[thompson]

Do not preach of this false messiah Magnetic Jesus! For in the Book of Lorentz it is told the Electrodynamic Force is but a heresy of those who move not in Thine Almighty Frame, but instead live in sin with relative Velocity to Thee. Listen not to the deceivers who preach Idoltry of monopoles and their false Forces, but instead accelerate to Thee, and be eternally at rest in Thine Frame. For there is no Force but Coulomb, and Einstein is his Prophet.

[HmH]

It might seem like the one-system-of-reference approach of electromotive fundamentalism offers a less complicated approach to things.
But as soon as those two charges start moving, which is immediately, you gain velocity relative to at least one charge. So for Coulombists even their own 'only holy force' turns into what they claim to be sin - and it does so as soon as it appears.
The Coulombist approach, in other words, is self-contradictory. It is only internally consistent in one case: on paper.

[thompson]

Blasphemy! Those who travel in the True Frame co-move with Thee and have a velocity of zero, so are not subject to your heathen forces. Sinners may be deceived by the False Force, but the Faithful never are.

I mean, you can use B-fields as a convenient abstraction, but is it really worth an eternity in Non-Euclidean Hell? Apparently all forces are orthogonal there. It’d be really f’ing annoying.

[HmH]

The concept of any True Frame where two objects moving in opposing directions have zero velocity relative to each other is contradicting the very idea of a frame of reference.

And, truth be told, if I had a choice between a non-Euclidean "hell" and a so-called "frame of reference" where objects moving towards each other don't grow any closer, I'd choose the former.
At least in non-Euclidean topology, you can figure out how to move so that you'll actually get somewhere.
UPD: Now that I think about it, there is one rather exotic frame of reference where two equal and opposing charges have zero velocity relative to each other: the one where space itself stretches between them.

But as spacetime expansion is dependent on the distance, that is only possible when every object has its own equal and opposing charge that is located at a certain fixed distance from them.
Alternatively, we might consider the more fundamental spacetime dilation that is dependent on changes in velocity; but then, as well, each True Frame is only true for one pair of charges moving at a given velocity with given acceleration relative to the rest frame.
And if we assume either of those, we will have to admit that there is an infinite amount of Unmoving Charges - one for every possible point in space (or one for each combination of velocity and acceleration) - and therefore, an infinite amount of True Frames.

Which, in turn, means that in every True Frame, other charges, each within their own True Frame, will move relative to us and Coulomb's force will be insufficient to describe our interactions with those charges.
Which is precisely why Magnetic Jesus is a necessary part of any worldview, even that of electromotive fundamentalism.

[McTraveller]

This does all make you wonder - why do things change?  For motion or any of physics to make sense at all, it means that "something" must change.

[Naturegirl1999]

This does all make you wonder - why do things change?  For motion or any of physics to make sense at all, it means that "something" must change.

the search for entropy

[TD1]

How do you know things change? I posit two alternatives: One, it is only our perception which changes, and our perception is flawed.
Two, we operate within a constant known as the 'present'. The present never actually changes; it is always the present. The illusion of alteration comes when many snapshots of the 'present' (now called the 'past') come together. It is like watching a film composed of many frames. Each is its own self-contained constant. Together they create an illusion of movement. But in reality, all is static.

[HmH]

Why wouldn't things change?

You've got a really energetic (and therefore unstable) molecule.
It can become a little less energetic by shifting to a lower energy level and throwing the energy difference away in the form of a photon.
And each separate molecule tends to be more stable the less energy it has.
So why wouldn't it emit a photon and go into a more stable state?

[thompson]

HmH, you’re missing my point. If you’re carrying an electric charge but are not moving, there is no magnetic force acting on you. It doesn’t matter what other charges exist in the universe or how fast they are going: B x v = 0.

Now, your point about the True Frame is a little more complex and depends on which sect you belong to. The Lorentzians believe that there is but one True Frame, and to live in any other frame is to reject the divine. The problem, however, is that no one is really sure what that frame is, so naturally the sect has been rife with schisms and internal strife.

Seeing this, Electric God sent the Prophet Einstein who preached that there is no one Universal Frame, but rather that we must all be true to our own personal True Frame. Incidentally, that True Frame is the frame where we are at rest with the Divine. So, you need to calculate the Force of each particle in its own rest frame.

Then there are the Machians, who say that one’s True Frame is relative only to everything else, but no one is entirely sure what that means.

In any case, magnetism does appear to be a dynamic effect of the Coulomb Force and could be illusionary in the sense that the centrifugal force is illusionary in a dynamic rotating system. It’s probably due to some finite propagation speed of the electric field which gets messed up once it’s no longer spherically symmetrical after Doppler shifting. So, you can still kind of “eliminate” magnetism conceptually with relativity even if you measure all particle dynamics in a single frame, but dynamical effects are harder to model and working on non-spherical fields only complicates it further. Introducing magnetic fields works because the system obeys Lorentz symmetry, which reduces to Maxwell’s equations in a single frame. Needless to say, monopoles cannot exist, even in principle.

[McTraveller]

If the universe is a set of static "present" moments, then what causes perception to shift between the moments to give the illusion of motion?

What causes energetic systems to seek their lowest-energy states*?

This is what I meant by "what causes change".  Another question is probably like it: "why is there energy?"

*

Spoiler (click to show/hide)

I'm well aware that this is an emergent effect: systems tend toward their lowest-energy, highest-entropy states because those are the most probable configurations given that configurations change.  But no modern theory says why things change in the first place.

[Naturegirl1999]

Energy spreads out, matter is very very condensed energy. The universe as we know it used to be a dense area of energy that began expanding, eventually creating the forces and particles that exist now

[HmH]

HmH, you’re missing my point. If you’re carrying an electric charge but are not moving, there is no magnetic force acting on you. It doesn’t matter what other charges exist in the universe or how fast they are going: B x v = 0.

Except if outside magnetic fields shift relative to a static charge, a force is exerted the same as if the charge was moving in that magnetic field.
So even in a frame of reference where one of the charges is static, charges moving next to it would still exert a force whose vector is not collinear to what Coulomb's force vector should be.

Case in point: electricity generation is all about forcing relatively static electrons within a conductor to move by exposing them to a changing (i.e. moving) magnetic field.

[McTraveller]

Ehhh... there's a reason it's called the electromagnetic field.  It's a single field and it just looks like two effects in any given reference frame.  The canonical example is parallel current-carrying wires: from the frame of reference of the electrons, the length contraction in the other wire causes an apparent higher negative (or positive) charge density in the other wire (depending on which direction the currents are flowing), which if you do a static analysis gives you the exact same force as using the "magnetic" field in the frame where both wires have current.

Yes the length contraction is small, but the charge constant is huge - so you get a "human scale" force for human-scale currents.  Pretty fantastic really.