RE: Something that has been on my mind
November 30, 2015 at 12:42 am
(This post was last modified: November 30, 2015 at 1:00 am by Alex K.)
(November 29, 2015 at 12:25 pm)Redbeard The Pink Wrote:True, I'm not sure what the significance of that is though. An electron-positron pair jointly also has the same property before the annihilation, and quantum mechanically the two cases can't really be sharply distinguished.(November 29, 2015 at 11:50 am)Quantum Wrote: No. For example, an Electron and its antiparticle, a Positron, each have, via their mass, a rest energy of 511 keV. If they meet, they annihilate and the result of this process is two photons with 511 keV each. Energy is not lost.
When Protons and Antiprotons, Neutrons and Antineutrons meet as would be the case with proper Antimatter, much of their rest energy goes into Neutrinos as well, not just photons. This is discussed by the CERN website they created in the wake of the Dan Brown movie "Angels and Demons."
Photons have zero values for most conserved traits, though (charge, mass, etc.). When they're talking about "nothing," in this sense, I get the idea that they mean something that is physically close to nothing, maybe with a few photons whizzing around in it or something. Again, I'm a laymen, not a sophisticated physicist, and I've only been exposed to summaries of this idea.
Krauss' argument about universes from nothing, iirc, is that while the universe contains energy in form of particles and radiation, if one assigns an energy to spacetime curvature to obtain a total conserved quantity (energy content alone is not conserved because of the redshift) one can argue that the sum of the two is zero. This suggests that it could all have sprung from a previous different, simpler zero energy state. He calls that nothing, but one can argue about whether that is truly a sensible notion of nothingness till the cows come home.
The fool hath said in his heart, There is a God. They are corrupt, they have done abominable works, there is none that doeth good.
Psalm 14, KJV revised edition