First I must show you how 'proof of existence' is actually an epistemological acrobatics if we allow the 'anything is possible' attitude of modern physics. Specifically, the knowledge of that which exist is actually an inference we make having at the back of the mind the assumption of cause and effect.The case should not be different for chi, auras etc. Whenever we see something that exist outside of our eyes, scattered light is involved. If we make the absurd claim that something can happen without a cause (a claim sometimes quantum physicist make) , I can deny that anything exists! I can say that the moon don't exist up there! What we see is a light being sharply bent by thin air without a cause! So for consistency purposes Delbruck Scattering proves the existence of an all pervading medium that is electrically polarized in the vicinity of charged particles, a litteral aura!
Next, let us see the problem with the lazy and cowardice 'not explicable by science' jocker card. The so called Krillian Photography is at times championed as a scientific proof of aura. But since such concepts as as 'auras' are stereotyped to belong to ' not explicable by science' all what a sceptic need to do is show that Krillian effect is due to electromagnetism. Then everyone nodes even though no one understand electromagnetism nor anyone can rule out the idea that perhaps it was electromagnetism after all that the ancients were referring to when they talked of auras. Specifically they try to show that Krillian Effect cannot occur without moisture as if they would believe in auras if we saw it happening in vacuum. They won't! Thanks to the 'inexplicable by science' stupidity. How can we know that something is inexplicable without being omniscient? Actually, Delbruck Scattering rebukes these epistemological nonsense. Even if we saw auras in vacuum, it would still not be 'inexplicable by science' because Delbruck Scattering does happen in vacuum.
Having seen that the seemingly empty space actually contains a real medium capable of interacting with our matter, we can now form a full blown spiritual theory that is scientifically plausible. First notice that in the vicinity of a living thing, such an aura will be so complex as to have a life of its own! This aura will contain all the information pertaining to the living thing. Next we see that such a polarized 'vacuum' can easily store the information even long afer the body is gone. The aura literally forms an 'etheric body'.
First notice that the aura in question polarizes the photonic medium. We know that this medium has solid-like properties such as the ability to propagate transverse waves. But why should the analogy with solids end with elasticity and stiffness? Why not another feature common to all solids termed 'plasticity'? If we think this way, we will be truely thinking like James Clerk Maxwell which let him infer electromagnetic waves. If the space around magnets behaves as if there is fluid, then it must also behave as if there are waves. If the whatever thing causing magnetism behaves like water in that it can drag something, then tge analogy extends to the behaviour of water that creats waves in it.
But what if we indeed see a scattering in vacuum away from the objects. Will they make the above inferences? Nope! They will just call it some fancy name such as 'Franklin's Scattering' and go on oblivious to the fact tha the discovery is actually far reaching. After all 'auras are inexplicable by science' is the main lesson 'gurus' teach. This guarantee that if you are a scientist you have no eyes for these for all discoveries actually involves explanations, inferances and understandings. So it is even sensible to wonder if perharps they have made such discoveries without notice. The answer is yes! They have noticed, for instance, that light from distant stars slows down as if they interact with something even in apparently empty space.
Another example is the so called photon-photon scattering. First understand photon as a polarization of vacuum that is propagated as a wave. Light reflecting off anither light is actually a proof that light travels in a medium. If we deny this, then we are using a definition of 'proof' that can make me say with confidence that there is no proof that tge moon exist. Anything that reflect, refract or scatter light better be defined as an existent entity! Light from reflected objects is all we get as 'evidence that something exist' at the region from where the light is reflected