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Differential Geometry

Do non-orthogonal coordinate systems mean dependent coordinates?
4.6K threads
Undergrad Do non-orthogonal coordinate systems mean dependent coordinates?
Undergrad Fiber bundle homeomorphism with the fiber
  • cianfa72
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Undergrad On deriving the (inverse) Fourier transform from Fourier series
  • psie
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Undergrad Prove projection of a measurable set from product space is measurable
  • Lagrange fanboy
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High School Questions on a numberphile video
  • picketpocket826
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Undergrad ##SU(2, \mathbb C)## parametrization using Euler angles
  • cianfa72
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Undergrad Regarding Wirtinger's inequality
  • psie
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Undergrad ##SL(2,\mathbb R)## Lie group as manifold
  • cianfa72
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High School A Question Relating Sum of Angles and Breaking of the Parallel Postulate
  • walkeraj
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Undergrad ##1^x =2## has complex solutions?
  • Arjan82
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7
Undergrad Is the Projection Restriction to a Linear Subspace a Homeomorphism?
  • cianfa72
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Undergrad New Video Course on General Topology on YouTube
  • caffeinemachine
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Undergrad On a proof of the converse of the supporting hyperplane theorem
  • psie
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Undergrad ##SU(2)## homeomorphic with ##\mathbb S^3##
  • cianfa72
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Undergrad Bloch Analysis proof of Theorem 2.5.5 (Definition by recursion)
  • BugKingpin
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Undergrad How do I use the four axioms of a neighborhood to define an open set?
  • learning physics
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Undergrad How to define an open set using the four axioms of a neighborhood
  • learning physics
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Undergrad Is the Belt Trick Possible with Continuous Deformation in 3D Rotation Space?
  • cianfa72
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Undergrad On differentiability and Fourier coefficients (Vretblad's text)
  • psie
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Graduate Complex analysis -- Essential singularity
  • LagrangeEuler
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6
Undergrad On limit of convolution of function with a summability kernel
  • psie
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Undergrad Fourier coefficients of convolution
  • psie
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Undergrad Outer measure .... Axler, Result 2.14 .... Another Question ....
  • Math Amateur
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8
Undergrad Bounding modulus of complex logarithm times complex power function
  • psie
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4
High School Confusion with the basics of Topology (Poincare conjecture)
  • shiv23mj
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Undergrad Is a Locally One-to-One Proper Map Globally Bijective?
  • Ashley1209
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Undergrad On a remark regarding the Cauchy integral formula
  • psie
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Undergrad Continuity of Quotient of Complex Values
  • thatboi
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5
Undergrad Complex function, principal value notation
  • Hill
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5
Undergrad Infinity Numbers (Expanded P-Adic Numbers)
  • Lokalgott
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10
High School Getting from complex domain to real domain
  • jaydnul
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3
Undergrad Naming convention for "Functional Variance"?
  • quasar987
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7
Undergrad Why is this function not ##L^1(\mathbb{R} \times \mathbb{R})##?
  • laurabon
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6
High School Why is the set {(x,y)∈Ω×R|y=f(x)} a manifold?
  • SaschaSIGI
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6
Graduate Topology - Boundary of a ball without a point
  • physics1000
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5
Graduate Why the triangle inequality is greater than the 2 max{f(x),g(x)}
  • cbarker1
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Undergrad Feedback for my YouTube Videos on Real Analysis
  • caffeinemachine
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4
High School How Do Dedekind Cuts Affect Addition and Negative Numbers?
  • bhobba
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Undergrad Using Residues (Complex Analysis) to compute partial fractions
  • cbarker1
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4
Undergrad Is the Set of Integer Outputs of sin(x) Sequentially Compact in ℝ?
  • MidgetDwarf
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Graduate Even with a whimsical mathematical usage, solutions are obtained!
  • Z-10-46
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Undergrad Circuits or edge-disjoint unions of circuits in a connected graph
  • cianfa72
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Undergrad How can you represent a point by "z = x + iy" as shown here?
  • Slimy0233
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Undergrad Can you somehow make left handed helix into a right handed?
  • sol47739
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Outer measure .... Axler, Result 2.8 ....
  • Math Amateur
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2
Undergrad Calculate the residue of 1/Cosh(pi.z) at z = i/2 (complex analysis)
  • Old Person
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7
High School Mapping wave forms to sphere, does wave form y=0 have a reflection?
  • bahamagreen
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High School Is this a complex number at the second quadrant?
  • mcastillo356
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7
High School Wolfram Alpha's Why the 2 i π n?
