# Light as a Relativistic invariant

Hey guys,

I know this subject is a bit of an old chesnut but i thought id ask it anyway.

What logical steps did the various physicists take to realise that c was constant in all reference frames? Ive sort of found some weird ways to justify that fact in my head, but its more reverse engineering than actually arriving at it from nothing.

Id like to know how these guys game up with this, was it just lortenz's work or something more.

Thanks
-G

Chris Hillman
Einstein, in a word

What logical steps did the various physicists take to realise that c was constant in all reference frames?

Actually, that was all Einstein. Two good books:

Abraham Pais, Subtle is the Lord, Oxford University Press, 1982.

Peter Galison, Einstein's clocks, Poincare's maps, Norton, 2003.

At the risk of sounding impatient could you not put it in a nutshell for me? I already have einstines original book on SR and GR so ive got most of the basics down.

At the risk of sounding impatient could you not put it in a nutshell for me? I already have einstines original book on SR and GR so ive got most of the basics down.

No you don't. The types that misspell his name the way you did and who use lower case don't know (and don't deserve to be taught).

No you don't. The types that misspell his name the way you did and who use lower case don't know (and don't deserve to be taught).
That's a bit harsh, isn't it? It's common on the internet to not capitalise proper nouns (this is partially due to URLs not being case sensitive, and partially laziness). As for the misspelling, we are not yet sure if it's a typo or a case of ignorance.

could you not put it in a nutshell for me?
Once convincing argument is that according to Maxwell's equations, the speed of light is c in all inertial frames. Another way of saying the same thing is that Maxwell's equations aren't Galilean invariant (which was assumed to be the invariance of the universe until the Lorentz group was discovered).

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Chris Hillman
Thanks, masudr!

And FunkyDwarf, don't worry about nakurusil; speaking for myself, I know I can get a bit cranky at times.

To some extent this might be a function of not knowing whether one is addressing a graduate student (whom one would expect to follow up citations by reading the books mentioned), or a younger person who might not yet appreciate the "scholarly ethos" (according to which it could be considered a bit rude to demand that I summarize a book for you). But don't worry, I am not holding you to that because I am assuming you didn't know this.

HallsofIvy