I'm currently working through chapter 7 on Riemannian geometry in Nakahara's book "Geometry, topology & physics" and I'm having a bit of trouble reproducing his calculation for the metric compatibility in a non-coordinate basis, using the Ricci rotation coefficients...
I have an equation that says $$C_1\partial_{\mu}G^{\mu\nu}+C_2\frac{1}{2}\epsilon^{\mu\nu\rho\sigma}\partial_{\mu}G_{\rho\sigma}=0$$ If I want to get rid of the ##\epsilon^{\mu\nu\rho\sigma}## in the second term, I know I must multiply the equation by some other ##\epsilon## with different set...
Hi,
Want to know (i) what does Riemannian metric tensor and Christoffel symbols on R2 mean? (ii) How does metric tensor and Christoffel symbols look like on R2? It would be great with an example as I am new to this Differential Geometry.
I'm trying to show that the lie derivative of a tensor field ##t## along a lie bracket ##[X,Y]## is given by \mathcal{L}_{[X,Y]}t=\mathcal{L}_{X}\mathcal{L}_{Y}t-\mathcal{L}_{Y}\mathcal{L}_{X}t
but I'm not having much luck so far. I've tried expanding ##t## on a coordinate basis, such that...
I'm studying General Relativity and Differential Geometry. In my textbook, the author has written ##x^2=d(x,.)## where d(x,y) is distance between two points ##x,y\in M##. I couldn't understand what d(x,.) means. Moreover, I am not sure if this is generally true to write ##x^2=g_{\mu\nu} x^\mu...
I am looking to pick up one of these texts, but I don't really want to buy all three. Is there a considered favorite? Thanks in advance.
B. O'Neill: Semi-Riemannian Geometry with Applications to Relativity
T. Frankel: The Geometry of Physics
B. Schutz: Geometrical Methods of Mathematical Physics
I thought about the Taylor expansion on a Riemannian manifold and guess the Taylor expansion of ##f## around point ##x=x_0## on the Riemannian manifold ##(M,g)## should be something similar to:
f(x) = f(x_0) +(x^\mu - x_0^\mu) \partial_\mu f(x)|_{x=x_0} + \frac{1}{2} (x^\mu - x_0^\mu) (x^\nu -...
Homework Statement
I am trying to derive the curvature tensor by finding the commutator of two covariant derivatives. I think I've got it, but my head is spinning with Nablas and indices. Would anyone be willing to check my work? Thanks
Homework Equations
I am trying to derive the curvature...
I'm in my last semester of my undergraduate majoring in mathematics (focusing on mathematical physics I guess - I'm one subject short of having a physics major) and am wondering, largely from a physics perspective if it would be better to do a functional analysis course or a differential...
This stems from considering rigid body transformations, but is a general question about total derivatives. Something is probably missing in my understanding here. I had posted this to math.stackexchange, but did not receive any answers and someone suggested this forum might be more suitable.
A...
I have recently had a lengthy discussion on this forum about coordinate charts which has started to clear up some issues in my understanding of manifolds. I have since been reading a few sets of notes (in particular referring to John Lee's "Introduction to Smooth Manifolds") and several of them...
I have just been asked why we use curvilinear coordinate systems in general relativity. I replied that, from a heuristic point of view, space and time are relative, such that the way in which you measure them is dependent on the reference frame that you observe them in. This implies that...
Hello, I am studying for an analytic geometry final but I am totally lost for this problem... We didn't even cover this topic in class (my prof didn't show up for class for two weeks) and I have no clue on how to do it. If anyone could help I would appreciate it.
Question: Prove that the...
I've been struggling since starting to study differential geometry to justify the definition of a one-form as a differential of a function and how this is equal to a tangent vector acting on this function, i.e. given f:M\rightarrow\mathbb{R} we can define the differential map...
I'm relatively new to differential geometry and would like to check that this is the correct definition for the tensor product of (for simplicity) two one-forms \alpha,\;\beta\;\;\in V^{\ast} : (\alpha\otimes\beta)(\mathbf{v},\mathbf{w})=\alpha (\mathbf{v})\beta (\mathbf{w}) where...
