Permanent

Little known fact:

• "Permanent magnets 'significantly' stronger than those "commercially available" are known and can be manufactured."

What limits Neodymium grade "N52" as the "best" we have now?

Fragility.

The stronger the permanent magnet, the more fragile it becomes.  An individual might intuit more powerful means "tougher".

That intuition would be backward.

Can't that be "engineered" around?  The answer is "maybe" or no.

Every magnetic field contains an electric field.  For both electromagnets and permanent magnets, a stronger magnetic field equals a stronger electric field.

How is that known for a fact?

The answer is an "unopen" secret.

Permanent magnetics that have been produced above "N52" can be so fragile that:

• Placing one on a table can shatter it.
• Leaving one under the "wrong" kind of light can shatter it.

What does this tell an individual paying attention?

Resonant light "collapses" an electric or magnetic field. "Stronger" fields collapse "harder".  This might lead to a comparison with gravity.

Which would not be backward.