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add hypernova multifolding slides, udpate notes_hypernova

- add hypernova multifolding slides
- add hypernova details with colors on how the multifolding terms relate for LCCCS & CCCS
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arnaucube 10 months ago
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\documentclass{beamer}
\mode<presentation>
{
\usetheme{Frankfurt}
\usecolortheme{dove} %% grey scale
\useinnertheme{circles}
\setbeamercovered{transparent}
}
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colorlinks,
citecolor=black,
filecolor=black,
linkcolor=black,
urlcolor=blue
}
\usepackage{graphicx}
\usepackage{pgf-umlsd} % diagrams
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\setbeamertemplate{itemize items}{$\circ$}
\beamertemplatenavigationsymbolsempty %% no navigation bar
\setbeamertemplate{footline}{\hspace*{.1cm}\scriptsize{
\hspace*{50pt} \hfill\insertframenumber/\inserttotalframenumber\hspace*{.1cm}\vspace*{.1cm}}}
\setbeamertemplate{caption}[numbered]
\setbeamerfont{caption}{size=\tiny}
% message between threads. From https://tex.stackexchange.com/a/174765
% Example:
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%Information to be included in the title page:
\title{HyperNova's multifolding overview}
\author{}
\date{\scriptsize{2023-06-22\\\href{https://0xparc.org}{0xPARC} Novi team}}
\begin{document}
\frame{\titlepage}
\section[Overview]{Overview}
\begin{frame}{Multifolding - Overview}
\begin{tiny}
\begin{enumerate}
\item[1.] $V \rightarrow P: \gamma \in^R \mathbb{F},~ \beta \in^R \mathbb{F}^s$
\item[2.] $V: r_x' \in^R \mathbb{F}^s$
\item[3.] $V \leftrightarrow P$: sum-check protocol:
$c \leftarrow \langle P, V(r_x') \rangle (g, s, d+1, \underbrace{\sum_{j \in [t]} \gamma^j \cdot v_j}_\text{T})$, where:
\begin{align*}
g(x) &:= \underbrace{\left( \sum_{j \in [t]} \gamma^j \cdot L_j(x) \right)}_\text{LCCCS check} + \underbrace{\gamma^{t+1} \cdot Q(x)}_\text{CCCS check}\\
L_j(x) &:= \widetilde{eq}(r_x, x) \cdot \left(
\underbrace{\sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_1(y)}_\text{LCCCS check}
\right)\\
Q(x) := &\widetilde{eq}(\beta, x) \cdot \left(
\underbrace{ \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_2(y) \right) }_\text{CCCS check}
\right)
\end{align*}
\end{enumerate}
\end{tiny}
\end{frame}
\begin{frame}{Multifolding - Overview}
\begin{tiny}
\begin{enumerate}
\item[4.] $P \rightarrow V$: $\left( (\sigma_1, \ldots, \sigma_t), (\theta_1, \ldots, \theta_t) \right)$, where $\forall j \in [t]$,
$$\sigma_j = \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \widetilde{z}_1(y)$$
$$\theta_j = \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \widetilde{z}_2(y)$$
\item[5.] V: $e_1 \leftarrow \widetilde{eq}(r_x, r_x')$, $e_2 \leftarrow \widetilde{eq}(\beta, r_x')$\\
check:
$$c = \left(\sum_{j \in [t]} \gamma^j \cdot e_1 \cdot \sigma_j \right) + \gamma^{t+1} \cdot e_2 \cdot \left( \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \theta_j \right)$$
\item[6.] $V \rightarrow P: \rho \in^R \mathbb{F}$
\item[7.] $V, P$: output the folded LCCCS instance $(C', u', \mathsf{x}', r_x', v_1', \ldots, v_t')$, where $\forall i \in [t]$:
\begin{align*}
C' &\leftarrow C_1 + \rho \cdot C_2\\
u' &\leftarrow u + \rho \cdot 1\\
\mathsf{x}' &\leftarrow \mathsf{x}_1 + \rho \cdot \mathsf{x}_2\\