I am currently looking at grad schools, and I am wondering if anyone knew who are the leading researchers in differential geometry. I know that question is a little vague considering how diverse differential geometry is, but I was hoping that something could direct me in the right direction...
Apologies if this isn't quite the right forum to post this in, but I was unsure between this and the calculus forum.
Something that has always bothered me since first learning calculus is how to interpret dx, essentially, what does it "mean"? I understand that it doesn't make sense to consider...
In all the notes that I've found on differential geometry, when they introduce integration on manifolds it is always done with top forms with little or no explanation as to why (or any intuition). From what I've manage to gleam from it, one has to use top forms to unambiguously define...
What is the motivation for defining vectors in terms of equivalence classes of curves? Is it just that the definition is coordinate independent and that the differential operators arising from such a definition satisfy the axioms of a vector space and thus are suitable candidates for forming...
I have a few conceptual questions that I'd like to clear up if possible.
The first is about directional derivatives in general. If one has a function f defined in some region and one wishes to know the rate of change of that function (i.e. its derivative) along a particular direction in that...
I am relatively new to the concept of differential geometry and my approach is from a physics background (hoping to understand general relativity at a deeper level). I have read up on the notion of diffeomorphisms and I'm a little unsure on some of the concepts.
Suppose that one has a...
I've been reading Sean Carroll's notes on General Relativity, http://arxiv.org/pdf/gr-qc/9712019.pdf . I've got to chapter 5 (page 133) and am reading the section on diffeomorphisms in which Sean relates diffeomorphisms to active transformations. When he says this does he mean that one defines a...
When I studied General Relativity using Misner, Thorne and Wheeler's "Gravitation", it was eye-opening to me to learn the geometric meanings of vectors, tensors, etc. The way such objects were taught in introductory physics classes were heavily dependent on coordinates: "A vector is a collection...
I've recently finished tackling differential equations. I want to start learning general relativity, but from what I've read, I need to have a firm footing in differential geometry first. So where do I start learning DG? I really don't want to do a half-hearted job in an attempt to quickly jump...
I am taking thermodynamics this semester as well as a course in differential geometry of surfaces, and I am seeing a lot of overlap.
For example, I can create a "state space" isomorphic to R3 of TxPxV I can then define a surface on this space of PV=NkT I can define quasi static state equations...
I understand that a tangent vector, tangent to some point p on some n-dimensional manifold \mathcal{M} can defined in terms of an equivalence class of curves [\gamma] (where the curves are defined as \gamma: (a,b)\rightarrow U\subset\mathcal{M}, passing through said point, such that \gamma (0)=...
I've been reading up on the definition of a tangent bundle, partially with an aim of gaining a deeper understanding of the formulation of Lagrangian mechanics, and there are a few things that I'm a little unclear about.
From what I've read the tangent bundle is defined as the disjoint union of...
This is a slightly physics oriented question, so apologies for that.
Basically, having started studying differential geometry it has started to become a little clearer to me why one can consider the Lagrangian as a function of position and velocity, but I don't feel I'm quite there yet.
My...
I have the hardback 5 volume set of Spivak's A Comprehensive Introduction to Differential Geometry that is in pretty good shape. Is there any value to that set? I tried looking it up, but I don't really see many people selling whole sets, so I can't tell...
Thanks.
Hello all,
I'm currently taking an upper undergraduate two part Mechanics course using the above mentioned book by its author.
He's a great professor and I was wondering if anyone else has checked out this book? It's very math heavy and I'm struggling with some of the language since I haven't...
I am currently working through Nakahara's book, "Geometry, Topology and Physics", and have reached the stage at looking at calculus on manifolds. In the book he states that "The differentiability of a function f:M\rightarrow N is independent of the coordinate chart that we use". He shows this is...
Hello,
This spring, I will have the opportunity to do a one-on-one independent study in math or physics. I've narrowed down my choices to differential geometry and general relativity. I'm thinking about the future here- will studying general relativity this spring better prepare me for...
Homework Statement
I'm having trouble figuring out how to use Christoffel symbols. Apart from the first three terms here, I can't understand what's going on between line 3 and 4. What formulas/definitions are being used? How do you find the product of two chirstoffel symbols? Where are all the...
