Quantum Mechanics help for a freshman undergrad

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Hey all. I've recently graduated high school and will be entering college this fall. I managed to get my hands on an inexpensive copy of of Griffith's Introduction to Quantum Mechanics and thought I'd jump on the opportunity to teach myself something I have immense interest in. I started reading the first chapter, and quickly found myself overcome by the difficulty of the mathematics involved. I've done my fair share of mathematics - teaching myself the introductions to differential equations and linear algebra. I've already done the equivalent of Calculus I and II. I was wondering simply, should the math be this difficult? In fairness, I haven't really taken a class in differential equations so much as taught myself the basics, and my linear algebra skills are marginal at best. I managed to wade through several of the problems and got correct answers on my own, but some are simply way over my head. Thanks for any help.
 
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Some problems SHOULD be over your head. However your math skills probably aren't up to the level they need to be to really get the most out of the text.
 
I picked Griffiths up as a freshman as well, but only after I had taken a course on linear algebra and ODEs. You will need to supplement Griffiths with a good math methods text, I recommend Arfken. At your level some may recommend Boas, while it is also a good text, Arfken is much better. Arfken is in fact an easy text as well, and any section within the book is self-contained.

I might turn some heads by saying this but you should also get a copy of Sakurai's Modern Quantum Mechanics, which is a standard graduate text. I don't recommend it to learn basic QM from, I only recommend it because the first chapters on formalism and axioms are clearer than any introductory text out there. Also, Griffiths uses old notation and Sakurai is almost exclusively in Dirac notation. Every physics student should be comfortable with BOTH notations.
 
If you can solve 2nd order ODEs you should be able to cope fine with the first 2 chapters. That's basically the only math there (except for a bit of probability in chapter 1). If you're struggling with these chapters I'd suggest leaving it for a bit until you've studdied more on ODEs.
 
Thanks for the help. I've signed up for differential equations my first semester, so I'll be taking that before I delve into Griffith extensively some more.

I was able to follow the first chapter's mathematics, and, as I said, some of the problems I was capable of solving without much difficulty, but I guess following ODEs is very different from being able to apply them with ease.

I'll take a look at Arfken. Thanks for the recommendation.
 
Hi, I had an exam and I completely messed up a problem. Especially one part which was necessary for the rest of the problem. Basically, I have a wormhole metric: $$(ds)^2 = -(dt)^2 + (dr)^2 + (r^2 + b^2)( (d\theta)^2 + sin^2 \theta (d\phi)^2 )$$ Where ##b=1## with an orbit only in the equatorial plane. We also know from the question that the orbit must satisfy this relationship: $$\varepsilon = \frac{1}{2} (\frac{dr}{d\tau})^2 + V_{eff}(r)$$ Ultimately, I was tasked to find the initial...
The value of H equals ## 10^{3}## in natural units, According to : https://en.wikipedia.org/wiki/Natural_units, ## t \sim 10^{-21} sec = 10^{21} Hz ##, and since ## \text{GeV} \sim 10^{24} \text{Hz } ##, ## GeV \sim 10^{24} \times 10^{-21} = 10^3 ## in natural units. So is this conversion correct? Also in the above formula, can I convert H to that natural units , since it’s a constant, while keeping k in Hz ?

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