Sebastian Casalaina

Homework and Syllabus

Differential Geometry of Curves and Surfaces

MATH 4230/5230 Fall 2026

⚠ >>WARNING: PAGE UNDER CONSTRUCTION -- SUBJECT TO CHANGE<< ⚠

Read the suggested material before class. After class, attempt the exercises listed for that day. Submit work through Canvas. Clear, logically organized exposition is required for all work in this class.

You may find the Math Academic Resource Center useful as a place to discuss course material and receive additional help.

An asterix * indicates that a homework assignment has not been finalized.

No classHomework due / reviewExam/general reviewMidterm or final

Date Topics Reading Homework / review material
L1
Friday, August 21
Parametrized curves: regularity, speed, and arc length Tapp §1.1, pp. 2–8 HW 1(a)Tapp Exercises: 1.5, 1.6, 1.7, 1.8, 1.9, 1.10*
L2
Monday, August 24
Inner products, projections, and orthonormal bases Tapp §1.2, pp. 9–15 HW 1(b)Tapp Exercises: 1.15, 1.16, 1.17, 1.18, 1.19, 1.20*
L3
Wednesday, August 26
Acceleration and reparametrization Tapp §§1.3–1.4, pp. 16–23 HW 1(c)Tapp Exercises: 1.26, 1.27, 1.28, 1.29, 1.31, 1.33*
L4
Friday, August 28
Curvature, unit tangent and normal vectors, and osculating circles Tapp §1.5, pp. 24–31 HW 1 Due
HW 2(a)Tapp Exercises: 1.36, 1.37, 1.38, 1.40, 1.41, 1.43*
L5
Monday, August 31
Plane curves: signed curvature, angle functions, and rotation index Tapp §1.6, pp. 32–40 HW 2(b)Tapp Exercises: 1.44, 1.45, 1.46, 1.47, 1.48, 1.49*
L6
Wednesday, September 2
Space curves: Frenet frame, torsion, and Frenet equations Tapp §1.7, pp. 41–47 HW 2(c)Tapp Exercises: 1.62, 1.63, 1.64, 1.65, 1.66, 1.68*
L7
Friday, September 4
Rigid motions, fundamental theorems, and curvature formulas Tapp §§1.8–1.9, pp. 48–60 HW 2 Due
HW 3(a)Tapp Exercises: 1.70, 1.71, 1.75, 1.76, 1.78, 1.83*
Monday, September 7 Labor Day No class; university closed. No exercises assigned.
L8
Wednesday, September 9
Hopf’s Umlaufsatz and the Jordan curve theorem Tapp §2.1, pp. 61–67 HW 3(b)Tapp Exercises: 1.52, 1.55, 1.58, 2.1, 2.2, 2.3*
L9
Friday, September 11
Piecewise-regular curves and the generalized Umlaufsatz Tapp §2.1, pp. 68–71 HW 3 Due
HW 4(a)Tapp Exercises: 1.56, 1.57, 1.59, 1.60, 1.69, 1.82*
L10
Monday, September 14
Green’s theorem I: vector fields, line integrals, and conservative fields Tapp §2.4, pp. 81–89 HW 4(b)Tapp Exercises: 2.17, 2.18, 2.19, 2.20, 2.21, 2.22*
L11
Wednesday, September 16
Green’s theorem II: circulation, divergence, and flux Tapp §2.4, pp. 90–96 HW 4(c)Tapp Exercises: 2.21, 2.23, 2.24, 2.25, 2.26, 2.27*
L12
Friday, September 18
Review: homework review Review Tapp Chapters 1–2 HW 4 Due
Six focus problems from the assigned homework: 1.31, 1.38, 1.48, 1.65, 2.18, 2.26.
L13
Monday, September 21
Review: general review for Midterm I Review all nonoptional material in Tapp Chapters 1–2 Six cumulative review problems: 1.10, 1.20, 1.33, 1.52, 1.64, 2.24.
L14
Wednesday, September 23
Review: Midterm I practice exam Practice exam and solutions will be posted on Canvas. Complete the six-problem practice exam before class;
bring questions.
L15
Friday, September 25
MIDTERM I Tentative scope: nonoptional material in Tapp Chapters 1–2 No new exercises assigned.
L16
Monday, September 28
Derivatives of maps from Euclidean space to Euclidean space Tapp §3.1, pp. 113–124 HW 5(a)Tapp Exercises: 3.1, 3.2, 3.3, 3.4, 3.5, 3.9*
L17
Wednesday, September 30
Review Midterm I Review the returned exam, common errors, and solution strategies. No new exercises assigned; bring your exam and corrected solutions.
L18
Friday, October 2
Regular surfaces: patches, level sets, ruled surfaces, and examples Tapp §3.2, pp. 125–140 HW 5 Due
HW 6(a)Tapp Exercises: 3.13, 3.15, 3.18, 3.20, 3.23, 3.29*
L19
Monday, October 5
Tangent planes and derivatives of maps between surfaces Tapp §3.3, pp. 141–146 HW 6(b)Tapp Exercises: 3.35, 3.36, 3.38, 3.40, 3.43, 3.46*
L20
Wednesday, October 7
Area distortion, orientation, and orientable surfaces Tapp §§3.4–3.5, pp. 147–159 HW 6(c)Tapp Exercises: 3.51, 3.54, 3.57, 3.59, 3.63, 3.72*
L21
Friday, October 9
