Originally posted by Turion
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Subject: the Bloch Wall
I feel there is a widespread misconception on this subject. So:
I keep up with UfoPolitics' forum, OUmachines.com, but am not a member, for a few reasons. I have interacted with UfoPolitics over the past 7 or 8 years. He is a member here, so hopefully he'll see this.
This chatGPT is an interesting thing. Opposed to having a "discussion" based on a difference of opinion (or interpretation) with a human, chatGPT doesn't get emotional. Most humans do.
So I've been at odds with UfoPolitics about the use of the term "Bloch Wall". Today on his forum he made a statement to which I object. Unable to confront him there, and never resolving the issue before, I decided to ask chatGPT. See below.
Another thing. UfoPolitics attributes the use of Bloch Wall to Dr. Felix Bloch. I have investigated this reading considerable amount about and from Dr. Bloch and have never seen "Bloch Wall" used in this context. Has anybody a citation of reference?
ChatGPT 3.5
User
Today I read on line this "All Magnetic Fields have a Center Plane, between Both Poles...North, South.
First one to identify this Plane as a "Wall" was Felix Bloch...reason why they name it after him the "Bloch Wall"."
________
It has been claimed that all Magnetic Fields have a Center Plane, between Both Poles...North, South. And that Dr. Felix Bloch identified this feature and hence it was named after him, the Bloch Wall.
Is this true or have any basis in physics or science?
ChatGPT
The concept of a "Bloch Wall" does have a basis in physics. It refers to a transition region between magnetic domains in a ferromagnetic material where the magnetization direction changes. This transition zone is where the magnetic moments rotate to align with the neighboring domains. Felix Bloch's work contributed significantly to our understanding of magnetism, but the term "Bloch Wall" is not widely used to describe the center plane between magnetic poles. It's more commonly associated with the transition region within ferromagnetic materials.
User
You did not answer the question. Need I repeat?
ChatGPT
Apologies for any confusion. The statement you read online about "All Magnetic Fields have a Center Plane, between Both Poles...North, South" and the connection to Felix Bloch naming it the "Bloch Wall" is not accurate. While the concept of a "Bloch Wall" does exist in physics to describe a transition region in ferromagnetic materials, it's not directly related to a center plane between magnetic poles in all magnetic fields. So, no, the statement doesn't have a basis in physics or science as presented.
User
Thank you. Is there any feature midway between the north and south poles of a magnet distinguishable from other areas of the magnet's material?
ChatGPT
Yes, in many magnets, there's a region known as the magnetic equator, which is roughly midway between the north and south poles. At this point, the magnetic field strength is typically weaker compared to closer to the poles. However, this region doesn't have a distinct physical feature like a "wall"; it's more of a transitional area where the magnetic field gradually changes.
User
How does the magnetic field change there?
ChatGPT
In the magnetic equator region, the magnetic field transitions from being directed predominantly outward from the north pole to being directed predominantly inward toward the south pole. This transition results in a decrease in the strength of the magnetic field compared to closer to the poles. The magnetic field lines tend to spread out more evenly in this region, leading to a weaker overall magnetic field strength.
User
I don't believe you. Please give sources or experimental proof.
ChatGPT
I apologize for any confusion. My response was based on general knowledge of magnetic fields. However, I cannot provide specific experimental proof or sources to support that claim. If you're interested in detailed information about the magnetic equator and how the magnetic field changes in that region, I recommend consulting scientific literature or textbooks on magnetism and magnetic fields. These sources should provide more comprehensive explanations and possibly experimental evidence to support the behavior of magnetic fields in the equatorial region of magnets.
User
I have studied what you recommended and never have seen the weakening of the magnetic field midway in between the poles inside of a magnet. Take a look at the field representation seen in FEMM diagrams. Can you do that?
ChatGPT
I don't have the capability to browse external content like FEMM diagrams. However, based on my knowledge, I can clarify that the concept of a weakening magnetic field at the midpoint between the poles inside a magnet might not be accurately represented in all cases. The magnetic field strength typically decreases as you move away from the poles, but it might not necessarily weaken significantly at the midpoint between the poles inside the magnet. Instead, it may remain relatively uniform in certain materials and configurations. I appreciate your clarification on this matter.