Suppose that we have this metric and want to find null paths:
ds^2=-dt^2+dx^2
We can easily treat dt and dx "like" differentials in calculus and obtain for $$ds=0$$
dx=\pm dt \to x=\pm t
Now switch to the more abstract and rigorous one-forms in differentiable manifolds.
Here \mathrm{d}t (v)...
Suppose that we have this metric and want to find null paths:
ds^2=-dt^2+dx^2
We can easily treat dt and dx "like" differentials in calculus and obtain for $$ds=0$$
dx=\pm dt \to x=\pm t
Now switch to the more abstract and rigorous one-forms in differentiable manifolds.
Here \mathrm{d}t (v)...
I'm trying to learn how to think about principal bundles where the fibre is a lie group with local trivialization ϕ^{-1}_i:π(U_i)→U_i×G . For example ϕ^{-1}_i:π(S^2)→S^2×U(1) (if that makes sense) . But I don't know how to think of this (and other products with lie groups like that)...
If I want to take the wedge product of $$\alpha = a_i\theta^i $$ and $$\beta = b_j\theta^j$$ I get after applying antisymmetrization,$$ \alpha \Lambda \beta = \frac{1}{2}(a_ib_j - a_jb_i)\theta^i\theta^j$$
My question is it seems to me that antisymmetrization technique doesn't apply to the...
Homework Statement
Suppose that ##s \to A(s) \subset \mathbb{M}_{33}(\mathbb{R})## is smooth and that ##A(s)## is antisymmetric for all ##s##. If ##Q_0 \in SO(3)##, show that the unique solution (which you may assume exists) to
$$\dot{Q}(s) = A(s)Q(s), \quad Q(0) = Q_0$$
satisfies ##Q(s) \in...
Hi. I am looking for the most basic intro to differential geometry with plenty of worked examples. I want it to cover the following - differential forms , pull-backs , manifolds , tensors , metrics , Lie derivatives and groups and killing vectors. Problems with solutions would also be good as I...
I am planning on taking a course in differential geometry. I have looked at the notes and they cover - differential forms , pull-backs , tangent vectors , manifolds , Stokes' theorem , tensors , metrics , Lie derivatives and groups and killing vectors. I have a book called Elementary...
I'm looking for a book or two that details affine spaces and transformations, then differential geometry of surfaces in affine spaces, starting at a level suitable for a year 1-2 undergraduate. In particular, I'd like to understand a few properties (e.g. what's the gradient and curvature at a...
I bought a book (Differential Geometry by Kreyszig) based on really good reviews because I'm planning to learn general relativity later. I guess I didn't pay enough attention to the description because apparently it's completely focused on "three-dimensional Euclidean space."
Will this book...
Also, is there a special term for the geometry typically taught in high school?
And how does topology fit in here? It seems that topology is a form of geometry as well.
even γ: I-> R ^ 2 curve parameterized as to arc length (single speed) with curvature k (s)> 0 and torsion τ(s)> 0. I want to write the γ(s) as a combination of n(s), t(s), b(s). these are the types of Frenet.
the only thing i know is that the types of Frenet are t(s)=γ'(s) ...
Consider the surface S defined as the graph of a function z = 2x ^ 2 - y ^ 2
i) find a basis of the tangent plane Tp surface S at the point p = (-1,2, -2)
ii) find a non-zero vector w in Tp with the property that the vertical curvature at point p in the direction of vector w is zero
for...
whether γ=γ(s):I->R^3 curve parameterized as to arc length (single speed). Assume that γ is the surface sphere centered on the origin (0,0). Prove that the vector t(s) is perpendicular to the radius of the sphere at point γ(s), for each s.
i know that t(s)=γ΄(s) but i don't know how to...
Any good textbooks on differential geometry for self study?
I'm not the best at reading comprehension. I've already studied Calculus, differential equations, and linear algebra.
I have a Physics background and have done the relevant maths ie. calculus , linear algebra , vector calculus and differential equations. Do i need any "extra maths" before starting a course in differential geometry ? Any recommendations for a book on the subject that would suit a Physicist ?
Thanks