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I'm struck with two competing ideas on the question in the title.

Listing #1: http://van.physics.illinois.edu/qa/listing.php?id=2009

Q: "How far can a magnetic field bend light?"

A: "Unfortunately, the path light takes is not affected by the presence of a magnetic field. Light itself is composed of an oscillating electric and magnetic field, and one very important property of electric and magnetic fields is what we call "linearity." That is, if you have two sources of electric and/or magnetic fields, you can predict what the combined field is just by adding the two source fields together. The two fields don’t change each other at all. "

Listing #2(Answer #1): Does electric charge affect space time fabric?

Q: "Does electric charge affect the space time fabric? If so, why?"

A: [See link. Rather, see both links if you must.]

I'm more inclined to consider the latter question and answer as the correct interpretation. Anyway, if anyone could help me out with this conceptualization that would be great, thanks.

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What exactly are you asking? It's not clear the way the question is written. –  David Z Jun 9 '13 at 3:45
I think by "ladder" you meant "latter" - anyway I edited it for you –  twistor59 Jun 9 '13 at 6:29
@twistor59 thanks, I was shorted by the "ladder operators " :) –  anna v Jun 9 '13 at 6:59

2 Answers 2

The first link you give the questioner wants to use magnetic fields to turn light in a circle, and is answered correctly .

You are asking about bending. In both of your links the answer exists that the magnetic field with its energy will contribute to the gravitational field about the source of the magnetic field and and might contribute to the observed gravitational lensing, and in that sense the magnetic field will contribute to the bending of light in gravitational lensing.

Think of geodesics. Light follows geodesics, straight if the gravitational sources are very small. The geodesic bends where the gravitational sources are strong ( gravitational lensing) . A strong magnetic field will contribute with its energy to the mass creating the geodesic, and that is all. The effect is very weak because the gravitational "interaction" is very weak with respect to the electromagnetic.

If you were thinking of the single photons comprising light then you have to go to the particle interactions and exchanges, where the rules follow quantum electrodynamics. In this frame the magnetic field will interact with a photon through higher order diagrams,( which means low probability).Photons can be scattered from virtual photons of the magnetic field , and change direction, which can be considered a bent ;if the beam photons have enough energy ( gamma rays) pair creation can appear.

Because these interactions are on individual photons, with low probability, the beam direction which depends on a huge ensemble of photons that comprise it will not change. It will just lose a few photons randomly in direction .

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Light changes direction when there is a switch in the medium through which it travels. For example, from air to water. Probably it is the density of the medium which matters. This is why you see waving images when looking over a hot car on a sunny day. If so, if one would create a sequence of progressively denser mediums, he could divert it considerably from its original trajectory.

Creating such sequence is a challenge. A sandwich of air streams of different temperatures? A sandwich of gases of different weights?

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