v_i' &\leftarrow \sigma_i + \rho \cdot \theta_i
\end{align*}
\item[8.] $P$: output folded witness and the folded $r_w'$:
\begin{align*}
\widetilde{w}' &\leftarrow \widetilde{w}_1 + \rho \cdot \widetilde{w}_2\\
r_w' &\leftarrow r_{w_1} + \rho \cdot r_{w_2}
\end{align*}
\end{enumerate}
\end{tiny}
\end{frame}
\begin{frame}{Multifolding - Overview}
\begin{tiny}
\begin{center}
\begin{sequencediagram}
\newinst[1]{p}{Prover}
\newinst[3]{v}{Verifier}
\bloodymess[1]{v}{$\gamma,~\beta,~r_x'$}{p}{L}{
\shortstack{
$\gamma \in \mathbb{F},~ \beta \in \mathbb{F}^s$\\
$r_x' \in \mathbb{F}^s$
}
}{}
\bloodymess[1]{p}{$c,~ \pi_{SC}$}{v}{R}{sum-check prove}{sum-check verify}
\bloodymess[1]{p}{$\{\sigma_j\},~\{\theta_j\}$}{v}{R}{compute $\{\sigma_j\}, \{\theta_j\}~ \forall j \in [t]$}{verify $c$ with $\{\sigma_j\}, \{\theta_j\}$ relation}
\bloodymess[1]{v}{$\rho$}{p}{L}{$\rho \in^R \mathbb{F}$}{}
\callself[0]{p}{fold LCCCS instance}{p}
\prelevel
\callself[0]{v}{fold LCCCS instance}{v}
\callself[0]{p}{fold $\widetilde{w}, r_w$}{p}
\end{sequencediagram}
\end{center}
\end{tiny}
\end{frame}
\section[Checks]{Checks}
\begin{tiny}
\begin{frame}{LCCCS checks}
$$
\color{gray}{g(x) :=}
\color{black}{\underbrace{\left( \sum_{j \in [t]} \gamma^j \cdot L_j(x) \right)}_\text{LCCCS} }
\color{gray}{+ \gamma^{t+1} \cdot Q(x)}
$$
$$
L_j(x) := \widetilde{eq}(r_x, x) \cdot \left(
\underbrace{\sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_1(y)}_\text{LCCCS check}
\right)
$$
Notice that, $v_j$ from LCCCS relation check
\begin{align*}
v_j &= \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(r_x, y) \cdot \widetilde{z}_1(y)\\
&= \sum_{x \in \{0,1\}^s}
\widetilde{eq}(r_x, x) \cdot \left( \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_1(y) \right)\\
&= \sum_{x \in \{0,1\}^s} L_j(x)
\end{align*}
\end{frame}
\begin{frame}{CCCS checks}
$$
\color{gray}{g(x) := \left( \sum_{j \in [t]} \gamma^j \cdot L_j(x) \right) +}
\color{black}{\underbrace{\gamma^{t+1} \cdot Q(x)}_\text{CCCS}}
$$
$$Q(x) := \widetilde{eq}(\beta, x) \cdot \left(
\underbrace{ \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_2(y) \right) }_\text{CCCS check}
\right)$$
Recall that Spartan's $\widetilde{F}_{io}(x)$ here is $q(x)$, so we're doing the same Spartan check:
$$
0 =G(\beta) = \sum_{x \in \{0,1\}^s} Q(x) = \sum_{x \in \{0,1\}^s} eq(\beta, x) \cdot q(x)$$
$$= \sum_{x \in \{0,1\}^s}
\underbrace{\widetilde{eq}(\beta , x) \cdot
\overbrace{
\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_2(y) \right)
}^{q(x)}
}_{Q(x)}
$$
\end{frame}
\begin{frame}{Verifier checks}
\textcolor{gray}{
Recall:
$$g(x) := \left( \sum_{j \in [t]} \gamma^j \cdot L_j(x) \right) + \gamma^{t+1} \cdot Q(x)$$
$$c = \left(\sum_{j \in [t]} \gamma^j \cdot e_1 \cdot \sigma_j \right) + \gamma^{t+1} \cdot e_2 \cdot \left( \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \theta_j \right)$$
}
We can see now that V's check in step 5,
\begin{align*}
c &=
\left( \sum_{j \in [t]} \gamma^j \cdot \overbrace{e_1 \cdot \sigma_j}^{L_j(r_x')} \right) + \gamma^{t+1} \cdot \overbrace{e_2 \cdot \sum_{i \in [q]} c_i \prod_{j \in S_i} \theta_j}^{Q(x)}\\
&= \left( \sum_{j \in [t]} \gamma^j \cdot L_j(r_x') \right) + \gamma^{t+1} \cdot Q(r_x')\\
&= g(r_x')
\end{align*}
where $e_1 = \widetilde{eq}(r_x, r_x')$, $e_2=\widetilde{eq}(\beta, r_x')$.
