275
Question.
Are there generic characterizations for the w-limit of a positive semi orbit
( II(jt,.)n( 19))
and its dependence on jJ?
nEN
It should be noted that II(jJ,') induces a strongly monotone dynamical system. We
refer to [Hess/PohiCik (1993)], [PolaCik/Teresbik (1991)] and [Takac (1992)] for interesting contributions. It seems though that it will be difficult to state good additional
hypotheses, which would allow to employ the presently available theory in the context
of (7).
Question.
Do stable subharmonic orbits exist for (II(jJ,. )n( 19))
?
nEN
As of yet, all relevant examples in the literature utilize symmetries, something that is
not available here.
10. Quasiperiodic Forcing.
The Milankovitch theory tries to relate the glacial-interglacial cycle to changes in
the earth's orbit around the sun.
Firstly, there is the variation in the excentricity, which has a cycle of about 110 thousand years. Secondly, the obliquity, i.e. the angle between the rotational axis of the
earth and the plane determined by the earth's orbit, varies with a period of about 40
thousand years. Thirdly, there is the motion of the perihelion, which is the point on the
earth's orbit that assumes the shortest distance to the sun. This precession causes a
change in the time of the year, when the equinoxes occur. It seems to be quasiperiodic
with periods of about 18 and 23 thousand years.
Though the second and third effect do not affect the global yearly average of the incoming radiation fluxes, they cause of course a cyclic variation of Q(', ;r) and have therefore
accounted for. Superimposing these effects and the seasonal cycle proVIdes a function Q,
which is most likely quasiperiodic in time, but not periodic. Consequently, one should
consider (7) under the weaker hypothesis that Q(-, x) is only almost periodic for x E M.
The first question one should address in this COlltCxt is whether OIlC ran expert almost
periodic responses, i.e.
Question.
Question.
Are there generic characterizations for the w-limit of a positive semi orbit
( II(jt,.)n( 19))
and its dependence on jJ?
nEN
It should be noted that II(jJ,') induces a strongly monotone dynamical system. We
refer to [Hess/PohiCik (1993)], [PolaCik/Teresbik (1991)] and [Takac (1992)] for interesting contributions. It seems though that it will be difficult to state good additional
hypotheses, which would allow to employ the presently available theory in the context
of (7).
Question.
Do stable subharmonic orbits exist for (II(jJ,. )n( 19))
?
nEN
As of yet, all relevant examples in the literature utilize symmetries, something that is
not available here.
10. Quasiperiodic Forcing.
The Milankovitch theory tries to relate the glacial-interglacial cycle to changes in
the earth's orbit around the sun.
Firstly, there is the variation in the excentricity, which has a cycle of about 110 thousand years. Secondly, the obliquity, i.e. the angle between the rotational axis of the
earth and the plane determined by the earth's orbit, varies with a period of about 40
thousand years. Thirdly, there is the motion of the perihelion, which is the point on the
earth's orbit that assumes the shortest distance to the sun. This precession causes a
change in the time of the year, when the equinoxes occur. It seems to be quasiperiodic
with periods of about 18 and 23 thousand years.
Though the second and third effect do not affect the global yearly average of the incoming radiation fluxes, they cause of course a cyclic variation of Q(', ;r) and have therefore
accounted for. Superimposing these effects and the seasonal cycle proVIdes a function Q,
which is most likely quasiperiodic in time, but not periodic. Consequently, one should
consider (7) under the weaker hypothesis that Q(-, x) is only almost periodic for x E M.
The first question one should address in this COlltCxt is whether OIlC ran expert almost
periodic responses, i.e.
Question.