Hi Adam,
There is a reason why this discussion takes place in the "Frontier Physics" forum
. The truth is that we indeed have good theories that describe how things work - the most fundamental "what" questions is exactly what we're trying to answer with high-tech theories such the stringtheories. There are several variants, and to be honest, I don't think we're going to find out which one is the most correct anywhere soon.
I guess Max Planck could have been right when he said: "New theories do not prevail because they convince others and let them see the light, but simply because all opponents die out and a new generation, that is familiar with the theory, grows up"
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But no reason to be pessimistic: the theories we have explain a lot of phenomena in terms of basic assumptions on how nature works. Quantum mechanics assumes a wave/particle duality for everything in nature, and it works darn well. The questions we're asking ourselves here are in the line of: "is it REALLY both a particle and a wave?". Allow me to give a question as an answer: "does it matter? do we need to know that ?".
I think it doesn't matter and that we don't have to know all the answers to the "what is it" questions. Or like C'est Moi argued: "that is actually a wrong question". What most people seem to forget here (I also do that from time to time
) is that science CANNOT hold the absolute truth. Science works by inductive reasoning: from a series of experiments we try to formulate a general law that predicts the outcome if we do that series of experiments again. We can never verify this law to be entirely correct since that would involve doing an infinite number of experiments - anyone up for an infinite life? What science does is model nature in a scientific (read: mathematical) formulation, and a model is never perfect; simplifications are made, assumptions are made and if in the end, everything seems to turn out well, this model is used for describing nature.
The kind of questions science can answer are for example: "if I hold this pencil above my desk and let go of it, will it fall ?". The answer is obviously yes (no scientist will dispute that). But if you ask WHY the pencil falls, then you'll get a whole range of answers about gravity: "it's because of Newton's second law" or "the pencil follows a straight path in the curvature of spacetime". In the end, all these different answers relate to the different models of nature you use to describe the pencil falling (be it a Newtonian model of gravity, Einstein's general theory of relativity or an experimental theory of quantum gravity). The answer depends a lot on the scientist you're asking: does (s)he
believe the assumptions the model makes, does (s)he agree with the simplifications or does (s)he wants a more detailled description ?
So to conclude this part: the "why" and "what" questions are IMHO not answerable with science, only the "what if" questions.
You could be asking yourself why a certain model of nature (or theory) is more popular than another model. I believe that there's no consensus on that either
- as I quoted above, Max Planck thought it was a matter of time. Thomas Kuhn argued that no consensus is possible. Personally I think Henri Poincaré hit the nail on the head when he argued that the preference of one theory over another is simply a matter of convention: if both theories work, then it's up to the scientific community to decide which one they like to use. One of the best examples here is the theory of special relativity: you can use a perfect Euclidian world to describe relativistic effects (but that package comes with aether and unexplainable Lorentzforces that deform clocks and lengths) or you can use the Einstein/Minkowksi description which gives up the idea of aether, explains why clocks and lengths are deformed, but uses the assumption that the speed of light is a constant for all observers. Both theories work: they can both explain some of the wierd effects we see when going at high speeds. However, the scientific community choose Einstein's theory (probably because they didn't want those wierd deforming Lorentzforces to handle). But whatever theory becomes "mainstream" - it's entirely a human choice.
It's not really the most appealing image of science, but IMHO that's the way it is: because of our human inability to know "everything", we can never say something for sure.
Just my thoughts
Crisp