\end{frame}
\end{tiny}
\section[Multiple instances]{Multiple instances}
\begin{footnotesize}
\begin{frame}{Multifolding multiple instances}
Hypernova paper: $\mu=1, \nu=1$ \emph{(ie. 1 LCCCS instance and 1 CCCS instance)}
\vspace{1cm}
In next slides
\begin{itemize}
\item example with: $\color{orange}{LCCCS: \mu = 2},~ \color{blue}{CCCS: \nu = 2}$
\item generalized equations for $\mu,~\nu$
\end{itemize}
Let $z_1,~ \color{orange}{z_2}$ be the two LCCCS instances, and $z_3,~ \color{blue}{z_4}$ be the two CCCS instances
\end{frame}
\end{footnotesize}
\begin{tiny}
\begin{frame}
In \emph{step 3},
\begin{align*}
g(x) &:= \left( \sum_{j \in [t]} \gamma^j \cdot L_{1,j}(x) + \textcolor{orange}{\gamma^{t+j} \cdot L_{2,j}(x)} \right)
+ \gamma^{2t+1} \cdot Q_1(x) + \textcolor{cyan}{\gamma^{2t+2} \cdot Q_2(x)} \\
&L_{1,j}(x) := \widetilde{eq}(r_{1,x}, x) \cdot \left(
\sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_1(y)
\right)\\
&\textcolor{orange}{L_{2,j}(x)} := \widetilde{eq}(\textcolor{orange}{r_{2,x}}, x) \cdot \left(
\sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \textcolor{orange}{\widetilde{z}_2(y)}
\right)\\
&Q_1(x) := \widetilde{eq}(\beta, x) \cdot \left(
\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_3(y) \right)\right)\\
&\textcolor{cyan}{Q_2(x)} := \widetilde{eq}(\textcolor{cyan}{\beta}, x) \cdot \left(
\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \textcolor{cyan}{\widetilde{z}_4(y)} \right)\right)
\end{align*}
\framebox{\begin{minipage}{4.3 in}
A generic definition of $g(x)$ for $\mu>1~\nu>1$, would be
$$
g(x) := \left( \sum_{i \in [\mu]} \left( \sum_{j \in [t]} \gamma^{i \cdot t+j} \cdot L_{i,j}(x) \right) \right)
+ \left( \sum_{i \in [\nu]} \gamma^{\mu \cdot t + i} \cdot Q_i(x) \right)
$$
\end{minipage}}
Recall, the original $g(x)$ definition was
$$\textcolor{gray}{g(x) := \left( \sum_{j \in [t]} \gamma^j \cdot L_j(x) \right) + \gamma^{t+1} \cdot Q(x)}$$
\end{frame}
\begin{frame}
In \emph{step 4}, $P \rightarrow V$: $(\{\sigma_{1,j}\}, \textcolor{orange}{\{\sigma_{2,j}\}}, \{\theta_{1,j}\}, \textcolor{cyan}{\{\theta_{2,j}\}}),~ \text{where} ~\forall j \in [t]$,
$$\sigma_{1,j} = \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \widetilde{z}_1(y)$$
$$\textcolor{orange}{\sigma_{2,j}} = \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \textcolor{orange}{\widetilde{z}_2(y)}$$
$$\theta_{1,j} = \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \widetilde{z}_3(y)$$
$$\textcolor{cyan}{\theta_{2,j}} = \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \textcolor{cyan}{\widetilde{z}_4(y)}$$
\framebox{\begin{minipage}{4.3 in}
so in a generic way,\\
$P \rightarrow V$:
$(\{\sigma_{i,j}\}, \{\theta_{k,j}\}),~ \text{where} ~\forall~ j \in [t],~ \forall~ i \in [\mu],~ \forall~ k \in [\nu]$
where
$$\sigma_{i,j} = \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \widetilde{z}_i(y)$$
