Recent content by ia_

I've been waiting for someone else to reply, but unfortunately nobody has. From an economic perspective, physics is probably one of the most globalized careers in the world. Yes, manufacturing jobs may get sent to weird countries, but anyone anywhere in the world who gets good enough grades and...

If you wanted to consider a lagrangian with a nonzero photon mass in e&m, you could modify the lagrangian density from L = - \frac{1}{16 \pi} F_{\alpha \beta} F^{\alpha \beta} - \frac{1}{c} J_{\alpha} A^{\beta} by just adding a mass term: L = - \frac{1}{16 \pi} F_{\alpha \beta} F^{\alpha...

We're discusing MTW and the relativity book by Stephani in relation to the peer reviewed Nature article linked above. I'm just going to reply to Dale's post too. Semantics is not physics. Are you criticizing me because the English language wasn't designed to be purely relational? Come on.

Unfortunately page 5 isn't included in google's preview, but I think I see the idea from pg 6. MTW also has a preview. It seems like Stephani and Barbour are beginning with essentially the same process and using it in opposite ways. Stephani shows that the form of Newton's eq changes if the...

You misunderstood my position from the beginning. Where did I claim to make new predictions? Nowhere. Where did I propose a theory? Again nowhere. My initial post attempted to suggest what several of the fxqi essays, as well as a few of the papers by Barbour state. The whole point was that KNOWN...

Julian Barbour has a bunch of peer-reviewed articles, (for instance http://www.nature.com/nature/journal/v249/n5455/pdf/249328a0.pdf published in Nature 249, 328 (1974), and http://arxiv.org/abs/gr-qc/0012089 published in Class.Quant.Grav. 19 (2002)). What is your point? You decided I was...

Please just stop replying to my posts by trolling. All I expressed in the other post was a shortened version of what 3 or 4 physics professors choose to write about in the fxqi essay contest. If you're taking issue with the content of what I typed, you're taking issue with what they wrote...

I am not advancing any theory of my own. It's amazing that you're threatening to ban me... Perhaps you would be interested in reading some of the fqxi essay winners, by Julian Barbour (visiting physics professor at Oxford), Claus Kiefer (institute for theoretical physics at Univ of Köln), or...

Just for the sake of argument, I'm going to say that space is 3 dimensional, and time (although a useful convention) doesn't exist, because you can always substitute it out of your equations for any experiment by including your timekeeping device. i.e. A process does not take two seconds, a...

Special relativity is a subset of general relativity. In a region of space without large masses, the geometry of that space will become flat. That is, it will reduce to the minkowski metric of special relativity. So, all of the effects that occur in special relativity can also occur in general...

The equivalence principle states that an accelerating observer who has no external information (view of fixed stars, etc) can in principle not perform an experiment to determine whether he is either undergoing linear acceleration or at rest in a gravitational field. This leads to the equivalence...

Should I take a semester-long differential geometry course (in lieu of a thermo/stat mech course, which while not terribly challenging would prepare me for qualifiers, etc), or should I just jump into GR and maybe pick up a mathematical methods in physics course later? I first learned partial...