The h Bar

9:00 PM

@Mithrandir24601 Let me think for a second there is a simpler way I think.

Anonymous

@Mithrandir24601 Well, essentially all the materials I studied in the last two years can be boiled down to 10 medium sized books easily. The major problem during my prep was that the exam I was preparing for has no standard study material or prescribed books...so I had to hunt for material from here and there...

Anonymous

It was like combinatorics from book A is good but calculus from book A is terrible. But that's better in book B. And so on...

Mithrandir24601

Mine are just from lots of different subjects - to bore everyone: quantum info/computation (best value textbook I ever bought at a mere £7 :) ), quantum optics, quantum mechanics (1 grad level, 1 undergrad level), theoretical computer science, algorithms, (classical) information theory, maths for physicists and Dirac's general relativity book (smallest textbook I own). Although all of this is from the last 5 years to be fair

Anonymous

@Mithrandir24601 I see. Nice :) BTW I checked your profile just now and saw you are a mathematical physics phd student. Was your UG degree in Physics too?

Mithrandir24601

@blue My undergrad was Physics and Computer Science

But this was really due to the fact that I did some CS in first year, then physics for the rest of the degree

Jaime Gallego

9:15 PM

@Mithrandir24601 I bought this weird commie analysis book a while ago

It says CCCP on the cover

Anonymous

@Mithrandir24601 Oh wow! Nice :) I will have to go through my UG college admission procedure later this month. I'm planning to take up a core engineering degree. Is it possible to pursue theoretical physics or mathematical physics after a core engineering degree? Any ideas? (Since I'm quite interested in Physics but probably won't be allowed to get a pure physics UG degree due to some reasons...especially financial reasons)

John Doe

@Mithrandir24601 Let $X$ be the event that you choose a red ball first. Thus $P(X) = \frac{3}{4}$ this follows since the probability you choose the '2-red bag' is $1/2$ and probability that you choose red from the bag is $1$ and the probability for choosing the 'red-blue bag' is $1/2$ with probability of choosing red $1/2$. Let $Y$ be the event that the second ball you choose from the same bag is red. $Y$ happens only when you choose the '2-red bag' hence $Pr(Y) = 1/2$.

The event $X \cap Y$ happens if and only if $Y$ happens, hence using conditional probability, the probability of choosing a second red from the bag is $$P(Y|X) = P(X \cap Y)/P(X) = 2/3$$ hence the probability of choosing a second blue is $1 - 2/3 = 1/3$.

Mithrandir24601

@blue Also, the mathematical physics was just for the MSc, but I'm currently doing a project in theoretical physics which is close enough, so I'll give you that one for a few months anyway :P

Wow, I'm popular at the minute...

John Doe

This might not be the smoothest way of doing it but I just want it to be right for now :)

Mithrandir24601

@JaimeGallego 'Союз Советских Социалистических Республик'? (from Wiki - essentially Russian for Soviet Union)

Jaime Gallego

9:20 PM

Mithrandir24601

@blue I'm not the best person to answer that... Although engineering to physics, I'd say yes. Engineering to theoretical physics is perhaps technically possible, but I'd say it's extremely unlikely, although if you're able to take physics modules, then it could be possible, I suppose? (I wouldn't be surprised if this varies by country)

Anonymous

@Mithrandir24601 Yeah, I suppose it varies w.r.t country. Although the engineering college I'm expecting to join will allow me to take elective courses in QM, Relativity and a minor in Physics. I perhaps need to discuss this with some seniors who have already studied in those colleges. Anyway, thanks a lot for your inputs :)

Mithrandir24601

@JohnDoe Seems to make sense...

John Doe

@Mithrandir24601 Great thanks man

Mithrandir24601

(certainly conditional probabilities is the way I'd go about thinking about such things, not that that's worth much, if anything :P )

heather

9:26 PM

'ello (again) question:

Anonymous

@JohnDoe For these type of probability problems the fastest way is to draw tree diagrams. It avoids all the mathematical jargon. :)

Sanya

@blue honestly said, you won't need the physics minor or the QM courses; you'll need math courses - that is the point where at least in my experience most engineering faculties do not sufficiently prepare you for theoretical/mathematical physics and you'll find yourself disappointed at some point because you do not have the mathematical prerequisites to go on

heather

in the book "The Road to Reality" by Penrose, he says you can get from a conformal to a projective representation of hyperbolic geometry by an expansion radially out from the center by an amount given by $\frac{2R^2}{R^2+r_c^2}$

isn't that just $\frac{2}{r_c^2}$

ACuriousMind

@heather nope

heather

i'm pretty tired, so that probably is a big "what the heck are you doing" moment, but why not?

Mithrandir24601

9:29 PM

@blue That seems a bit more promising... Yeah, talking to people there (and the lecturers!) is the way to go

ACuriousMind

@heather Why would it be?

Anonymous

@Sanya Oh oh, I see. So you suggest me to take more Mathematics elective courses than Physics courses? Would a minor in mathematics be more beneficial then?

John Doe

@blue Yeah I think there is a simpler way to the problem using Bayes theorem maybe. Not sure about tree diagrams never used them.

heather

@ACuriousMind $R^2/R^2$ cancels

ACuriousMind

@heather Fractions don't work that way

Bernardo Meurer

9:30 PM

@heather Fractions don't work

heather

::yells at brain::

ACuriousMind

If you want to "cancel" the $R^2$, you get $\frac{2}{1+(r_c/R)^2}$

heather

@ACuriousMind i'm almost certain I've canceled in fractions before...

@ACuriousMind oh duh ::smacks brain again::

Bernardo Meurer

@heather Yes, but you have addition on there,not multiplication

Anonymous

I mean I have a choice of choosing a minor like CS or Maths or Physics along with core engineering. So you suggest that a mathematics minor is more beneficial if I am inclined towards higher studies in theoretical physics? @Sanya

Bernardo Meurer

9:31 PM

if it was $$\frac{2R^2}{R^2 \cdot r_c^2}$$ you could do what you said

Sanya

@blue I can of course only speak from my experience/the university programmes I have seen

Mithrandir24601

@blue Why are you inclined towards higher studies in theoretical physics?

heather

@Bernardo yeah. thanks =)

Bernardo Meurer

@heather But since it's $+$ and not $\times$ you gotta work more :P

Sanya

but a normal master degree in physics does not have enough math lectures by default for a decent study of theoretical physics

Bernardo Meurer

9:32 PM

No worries, this is pretty much all the maths I know

Sanya

which can already be pretty frustrating while doing physics

heather

thank you, hbar, for putting up with my stupidity =) (with especial thanks to Bernardo, Daniel, and ACM)

Mithrandir24601

@Sanya I'm not sure whether or not I agree with this...

Sanya

and engineering is usually more on the calculating and less on the real core math side with proofs

Bernardo Meurer

@heather Ah, forgot to tell you, I passed Computer Architecture

heather

9:33 PM

@blue where are you located (if comfortable saying)?

Sanya

so I think you'll find yourself having a need for more math teaching

Bernardo Meurer

SUCK IT UNIVERSITY

heather

@Bernardo yeah!! =D good job!!

Avantgarde

You don't need to take exclusively math courses when doing physics. They teach you the math within the physics courses

Anonymous

@Mithrandir24601 The reason being I really enjoy theoretical physics topics (like QM, QFT, Relativity...they are so exciting!). But in my country a physics undergraduate is a sure-shot way of being unemployed and in-debt by the time one is 23-24 years old. A core engineering degree is safer choice in monetary terms...so that I can fund my own higher studies.

Avantgarde

9:34 PM

You can, but it's not necessary

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