$$\theta_{k,j} = \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(r_x', y) \cdot \widetilde{z}_{\mu+k}(y)$$
\end{minipage}}
\end{frame}
\begin{frame}
And in \emph{step 5}, $V$ checks
\begin{align*}
c &= \left(\sum_{j \in [t]} \gamma^j \cdot e_1 \cdot \sigma_{1,j}
~\textcolor{orange}{+ \gamma^{t+j} \cdot e_2 \cdot \sigma_{2,j}}\right)
+ \gamma^{2t+1} \cdot e_3 \cdot \left( \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \theta_j \right)
+ \textcolor{cyan}{\gamma^{2t+2} \cdot e_4 \cdot \left( \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \theta_j \right)}
\end{align*}
where
$e_1 \leftarrow \widetilde{eq}(r_{1,x}, r_x'),~ e_2 \leftarrow \widetilde{eq}(r_{2,x}, r_x')$, $e_3, e_4 \leftarrow \widetilde{eq}(\beta, r_x')$.
\vspace{0.5cm}
\framebox{\begin{minipage}{4.3 in}
A generic definition of the check would be
$$
c = \sum_{i \in [\mu]} \left(\sum_{j \in [t]} \gamma^{i \cdot t + j} \cdot e_i \cdot \sigma_{i,j} \right) \\
+ \sum_{k \in [\nu]} \gamma^{\mu \cdot t+k} \cdot e_k \cdot \left( \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \theta_{k,j} \right)
$$
\end{minipage}}
where the original check was\\
$\textcolor{gray}{c = \left(\sum_{j \in [t]} \gamma^j \cdot e_1 \cdot \sigma_j \right) + \gamma^{t+1} \cdot e_2 \cdot \left( \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \theta_j \right)}$
\end{frame}
\begin{frame}
And for the \emph{step 7},
\begin{align*}
C' &\leftarrow C_1 + \rho \cdot C_2 + \rho^2 C_3 + \rho^3 C_4 + \ldots = \sum_{i \in [\mu + \nu]} \rho^i \cdot C_i \\
u' &\leftarrow \sum_{i \in [\mu]} \rho^i \cdot u_i + \sum_{i \in [\nu]} \rho^{\mu + i-1} \cdot 1\\
\mathsf{x}' &\leftarrow \sum_{i \in [\mu+\nu]} \rho^i \cdot \mathsf{x}_i\\
v_i' &\leftarrow \sum_{i \in [\mu]} \rho^i \cdot \sigma_i + \sum_{i \in [\nu]} \rho^{\mu + i-1} \cdot \theta_i\\
\end{align*}
and \emph{step 8},
\begin{align*}
\widetilde{w}' &\leftarrow \sum_{i \in [\mu+\nu]} \rho^i\cdot \widetilde{w}_i\\
r_w' &\leftarrow \sum_{i \in [\mu+\nu]} \rho^i \cdot r_{w_i}\\
\end{align*}
\end{frame}
\end{tiny}
\section[Wrappup]{Wrappup}
\begin{frame}
\frametitle{Wrappup}
\begin{itemize}
\item HyperNova: \href{https://eprint.iacr.org/2023/573}{https://eprint.iacr.org/2023/573}
\item multifolding PoC on arkworks: \href{https://github.com/privacy-scaling-explorations/multifolding-poc}{github.com/privacy-scaling-explorations/multifolding-poc}
\end{itemize}
\vspace{2cm}
\tiny{
$$\text{2023-06-22}$$
$$\text{\href{https://0xparc.org}{0xPARC} Novi team}$$
}
\end{frame}
\end{document}

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notes_hypernova.tex

@ -206,40 +206,66 @@ Multifolding flow:
\vspace{1cm}
Recall that we are folding 2 instances:
\begin{itemize}
\item[] LCCCS: $(C, u, \textcolor{orange}{x_1}, \textcolor{magenta}{r_x}, \textcolor{orange}{v_1, \ldots, v_t})$
\item[] CCCS: $(C, \textcolor{cyan}{x_2})$
\end{itemize}
