Just in case it wasn’t clear you can’t measure anything other than “100%” up or down spin. The quantum state of it being 50/50 is described by 1/sqrt{2} times the up and down vector, when you measure it you have a probability of getting either result calculated by the square of the absolute (||psi||^2) that way you avoid getting a complex probability.
btw I was too scared to try in case it doesn’t but can I use LaTeX in Lemmy comments? $\psi$
Edit: No LaTeX doesn’t seem to work and btw I didn’t study this so it might be taught differently at uni. This was explained to me in/for the context of quantum computing.
True! Thanks for the clarification, it’s been a while since i played with the maths of quantum physics!
After you measure a spin as 100% up, the state will be close to that for a while, si the next measurement has higher chance of being up, with this probability slowly decreasing with time.
I think that assuming the particle has no (extra?) energy it’s state does stay the same. That is of course not possible in real life though but the <20 millikelvin in some quantum computers get pretty close.
Also I think nobody says they measure it as 0/100% up, They just say up or down in my limited experience.
Does anyone have any good resources on quantum mechanics? (Most of my information comes from a few professors)
There’s some useful stuff on chem libretexts (I think that’s what it’s called) for simple wave functions, but it doesn’t seem perfect.
Just in case it wasn’t clear you can’t measure anything other than “100%” up or down spin. The quantum state of it being 50/50 is described by 1/sqrt{2} times the up and down vector, when you measure it you have a probability of getting either result calculated by the square of the absolute (||psi||^2) that way you avoid getting a complex probability.
btw I was too scared to try in case it doesn’t but can I use LaTeX in Lemmy comments? $\psi$ Edit: No LaTeX doesn’t seem to work and btw I didn’t study this so it might be taught differently at uni. This was explained to me in/for the context of quantum computing.
True! Thanks for the clarification, it’s been a while since i played with the maths of quantum physics!
After you measure a spin as 100% up, the state will be close to that for a while, si the next measurement has higher chance of being up, with this probability slowly decreasing with time.
I think that assuming the particle has no (extra?) energy it’s state does stay the same. That is of course not possible in real life though but the <20 millikelvin in some quantum computers get pretty close.
Also I think nobody says they measure it as 0/100% up, They just say up or down in my limited experience.
Does anyone have any good resources on quantum mechanics? (Most of my information comes from a few professors) There’s some useful stuff on chem libretexts (I think that’s what it’s called) for simple wave functions, but it doesn’t seem perfect.
I have old college textbooks in my library, Cohen-Tannoudji. I’m not sure about online resources though…