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We have discussed optics and acoustics of ghostly manifestations (see Physics of ghosts 101: The introduction and Physics of ghosts 101: part I – Optics, part II and part III- Optics and acoustics), but what can I say about a ghost, which appears with smell of a rotten flesh? How did that one conjure molecules of ptomaine so the witness could actually smell it? I admit, I have no slightest ideal However, there are some possibilities.


 
 
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PHYSICS OF GHOSTS 101: PART TWO - OPTICS  I was talking about colors of ghosts. I just went through the gallery of ghost photos in Janet Bord, The 100 Greatest Photographs of the Paranormal from The Fortean Picture Library, from the publishers of #Paranormal and I didn’t See any color picture where ghost would appear in its own color! They all look like semi-transparent monochromatic objects, while their colors are projected from the objects on background (leaves from the trees, church furniture, etc.). Yet, I do believe I’ve seen ghosts in color myself, at least twice. And there is a plenty of written witnesses of that kind. 

 
 
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The previous post PHYSICS OF GHOSTS 101: PART ONE - OPTICS was concluded with the notion that in terms of optics ghosts likely act as gray (black) bodies, which explains their appearance / disappearance acts, depending on their thermal energy and major spectral characteristics lying likely in near IR area of a spectrum. The latter needs some extra comment.

I will start with a simple fact: the ghosts are gray bodies (in optical terms, not in the terms of appearance). This looks like a plausible explanation to many witnesses, but in that Sense ghosts are similar to us, living humans. 

 
 
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Looking at ghosts (figuratively speaking) I Would say it is a hell of an undertaking to describe their physics. I, by no means, am going to do it in full, because nobody knows all the answers on that subject, yet it might be helpful to discuss some aspects of ghosts in more or less systematic matter. In this entry I would like to touch the Optics of ghosts.

First of all, let’s review how ghosts appear to us ( See Introduction). To say the least, their appearance is ghostly:

In a dim light ghosts often appear as shadows. And, in general, ghosts have a somewhat limited Visibility: people may not see them at all, but cameras do. And so do animals (dogs, cats). Ghosts also can be seen as 2D reflections in mirrors and in 3D in fog or Smoke. Finally, ghosts can appear to us and then disappear within one occurrence, sort of “dissolve' into thin air. What does this means from the standpoint of physics?