The h Bar

12:24 AM

given rest energy of electron $E_e = m_e \cdot c^2$, its compton wavelength $\lambda = \dfrac{\hbar}{m_e\cdot c}$ and fine structure constant $\alpha = \dfrac{e^2}{\hbar\cdot c}$. The associated radii for quantized energy levels for this electron is given by $r_n = \dfrac{n^2\cdot \hbar^2}{m_e\cdot e^2\cdot c^2}$. How would I write $r_n$ in terms of only $n, E_e, \lambda$ and $\alpha$ ?

I reached at $r_n = \dfrac{n^2\cdot \hbar\cdot c}{\alpha^2\cdot E_e}$

not sure what to do with that $\hbar c$ in the numerator

correction: $r_n = \dfrac{n^2\cdot \hbar^2}{m_e\cdot e^2\cdot}$

update: i reached at $r_n = \dfrac{n^2\cdot \lambda}{\alpha}$

is this correct for an electron with potential $V = \dfrac{-e^2}{r}$ ?

Mohammad Areeb Siddiqui

12:51 AM

nvm i calculated quantized energy levels using this $r_n$ and it worked!

David Z

1:43 AM

@MohammadAreebSiddiqui To learn about building quantum computers, you'd probably want to study experimental physics at university, specializing in something like low-temperature atomic physics.

Mohammad Areeb Siddiqui

i'd prolly have to get a double bachelors b/c where i live i can't live off a degree in physics :P

David Z

Sure, that might be an option. Or you could minor in physics, if that's available to you. Or just take some physics classes for fun while you're getting a degree in something else. Or you could move elsewhere.

Or, don't forget, getting a degree in physics doesn't mean getting a job doing physics.

Mohammad Areeb Siddiqui

im currently doing quantum physics from the opencourseware of mit

i took classical mechanics before

its fun doing physics

sadly getting a degree in physics wont get me a good job to get set for my masters

David Z

It sounds like you already have a career plan for yourself which does not involve quantum computing

Mohammad Areeb Siddiqui

2:04 AM

it actually does not, im planning to save money after graduating and getting a job in CS. then ill move to get a degree in physics and start my quantum computing path after that

hideous plan but i have no option

Mohammad Areeb Siddiqui

2:14 AM

Q. A photon collides with a free electron. Explain why the photon cannot be completely absorbed. (havent been taught photoelectric effect or compton scattering)

My answer: as soon as the photon collides and starts to transfer energy, electron gains energy and moves away stopping further transfer of energy from photon. (if true, why didnt photon transfer all energy at once given it is just a packet of energy?)

David Z

Photons do transfer all their energy at once. (At least, best to assume so unless you are getting into some very detailed theoretical research)

Mohammad Areeb Siddiqui

so is it because the electron didn't get the exact amount of energy it needed to liberate or jump to a higher energy state? but this was cause no absorption at all. what causes partial absorption?

David Z

You're asking about a free electron, right?

Do you know what energy states are available to a free electron?

Secret

3:24 AM

@Slereah That looks like the equation that describe predator prey cycles

John Rennie

3:58 AM

@MohammadAreebSiddiqui the interaction has to conserve both momentum and energy. If you work through it you will find this makes it impossible for he photon to be completely absorbed by the electron.

Secret

4:24 AM

@vzn Well that taught me one thing: I will only talk to her face to face

Unlike cyberspace and any fictional places, you cannot block anyone in real life

(not without killing one or the other or more mildly, some kind of protection restriction law thingy)

This is why the best answers to the most difficult questions often came from real life, because reality is such a bitch, its immense presence will ensure anyone will regurgitate the answers to you

(and sometimes, a combination of exploding internal organs, massive stroke, black outs and etc. due to the immense pressure)

(Lol I am joking, nobody will explode when being confronted, otherwise all of us would have died already just by meeting with each other)

which brings me to a strong argument that unlike other people, I actually like real life alot. Real life is the ONLY realm which ghosting and blocking and trolls have no control of

So yeah, if humanity ever figured out how to upload their consciousness, it will be a massive disaster

(NB Putting trolls there just to show reality is brutal but fair, it will not discriminate against blockers and ghosters, but their antithesis trolls as well)

Anonymous

4:48 AM

@MohammadAreebSiddiqui Advertisement time: Quantum Computing SE. Ask your QC questions there. :P

Anonymous

If you're interested in architecture that's good, because currently, we don't have many people interested in that area of QC other than Daniel Sank and agaitaarino. Maybe @Mithrandir24601 too.

SigmaAlpha

Does anyone know where I might be able to find a derivation of Einstein's field equations in the frame like formulation?

vzn

@bolbteppa holy @#%& rethinking my pov on her, she might be just a little )( crazy! check out her numerous music videos, esp luv the mismatched socks lol o_O :P youtube.com/watch?v=m47mJVUJqrw

vzn

5:21 AM

@Secret (as usual, not entirely sure what youre talking about...) ghosting? try caspering... :P dailymail.co.uk/femail/article-5736691/…

Secret

6:00 AM

> Instead of ignoring someone, you’re honest about how you feel, and let them down gently before disappearing from their lives.

