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Annihilation  matter/antimatter 
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#1
Jul209, 01:31 PM

P: 308

sorry for this elementary question. when an electron (matter) and a positron (anitmatter) collide, they annihilate, releasing high energy photons/gamma rays  correct?
so, when particle pairs are created within the quatum foam, which pop into and out of existence within the planck time period, where does the annihilation energy go? and, antimatter is not the same as a negative energy particle, correct? what is a negative energy particle? thanks. 


#2
Jul209, 02:20 PM

Math
Emeritus
Sci Advisor
Thanks
PF Gold
P: 39,502

My understanding is that what happens is that the energy produced when two particles annihilate in the quantum foam is that it almost immediately goes into the production of two new particles. It is not a "given" that there exist "negative energy particles". I believe that they was originally postulated as "antiparticles" but I don't know what their status is now.



#3
Jul209, 02:24 PM

P: 302

I believe the energy you're talking about is what we refer to is vaccuum energy. The nonzero expectation value of energy in a vaccuum implies that even nothing has energy. If I'm wrong, please correct me.
However, I can tell you that antimatter is not the same as negative energy matter. Antimatter has positive mass, as I found out once :). 


#4
Jul209, 03:34 PM

P: 308

Annihilation  matter/antimatter
well, then where does the "negative energy particle" come from which supposedly accounts for BH evaporation?



#5
Jul209, 04:15 PM

P: 15,319




#6
Jul209, 04:16 PM

P: 4,663

In the bubble diagram (virtual pair production) for photons, the total mass (energy) uncertainty is dE=2m_{0}c^{2} (where m_{0} = electron rest mass.
The Uncertainty Principle allows a dE for a duration dt = h_{bar}/dE. If we write h_{bar} = λ_{bar}·m_{0}c where λ_{bar} is the reduced electron Compton wavelength, then dt = h_{bar}/dE = λ_{bar}/2c, or c dt = λ_{bar}/2 is the length of the bubble = 1/2 reduced electron Compton wavelength = (1/2)·3.86 x 10^{11} cm. Thus the dt is the time it takes for light to travel ~ (1/2 pi) x electron Compton wavelength. α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ ς σ τ υ φ χ ψ ω ± − · × ÷ √ . 


#7
Jul209, 04:30 PM

P: 302

Where's George (Jones)? 


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