Surface area, isometries, and the first fundamental form Tapp §§3.6–3.7, pp. 160–169 HW 6 Due
HW 7(a)Tapp Exercises: 3.74, 3.76, 3.79, 3.80, 3.83, 3.85*
L22
Monday, October 12
The first fundamental form in local coordinates Tapp §3.9, pp. 182–187 HW 7(b)Tapp Exercises: 3.100, 3.101, 3.103, 3.105, 3.107, 3.108*
L23
Wednesday, October 14
The Gauss map and the Weingarten map Tapp §4.1, pp. 195–200 HW 7(c)Tapp Exercises: 4.1, 4.2, 4.3, 4.4, 3.102, 3.104*
L24
Friday, October 16
Self-adjoint maps, the spectral theorem, and principal directions Tapp §4.2, pp. 201–205 HW 7 Due
HW 8(a)Tapp Exercises: 4.5, 4.6, 4.7, 4.8, 3.106, 3.109*
L25
Monday, October 19
Normal curvature, principal curvatures, Gaussian curvature, and mean curvature Tapp §4.3, pp. 206–212 HW 8(b)Tapp Exercises: 4.9, 4.10, 4.12, 4.14, 4.16, 4.18*
L26
Wednesday, October 21
Geometric characterizations of Gaussian curvature Tapp §4.4, pp. 213–216 HW 8(c)Tapp Exercises: 4.19, 4.20, 4.21, 4.22, 4.23, 4.24*
L27
Friday, October 23
Review: homework review Review Tapp Chapters 3–4 through §4.4 HW 8 Due
Six focus problems from the assigned homework: 3.9, 3.23, 3.43, 3.72, 3.105, 4.18.
L28
Monday, October 26
The second fundamental form in local coordinates Tapp §4.5, pp. 217–226 HW 9(a)Tapp Exercises: 4.25, 4.28, 4.30, 4.31, 4.33, 4.40*
L29
Wednesday, October 28
Review: general review for Midterm II Review all nonoptional material in Tapp Chapters 3–4 Six cumulative review problems: 3.5, 3.29, 3.46, 3.79, 4.8, 4.24.
L30
Friday, October 30
Review: Midterm II practice exam Practice exam and solutions will be posted on Canvas. HW 9 Due
Complete the six-problem practice exam before class;
bring questions.
L31
Monday, November 2
MIDTERM II Tentative scope: nonoptional material in Tapp Chapters 3–4 No new exercises assigned.
L32
Wednesday, November 4
Geodesics: definitions, examples, and Clairaut’s theorem Tapp §5.1, pp. 247–256 HW 10(a)Tapp Exercises: 5.1, 5.2, 5.4, 5.5, 5.7, 5.9*
L33
Friday, November 6
The exponential map, Gauss’s lemma, and normal coordinates Tapp §5.2, pp. 257–267 HW 10 Due
HW 11(a)Tapp Exercises: 5.21, 5.22, 5.23, 5.24, 5.27, 5.32*
L34
Monday, November 9
Gauss’s Theorema Egregium, intrinsic curvature, and complete surfaces Tapp §§5.3–5.4, pp. 268–279 HW 11(b)Tapp Exercises: 5.33, 5.35, 5.39, 5.41, 5.43, 5.47*
L35
Wednesday, November 11
Review Midterm II Review the returned exam, common errors, and solution strategies. No new exercises assigned; bring your exam and corrected solutions.
L36
Friday, November 13
Parallel transport and the covariant derivative Tapp §5.5, pp. 280–288 HW 11 Due
HW 12(a)Tapp Exercises: 5.48, 5.49, 5.50, 5.52, 5.54, 5.55*
L37
Monday, November 16
Geodesics in local coordinates and curvature as infinitesimal holonomy Tapp §§5.6–5.7, pp. 289–302 HW 12(b)Tapp Exercises: 5.56, 5.58, 5.59, 5.64, 5.69, 5.71*
L38
Wednesday, November 18
The local and global Gauss–Bonnet theorems Tapp §§6.1–6.2, pp. 320–333 HW 12(c)Tapp Exercises: 6.1, 6.2, 6.3, 6.4, 6.7, 6.9*
L39
Friday, November 20
Compact surfaces, Euler characteristic, and other global theorems Tapp §§6.3–6.4, pp. 334–344 HW 12 Due
HW 13(a)Tapp Exercises: 6.10, 6.12, 6.15, 6.16, 6.18, 6.22*
Monday, November 23 Fall Break No class. No exercises assigned.
Wednesday, November 25 Fall Break No class. No exercises assigned.
Friday, November 27 Fall Break / Thanksgiving holiday No class; university closed. No exercises assigned.
L40
Monday, November 30
Review: homework review Review Tapp Chapters 5–6 Six focus problems from the assigned homework: 5.9, 5.23, 5.39, 5.50, 5.69, 6.9.
L41
Wednesday, December 2
Review: general review for the final examination Cumulative review of all nonoptional sections in Tapp Chapters 1–6 Six cumulative review problems: 1.38, 2.24, 3.46, 4.31, 5.47, 6.15.
L42
Friday, December 4
Review: final practice exam and course synthesis Six-problem cumulative practice final and solutions will be posted on Canvas. HW 13 Due
Complete the six-problem practice final before class;
bring questions.
Tuesday, December 8 FINAL EXAMINATION 1:30–4:00 PM
Room listed in Buff Portal
No new exercises assigned.

This schedule is subject to adjustment.