If anyone could share any link for the calculations behind this collision, that would really help, because even though energy is conserved here I guess we can apply normal conservation of energy formulae here to get m(of e-)v=m(of e+) v , ?? Also, for that split second, would the electron be moving with velocity c? Then would momentum go from h/llambda to m(of electron)c? Also if you could explain, what exactly is momentum , because we donβt use mv for a photon, why is that? Someone told me mv is just an approximation, then whatβs the read deal? Thank you so much if you answer any of this.
When a negatively charged electron and a positively charged positron collide they are annihilated and produce two photons. "Since both the electron and positron are defined entirely by information encoded in cell states, their collision and annihilation is simply the processing of information" (Gallimore, Andrew).
We can apply this principle to the whole universe and our purpose within it. The interplay between positive and negative in our inner and outer state is the catalyst that perpetually informs and defines us.
The meaning of all existence is to engage in the co-creation of reality as exploration of self in the duality of relativity through what we perceive as positive and negative experiences. We label these things good and bad, up and down, black and white, love and hate, birth and death, us and them, physical and metaphysical, God and man.
As we play upon this infinite field of probability we annihilate these positive (positron) and negative (electron) dualities within us one by one revealing an endless stream of information, continuously updating details of increasing complexity about who we are within this relative expression while simultaneously shedding Light (photons) upon the entirety of creation. πΌππ
Both pairs have opposite charges why does they need to have the same mass to annihilate?
I know as well PET scanning relies on the detection of these two 511Kev photons. If this is the case why can't the e- or e+ have greater energy surely this would just lead to the two photons having a greater kinetic energy without violating any conservation laws so far as I can tell.
Hello During the annihilation of an electron and a positron via a virtual photon is there equal probability of creation of each possible particle-antiparticle pair ? (if the total energy is far of any resonance). For example for a collision at 200 MeV, 20% electron+positron, 20% muon+antimuon, 20% red pi^0, 20% green pi^0 and 20% blue pi^0 ?
The parity of the electron and positron are opposite so their combined parity is negative.
The resulting two photons both have negative parity so their combined parity should be positive.
So how is this reaction possible?
Edit: Thanks for all the replies and discussion!
I read today that Positron Emission Tomography works by splitting positrons off of fluorodeoxyglucose, where they annihilate with free electrons. The resulting radiation is scanned by the PET machine to produce a functional map of the body part.
I had thought that matter-antimatter annihilations produced extremely high-energy explosions. Is there a difference between positron-electron annihilations and hydrogen-antihydrogen annihilations? Why isn't the radiation dangerous, either?
Hi, So I'm doing some very basic particle physics at the end of my irish high school physics course, and we were doing pair annihilation of electrons & positrons. Essentially my question is why there is an surplus of electrons in the universe? If positrons were formed at the same as electrons how are still electrons? Or by what other process can electrons be formed (splitting neutrons?)?
Thanks very much for reading.
Additionally, would the energy released from annihilation be greater between two particles move a distance further from the surface of earth compared to annihilation of the same particles at the surface of earth, where gravitational potential energy is zero/less.
According to Through the Wormhole, it is. According to my Astronomy Professor, is it not, and this video is either not telling the whole story of the experiment, or is completely fabricated "for TV" as the annihilation causes energy to be released in gamma ray form of 511 keV, whereas visible light is only 1 to 3 eV.
So, reddit, how is the annihilation as shown in the Through the Wormhole episode possible?
PS - I hope there is an explanation; if this turns out to be completely false it's going to crush my soul - I love that damn show!
For instance, they are of opposite charges (as a proton and electron in a hydrogen atom), it sounds plausible that they capture each others and form a stable positronium atom.
From my understanding, they are both considered point particles with zero-length radii. What is the probability of two zero-lengthed points to touch?
The genius of Tenet, to me, is that the concept of inversion (and reversion) is a macroscopic analogy of two symmetric quantum mechanical interactions known as pair-annihilation and pair-production. Nolan used concepts derived from quantum mechanics to craft a really clever and original sci-fi/action/spy-thriller, which to me is a really unique accomplishment. However, I think Nolan should've focused on these ideas, popularized by Feynman and Wheeler, rather than the idea of "reversing entropy". The explanation makes so much more sense to me.
For those interested in the link between inversion and Feynman and Wheeler's absorber theory, watch this video: https://www.youtube.com/watch?v=rst9EcF9ryk and also this one: https://www.youtube.com/watch?v=9dqtW9MslFk
You can see where Nolan got his ideas for his concept of time-inversion. You can think of the turnstiles as "deflecting" particles backwards or forwards in time by changing their charge and parity (mirror-reflection). To an external observer, inversion appears as "annihilation" where both forward-time and backward-time versions of a particle (or electron and proton, if you will) come into contact and disappear, releasing energy (a photon) in the process; the turnstile can be thought of as carrying out a "controlled" annihilation of whatever enters the red side (inversion). This can be seen in the scene where Sator first inverts himself. He appears to simply disappear; but as Ive's points out, he went into the past. If forward Sator is a electron, inversion is deflecting him backwards in time by turning him into an positron, which to our eyes looks like a positron and electron meeting and disappearing.
Rerversion is the opposite of this interaction, wherein an electron and positron spontaneously manifest from energy (a photon). This can also be interpreted as a positron (time-reversed electron) being deflected forward in time by having its charge and parity reversed (turned back into an electron). The turnstile probably works this way to revert whatever enters the blue-side. This can be seen in the movie when inverted-protagonist reverts himself; from the external observers (Protagonist and Neil during first visit to Oslo) it appears like two identical Protagonists clad in black armour spontaneously emerge from the turnstiles.
Ok so my current understanding of the formation of electrons at the big bang ish is from to colliding high energy gamma rays from black body radiation turning into a positron-electron pair to keep net charge 0 but as they are antimatter of each other so why don't they annihilate each other?
I understand that two photons have to be created if the electron and positron collide head-on. In that case the total linear momentum is equal to 0 before the collision and to conserve this, two photons going in opposite directions have to be formed to keep the linear momentum equal to zero. But what if the electron and positron collide at an angle that's not 180 degrees, why can't one photon with more momentum be created?
Does the energy come only from the mass of the colliding particles or does it include the kinetic energy of the particle-anti particle pair as well? If there was enough energy, could it materialize into a more massive pair
I'm a bit confused here. Normally virtual particles are used as mathematical "tricks" but in this case they create real matter? Can someone explain?
My only guess would be that electrons need to be accelerated to much higher velocities, which may have been limited by the radius of CERN at the time via cyclotronic radiation.
EDIT: I should add that I am asking for the sake of studying the Higgs and other W/Z boson interactions. Obviously e-e+ can't be used to study quark interactions.
how does conservation of angular momentum (in particular, intrinsic angular momentum) come into play in electron-positron annihilation?
does the relative spin of the two particles simply become the relative polarization of the two photons?
Trying to get a mental picture of how these things work, I know electrons release photons when they are shaken (accelerated in any way), but if two particles with opposite charge are moving passed each other without any acceleration, and I assume without releasing any photons which is what mediates the electric field, would they attract each other or be indifferent?
