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A Primer in Bifurcation Theory for Computational Cell Biologists Lecture 7: Fold-Hopf Bifurcation. http://www.biology.vt.edu/faculty/tyson/lectures.php. John J. Tyson Virginia Polytechnic Institute & Virginia Bioinformatics Institute. Click on icon to start audio. degenerate Hopf. cusp. - PowerPoint PPT Presentation
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A Primer in Bifurcation Theoryfor Computational Cell BiologistsLecture 7: Fold-Hopf Bifurcation
John J. TysonVirginia Polytechnic Institute
& Virginia Bioinformatics Institute
http://www.biology.vt.edu/faculty/tyson/lectures.php
Click on iconto start audio
Codimension-Two Bifurcations
p
qs
sxss
cusp supHB
CF
s
u
ssubHB
p
degenerate Hopf
q
s
sxs
uxs
s
Takens-Bogdanov
p
SN
s xs
SL
subHB
q
p
uxs
SL
u xs
u
SN
SNIC
Saddle-Node Loop
q
Takens-Bogdanov Bifurcations
1,2
1
Re ( , ) 0 (Hopf)
( , ) 0 (fold)
( , ) 0 (steady state)
x p
x p
f x p
p1
p2
x1
saddle-loop
p1
SN
SL
HB
p2
Fold-Hopf Bifurcation
1
2,3
( , ) 0 (steady state)
( , ) 0 (fold)
Re ( , ) 0 (Hopf)
f x p
x p
x p
p1
p2
x1
p1
p2
2
3
4
1
SNHopf
Minimum number of variables for fold-Hopf bifurcation is three:
1 2 3 1 2 3( , , ) ( , , ) where ix x x x x ix e
x1
constant angular velocity in
x1
x2
x3
x1
x1
SN
SN
HB
HB
x1
x1
p1SN SNHB HB
(+ − −)
(− − −)(− + +)
(+ + +)
CASE 1
SN
SN
HB
HB
x1
x1
p1SN SNHB HB
(+ − −)
(− − −) (− + +)
(+ + +)
CASE 2
SN
SN
HB
HB
CASE 3Torus
x1x1
Heteroclinic
Torus
SN
SN
HB
HB
CASE 3Torus
Heteroclinic
x1
p1SN SNHB HBToHe
CASE 4
From Kuznetsov’s Book
CASE 4
x1
p1
SN SNHB HB To
‘CycleBlowup’
CASE 1
From Kuznetsov’s Book
CASE 2
CASE 3