  • OmCheeto
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3
High School Aperiodic Tiling with a single tile shape
  • .Scott
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5
Graduate Regarding fibrations between smooth manifolds
  • aalma
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Undergrad Geometry of series terms of the Riemann Zeta Function
  • Swamp Thing
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3
Undergrad I need a mapping from the unit Hypercube [0,1]^n to a given simplex
  • benorin
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Undergrad Discrete Subrings of Complex Numbers: Topology of Rings
  • Paul Colby
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11
Checking Proof of Theorem 6.2.8 Part (ii)
  • Math Amateur
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Undergrad I would like opinions of the latest draft of my note - Integration
  • benorin
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4
Undergrad Upper and Lower Darboux Sum Inequality
  • Magnetons
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2
Graduate Question about the Poincaré conjecture
  • donglepuss
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3
Undergrad Original definition of Riemann Integral and Darboux Sums
  • Hall
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14
How to Prove \(\text{vol}_n (B) = \text{vol}_n (B') + \text{vol}_n (B'')\)?
  • Math Amateur
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Graduate Infinite series of this type converges?
  • mathman
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5
Undergrad In a 3-dimension isoperimetric problem, a ball maximizes the volume
  • graphking
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6
Undergrad Create a surjective function from [0,1]^n→S^n
  • laurabon
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Undergrad Lars Olsen proof of Darboux's Intermediate Value Theorem for Derivatives
  • Hall
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9
Graduate Norm 2, f Integrable function, show: ##||f-g||_2<\epsilon##
  • physics1000
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5
Undergrad Does topology distinguish between real and imaginary dimensions?
  • Feynstein100
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Undergrad Proof of i-th Root of i: Analytic Connection?
  • Gear300
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Undergrad Understanding the Role of the Identity Map in Fundamental Group Theory
  • Mikaelochi
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2
How to Prove a Complex Number Equation and Its Trajectory Forms a Circle?
  • WMDhamnekar
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Graduate What is the significance of the Poincaré conjecture?
  • donglepuss
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1
Undergrad Understanding an argument in Intermediate Value Theorem
  • Hall
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5
Undergrad Applications of complex gamma (or beta) functions in physics?
  • nomadreid
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6
Undergrad Are there any elementary functions of norms that are still norms?
  • askmathquestions
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4
Undergrad Applications of measurement of commutativity
  • askmathquestions
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5
Graduate Ref: "Standard" Action of S^1 on S^n ?
  • WWGD
  • · Replies 64 ·
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High School Is the Texan Conjecture a mathematical truth or a myth?
  • thetexan
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5
The Supremum of a Set is not an Interior Point
  • OhMyMarkov
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2
Question via email about complex numbers
  • Prove It
  • · Replies 1 ·
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1
Effie's question via email about Complex Numbers
  • Prove It
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2
Can This Forgotten Formula Simplify the Laplace Transform of \(y(t)^3\)?
  • chisigma
  • · Replies 1 ·
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Sava's question via email about solving complex number equations
  • Prove It
  • · Replies 1 ·
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1
Undergrad If a sequence converges, then all subsequences of it have same limit
  • Hall
  • · Replies 7 ·
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7
How Can I Tackle Difficult Questions Effectively?
  • jaychay
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2
Undergrad Who Rediscovered Archimedes' Lemma in Modern Mathematics?
  • Gear300
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5
Undergrad Simplify Tricky Equation for Purely Imaginary C with Complex Constants
  • thatboi
  • · Replies 5 ·
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5
Graduate Laurent series for algebraic functions
  • the_pulp
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9
Proving Measure Space Properties of $(X,\bar{\mathcal{B}} ,\bar{\mu})$
  • fabiancillo
  • · Replies 2 ·
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Graduate PD code yields two different knot diagrams
  • sophiatev
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3
Undergrad How can I use the concept of a proper map to show that a set is bounded?
  • cbarker1
  • · Replies 18 ·
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18
Undergrad Rewriting the Toeplitz Conjecture
  • MevsEinstein
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7
Undergrad ##\epsilon - \delta## proof and algebraic proof of limits
  • Hall
  • · Replies 48 ·
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High School Does this help solve the Riemann Hypothesis?
  • MevsEinstein
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Prove that the function is monotonic and not decreasing
  • fabiancillo
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High School Is the 10 Dimensional Poincaré Group a Coincidence?
  • Paige_Turner
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Graduate What does the metric of a 6D space with 3 compactified dimensions look like?
  • JandeWandelaar
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20
Undergrad Is it valid to express a complex number as a vector?
  • Mayhem
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8
Undergrad The asymptotic behaviour of Elliptic integral near k=1
  • julian
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2
Undergrad I need integrals Int[0,infty]t^(a-1) e^(-t) F(z, e^(-t))dt
  • benorin
  • · Replies 4 ·
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4
High School Is the Geometry/Topology of Mazes a thing?
  • DaveC426913
  • · Replies 18 ·
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18
Proving Relatively Compactness in C([a, b]) using Arzelá-Ascoli Theorem
  • fabiancillo
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Prove that it converges uniformly
  • fabiancillo
  • · Replies 2 ·
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