Now, to see the verifier check from step 5, observe that in LCCCS, since $\widetilde{w}$ satisfies,
\begin{align*}
v_j &= \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(r_x, y) \cdot \widetilde{z}_1(y)\\
&= \sum_{x \in \{0,1\}^s}
\underbrace{
\widetilde{eq}(r_x, x) \cdot \left( \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_1(y) \right)
}_{L_j(x)}\\
&= \sum_{x \in \{0,1\}^s} L_j(x)
\textcolor{orange}{L_j(x)} &:= \widetilde{eq}(\textcolor{magenta}{r_x}, x) \cdot \left(
\sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \textcolor{orange}{\widetilde{z}_1(y)}
\right)\\
&\textcolor{orange}{v_j}= \sum_{y\in \{0,1\}^{s'}} \widetilde{M}_j(\textcolor{magenta}{r_x}, y) \cdot \textcolor{orange}{\widetilde{z}_1(y)})\\
&~~=\sum_{x \in \{0,1\}^s} \widetilde{eq}(\textcolor{magenta}{r_x},y) \cdot (\sum_{y\in \{0,1\}^{s'}} \widetilde{M}_j(x,y)\cdot \textcolor{orange}{\widetilde{z}_1(y)})\\
&~~=\sum_{x \in \{0,1\}^s} \textcolor{orange}{L_j(x)}
\end{align*}
Observe also that in CCCS, since $\widetilde{w}$ satisfies,
$$
0=\underbrace{\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_2(y) \right)}_{q(x)}
$$
Observe also that in CCCS, since $\widetilde{w}$ satisfies,\\
we have that
$$
G(X) = \sum_{x \in \{0,1\}^s} eq(X, x) \cdot q(x)
G(X) = \sum_{x \in \{0,1\}^s} \widetilde{eq}(X, x) \cdot \textcolor{cyan}{q(x)}
$$
is multilinear, and can be seen as a Lagrange polynomial where coefficients are evaluations of $q(x)$ on the hypercube.
For an honest prover, all these coefficients are zero, thus $G(X)$ must necessarily be the zero polynomial. Thus $G(\beta)=0$ for $\beta \in^R \mathbb{F}^s$.
\begin{align*}
% 0&=\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(\beta, y) \cdot \widetilde{z}_2(y) \right)\\
0&=G(\beta) = \sum_{x \in \{0,1\}^s} eq(\beta, x) \cdot q(x)\\
&= \sum_{x \in \{0,1\}^s}
\underbrace{\widetilde{eq}(\beta , x) \cdot
\overbrace{
\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_2(y) \right)
}^{q(x)}
}_{Q(x)}\\
&= \sum_{x \in \{0,1\}^s} Q(x)
\textcolor{cyan}{Q(x)} := &\widetilde{eq}(\textcolor{magenta}{\beta}, x) \cdot \left(
\overbrace{ \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \textcolor{cyan}{\widetilde{z}_2(y)} \right)
}^\textcolor{cyan}{q(x)}
\right)\\
0= &\sum_{i=1}^q c_i \prod_{j\in S_i} \left( \sum_{y\in \{0,1\}^{s'}} \widetilde{M}_j(\textcolor{magenta}{\beta}, y) \cdot \textcolor{cyan}{\widetilde{z}_2(y)}\right)\\
=&\sum_{x \in \{0,1\}^s} \widetilde{eq}(\textcolor{magenta}{\beta}, x) \cdot \left( \sum_{i=1}^q c_i \prod_{j\in S_i} ( \sum_{y\in \{0,1\}^{s'}} \widetilde{M}_j(x, y) \cdot \textcolor{cyan}{\widetilde{z}_2(y)}) \right) \\
=&\sum_{x \in \{0,1\}^s} \textcolor{cyan}{Q(x)} = G(\textcolor{magenta}{\beta})
\end{align*}
%
For an honest prover, all these coefficients are zero, thus $G(X)$ must necessarily be the zero polynomial. Thus $G(\beta)=0$ for $\beta \in^R \mathbb{F}^s$.