User
Knowing this, then is there any field transition midway between poles as you said? If so, be specific.
ChatGPT
In certain magnetic materials, there can be a transition region called the domain wall located midway between the poles. A domain wall is a boundary between adjacent magnetic domains with different magnetization directions. It's not a weakening of the overall magnetic field but rather a transition between regions with different magnetic orientations. These domain walls play a crucial role in understanding the behavior of magnetic materials, especially in ferromagnetic materials where magnetic domains can align to produce strong magnetic fields.
User
Does this domain wall occur between numerous domains throughout the entire magnet meaning the midpoint is no different, unless you have a two domain magnet, which is nearly impossible?
ChatGPT
You're correct. In most practical magnetic materials, the concept of a single domain wall occurring between numerous domains throughout the entire magnet is accurate. The presence of multiple domain walls throughout the material means that there isn't a distinct transition or feature at the midpoint between the poles. Instead, the magnet's internal structure consists of numerous domain walls, and the behavior of the magnetic field is more complex and continuous throughout the material.
User
Is it fair to say, observation from the inside of a magnet, one could not distinguish this midpoint between the poles from the field strength and direction only? If not, how then?
ChatGPT
That's a fair assessment. Observing the magnetic field strength and direction alone from inside a magnet, one wouldn't be able to distinguish a specific midpoint between the poles. The magnetic field would generally exhibit a continuous and complex behavior throughout the material, with variations occurring due to the presence of multiple domain walls and domain structures. To identify a specific midpoint or transition region, additional analysis beyond field strength and direction would likely be necessary, such as detailed magnetic domain imaging or other experimental techniques.
User
You keep saying that there is a transition at the midpoint. Transition from what to what? What is different on either side of this transition midpoint?
ChatGPT
I apologize for any confusion. Let me clarify. In a magnet with multiple magnetic domains, there isn't necessarily a distinct transition or feature at the midpoint between the poles. Each domain has its own magnetization direction, and domain walls separate these domains. The behavior of the magnetic field is continuous and complex throughout the material. So, there isn't a specific transition occurring at a midpoint between the poles; rather, the entire material comprises multiple domains and domain walls. The behavior of the magnetic field changes gradually across the material due to these domain structures.
User
Thanks, bi
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We can "observe" something, but whether the Bloch wall actually exists is a rhetorical question.
The mistake in treating visualisation - the image from a magnetic film held up to a permanent magnet - is simply to misinterpret what it depicts.
There are "bubbles" in the magnetic film that contain a planar particle with the appropriate magnetisation.
Depending on the vector of closure with the magnetic line, the particle is turned towards the observer: flat (dark part) or edge-on (light part).
The film shows the character of the force line vector only on the outside of the magnet body.
If the light strip, the magnetic lines crossing the film particles outside the magnet are strictly parallel to the magnetic vector between the poles in the body of the magnet.
And what happens in the body of the magnet is a very interesting question, which has not yet been practically checked by anyone (at least, which is available publicly).
Therefore, your inferences cannot be correct in any way. We don't know the truth yet.
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Originally posted by Rakarskiy View PostWe can "observe" something, but whether the Bloch wall actually exists is a rhetorical question.
The mistake in treating visualisation - the image from a magnetic film held up to a permanent magnet - is simply to misinterpret what it depicts.
There are "bubbles" in the magnetic film that contain a planar particle with the appropriate magnetisation.
Depending on the vector of closure with the magnetic line, the particle is turned towards the observer: flat (dark part) or edge-on (light part).
The film shows the character of the force line vector only on the outside of the magnet body.
If the light strip, the magnetic lines crossing the film particles outside the magnet are strictly parallel to the magnetic vector between the poles in the body of the magnet.
And what happens in the body of the magnet is a very interesting question, which has not yet been practically checked by anyone (at least, which is available publicly).
Therefore, your inferences cannot be correct in any way. We don't know the truth yet.
I know how magnetic viewing film works. And have some, and have used it for decades. Your description is good. Thanks.
Your last comment is illogical. Your premise that "We don't know the truth yet", infers that I CAN be correct. Which I believe is the truth. All evidence supports me, but sadly I am unable to prove such.
Regards,
bi
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