In[214]:=

omegax = Pi omegay = 2 Pi RowBox[{Plot, [, RowBox[{{Cos[omegax t] , .5 Cos[omegay t]}, ,, {t,  ...  RowBox[{{, RowBox[{RowBox[{Thickness, [, 0.005, ]}], ,, RGBColor[0, 0, 1]}], }}]}], }}]}]}], ]}]

Out[214]=

Pi

Out[215]=

2 Pi

[Graphics:HTMLFiles/index_2.gif]

Out[216]=

-Graphics-

In[217]:=

RowBox[{, RowBox[{omegax = Pi, , RowBox[{omegay,  , =,  , RowBox[{2.3,  , Pi}] ... ness, [, 0.005, ]}], ,, RGBColor[0, 0, 1]}], }}]}], }}]}]}], ]}], , , }]}]

Out[217]=

Pi

Out[218]=

7.22566

[Graphics:HTMLFiles/index_4.gif]

Out[219]=

-Graphics-

In[220]:=

RowBox[{, RowBox[{x[t_] = Cos[Pi t], , dx[t_] = D[x[t], t], ,  ...  ParametricPlot[{x[t], y[t]}, {t, 1, 5500}, PlotStyle {{RGBColor[1, 0, 0]}}], }]}]

Out[220]=

Cos[Pi t]

Out[221]=

-(Pi Sin[Pi t])

[Graphics:HTMLFiles/index_6.gif]

Out[222]=

-Graphics-

Out[223]=

Cos[6.59734 t]

Out[224]=

-6.59734 Sin[6.59734 t]

[Graphics:HTMLFiles/index_7.gif]

Out[225]=

-Graphics-

[Graphics:HTMLFiles/index_8.gif]

Out[226]=

-Graphics-

[Graphics:HTMLFiles/index_9.gif]

Out[227]=

-Graphics-

Out[228]=

Cos[Pi t]

Out[229]=

-(Pi Sin[Pi t])

[Graphics:HTMLFiles/index_10.gif]

Out[230]=

-Graphics-

Out[231]=

Cos[Sqrt[2] Pi t]

Out[232]=

-(Sqrt[2] Pi Sin[Sqrt[2] Pi t])

[Graphics:HTMLFiles/index_11.gif]

Out[233]=

-Graphics-

In[162]:=

x[t_] = Cos[Pi t] Exp[-.1 t] dx[t_] = D[x[t], t]  ParametricPlot[{x[t], dx[t]} , {t, 1, 10}, PlotStyle {{RGBColor[1, 0, 0]}}]

Out[162]=

Cos[Pi t]
---------
  0.1 t
E

Out[163]=

-0.1 Cos[Pi t]   Pi Sin[Pi t]
-------------- - ------------
     0.1 t           0.1 t
    E               E

[Graphics:HTMLFiles/index_13.gif]

Out[164]=

-Graphics-

RowBox[{, , (*THE AXION*), (*Frank Wilczek -- Today ' s Nobel Prize ; also S . ... le {{RGBColor[0, 0, 1]}}, ,, AxesLabel-> {"t", "s"}}], ]}], ;}]}]}]

Out[209]=

{{a -> InterpolatingFunction[{{0., 15.}}, <>]}}

[Graphics:HTMLFiles/index_15.gif]

In[211]:=

sol1 = NDSolve[{a''[t] + 2/t a '[t] + Pi a[t] 0, a[1] 1, a '[1] == 0}, a, {t,  ...  ,, RGBColor[0, 1, 0]}], }}], }}]}], ,, AxesLabel-> {"t", "s"}}], ]}], ;}]

Out[211]=

{{a -> InterpolatingFunction[{{1., 50.}}, <>]}}

[Graphics:HTMLFiles/index_17.gif]

[Graphics:HTMLFiles/index_18.gif]

(*CHAOS*)

In[693]:=

omega = .7 c = .01 F = .02 Clear[x] sol1 = NDSolve[{x''[t] + c  x '[t] + Sin[x[t]] - ... ] ParametricPlot[{x[t], x '[t]}/.sol1 , {t, 1400, 1500}, PlotStyle {{RGBColor[1, 0, 0]}}]

Out[693]=

0.7

Out[694]=

0.01

Out[695]=

0.02

Out[697]=

{{x -> InterpolatingFunction[{{0., 1500.}}, <>]}}

[Graphics:HTMLFiles/index_21.gif]

[Graphics:HTMLFiles/index_22.gif]

Out[699]=

-Graphics-

[Graphics:HTMLFiles/index_23.gif]

Out[700]=

-Graphics-

In[701]:=

c = .03 F = .2 Clear[x] sol1 = NDSolve[{x''[t] + c  x '[t] + Sin[x[t]] - F Cos[omega ... ] ParametricPlot[{x[t], x '[t]}/.sol1 , {t, 1400, 1500}, PlotStyle {{RGBColor[1, 0, 0]}}]

Out[701]=

0.03

Out[702]=

0.2

Out[704]=

{{x -> InterpolatingFunction[{{0., 1500.}}, <>]}}

[Graphics:HTMLFiles/index_25.gif]

[Graphics:HTMLFiles/index_26.gif]

Out[706]=

-Graphics-

[Graphics:HTMLFiles/index_27.gif]

Out[707]=

-Graphics-

In[708]:=

c = .01 F = .6 Clear[x] sol1 = NDSolve[{x''[t] + c  x '[t] + Sin[x[t]] - F Cos[omega ... ] ParametricPlot[{x[t], x '[t]}/.sol1 , {t, 1400, 1500}, PlotStyle {{RGBColor[1, 0, 0]}}]

Out[708]=

0.01

Out[709]=

0.6

Out[711]=

{{x -> InterpolatingFunction[{{0., 1500.}}, <>]}}

[Graphics:HTMLFiles/index_29.gif]

[Graphics:HTMLFiles/index_30.gif]

Out[713]=

-Graphics-

[Graphics:HTMLFiles/index_31.gif]

Out[714]=

-Graphics-

In[722]:=

c = .03 F = .6 Clear[x] sol1 = NDSolve[{x''[t] + c  x '[t] + Sin[x[t]] - F Cos[omega ... ParametricPlot[{x[t], x '[t]}/.sol1 , {t, 10000, 15000}, PlotStyle {{RGBColor[1, 0, 0]}}]

Out[722]=

0.03

Out[723]=

0.6

Out[725]=

{{x -> InterpolatingFunction[{{0., 15000.}}, <>]}}

[Graphics:HTMLFiles/index_33.gif]

[Graphics:HTMLFiles/index_34.gif]

Out[727]=

-Graphics-

[Graphics:HTMLFiles/index_35.gif]

Out[728]=

-Graphics-

RowBox[{(*Here we very the initial conditions .   The transition to Chaos is Clearly ...  ,, {t, 0, 1500}, ,,  , MaxSteps1000000}], ]}]}], ;}], , x[1500]/.sol1}]}]

Out[1181]=

{0.0303327}

Out[1184]=

{0.0303277}

Out[1190]=

{-56.5483}

Out[1193]=

{-56.4883}

Out[1197]=

{13.8196}

Out[1200]=

{-47.4458}

In[753]:=

omega = .7 ; c = .03 ; F = .6 ; Clear[x] ; sol1 = NDSolve[{x''[t] + c  x '[t] + Sin[ ... [0] == 0}], }}], ,, x, ,, {t, 0, 1500}, ,,  , MaxSteps1000000}], ]}]}], ;}] x[1500]/.sol1

Out[758]=

{-101.73}

Out[761]=

{84.7761}

Created by Mathematica  (October 5, 2004)