What will happen if I assemble magnets with flush joints and the same polarity?

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Discussion Overview

The discussion revolves around the theoretical assembly of magnets with flush joints and the same polarity, specifically focusing on the implications of such an arrangement in terms of magnetic properties. Participants explore concepts related to magnetic fields, coercivity, and potential outcomes of the assembly process.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant describes a gedankenexperiment involving the assembly of samarium-cobalt magnets with the same polarity, suggesting that the assembly could lead to a unique magnetic configuration.
  • Another participant challenges the feasibility of the assembly, arguing that it would result in a non-magnetic structure and questions the behavior of magnetic field lines when the pieces are glued together.
  • A follow-up response emphasizes the high coercivity of the material and proposes that the magnetic field lines would still be present despite the assembly, leading to a complex interaction within the assembled structure.
  • Some participants introduce the concept of a Dirac pipe, speculating on how magnetic flux might behave in the context of the assembly, while also engaging in light-hearted banter regarding terminology.
  • There is a suggestion that the final assembly could potentially behave as a magnetic monopole, raising questions about the nature of monopoles and their theoretical implications.

Areas of Agreement / Disagreement

Participants express differing views on the magnetic properties of the assembled structure, with some arguing it would be non-magnetic while others propose alternative outcomes, including the possibility of monopole behavior. The discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Limitations include assumptions about the behavior of magnetic fields in assembled structures, the effects of coercivity, and the theoretical nature of monopoles. The discussion does not resolve these complexities.

danR
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I cut some magnets into buckeyball-faced polyhedra and bond the pieces together so that all joints are completely flush. Assume the joints are perfectly planar-flush, and bonded with a monolayer of something with a small molecular size. Or better yet, the thing is assembled in a vacuum and the unoxidized faces bond together directly

The pieces all have with the same polarity outward.

What do I have?

Edit:The material is samarium-cobalt with very high coercivity. Just to make isolated local domains a wee bit harder to posit as the outcome.
 
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You haven't actually done this, because if you had you would notice that what you built is fairly non-magnetic.

Draw the field lines of the pieces. Where do the field lines go when you glue them together?
 
Vanadium 50 said:
You haven't actually done this, because if you had you would notice that what you built is fairly non-magnetic.

Draw the field lines of the pieces. Where do the field lines go when you glue them together?

1. Of course I haven't done it. It's a gedankenexperiment.

2. You tell me. It's high coercivity samarium-cobalt. Those lines will not be so easily dissuaded by mere assembly. Assembly can proceed several ways, but if I start by joining one piece to another, I have a somewhat wider single (slightly curved) plate-magnet with a north on one side of the plate and south on the other and the lines of force curving fairly normally around the entire assembly.

Continue from there, step by step. Eventually the pieces and the electrons and the lines of force start to realize: 'Hey, we've been duped!'

But it's too late. We have a ball with a North outside, and a South trapped inside.

Edit: I assume you will answer we have a rather warm metal ball with no magnetism whatever.
 
Or a Dirac pipe will form to let the flux flow from the North pole to the South.
 
Blibbler said:
Or a Dirac pipe will form to let the flux flow from the North pole to the South.

I didn't know Dirac smoked a pipe. You're thinking of a Bohr pipe?

C'mon, I want a serious discussion! If we assemble the sphere to the point of one segment missing, then we can picture the outside flux all curving around to inside the remaining hole. No problem.

What happens when we bond in the last piece? The field intensity is almost as high at the edges of each segment as its middle, the coercivity is high. Obviously we'll need a vise to ram it in, and perhaps the whole thing must be wrapped in duct tape. That would obviate the need for glue.

Since magnetic monopoles are not forbidden, and appear to answer much, I see no theoretical reason why the final assembly would not be a magnetic monopole. Does anyone say a monopole has to small? That it must be a single particle?