Just by considering the known details that have been measured and described of the forces in relation to the subatomic organisation of matter into the atoms and molecules of the elements and compounds as well as the species of living organisms it could be asked:
Can a physics of the forces alone explain how the universe is the way that it is?
That is, a physics where the evidence can be considered to indicate that, universally, the world that includes all life on Earth consists just of its smallest parts, and the forces that surround such subatomic components of matter?
Or if it is supposed that there could be a scientific account that may be called a 'theory of everything', it could be asked:
Shouldn't such a theory explain how the universe is the way that it is despite the evidence indicating that the universe is made just of it's smallest parts and the forces that surround such subatomic components of matter?
So that it could be wondered whether the evidence of matter and radiant energy on the smallest scale indicates that, to explain how matter can be and remain in all its atomic and molecular forms and despite the forces, enough details somehow need to be found and described of a further cause that would act in a quite different way to all the forces?
For one can just point out that the experimental evidence indicates that matter in general as atoms and molecules consists almost all of the space between its universal components called electrons and atomic nuclei and that the powerful charge force is measured to attract between the electrons and nuclei and repel between the electrons. Hence it can be asked: given the action of just this force between these subatomic components, how can matter be and remain organised as atoms and molecules, and so how could matter in any observable form exist or persist at all? Doesn't matter in general, somehow, exist despite the forces acting within it?
Then the thought could be that, at least just from any kind of experimental evidence that has been found of atoms and molecules and their subatomic components, it is not possible to find a clear and adequate answer to these questions in any case. The reason being basically that such an answer would require certain behaviour that has been measured and described of the subatomic components of matter to be clearly explained as the effects of a distinct cause that would act universally in addition to all the forces. And the universal action of this cause upon atoms and molecules would be just to maintain or conserve their forms and subatomic organisation.
The quantum behaviour that needs to be causally explained is that which has been uniquely described of quantum objects and has been found impossible to directly observe or measure from objects in motion in any experiment. So it has been open to question as to whether this quantum behaviour actually exists beyond the experimental results or if it does exist, whether it has any cause at all or, at least, has any cause that could be described in clear and detailed enough terms from it effects. This behaviour has been called quantum wave, spin and entanglement.
So physicists these days, at least, generally suppose that quantum entanglement - which is an effect that has been measured and described as occurring at a distance between both photons of light and between matter particles as components of atoms - has no cause.
The entanglement effect has no measurable strength and has not been measured to reduce, cease or weaken in any way with increasing distance between objects and so has been called non-local to distinguish it from the local effects of all the forces. So that any cause of quantum entanglement could not be described as surrounding objects like the forces that act at a distance, also called the fundamental interactions, such as gravity and electromagnetism or the charge force. The record distance that entanglement has been experimentally detected so far is 90 miles or 144 kilometres between beams of light, as measured in a recent experiment in the Canary Islands.
However, it can be pointed out that what can be measured as effects between quantum objects are relationships or correlations between certain forms of behaviour. So electrons as components of atoms can be described as being in entangled pairs where the correlation of behaviour is spin up in one particle and spin down in the other. And thus one can insist that, while no pull or push or attract or repel cause can be measured, there needs to be some cause that maintains these correlations.
Then the thought could be that while a non-locally acting cause of quantum entanglement could not be described as surrounding objects in three dimensional space it could act in additional spatial dimensions to the three in the world we experience. And although a cause acting in any such extra dimensions could not be directly represented, such a cause acting upon two quantum objects in one such extra dimension could be represented three dimensionally as follows: So that here the non-local quantum entanglement cause is represented as acting from a third dimension upon two dimensional objects in a two dimensional world and so without surrounding the objects. Although reasons can found to consider that the entanglement of two or more quantum objects would require a cause to act from two extra dimensions of space.
For a detailed quantum hypothesis that is considered in relation to large scale observable natural evidence see: