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    Girls in physics?

    If you're wondering about a specific college, why don't you just look at their website? Most departments have a grad student directory. I'm not a physics grad student, but as a physics undergrad my graduating class and the class below us was pretty close to gender balanced.
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    Does school get worse towards the end?

    I double majored in math and physics. I found the earlier classes more difficult than the latter. The early classes are usually fast, nonrigorous, vague, and your first introduction to many of the ideas of math/physics. In the latter classes you move slower and the discussion is much more...
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    Courses What additional math course should I take?

    Nope; just mine. :biggrin:
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    Physical significance of the laplacian operator?

    One way to think about the Laplacian of a function is that it is a multi-dimensional version of concavity. In the 1-d case it is just the second derivative. Think about the wave equation for a string- this states the vertical acceleration of a point on the string is proportional to the...
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    Courses What additional math course should I take?

    My suggestion is MATH 4355: Mathematics of Signal Representation. Why? Because I think it will pack the most punch for the money. The idea of a signal is incredibly useful and unifying, and you don't really have go into full rigor to understand things conceptually. I was lucky to learn these...
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    Criminal record and academic career?

    My experience has been that it in no way affects your chances of getting into a grad school. I got a DUI when I was 20. Last year I applied to nine graduate schools (for math), and of those, only one required me to list such information. In that one case I had to write a short explanation...
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    The best way to prepare for real analysis

    I love seeing threads like these, because they remind me that even within something as specialized as mathematics we all have our differences. I'm a grad student and honestly I have a hell of a time with algebra, topology, and number theory, but analysis comes easily. Maybe it is just the...
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    Do I really like physics? is this normal?

    When I encountered high school physics I was not interested much... it, along with math, seemed pretty uninteresting and useless. I was practical so I went to college as as engineer, but I eventually realized that the things that mattered were essentially physics and math. I then became...
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    Field in physics vs math

    Wow, I appreciate the sources Chris! The historical development of the terminology (which in my experience often includes insights) is not something that is commonly taught. I'll keep that information in mind for (1) my own studies and (2) when I teach the subject.
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    Field in physics vs math

    Replies to questions like this always run the risk of going into some sort of pseudophilosophical debate, but what the hell, sometimes they provide some insight. The vector/tensor field seems natural enough... "field" typically refers to something spatial like that... or you could say a vector...
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    Field in physics vs math

    It has nothing to do with physics vs. math. The two different entities of a vector (or tensor) field and an algebraic field were assigned the same name. Both entities occur in physics and math.
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    Algebraic Topology Question

    Once you see why this is true you're going to kick yourself because it is quite simple. Here's the definition of partition into slices: partition into slices = partition into disjoint open subsets such that the restriction of p to each open subset is a homeomorphism
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    Undergrad in 6 years; [First] Impressions?

    My impression: If someone is such that they are impacted moreso by the duration it took you to get the degree then they are by your accomplishments along the way and your potential for the future, then it is likely they will not be in any position of authority to determine your job prospects...
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    Programs What sort of math classes should be taken for quantum theory/physics major?

    Having somewhat recently scaled this hill myself, I'd say it's most important to understand the ideas in linear algebra and how they apply to differential equations. Also, you will want to know the very basic ideas of probability. I'd list off the key concepts to focus on (in this order) as...
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    Two question on analysis

    What you should do with a problem like this is just write down the logical structure that you need to prove the result and look at the definitions of the entities involved. What I mean is this: 1) Show (An converges) implies (Bn converges). The symmetry in the assumptions then gives you the...
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    Countable But Not Second Countable Topological Space

    Thanks! I own that book so I'll be having a look pretty soon.
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    Countable But Not Second Countable Topological Space

    I'm wondering if someone can furnish me with either an example of a topological space that is countable (cardinality) but not second countable or a proof that countable implies second countable. Thanks.
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    Injective function proof

    Am I reading this incorrectly?
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    Injective function proof

    HallsofIvy, I'm not sure what you mean. I showed f^{-1}(f(A_0)) \subset A_0 which is the other half of the equality waht was asking for.
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    Injective function proof

    If x is not in A, then f(x) is not in f(A) (injectivity) so x is not in f^-1(f(A))
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    Programs I want to lern EE, but can not major in it.

    When I first got an internship, it was after my second year in school and the only technical classes I had up to that point were intro mechanics, intro e&m, calc 1-3, intro linear algebra and intro ODEs. Anything else I needed I learned there. Many internships are designed to be an...
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    Programs I want to lern EE, but can not major in it.

    My recommendation is that first and foremost you MUST master basic linear circuit analysis. Beyond that, IMO if you have a good understanding of linear systems and signal processing and know how to work with some sort of field (EM, sound, fluids, etc) you probably can fill in the blanks as...
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    Schools  did not understand Calculus until Grad School

    How is this even possible? When the integral is first introduced one knows the integral of a function is a number (area under curve) and the antiderivative of a function is a function.
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    Online calculus of variations resource

    It's not an online source, but it's dirt cheap: https://www.amazon.com/dp/0486414485/?tag=pfamazon01-20 This book is great- it really only requires a little bit of experience with analysis, the approach is very motivated and clear, and for problems it has both proofs and computation. The...
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    Extending maps defined on dense sets

    First of all, what kind of space are we working in? For X and Y metric spaces, here's what I'm thinking: If the function f is uniformly continuous, it sends Cauchy sequences to Cauchy sequences, so if we select a point x in X and find a sequence in A converging to x, that sequence is Cauchy...
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    To be a mathematician or a physicist?

    I strongly agree with those who say to do both as an undergrad; here are a few reasons why: - There is significant overlap in coursework so it is not that much extra work. Even if it takes you an extra year or a couple summers, I think it is well worth it. - Doing the math makes you better...
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    Programs Typical four-year schedule of a math major

    I'm a double in math/physics, so this may vary from what a strict math major would take, but oh well, these are my last two years. The only junior/senior math courses I took before this time were Cryptography, PDEs, Integral Transforms, and Complex Variables. My first years were occupied with...
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    Mass,Spring, Damper vs Capacitor, Indcutor, Resistor vs ? analogy

    While I am not familiar with the details, I know there are thermal circuit models used in real applications. In particular, the analyzer made by these people: http://www.klippel.de/ uses a circuit model for the thermal behavior of a loudspeaker. Also, I don't see why these analogies have to...
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    Why do most subwoofers work best in a corner?

    Whoa there...the instance of the Klipsch horn is different because it is a horn. More generally, placing a standard monopole subwoofer in the corner as opposed to out in the room results in an increase in output for a couple reasons: - when you place the subwoofer in the corner, you are...
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    Completely Lost

    woops...forgot to define H- whatever function space you are working in
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