physics #3

The best theory physics has to offer is known as 'the standard model'; it consists of quantum field theories on a classical space-time geometry and describes the physics of our world from elementary particles to galaxies.
It is obviously very useful, but is also known to be seriously flawed:
i) The quantum field theories become inconsistent at very high energies.
ii) The combination of quantum theories with general relativity is only an approximation, which breaks down in several cases, e.g. when the interaction between quantum fields and space-time cannot be neglected.
iii) The evolution of quantum fields leads to the superposition of macroscopic objects (Schroedinger's cat) and therefore the superposition of different space-time geometries. There is no agreement how to handle this and how to make sense of it, which is known as 'interpretation problem' or 'measurement problem'.

There is some hope that one day we can find a better theory and there are hints that a theory based on superstrings could solve the problems of 'the standard model'.
However, we are far from being able to perform experiments that would help us figure this out ...

The history of physics is a series of increasingly useful, but flawed theories.
It began with the epicycles of Ptolemy, followed by the classical physics of Newton et al., and finally relativity and quantum theory, culminating in 'the standard model'.
It is quite amazing how much our descriptions of the world changed over time; I think our attempts to resolve the flaws and inconsistencies of each era is mostly a struggle with our own biases ...