/sci/ - Science & Math

[Anonymous No.11252027]

How does the change of state of an electron produce a photon?
What are there other ways to produce photons?

[Anonymous No.11252040]

I remember something about a lightbulb still emitting light when it's turned off because of the electrons being demoted. It'd be nice if someone could explain it again because i dont remember reallt well.

[Anonymous No.11252142]

>>11252027
>>11252040
Electrons require energy to be promoted from ground state to excited state.
E=hv, that energy is given off as light.

[Anonymous No.11252286]

>>11252027
Attach a rope to something in front of you.
Hold the other end in your hand, keeping the rope tight.

Nothing is happening, right? Now quickly hold your end of the rope up. You'll see a wave forming, that travels towards the fixed end.

[Anonymous No.11252313]

>>11252027
>What are there other ways to produce photons?
Electron/hole radiative recombination
Matter - antimatter annihilation

[Anonymous No.11253204]

>>11252313
whats the mechanism which produces the photon? how do the electrons and positrons disappear and how does that result in the appearance of the gamma ray photons?

[Anonymous No.11253309]

>>11253204
This is the electroweak interaction, of which I don't know much. We do know that all properties are conserved. In annihilation, charges sum to 0, I think spin sums to 0, and the rest mass is converted into energy according to the mass-energy equivalency. "How" it happens is explored in electroweak force, but you'll eventually bump into places where we lack knowledge.

[Anonymous No.11254333]

>>11253309
can you turn gamma ray photons back into electrons and positrons?

[Hoaxfag No.11254432]

>>11252027
The electron is creating a resonant standing wave around the atom, called a "probability" cloud, if you energise the atom, for instance heating the atom with a flame, this causes the electrons to jump into higher energy bands, electrons are negatively charged so they interact with background cosmic radiation (electromagnetic fields) and cause perturbations or "ripples" in this electromagnetic "ocean"
This waveform travelling through the medium is what we perceive as light,it's a wave-packet.

[Anonymous No.11254454]

>>11254333
Yes, by the inverse process of annihilation, matter creation. In fact, the theory favors the creation of matter-antimatter pairs in equal parts, but cosmological observations regarding baryon assymetry seem to suggest there may be photon-photon interactions where the results aren't necessarily 50/50 on the anti/matter.
We don't know what causes baryon assymetry, nor any of the other broken symmetries in Nature (time translation symmetry, chiral anomalies and CP violations).

[Anonymous No.11254457]

There's nothing quantum about this. When you change the shape of a charge distribution abruptly (perhaps even by accelerating a single electron), you produce radiation.

[Hoaxfag No.11254540]

>>11254457
Hey man, could you please expand on this? Do you mean like as a possible interpretation of the photoelectric effect?

[Anonymous No.11254559]

>>11254540
Sure. The Maxwell equations describe the motion of charges and the electromagnetic fields they produce
pic related, [math]\rho[\math] is charge density, [math]\textbf{j}[\math] is current density (bold means vector) and E and B stand for the electric and magnetic fields (vectors). The triangles are derivatives, taken in a particular way. basically, this is a set of differential equations, and the interpretation is that charges and currents (what happens when you move a charge) create fields that extend over large distances and allow charge distributions to influence each other. Basically one charge or current creates a force on another charge or current when if they're not physically in the same location.

Solving these equations is quite difficult. Many of the known solutions are in the textbook I posted earlier. In particular, when a charge is accelerated, it generates a change in the electric and magnetic fields surrounding it. This change, or disturbance, propagates away from the location of the charge that was accelerated at the speed of light, until it can influence other charges some distance away. That's what we call radiation.

The photoelectric effect is what happens when one of these disturbances (actually it's a wave) reaches a material that has electrons in it. If the wave carries enough energy, it can dislodge an electron from the material it is chemically bound to. The amount of energy required to do this is called the work function of the material. Any excess energy of the wave can be absorbed by the electron and turned into it's kinetic energy of motion: this means it will be ejected at varying speeds.

What you probably have heard is that this has something to do with quantum mechanics. Not necessarily. The quantum part of this happens when you vary the intensity of the wave source. Naively, the intensity of the source is proportional to the energy of the waves incident on the material.

...continued...

[Anonymous No.11254566]

>>11254559
You would expect a more intense radiation source to eject electrons from the material at greater velocities. In fact this does not happen: more electrons are ejected, but they are as energetic as before. Only by varying the frequency of the radiation source can you give the electrons greater velocity once the work function is overcome.

