Possible alternatives to quantum theory that explain the double slit experiment? A lot of quantum theory has evolved to explain the double slit experiment with electrons and photons.  While fascinated by the quantum concept, I'm just a little skeptical as well.  Has anyone encountered a competing theory that also explains the double slit experiment without resorting to particles that act as waves?  For example, couldn't the same observations be expected if the particle was traveling through a field, and the observed path was a result of an interference pattern in the field instead of the particle interacting with itself through the slits?
 A: There is indeed a different interpretation of quantum mechanics, or if you want, a different approach to interpret the same equations. It's called De-Brogolie-Bohm-Theory or bohmian mechanics or Pilot-Wave-Theory which is an equivalent formulation of standard QM.
The essence is that this theory introduces another force-field the so called pilot-wave which is coupled to the particle itself. This force-field is responsible for the wave-like behaviour one encounters in some experiments because it "guides" the particle along its path.
Recently, there have been experiments with oil-droplets that are guided by a similar wave-like interaction, which show that the general results of the double-slit experiment and particles trapped inside a potential-barrier are compatible with their quantum-mechanical counterparts. However, this experiments are clearly on a macroscopic-scale, which previously was believed to be impossible.
For a better understanding I suggest reading this article: click
Also there are two videos I can recommend watching, to see the experiments in action: click1 and click2
This interpretation doesn't work with quantum-field-theory because QFT is not designed to describe particle movment but rather the dynamics of fields. Only later one introduces particle states that can be made to correspond to what we call a particle. However, if one allows a statistical interpretation of the process of quantization there is the possibility to introduce a similar pictorial view: Particles are statistical excitations of fields. The field's behaviour is wave-like. The exitations/particles are then "guided" by the field-dynamics.
A: 
While fascinated by the quantum concept, I'm just a little skeptical as well. Has anyone encountered a competing theory that also explains the double slit experiment without resorting to particles that act as waves? 

Particles don't act like waves in quantum theory. Particles are emergent properties of the wave function:
https://physics.stackexchange.com/a/237872/28512

For example, couldn't the same observations be expected if the particle was traveling through a field, and the observed path was a result of an interference pattern in the field instead of the particle interacting with itself through the slits?

That theory already exists. It is commonly called the pilot wave interpretation of quantum mechanics. It is described as an interpretation of quantum mechanics, but it really an alternate theory that in principle may make different predictions.
The pilot wave theory has severe problems. First, it puts particles on top of the wave function so it is more complex than quantum theory. It also does not explain anything that is not already explained by quantum theory:
https://arxiv.org/abs/quant-ph/0403094.
Second, it has problems with relativity, like all 'realistic' theories that try to match quantum mechanics (i.e. - theories in which all measurable quantities are represented by a stochastic variable):
https://arxiv.org/abs/quant-ph/0104062.
A: As @innisfree says in his comment

I don't think we need to be quite so defensive when people ask questions about established theories in physics. If the question isn't interesting to you, don't upvote it. If it's really bad question, downvote it. But don't feel obligated to offer hyperbolic defenses of QM just because alternatives to QM are mentioned.

To your question, yes there is alternative view (of mine) and it is similar (better in German kongruent) to your thoughts. There has to be an interaction between edges and photons and that should be described by their electric common field. This field has to be quantized and by this the deflection of the photons is not equally distributed. The manifestation of this is the intensity distribution, called fringes.
My similar question  "Can the intensity distribution behind edges and slits be explaint by the interaction with the surface electrons of the edges?" see here.