> The general consensus on how to Casper someone is saying something nice before blaming your lack of compatibility. For example: “You’re great, but in all honesty I don’t think the spark is there. It’s been great getting to know you though.

That's not so bad. At least there is information here because of the honesty, thus that information can be used to prevent a future caspering to occur again in a new relationship

> Most people are familiar with terms like ghosting (when you casually ignore someone’s existence and messages). But what about ghostbusting, when you force them to reply?

Haha, I am queen of ghostbusting then

In fact that iluminati sounding The Plan is all about mangling the society so much that it ghostbusts reality itself, so that everyone will eventually lost their ability to ghost

> Freeclimbing is what happens when you go on a dangerous fact-finding mission about someone you’ve matched with. First you Google their name, then scale the results without the safety net of an undo button to save you. For even if you unlike their graduation photo from 10 years ago, they still get the notification.

I don't use that for dating (because I have no dates), but I do use that alot on ghostbusting.

In some case, had I had an FBI friend, I will find excuse to tie a ghoster to a crime case so that the FBI will torment him/her until the ghostbust occurs

So yeah, of all that modern dating lingo, ghosting is the worst

and not only I have zero tolerance on ghosting, I have negative tolerance on ghosting, that I will use every and any single laws of physics, social dynamics, screwing up the ecosystem if necessary, screwing up peoples life if necessary, screwng up politics, peace etc. etc. etc., just to ensure the ability for this world to demonstrate the ghosting phenomenon to be erased forever

and that's is the degree of resentment I have on the ghosting phenomenon. If I am Kim Jong Un, I won't hesitate to MAD just to ensure ghosting never exist

(Except Kim won't do that since he is not crazy)

Anonymous

6:47 AM

@Secret Sometimes it may be necessary though...

Secret

That's true, especially when the other partner is a troll. ghosting is one of the most effective antidote to trolls to be honest, I cannot deny that

Anonymous

And sometimes you're just so busy with your life that you don't even remember someone's existence. That happens a lot.

Anonymous

@Secret Not only for trolls, but also for people whom you don't find interesting (speaking from the other perspective here)

Secret

@Blue I actually try to counter that my having a notebook of names and significant events related to them, but yeah, keeping track of 300+ names is not easy

Anonymous

If you're being ghosted the best option is to move on rather than ghost-busting tbh :P

Secret

6:52 AM

@Blue For that, I will often state clearly I am not interested, and then if they persists, I will then ignore. But I usually won't ignore people from the start. That might be just how my morality to demand everyone including myself to be at least accountable works though...

@Blue easier said than done, given my personality trait to require almost everything and every phenomenon to be traceable back to its roots (interestingly, this trait is also what give me my research ability in academia)

Anonymous

@Secret While that is good, the majority of humans are quite different. Ignoring people you don't find interesting is more of an evolutionary trait I guess. I am not commenting on whether it is morally right or wrong.

Secret

Yeah, I don't know how common moral system think of that really

Anonymous

It would be interesting to see how much this phenomenon persists in the animal and insect kingdom.

Secret

7:19 AM

https://www.psychologytoday.com/us/blog/evolution-the-self/201604/the-curse-apathy-sources-and-solutions
Still looking for evolutionary roots

Secret

7:29 AM

0

Q: What is the evolutionary or biological origin of apathy and indifference. Is it uniquely a human thing?

We knew that social apathy is one of the main reasons why changes cannot be brought about easily due to the general disinterest of the public, and has ties with many mental diseases But does the act of indifference and apathy actually has an evolutionary advantage and more curiously, does anima...

nah, google is not helping here, posted a BSE on that now

Anonymous

@Secret Yeah, I looked a bit. Couldn't find much. Upvoted your question. It's quite interesting and I'd like to know the answer too :)

Secret

Yeah, it never come across me to the thought that indifference may be biological, thus this make it interesting intrinsically speaking

esepcially in light on how there are many evolutionary evidence that altruism is a byproduct of selfishness

Mithrandir24601

7:44 AM

@Blue - can I nab you for a moment in the Classical channel?

Secret

10:19 AM

I have edited your post, partly to correct the English, and in particular the misuse of the word disinterest, which means lack of bias from having an interest (financial etc.) in something. I have also changed "We knew" (presumably meant as We know) to "I believe". I believe it is bad practice to make unsupported assertions of this sort, attributing them to others, rather than taking responsibility for them yourself. I personally neither know what you assert, nor do I believe it. — David 56 mins ago

Huh, I thought that apathy resisting change is a well known thing in progressives?

John Rennie

@Secret it's rather pompous but in the interests of getting an answer I'd probably let it go

Secret

Well, I am just curious, no harm is done by David

John Rennie

But I suspect you're looking at this the wrong way.

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