# A friend of mine who knows I believe in God but also put faith in

1. Mar 24, 2012

### Wingnuts

A friend of mine who knows I believe in God but also put faith in science that has been proven ordered me this t-shirt (see attachment).

And it's really sweet, but I don't want to wear something if I don't understand it...

I went searching, but the closest thing I've found so far is a wiki document for maxwell's equations, but they aren't quite the same as what is on this shirt.

Would someone kindly explain this, and is it a standard equation, or is it just one relating to lighting or electric light or light emitted by stars or what?

Thanks in advance for humouring my ignorance...

#### Attached Files:

• ###### Light.jpg
File size:
16.2 KB
Views:
130
2. Mar 24, 2012

### Staff: Mentor

Re: T-shirt

That's what they are, a version of Maxwell's equations. Solutions to those equations include electromagnetic waves, such as light.

3. Mar 24, 2012

### tiny-tim

Welcome to PF!

Hi Wingnuts Welcome to PF!

Yes, they're the integral form of the four Maxwell's equations, in free space (so εr = µr = 1).

See section 3 of the PF Library article

the differences are:

i] dA and ndS are the same thing, the vector representing a small element of area

ii] dS is wrong, it should be a small letter, either ds or dl (small element of distance) (S should mean a surface)

iii] Φ is the flux through the whole surface … so instead of ∂/∂t of an integral of E (or B) over surface S, your T-shirt has ∂/∂t of the flux of E (or B) through S … same thing

4. Mar 24, 2012

### Hassan2

Re: T-shirt

Here is the T-shirt: with the equations in differential form!

#### Attached Files:

• ###### T-shirt.jpg
File size:
13.2 KB
Views:
97
5. Mar 24, 2012

### Khashishi

Re: T-shirt

tis not wrong to use a capital letter, just less conventional.

6. Mar 25, 2012

### Redbelly98

Staff Emeritus
Re: T-shirt

It sounds like that T-shirt is perfect for you.

p.s. Welcome to Physics Forums!

7. Mar 25, 2012

### jim hardy

Re: T-shirt

Good for you.

I dont remember any commandment saying "Thou Shalt Not Think" .

Great message !

8. Mar 25, 2012

### vanhees71

Re: T-shirt

The integral form is correctly written in the special case of volumes, surfaces and boundaries of these at rest. The local (differential) form in the other posting is general. The only difference is due to the choice of units, which in the Ops case is the SI and in the white shirt's case in Heaviside-Lorentz units with $c=1$. I'd prefer the shirt. Even better were to write the equations in relativistic covariant form and Heaviside-Lorentz units since God for sure loves natural units and even more symmetry (and symmetry breaking, but this latter ingredient of the Standard Model not in the QED sector).

9. Mar 25, 2012

### Wingnuts

Re: Welcome to PF!

Thanks to everyone for the warm welcome and for the very helpful replies!

One thing is immediately clear: I know now what it's saying (because it's now been confirmed by the 'experts': the internets have, yet again, proven to be useful ) however, I still am not much further to *understanding* it. So, I have a steep learning curve ahead. Time to hit DeSlegte for a second hand physics 101 book.

This analysis, based on the following link to the library document, confused me. The dS is also written with a capital letter 'S' there too.

Is Khashishi correct that it is just less conventional to write with a capital S, or is S really 'surface', and therefore, not appropriate? Perhaps a vote is needed, or is that just pointless pedantry, because those who can read should know which one it is within context?

Cheers!

Last edited: Mar 25, 2012
10. Mar 25, 2012

### Wingnuts

Re: T-shirt

Thanks! Normally I would have to clarify my definition of 'proven', but I get the feeling that won't be necessary beyond saying that cargo cultists need not apply. To piggyback on Jim Hardy's delightful negative expression there, one of the actual commandments might be, "Thou shalt not produce nor accept dogmatically charged 'results'"

11. Mar 25, 2012

### Wingnuts

Re: T-shirt

You're all such a congenial bunch. Thanks!

I strongly encourage you to do just that. If you do, I'll get that shirt too and then will have options. For calm days, regular days and complex days (given your description, for when I'm feeling especially rebellious ) Seriously!

12. Mar 26, 2012

### tiny-tim

Hi Wingnuts!
No, in the Library article, every 'S' without a "dot" represents an area (with n dS = dA).

On the T-shirt, every 'S' comes with a dot", and represents a length, where the Library has "l".
If a friend gave you a T-shirt with "e = mC2", would you say that that was "just less conventional"?

13. Mar 26, 2012

### Wingnuts

Re: T-shirt

Ha ha ha. Very funny... Stepped right into that one, right? Now I see, the obvious (to me) clues as being c=1 and 'relativistic co-variant form'. No? Or have a I just made an even bigger fool of myself? Well, I did say I was clueless, which was an open invitation. I pray your next prey to be a little more worthy.

Now that I know the culture, I'll be a bit more careful where I tread.

Thanks for the help, guys.