Physical examples of Hopf bifurcation, where a limit cycle is created from a fixed point: flutter of window blinds and airplane wings, oscillating chemical reactions (Belousov-Zhabotinsky reaction), gliding of flying squirrels. The Hopf bifurcation can occur in high dimensional systems and is robust to perturbations. Hopf bubbles. Global versus local stability of limit cycles.
► Next, global bifurcations in 2D
https://youtu.be/iphb2GlNtCk
► Playlist 'Nonlinear Dynamics and Chaos' (online course)
https://www.youtube.com/playlist?list=PLUeHTafWecAUqSh3Gy0NNr7H3OsXoC-aK
► Bifurcations in 2D
Zero eigenvalue bifurcations
https://youtu.be/pl3byZQkVd8
Hopf bifurcation theory
https://youtu.be/20O6v1X92P4
Hopf physical examples
https://youtu.be/4vOC7zw2YME
Bifurcations of limit cycles
https://youtu.be/iphb2GlNtCk
► Bifurcations in 1D (the zero eigenvalue bifurcations)
Saddle-node
https://youtu.be/BBd68_q3Dgg
Trans-critical
https://youtu.be/65ZKdscURXg
Pitchfork
https://youtu.be/W8rnh14bChA
Robustness
https://youtu.be/oQnWVmt_A3U
► Additional background on 2D dynamical systems
Phase plane introduction
https://youtu.be/U4IM7HFzcuY
Classifying 2D fixed points
https://youtu.be/7Ewe_tVa5Fs
Gradient systems
https://youtu.be/uGUzPZzvPWQ
Index theory
https://youtu.be/bO8FxxpocNQ
Limit cycles
https://youtu.be/9rVscJwDpBo
Averaging theory
https://youtu.be/UzQU1nyM-No
► Advanced lecture on Hopf bifurcations
https://youtu.be/MgmutdItm8Q
► Dr. Shane Ross, Virginia Tech professor (Caltech PhD)
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► Course lecture notes (PDF)
https://is.gd/NonlinearDynamicsNotes
► Courses and Playlists by Dr. Ross
📚Attitude Dynamics and Control
https://is.gd/SpaceVehicleDynamics
📚Nonlinear Dynamics and Chaos
https://is.gd/NonlinearDynamics
📚Hamiltonian Dynamics
https://is.gd/AdvancedDynamics
📚Three-Body Problem Orbital Mechanics
https://is.gd/SpaceManifolds
📚Lagrangian and 3D Rigid Body Dynamics
https://is.gd/AnalyticalDynamics
📚Center Manifolds, Normal Forms, and Bifurcations
https://is.gd/CenterManifolds
BZ reaction: A chemical oscillator — this chemical reaction changes color periodically, doesn’t settle down to equilibrium. It’s the Belousov–Zhabotinsky reaction, or BZ reaction, and mathematically it’s a limit cycle that arises from a Hopf bifurcation.
BZ reaction: https://en.wikipedia.org/wiki/Belousov–Zhabotinsky_reaction
References:
Steven Strogatz, "Nonlinear Dynamics and Chaos", Chapter 8: Bifurcations Revisited
Kirubakaran Purushothaman, Aeroelastic flutter demonstration using venetian blind strips,
https://youtu.be/r681ySdC1Zw
ICIQchem, Oscillating reactions – The chemical clock,
https://youtu.be/PYxInARIhLY
Jonathan Mitchell, When Math Drops the Bass - Hopf Bifurcation,
https://youtu.be/EtjdjrKu9Jk
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