Monday, November 09, 2009

Physicists, Take Note

I read a book about James Clerk Maxwell, and now I am almost a Maxwellian. So I'm determined to tell you all everything you DON'T know about JCM.
Okay, so before I started this book I knew that Maxwell had come up with some equations and talked about light a little, and that this helped Hertz discover the photoelectric effect and....the consequences go on. But while Maxwell got ONE page in our textbook, he did SO much for physics that we didn't get told. Okay. Basic summary, Maxwell did for electromagnetism what Newton did for gravity.
Before Maxwell's equations, the only fully developed, complete and mathematical theory in physics was Newton's universal law of gravitation. So, everyone was trying to apply its basic form to electricity etc. And it worked, but they had this weird view. 'Newtonians' believed in action-at-a-distance. i.e. that the space around a magnet is empty with regard to the action of the force, which when iit acts between say a nail and magnet leaps across the space between them without affecting that space. Now, I don't quite get this, its a weird concept but, do you know why its strange? Because of Faraday and Maxwell.
So, Faraday, armed only with basic geometry, developed the idea of a magnetic feild, which Maxwell took and hammered away on to get his equations, and eventually the field idea was accepted, when proof came for Maxwell's equations i think, and now we get it, and don't get action-at-distance. In the process of developing a way to describe mathematically the relationship between electricity and magnetism and Faraday's fields, Maxwell took the recent idea of vectors and used it, thus naming many operations involving vectors, including the curl and divergence. Plus, the curl is pretty much the right hand grip rule - how you determine the direction of a magnetic/electric field. So awesome.
Maxwell was also the first to develop a completely mathematically based theory, or like one without a physical image or analogy. Whilst physicists are used to such use of maths now then they wanted more concrete images to work with. Maxwell's equations have had enormous ramifications too. They are behind many many technologies we now use, and play a vital role in quantum electrodynamics. Maxwell also came up with the basic idea for the Michaelson-Morely experiment, and his equations have been found to be applicable at relativistic speeds and on the quantum level.
I hope you followed all that. You really have to read the book to really get how significant this guy was, I think. Not that I really understand half of what I just talked about (quantum electrodynamics, for instance), but I have a new appreciation for this guy who appears to be on the same level as Newton and Einstein. Also, the book is like a biography as well, so you get a glimpse of what the guy was like which is also cool. One of the funniest things I found was his group of friends' nicknames for each other. So, Maxwell's nickname was dp/dt because dp/dt=JCM, JCM being his initials - as the author says a 'mathematical allusion or in-joke" which simply humorously understates the wonderful geekiness of it (for want of a much better word.)
And that is what I've learnt. I don't think I really communicated much of what I wanted to, spent more time on Newtonians etc, but whatever. My blog needed a post and I needed an outlet other than my family, wouldn't care, so you are stuck with this mess of facts instead. Sorry they're terribly organised, they just spilled onto the page, so to speak.
I'll try and be more relatable next time.


Eric said...

so youre finished it?!

sounds VERY interesting. He's obviously your first dead crush =P
but really, it makes me so keen to find out what we dont know about so many other scientists!

and you made sense. physics is cool, you like physics, which makes you cool (but im sure for other reasons too :P). im so keen to read this. then we can both get excited about it, and you'll have someone to talk to about it. Though i did quite enjoy that last night too.



Stephen said...

its ok, geekiness is an excellent word.

alsp, i dont understand that maths behind the dp/dt thing...

| : alyssa : | said...

But its not the word i wanted.
And i think dp/dt=JCM is maths beyond what we've learnt. Hence your not understanding it. Its just an equation that is used for something. I have no idea what.