The interpretation, which is consistent with every experiment done since, is that the intensity of a radiation source is proportional to the number of photons, and the energy of those photons is fixed. If in one event, an electron only has time to absorb one photon's worth of energy before being ejected from the material, then it makes sense that having more photons does not make the electron have a greater energy after it has exited. But there are more photons when the radiation is more intense, so more electrons can be ejected from the material by absorbing a single one. The energy they get once ejected is just the frequency of the photon (times a constant called Planck's constant), minus the work function.

But the process of absorbing and emitting this radiation is one completely consistent with classical physics. No quantum mechanics is needed to explain that effect.

[Anonymous No.11254575]

>>11254566
A small caveat:
When you increase the intensity of a radiation source, you are also likely changing the distribution of frequencies that it emits. A slightly brighter lamp, for example, probably has more high-frequency photons than a cooler lamp does. This means the ejected electrons will be slightly more energetic on average. However, this is a secondary effect and doubling the energy output of a lamp will not double the energy deposited into any single electron that escapes the material.

[Anonymous No.11254579]

>>11254559
>actually it's a wave)
huh?

[Anonymous No.11254580]

>>11254579
If you take the Maxwell equations and set [math]\rho= \tectbf{j} = 0[/math], you get equations for just E and B. These equations can be manipulated algebraically to show that the components of E and B satisfy what is known as the wave equation. So one possible behavior for the electric and magnetic fields is to act as a wave when there are no nearby charges.

[Anonymous No.11254582]

>>11254580
[math]\rho= \textbf{j} = 0[/math]*

[Anonymous No.11254590]

>>11254579
Look, if you really want to learn basic E&M, watch some lectures online. There's some famous ones by Walter Lewin:
https://www.youtube.com/watch?v=x1-SibwIPM4&list=PLyQSN7X0ro2314mKyUiOILaOC2hk6Pc3j&index=2

And more modern (from a class on waves and oscillations):
https://www.youtube.com/watch?v=8kcvyoHsXrw

[Hoaxfag No.11254635]

>>11254559
Man you have been so helpful in a project I have been working on for such a long time. If you only knew lol.
I will be forever in your debt.
Flawless work.

[Anonymous No.11256008]

so is an electron some kind of trapped standing wave made out of a gamma ray?

[Anonymous No.11256024]

>>11256008
no.

[Anonymous No.11256030]

>>11256024
prove me wrong

[Anonymous No.11256042]

>>11256030
You proved yourself wrong when you used two words that aren't synonyms to refer to the same thing.

[Anonymous No.11256054]

>>11256008
According to The Standard Model the photon field exists parallel to the electron field with a bunch of other fields. I won't spend more time because this thread will be gone tomorrow and your basic questions back again.

[Anonymous No.11256062]

>>11256008
Here, free knowledge from a verified professional:
https://www.youtube.com/watch?v=zNVQfWC_evg

[Anonymous No.11256070]

>>11256054
I'd be careful about using words like "parallel" in this context. It can be misinterpreted very easily. Then we get schizo threads about how Euclid's 5th axiom proves the speed of light changes over time, or something to that effect.

[Anonymous No.11256183]

>>11256042
no i didn't

[Anonymous No.11256213]

>>11252027
A photon which has acquired more spin levels becomes like a hungry, hungry hippo. The outer spins begin to act like a chomping mouth. The photon with more outer spins can consume smaller photons and trap them inside itself. This eating action causes an increase in density and eventually the photon slows and becomes an electron. The charge emitted by the electron is the consumed photons slipping back out.

[Anonymous No.11256500]

>>11256213
Thanks I think I see how it works in general now. I hope someday I can learn as much physics as you so I can learn the details

[Anonymous No.11256813]

>>11256500
>>11256213
this is wrong though...

[Anonymous No.11258046]

>>11256813
it isn't, electrons are made out of gamma rays

[Anonymous No.11258202]

>>11252027
Which school uniform is this supposed to be?

[Anonymous No.11258461]

>>11258202

[Anonymous No.11258585]

>>11254575
You should read Miles Mathis. He shows that everything is classical down to the photonic level.

[Anonymous No.11258587]

>>11256813
It refers to Miles Mathis' theory.

[Anonymous No.11258681]

>>11258046
false.
>>11258585
>the photonic level
That may sound like official science language to you, but I can assure you it is just nonsense.
>everything is classical
also false

[Anonymous No.11259643]

>>11258681
>I can assure you it is just nonsense
You don't know what/who you're talking about. You have a very closed mind.