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final correction on slides
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S1M0N38 committed Dec 21, 2020
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2 changes: 1 addition & 1 deletion slides/canonical-variables-definition.tex
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\begin{frame}{Motivation behind the definition of canonical variables}
\begin{alertblock}{}
In order to translating Lagrangian formalism in the Hamiltonian one, we
In order to translate Lagrangian formalism into the Hamiltonian one, we
need a \emph{map}~\footnote{
There is no need to map $q^{(6)}$ because it appears in Euler-Lagrange
equation as a simple derivation of terms depending on $q^{(5)}$. When
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11 changes: 5 additions & 6 deletions slides/constraints.tex
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\begin{frame}{Constraints classification}
\begin{alertblock}{Second classification}
\begin{itemize}
\item \emph{Primary constraints}: holds independently from the equations
of motion.
\item \emph{Primary constraints}: are the original constraints.
\begin{equation*} \label{eq:constraint}
\phi_1(Q, P) = 0
\end{equation*}
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\begin{frame}{Constrained Hamiltonians}
\begin{alertblock}{Introducing m-constraints in n-th order Hamiltonian}
\end{alertblock}
Constraints can be imposed in the Hamiltonian with the usage of
Constraints can be imposed on the Hamiltonian using
auxiliary variables $\lambda_i$ in the corresponding Lagrangian
\begin{equation*}
L = L(q, \dot{q}, \ddot{q}, \ldots, q^{(n)},
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\frac{\partial L}{\partial \lambda_i} = 0 \quad i=1, 2, \ldots, m
\end{equation*}

Canonical coordinates has to be chosen also for $\lambda_i$
Canonical coordinates have to be chosen also for $\lambda_i$
\begin{equation*} \label{eq:def_canonical_coordinates_lambda}
\Lambda_{i}:= \lambda_{i}
\quad \leftrightarrow \quad
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different number of secondary constraints can be found using the consistency
relations.

Finally, constraints relation can be organize as follows
Finally, constraints relations can be organized as follows
\begin{equation*}
\begin{cases}
\Lambda_i =\ f_i(Q_1, \ldots, Q_n, P_n) \\
\Pi_i =\ 0
\end{cases}
\qquad i = 1, 2, \ldots, m
\end{equation*}
and substitute in $\tilde{H}$ obtaining the \emph{constrained
and substituted into $\tilde{H}$ obtaining the \emph{constrained
Hamiltonian}
\begin{equation*}
H =\ P_n h + P_{n-1} Q_n + \cdots + P_1 Q_2
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2 changes: 1 addition & 1 deletion slides/first-order-vs-second-order-system.tex
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\begin{frame}{First order vs Second order Lagrangian}
We would like to find the differences between systems that can be
describe by these two Lagrangians:
described by these two Lagrangians:
\vspace{0.5em}
\begin{columns}
\begin{column}{0.4\textwidth}
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2 changes: 1 addition & 1 deletion slides/introduction.tex
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\begin{frame}{Why study HD systems?}
\begin{alertblock}{QFT + GR = Theory of everything}
\vspace{0.5em}
This is what string theory try to achieve but at the moment there are
This is what string theory tries to achieve but at the moment there are
no known doable experiments to corroborate it.
\end{alertblock}
So other paths may be explored in order to formulate a Theory of everything.
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2 changes: 1 addition & 1 deletion slides/lagrangian-and-hamiltonian-formalism.tex
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\begin{enumerate}
\begin{frame}{Hamiltonian formalism}
\begin{alertblock}{From Lagrange to Hamilton in 3 step}
\begin{alertblock}{From Lagrange to Hamilton in 3 steps}
\vspace{0.5em}
\item Define i-th \emph{canonical coordinates as} $(i = 1, \ldots, n)$
\begin{equation*} \label{eq:def_canonical_coordinates}
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14 changes: 7 additions & 7 deletions slides/linear-ostrogradskian-instability.tex
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\begin{frame}{Linear Ostrogradskian instability}
\begin{alertblock}{$H_2$ system isolated}
\vspace{0.5em}
If the energy is conserve even though the spectra is not bounded the
energy stay constant.
If the energy is conserved even though the spectra is not bounded the
energy stays constant.
\end{alertblock}
\vspace{2.0em}
\begin{alertblock}{$H_2$ interacting with $H_1$}
\vspace{0.5em}
$H_2$ system try to reach the minimum of the Hamiltonian $H_2$ by giving
$H_2$ system tries to reach the minimum of the Hamiltonian $H_2$ by giving
energy to $H_1$ system. This is behaviour goes on endlessly. This is the
so called \alert{Linear Ostrogradskian instability}~\cite{Kallosh08,
Eliezer89}.
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\end{frame}

\begin{frame}{Curing linear Ostrogradskian instability with constraints}
As shown in~\cite{Chen13} linear Ostrogradskian instability can be cured by
imposition of constrains on the system. This can happen when the constrained
As shown in~\cite{Chen13} the linear Ostrogradskian instability can be cured
by imposition of constrains on the system. This means that the constrained
Hamiltonian lives in phase space with lower dimensionality than the original
phase space.\\\vspace{0.3em}
Constraints have been introduced in the Lagrangian using auxiliary variables
$\lambda$, then they have been studied using the Dirac formalism for
Constraints may be introduced in the Lagrangian using auxiliary variables
$\lambda$, then they can be studied using the Dirac formalism for
constraints.\vspace{0.7em}

\begin{block}{Example: classical Pais-Uhlenbeck oscillator}
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