If all objects travel in straight lines unless acted on by outside forces, then why does light travel in wave patterns? What prevents it from simply traveling straight and not having wave properties?
The photon particle and the light wave are two different aspects of the same thing. By
AWT the vacuum is formed by elastic foam. Like each foam, the introducing of energy (the "shaking") into foam makes it more more dense. Even the single light wave (soliton or wave packet) makes the vacuum more dense temporarily.

While the light wave is undulating phenomena, the photon behaves like the dense blob of vacuum foam connected with the light wave packet. It has inertial properties, so it spreads like each massive body along the shortest path available. The energy of wave makes the photon massive, the inertia of photon gives the wave straight path due the Newton inertia law. Both these phenomena are in duality, while the photon (particle) character of wave is pronounced with the age of wave (see the right animation). The elementary particles, planets, stars or even whole Universe are just "pretty old" energy waves from this perspective.
Under deeper view, both the particle and wave spreading are nearly equivalent (the particle appears just as a more compact wave packet with another level of foam surfaces inside it) and they're supposed to be controlled by inertial diffusion of aether density fluctuations. This diffusion is fully gradient driven, so it always proceeds in perpendicular direction to the Aether density gradient. In fact, every movement is just a sort of slow dissolution of matter in field density gradient or certain sort of meta wave, because such dissolving is believed to be reversible and it leads to the accidental increasing of Aether density somewhere else by the same way, like the reversible precipitation and subsequent dissolving of density fluctuations.

What we see during massive body motion is pretty same picture, with the only exception: the density fluctuations are incredibly dense, more dense then we can even imagine. Due to its density these fluctuations are having a spongy character of negative curvature and they even highly recursive, while the foamy density fluctuations between normal particles having sparse blobby character with positive curvature.
In fact, the
AWT makes the understanding of Universe pretty trivial under assumption of infinite insintric Universe inertia/energy at the price. It seems, every logic in Universe understanding is balanced by the requirement of some crazy assumption, the more absurd, the more simple and logical explanation is used.
From this point of view, the belief in God is just a boundary example of such dilemma, because the assumption of infinite inertia and energy of Universe from the very beginning is not very different from pure belief in God with respect of violation of everyday causality. Even the Big Bang hypothesis suffers by this dilemma and the
AWT goes even much more deeper.
The more you want to understand the Universe on the background of everyday rules, the more you're required to believe in their violation during extrapolation into history and/or future. By such way, whole our understanding is based on inertia driven chaos-causality duality and it's undergoing the uncertainty principle by the same way, like the world of quantum mechanic.