12 Comments
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Green Mojave's avatar

I’ve always found the near field - far field transition in antenna design a true paradox.

Hans G. Schantz's avatar

I'll be talking about the near field-far field transition at length throughout Fields and Energy, mostly in Chapter 8. If you can't wait, here's a talk about the history, physics, and wireless applications of low-frequency, long-wavelength systems that use the properties of the near field-far field transition.

https://www.youtube.com/watch?v=3HGvJ9HtWzk

ScuzzaMan's avatar

I do greatly appreciate Maxwell's style. He writes with great clarity and without excess.

"Space-time tells matter how to move; matter tells space-time how to curve." - as John Wheeler summarised Einstein.

If "space-time" is a persistent nothing, then:

"Nothing tells Matter how to move; Matter tells Nothing how to curve."

It seems to me that there is Something missing in this accounting. I am very open to the proposition that what is missing is in my apprehension of the points under discussion. Also looking forward to the next instalment.

Hans G. Schantz's avatar

Parmenides (~515 BC): "Out of nothing, nothing comes." Ancient wisdom.

ScuzzaMan's avatar

My great friend and mentor Doug B used to tell me:

"Nothing for nothing, everything for a reason."

He'll be tickled by this quote.

Thank you.

Steven L.'s avatar

I will read this with interest. Is this literally verbatim of what Maxwell wrote?

Hans G. Schantz's avatar

Yes. Literally and verbatim, except for the figures and the comment on the modern accepted value for the speed of light.

Here's the source: https://archive.org/details/scientificpapers02maxwuoft/page/310/mode/2up

Steven L.'s avatar

Thank you. I will try to find the time to read this. One of the things that I have always struggled with in learning physics (and math) is that too often its taught as abstract ideas, without much background or historical context. If you have some context and history, its often easier to understand.

Jim Nealon's avatar

One of the difficult but satisfying things was to derive answers to Maxwell's equations, in terms of real or practical items like current flow or light propagation. Abstract terms, vectors, and fields were easier to understand.

Jim Healy's avatar

And History becomes people and events as opposed to dates and places

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May 3, 2024
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Hans G. Schantz's avatar

That's certainly the conventional wisdom.

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May 3, 2024
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Hans G. Schantz's avatar

I misunderstood you.