Fields are theoretical constructs used to explain action at a distance. The constructs of gravitational field and magnetic field are well established and not controversial. Gravity does not have to send out any substance to a target object to affect it, rather it affects all objects within a distance, and this is conceived of as a field. Apart from these two examples, however, western science has been extremely hostile to the idea of fields, partly because it interferes with a tidy treatment of cause and effect. If fields are always around, effects are expected, but what then is the exact cause? And if effects are variable, how does one know the same field is in force?
In traditional Chinese thought, field based thinking has been the norm. Qi (chi) is a universal energy that figures in many fields. Two fundamental understandings about qi and certain conceived fields are that 1) they interact with living things differently than non-living things, and 2) they interact differently with different people according to the person's state of body functioning or preparation. How else can many differentials in health and disease be explained? But these two understandings have been anathema to mainstream western science, which is based on belief that human functioning and natural laws do not cross paths.
To be fair, the possibility that action and effect can be had at a distance by unseen fields allows immense room for fraud. Some of this is witting, but magical thinking is rarely totally extinguished in any adult, and what is magic if not action at a distance? Discernment between the real and false is possible of course, and in Chinese medicine is not considered a major issue. The usual giveaway to falsity is the assertion of casual or ad hoc manipulation of fields to accord with human will of the moment. Natural phenomena may interact with human bodies but they do not interact with human will--that is mysticism. But in the west, because this discernment requires subjectivity, the entire area is made taboo.
So in the West, only a few great thinkers have persisted with fields, however: Paraclesus, Mesmer, Jung, Reich. Alexander Lowen endorsed certain field phenomena but did not make them central to his work, because his work, like this website, was organized around practical means to decrease human suffering.
One common field concept is the human aura. Walter Kilmer demonstrated that anyone could train themselves to see auras by using purple goggles. This practice was revived by John Pierrakos, an associate of Alexander Lowen. From this it seems that auras are essentially in between visible and UV light. Distinguishing different colors within an aura has often been done diagnostically and may have validity but color in this context is interesting because it is not explained how UV frequencies have 'doubled' the color spectrum of visible light. In any case, the 'healthiest' colors are white or gold, which is the color of halos depicted around heads in early Christian art. In this early art, it was clear that the halo emanated from the head and there was no gap. In modern, graphic-design depictions of 'angels', halo are mere rings that hover above the head, like a sign of goodness that has been 'put there' rather than a biological function.