\vspace{1cm}
We can now see that
$$\textcolor{orange}{\sigma_j} = \sum_{y \in \{0,1\}^{s'}} \widetilde{M}_j(\textcolor{pink}{r_x'}, y) \cdot \textcolor{orange}{\widetilde{z}_1(y)},
~~~\textcolor{cyan}{\theta_j} = \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(\textcolor{pink}{r_x'}, y) \cdot \textcolor{cyan}{\widetilde{z}_2(y)}$$
$$e_1 \leftarrow \widetilde{eq}(\textcolor{magenta}{r_x}, \textcolor{pink}{r_x'}),~ e_2 \leftarrow \widetilde{eq}(\textcolor{magenta}{\beta}, \textcolor{pink}{r_x'})$$
so the Verifier's check:
\begin{align*}
c &= \left(
\sum_{j \in [t]} \gamma^j \cdot \underbrace{e_1 \cdot \textcolor{orange}{\sigma_j} }_\textcolor{orange}{L_j}(\textcolor{pink}{r_x'})
\right)
+ \gamma^{t+1} \cdot
\underbrace{e_2 \cdot \left( \sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \textcolor{cyan}{\theta_j} \right) }_\textcolor{cyan}{Q}(\textcolor{pink}{r_x'})\\
&= \left( \sum_{j\in [t]} \gamma^j \cdot \textcolor{orange}{L_j}(\textcolor{pink}{r_x'}) \right) + \gamma^{t+1} \cdot \textcolor{cyan}{Q}(\textcolor{pink}{r_x'})\\
&= g(\textcolor{pink}{r_x'})
\end{align}
$$\textcolor{gray}{(Recall,~ g(x) := \left( \sum_{j \in [t]} \gamma^j \cdot L_j(x) \right) + \gamma^{t+1} \cdot Q(x))}$$
Outputed LCCCS: $(C', u', x', \textcolor{pink}{r_x'}, v_1', \ldots, v_t')$
\framebox{\begin{minipage}{4.3 in}
\begin{footnotesize}
@ -277,18 +303,6 @@ $$0 = \sum_{x \in \{0,1\}^s} Q(x) = \sum_{x \in \{0,1\}^s} \widetilde{eq}(\beta,
\vspace{1cm}
Comming back to HyperNova equations, we can now see that
\begin{align*}
c &= g(r_x')\\
&= \left( \sum_{j \in [t]} \gamma^j \cdot L_j(r_x') \right) + \gamma^{t+1} \cdot Q(r_x')\\
&= \left( \sum_{j \in [t]} \gamma^j \cdot \overbrace{e_1 \cdot \sigma_j}^{L_j(r_x')} \right) + \gamma^{t+1} \cdot \overbrace{e_2 \cdot \sum_{i \in [q]} c_i \prod_{j \in S_i} \theta_j}^{Q(x)}
\end{align*}
where $e_1 = \widetilde{eq}(r_x, r_x')$ and $e_2=\widetilde{eq}(\beta, r_x')$.
Which is the check that $V$ performs at step $5$.
\subsection{Multifolding for multiple instances}
The multifolding of multiple LCCCS \& CCCS instances is not shown in the HyperNova paper, but Srinath Setty gave an overview in the PSE HyperNova presentation. This section unfolds it.
@ -309,7 +323,7 @@ In \emph{step 3} of the multifolding with more than one LCCCS and more than one
\right)\\
&Q_1(x) := \widetilde{eq}(\beta, x) \cdot \left(
\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \widetilde{z}_3(y) \right)\right)\\
&\textcolor{cyan}{Q_2(x)} := \widetilde{eq}(\textcolor{cyan}{\beta'}, x) \cdot \left(
&\textcolor{cyan}{Q_2(x)} := \widetilde{eq}(\textcolor{cyan}{\beta}, x) \cdot \left(
\sum_{i=1}^q c_i \cdot \prod_{j \in S_i} \left( \sum_{y \in \{0, 1\}^{s'}} \widetilde{M}_j(x, y) \cdot \textcolor{cyan}{\widetilde{z}_4(y)} \right)\right)
\end{align*}

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