There was a reason why I constantly failed physics at school and university, and that reason was, apart from the fact I was immensely lazy, that I mentally refused to "believe" more advanced stuff until I understand the fundamentals (which I, eventually, never did).

As such, one of the most fundamental things in physics that I still don't understand (a year after dropping out from the university) is **the concept of [field][1]**. No one cared to explain what a field *actually is*, they just used to throw in a bunch of formulas and everyone was content. The school textbook definition for a field (electromagnetic in this particular case, but they were similar), as I remember it, goes like:

>An electromagnetic field is a special kind of substance by which charged moving particles or physical bodies with a magnetic moment interact.

*A special kind of substance*, are they for real? This sounds like the authors themselves didn't quite understand what a field is so they decided to throw in a bunch of buzzwords to make it sounds right. I'm fine with the second half but *a special kind of substance* really bugs me, so I'd like to focus on that.

### Is a field *material*? ###
Apparently, it isn't. It doesn't consist of particles like my laptop or even the light.  

If it isn't material, **is it *real* or is it just *a concept that helps to explain our observations***? While this is prone to speculations, I think we can agree that in scope of this discussion particles actually do exist and laws of physics don't (the latter are nothing but human ideas so I suspect Universe doesn't "know" a thing about them, at least if we're talking raw matter and don't take it on metalevel where human knowledge, being a part of the Universe, makes the Universe contain laws of physics). Any laws are only a product of human thinking while the stars are likely to exist without us homo sapiens messing around. Or am I wrong here too? I hope you already see why I hate physics.

###Is a field *not material but still real*?###
Can something "not touchable" by definition be considered part of our Universe by physicists? I used to imagine that a "snapshot" of our Universe in time would contain information about each particle and its position, and this would've been enough to "de[seralize][2]" it but I guess my programmer metaphors are largely off the track. (Oh, and I know that the uncertainty principle makes such (de)serialization impossible — I only mean that I thought the Universe can be "defined" as the set of all material objects in it). Is such assumption false?

At this point, if fields indeed are *not* material but *are* part of the Universe, I don't really see how they are different from [the whole Hindu pantheon][3] except for perhaps a more geeky flavor.

When I talked about this with the teacher who helped me to prepare for the exams (which I did pass, by the way, it was before I dropped out), she said to me that, if I wanted hardcore definitions,

>a field is a function that returns a value for a point in space.

Now this finally makes a hell lot of sense to me but I still don't understand how mathematical functions can be a part of the Universe and shape the reality.


  [1]: http://en.wikipedia.org/wiki/Field_%28physics%29
  [2]: http://en.wikipedia.org/wiki/Serialization
  [3]: http://en.wikipedia.org/wiki/Hindu_deities