Questions tagged [physics]
Questions on the mathematics required to solve problems in physics. For questions from the field of mathematical physics use (mathematical-physics) tag instead.
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Importance of Representation Theory
Representation theory is a subject I want to like (it can be fun finding the representations of a group), but it's hard for me to see it as a subject that arises naturally or why it is important. I ...
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Why do units (from physics) behave like numbers?
What are units (like meters $m$, seconds $s$, kilogram $kg$, …) from a mathematical point of view?
I've made the observation that units "behave like numbers". For example, we can divide them (as in $...
user377104
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Good Physical Demonstrations of Abstract Mathematics
I like to use physical demonstrations when teaching mathematics (putting physics in the service of mathematics, for once, instead of the other way around), and it'd be great to get some more ideas to ...
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Why can't you add apples and oranges, but you can multiply and divide them?
What is the algebraic difference between arithmetic operations, that prevents entities with different units from being summed or subtracted, but allows them to be multiplied or divided?
This looks ...
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What is the meaning of the third derivative of a function at a point
(Originally asked on MO by AJAY.)
What is the geometric, physical, or other meaning of the third derivative of a function at a point?
If you have interesting things to say about the meaning of the ...
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Very *mathematical* general physics book
I am searching for a book to study physics. So far, I've been suggested
Resnick, Halliday, Krane, Physics,
but it doesn't seem to be very suited for a math major. Can you suggest some more ...
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Is learning (theoretical) physics useful/important for a mathematician?
I'm starting to read The Princeton Companion to Mathematics, at the beginning it says:
A proper appreciation of
pure mathematics requires some knowledge of applied
mathematics and theoretical ...
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Teenager solves Newton dynamics problem - where is the paper?
From Ottawa Citizen (and all over, really):
An Indian-born teenager has won a research award for solving a
mathematical problem first posed by Sir Isaac Newton more than 300
years ago that has ...
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Why learn to solve differential equations when computers can do it?
I'm getting started learning engineering math. I'm really interested in physics especially quantum mechanics, and I'm coming from a strong CS background.
One question is haunting me.
Why do I need ...
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Xmas Maths 2015
Simplify the expression below into a seasonal greeting using commonly-used symbols in commonly-used formulas in maths and physics. Colours are purely ornamental!
$$
\begin{align}
\frac{
\color{green}{...
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Dirac Delta Function of a Function
I'm trying to show that
$$\delta\big(f(x)\big) = \sum_{i}\frac{\delta(x-a_{i})}{\left|{\frac{df}{dx}(a_{i})}\right|}$$
Where $a_{i}$ are the roots of the function $f(x)$. I've tried to proceed by ...
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reference for multidimensional gaussian integral
I was reading on Wikipedia in this article about the n-dimensional and functional generalization of the Gaussian integral. In particular, I would like to understand how the following equations are ...
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Intuitive reasoning behind $\pi$'s appearance in bouncing balls.
This video is about an interesting math/physics problem that when cranked out churns out digits of $\pi$.
Is there an intuitive reason that $\pi$ is showing up instead of some other funky number ...
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What is a simple, physical situation where complex numbers emerge naturally? [duplicate]
I'm trying to teach middle schoolers about the emergence of complex numbers and I want to motivate this organically. By this, I mean some sort of real world problem that people were trying to solve ...
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Physicists, not mathematicians, can multiply both sides with $dx$ - why?
The following question is asked without malicious intentions - it's not intended as a flamebait!
In my physics textbooks (Young & Freedman in particular) I have often seen derivations of ...
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