Mathematics

Associated with Math.SE; for both general discussion & math qu...
Mar 17, 2021 12:09
if you allow me to be politically incorrect, is it fair to say that integration happens on measure space and differentiation happens on norm spaces and these two concept coincide/related only when the underlying spaces is both norm and measurable space.
Jul 12, 2020 17:23
A while ago I was reading Frobenius theorem (manifold) and although I didn't understand it completely, a key takeaway was the existence of integral manifolds which was used to prove the existence of solution on 1st order homogenous linear PDE. This got me thinking that to prove the higher order inhomogenous case, we (if possible) can extend this theorem for a tensor field. Is there any research/result in this direction.
Jul 12, 2020 17:20
Hi to everybody and nobody
May 22, 2020 14:57
start ChatJax
May 22, 2020 14:53
Is it something related to the det that occurs in a change of variable
May 22, 2020 14:52
I am reading Lee book on smooth manifold. In the chapter Differential form, he starts with saying that we cannot define multiple integral of a function in a coordinate independent way of a manifold and gives the following example Let $f: C \rightarrow \mathbb{R}$ where C is a unit cube and f is a const funtion = 1. Then $\int_C fdx = $ Vol(C) is not invariant under coordinate transf. My problem is I dont understand the above statement that why Vol(C) not invariant under coordinate tranf.
May 1, 2019 15:47
(X,M,u) be a measurable space. Suppose $A \in M$, then is it always true that $A$ has a measure (finite or infinite)
Nov 20, 2018 04:28
this time it is word to word exact
Nov 20, 2018 04:27
actually I asked the same question on the main site. feel free to look at it math.stackexchange.com/questions/3005915/…
Nov 20, 2018 04:22
Yes I am drawing from sequence, but I have to find words from which words like BAD or CAD are formed. hence words like ADB are legit
Nov 20, 2018 04:17
the answer is given to be 6/216, but I got 12/216 (which is 2/216*3! if you consider the permutation of letters)
Nov 20, 2018 04:10
216 it is
Nov 20, 2018 04:10
sorry typo
Nov 20, 2018 04:03
yes accepted
Nov 20, 2018 03:54
also you are forgetting to permute it among themselves, then you will get the same answer as me
Nov 20, 2018 03:47
sorry I didn't understand what you are trying to say
Nov 20, 2018 03:33
*chosen random with replacement
Nov 20, 2018 03:33
but the textbook answer is 6/256
Nov 20, 2018 03:33
my answer is 12/256
Nov 20, 2018 03:32
From letteres A,B,C,D,E,F three letters are choosen at random. What is the probability that words BAD or CAD will be formed from choosen letter
Nov 20, 2018 03:31
Hi basic prob question?
Nov 18, 2018 22:36
oh I get your point, so you mean saddle like situation occurs here
Nov 18, 2018 22:32
The step in the derivation looked if and only if
Nov 18, 2018 22:32
Existence of extremal function
Nov 18, 2018 22:32
for minimal
Nov 18, 2018 22:31
Euler Lagrange equation (calculus of variatio) is necessay but not sufficient why?
Oct 27, 2018 01:58
now I got it
Oct 27, 2018 01:58
yes for every step of induction we need one eigen value
Oct 27, 2018 01:57
that would be an intresting example to check for me
Oct 27, 2018 01:55
Scheme of proof: One show that V has one invariant subspace W (which will turn out to eigen space), and then we use induction on V/W
Oct 27, 2018 01:54
suppose T is a linear tranf. over a vector space V over F sulch that all eigen value of T lies in F, then T can be written as triangular matrix? I think I weaken the hypothesis of the above theorem by requiring atleast eigen value is in F. Am I right in saying so?
Oct 27, 2018 01:02
Is my proof right?
Oct 27, 2018 01:02
= v(m(y)) = 0 implies m(y) = 0
Oct 27, 2018 01:01
then m(T)v = 0v = 0
 

 The h Bar

General chat for Physics SE (physics.stackexchange.com). For M...
Apr 14, 2020 16:31
yeah i think earlier I was mixing newtonian wave with wave equation.
Apr 14, 2020 16:30
actually mass controls the acceleration due to external potential. And also shrondinger equation has mass term, hence the evolution of wave equation is determined by the mass of the particle.
Apr 14, 2020 16:26
let me think about it for a moment
Apr 14, 2020 16:22
actually that what i wrote that mass should be irrelevant in physics in the last part of my statement. But somehow this statement seems to me a bit radical and hence wanted to confirm
Apr 14, 2020 16:20
and wave and particles both have momentum (although defined by different formula in each case). Is this the right intrepretation.
Apr 14, 2020 16:20
Hi, everyone. I was thinking about quantum-mechanics when the following thought came to me. Consider a particle like electron. By de-borgli equation, this electron has a wave equation $\psi$. Now we know that electron has mass but waves doesn't, so how do I account for mass of electron in the $\psi$ description. One way I thought a way out of this conundrum is the mass is irrelevant and only momentum is relevant,
Apr 13, 2020 22:28
okay nice talking to u, see u soon,
Apr 13, 2020 22:26
so if i have to understand the quatum behavious of light, I have to study QFT?
Apr 13, 2020 22:21
quantum mechanics
Apr 13, 2020 22:19
from ur preivous comment i get the impresssion that study of photon doens't come under QM, is that what u were saying
Apr 13, 2020 22:18
noted
Apr 13, 2020 22:09
@vzn if you are not busy I would like to hear both the pov
Apr 13, 2020 21:44
Greeting everyone, I have a conceptual difficulty. Light, as we know, can be considered as a photon as well as EM wave. The photon has a QM description given by wavefunction. Now I want to know what is the relation between wavefunction and EM wave equation (Similar questions have been asked before in physics se but I didn't understand it well).
 

 English Language & Usage: Multi-Layer

Not for the faint of heart or those easily triggered by Englis...
Mar 5, 2019 14:35
but the answer says it is a noun
Mar 5, 2019 14:35
WHILE according to me should be a adverb
Mar 5, 2019 14:34
Identify the part of speech: Sit down and rest a WHILE