Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: clueless on 07/05/2014 17:18:58

Title: Are atoms miniature cloaking devices?
Post by: clueless on 07/05/2014 17:18:58
Atoms are 99.999999999% empty space which means all the matter that makes up the human race could fit in a single sugar cube. Is it at all possible that 99.999999999% of an atom is actually a non-observable physical body with perfect camouflage? [:I] Could that be the reason why we have mass when we stand on the scale? Or are we all holograms? 

Making an opaque material transparent might seem like magic to humans. But for well over a decade, human physicists have been able to do just that in atomic gases using the phenomenon of electromagnetically induced transparency (EIT).
Title: Re: Cloaking device (a long shot)
Post by: chiralSPO on 07/05/2014 17:30:56
We have very, very accurate measurements of the mass of the atomic nuclei, and they account for almost all of the mass of the atom (>99.95%). As you pointed out, the volume of the nucleus is extremely tiny compared to the volume of an atom, but that just means that the nucleus is extremely dense. The remaining mass is from the electrons. If you want to say that the electron cloud is this physical body that takes of the rest of the space, I suppose that is debatable, but A) this body has very little mass; and B) the electrons are the part of the atom that we can observe with light.
Title: Re: Cloaking device (a long shot)
Post by: CliffordK on 07/05/2014 18:29:35
Hmmm,
Interesting thought.

Say you take a simple carbon compound such as graphite.  It gives you a nice rich black color and absorbs most light. 

Change the molecular structure of the same atoms to make diamond, and it is now transparent (one would note, that even in "transparent", the speed of light varies, as well as surface interactions refracting the light).  One would also note that being transparent may be for certain EM wavelengths, but not for others, especially if one considers IR, Visible, UV, and various radio waves.

For the most part, absorption, reflection, or transparency is an interaction of light with the electrons, and perhaps electron resonance patterns.  So, change the electron resonance, and you may change the color spectrum.  Unfortunately that may be easier said than done, especially when dealing with a myriad of different compounds. 

Liquid crystals will change colors (crystal structure) with temperature or electricity.  I presume substances could also be changed within a magnetic field.  But, alas, the human body, for example, may not react well to the forces required to make it transparent, or invisible.