query: Why electron-positron annihilation releases two gamma photons?
positive_passages.docid: 28165
positive_passages.text: Why can't a single photon produce an electron-positron pair?
negative_passages.docid: 14203
negative_passages.text: Finding the creation/annihilation operators
negative_passages.docid: 152586
negative_passages.text: Does a photon have an amplitude?
negative_passages.docid: 41889
negative_passages.text: Why is the $S_{z} =0$ state forbidden for photons?
negative_passages.docid: 82218
negative_passages.text: Do we really not know why atoms 'decide' to produce a photon?
negative_passages.docid: 85984
negative_passages.text: How come $\frac{\partial(\partial_{\beta}A_{\gamma})}{\partial(\partial_{\mu}A_{\nu})} = g_{\beta\mu}g_{\gamma\nu}$?
negative_passages.docid: 3909
negative_passages.text: Does $E = mc^2$ apply to photons?
negative_passages.docid: 98458
negative_passages.text: Radiation emission and absorption
negative_passages.docid: 37533
negative_passages.text: Emission of EM radiation from an electron
negative_passages.docid: 69983
negative_passages.text: Photon energy - momentum in matter
negative_passages.docid: 150813
negative_passages.text: Why does a photon colliding with an atomic nucleus cause pair production?
negative_passages.docid: 109780
negative_passages.text: In the double-slit experiment of electrons (observed by photons), is it correct to say the collapse is caused by the momentum of the photons?
negative_passages.docid: 17787
negative_passages.text: Photoelectric Effect, Why can't two quanta interact with an electron at the same time?
negative_passages.docid: 27803
negative_passages.text: Why are photoelectrons emitted in the direction of incident photons?
negative_passages.docid: 94616
negative_passages.text: How do gamma distributions add and what would that model?
negative_passages.docid: 89344
negative_passages.text: Radioactivity and quantum superpositions
negative_passages.docid: 125081
negative_passages.text: What is the reasoning that leads one to postulate this second form for the relativistic particle action?