/sci/ - Science & Math

I hate all of you.

>>8763068

Sure, we only perceive a fraction of reality as it is but fortunately, we've devised tools to help us see the bigger picture.

Get your metaphysical nonsense out of here.

I'm a physics student,my next exam will be quantum mecchanics, i tried many times to learn it and i can't approach in the right way, so i'm here for search some advice.
I don't have very big problem in understanding concept but i can't apply the theory to exercise, so i'm asking a dumb-proof guide to do quantum exercise.
The main argument are wave fuction and operator, angular momentum,spin , perturbative theory dependent and indipendent from time, and some notions about fine structure and atoms.
Maybe some more powerful physicist can help a quantum newbie.

A doctorate in mathematics or physics?

Hey /sci/, I'm just starting some intro QM and I was told that the probability density function is just the wave function multiplied by it's complex conjugate, ei. [eqn] | \psi_{(x,t)} |^2= \psi_{(x,t)} \cdot \psi_{(x,t)}^* [/eqn]
Now my question for all the math/science guys out there is, what is a complex conjugate? All I really know about it is that wherever you see [math] i [/math] you replace it with [math] -i [/math] but what if the wave function has no imaginary parts? Do I just square it to get the probability density? Is the complex conjugate just the same as the original function?

>>7626000

You little ayyy think the electron or the singularity as a point in a space.

The electron is just a probability density function.

The singularity is just a mathematical object that does not exist.

what's a good book about physics (not a textbook) that i can give to my 15 yr old student.

i thought about giving her relativity and its roots, but it was too much for her.

any recommendations?

Why is hydrogen energy eingenstates stationary states, but have non zero probability density?

didn't we just say they're stationary?

Bawww thread for CERN
http://m.aljazeera.com/story/2014919131524321817

>>6630084
bump

If you were going to get a math/science related tattoo... what would it be?

Why?

Why are we traversing the 4th dimension in one direction?

Okay, so if the inner product of two wave functions is equal to zero, they are orthogonal, that is

<ψ1(x)|ψ2(x)>=0

I get that the |ψ(r)|^2 gives the probability of finding a particle in a certain region in space; if its an electron than that space corresponds to its orbital.

The way i see orthogonality is that the probability density described by wave functions have no overlapping volumes.

But could someone explain it how they understand orthogonality. I would like to explore the meaning of orthogonality in quantum mechanics because i want to have a more intuitive understanding of the subject.

Cheers

Bump.

Amidoinitrite?

I dont have any idea of what this is really but maybe relevant.
Wave function is some of the hardest things to understand I've noticed.

>>4240721

Bingo.

Take a look at this though (we haven't properly looked at the 2nd row transition metals in Uni yet) but:

Y: 4d1 5S2
Zr: 4d2 5S2
Nb: 4d4 5S1

Apparently for a Niobium atom, it's more stable to have 4 electrons in the d subshell, and a half filled s shell, than to have all 5 in a half filled d subshell.

The d orbitals are quite complex though - as you're teching yourself, you should look at the mathematical models from the Schrodinger equation etc which show the spaces where electrons occupy (giving us a 3d model of the orbital.)

S orbitals are spheres; P orbitals are like dumbbells and there are 5 d orbitals shaped like 3 Xs, a + and a crazy thing lol (dZ^2).
Also to learn: Atomic orbitals vs Molecular orbitals (s,p,d and f orbitals are 'atomic' and they overlap to form 'molecular' orbitals (bonds) called sigma, pi etc

If it gets a bit complicated, back up a step. As a chemfag, i'm afraid i have nothing but love for this kind of stuff.

Can somebody explain please what exactly is going on in this explanation? What is the hydrogen atom undergoing, what is being done to it, and how is it reacting?

>>4013891
yes and no

>>3983595

That is not what I meant.

But, Its always been of interest to me. I've come across wave functions recently and realize that I don't have the mathematical credentials to allow me to understand this. However, I feel something quite amazing is being expressed here. If someone could explain this to a relative noob, I would appreciate it. Also, if I were to want to understand this area of mathematics and physics, where is a good place to start? I'm currently learning classical mechanics and (to my dismay) calculus.

Also just something you might be interested in, there are what the wavefunctions look like for hydrogen. You may notice that they, at first, don't appear to be what you thought of as waves, but first appearances are deceiving. We know these are the wavefunctions (in the nonrelativistic approximation) because of the [time-independent] Schrodinger equation, which gives accurate predictions for the energy levels of hydrogen.

Morning, /sci/entists!

I'm trying to work out the region of space in which an electron in Hydrogen in the ground state would not be able to enter if it were a classical particle of the same energy.

Clearly, the inequality will be

Total Energy > Potential Energy

with the Potential Energy being <span class="math">\frac{-e^2}{4 \pi \epsilon_0 r}[/spoiler], but I can't convince myself of how to express the Total Energy in a form that I can both see where it came from and which lends itself to the inequality cancelling out correctly.

Any suggestions would be appreciated. :)