input
output
Illustration of a neural network equivariant to rotations in 3D
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Data-Augmentation
Equivariance
Fluid dynamics
Mechanics
Electrodynamics
Standard Model
Rotation
Translation
Boosts
(Galilean or Lorentz)
Time
translation
\(f:\) positions \(\to\) forces
\(f:\) positions \(\to\) Hamiltonian
Protein Folding
EquiFold Jae Hyeon Lee et al.
Protein Docking
DIFFDOCK Gabriele Corso et al.
Molecular Dynamics
Allegro A. Musaelian et al.
Open Catalyst Project.
Solid State Physics
Prediction of Phonon Density Z. Chen et al.
Molecular Electron Densities
Cracking the Quantum Scaling Limit with Machine Learned Electron Densities J. Rackers
Cosmology, Medical Images and others
44M atoms while taking advantage of up to 5120 GPUs
Albert Musaelian
(Nequip: Simon Batzner et al. 2021)
max L of the messages
Error
Trainset size
Invariant features
(Nequip: Simon Batzner et al. 2021)
Equivariant features
Error
Trainset size
Invariant features
"what are the operations"
"how they compose"
"what are the operations"
"how they compose"
"vector spaces on which the action of the group is defined"
"what are the operations"
"how they compose"
rotations, parity
scalars, vectors, pseudovectors, ...
"vector spaces on which the action of the group is defined"
Group \(G\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
Representation \(D(g, x)\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
Representation \(D(g, x)\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
Representation \(D(g, x)\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
Representation \(D(g, x)\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
Representation \(D(g, x)\)
Equivalent notation \(D(g) x\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Group \(G\)
Representation \(D(g, x)\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Equivalent notation \(D(g) x\)
Group \(G\)
Representation \(D(g, x)\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Equivalent notation \(D(g) x\)
Group \(G\)
Representation \(D(g, x)\)
"what are the operations" "how they compose"
"vector spaces on which the action of the group is defined"
Equivalent notation \(D(g) x\)
Group \(G\)
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
Representations are like data types
It tells you how to interpret the data with respect to the group action
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
3 scalars (3x0e)
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
Knowing that \(a_1, a_2, a_3\) are scalars tells you that they are not affected by a rotation of your system
Representations are like data types
It tells you how to interpret the data with respect to the group action
3 scalars (3x0e)
a vector (1o)
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
Representations are like data types
It tells you how to interpret the data with respect to the group action
3 scalars (3x0e)
a vector (1o)
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
If the system is rotated, the 3 components of the vector change together!
Representations are like data types
It tells you how to interpret the data with respect to the group action
3 scalars (3x0e)
a vector (1o)
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
a vector (1o)
The two vectors transforms independently
Representations are like data types
It tells you how to interpret the data with respect to the group action
3 scalars (3x0e)
a vector (1o)
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
a vector (1o)
system rotated by \(g\)
\(\begin{bmatrix} a'^1\\a'^2\\a'^3\\a'^4\\a'^5\\a'^6\\a'^7\\a'^8\\a'^9\end{bmatrix}=D(g)\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\)
Representations are like data types
It tells you how to interpret the data with respect to the group action
3 scalars
a vector
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
a vector
system rotated by \(g\)
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\)
Representations are like data types
It tells you how to interpret the data with respect to the group action
\(\begin{bmatrix} 1&&&&&&&&&&\\&1&&&&&&&\\&&1&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\end{bmatrix}\)
\(\begin{bmatrix}&&\\&R\\&&\end{bmatrix}\)
\(\begin{bmatrix}&&\\&R\\&&\end{bmatrix}\)
\(\begin{bmatrix} a'^1\\a'^2\\a'^3\\a'^4\\a'^5\\a'^6\\a'^7\\a'^8\\a'^9\end{bmatrix}=\)
3 scalars
a vector
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
a vector
system rotated by \(g\)
Representations are like data types
It tells you how to interpret the data with respect to the group action
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\)
\(\begin{bmatrix} 1&&&&&&&&&&\\&1&&&&&&&\\&&1&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\end{bmatrix}\)
\(\begin{bmatrix}&&\\&R\\&&\end{bmatrix}\)
\(\begin{bmatrix}&&\\&R\\&&\end{bmatrix}\)
\(\begin{bmatrix} a'^1\\a'^2\\a'^3\\a'^4\\a'^5\\a'^6\\a'^7\\a'^8\\a'^9\end{bmatrix}=\)
3 scalars
a vector
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\in \mathbb{R}^9\)
a vector
system rotated by \(g\)
Representations are like data types
It tells you how to interpret the data with respect to the group action
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\)
\(\begin{bmatrix} 1&&&&&&&&&&\\&1&&&&&&&\\&&1&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\\&&&&&&&&\end{bmatrix}\)
\(\begin{bmatrix}&&\\&R\\&&\end{bmatrix}\)
\(\begin{bmatrix}&&\\&R\\&&\end{bmatrix}\)
\(\begin{bmatrix} a'^1\\a'^2\\a'^3\\a'^4\\a'^5\\a'^6\\a'^7\\a'^8\\a'^9\end{bmatrix}=\)
\(V\)
\(V'\)
\(V\)
\(V'\)
\(D(g)\)
\(D'(g)\)
\(V\)
\(V'\)
\(V\)
\(V'\)
\(D(g)\)
\(D'(g)\)
\(V\)
\(V'\)
\(f\)
\(V\)
\(V'\)
\(D(g)\)
\(D'(g)\)
\(V\)
\(V'\)
\(f\)
\(f\)
\(V\)
\(V'\)
\(D(g)\)
\(D'(g)\)
\(V\)
\(V'\)
\(f\)
\(f\)
\(f(D(g) x)\)
\(V\)
\(V'\)
\(D(g)\)
\(D'(g)\)
\(V\)
\(V'\)
\(f\)
\(f\)
\(f(D(g) x)\)
\(D'(g) f(x)\)
\(V\)
\(V'\)
\(D(g)\)
\(D'(g)\)
\(V\)
\(V'\)
\(f\)
\(f\)
\(f(D(g) x)\)
\(D'(g) f(x)\)
\(=\)
Fluid dynamics
Mechanics
Electrodynamics
Standard Model
Rotation
Translation
Boosts
(Galilean or Lorentz)
These models are defined as invariant lagrangians \(\mathcal L(\text{state})\)
\(\mathcal L(D(g, \text{state})) = \mathcal L(\text{state})\)
Time
translation
two equivariant functions
\(f: V_1 \rightarrow V_2\)
\(h: V_2 \rightarrow V_3\)
\(h\circ f\) is equivariant!
\( h(f(D_1(g) x)) = h(D_2(g) f(x)) = D_3(g) h(f(x)) \)
two equivariant functions
\(f: V_1 \rightarrow V_3\)
\(h: V_2 \rightarrow V_3\)
\(h + f\) is equivariant!
\( f(D_1(g) x) + h(D_2(g)x) = D_3(g) (f(x) + h(x)) \)
two equivariant functions
\(f: V_1 \rightarrow V_3\)
\(h: V_2 \rightarrow V_3\)
\(h + f\) is equivariant!
\( f(D_1(g) x) + h(D_2(g)x) = D_3(g) (f(x) + h(x)) \)
equivariant function: \(f: V_1 \rightarrow V_2\)
a scalar: \(\alpha \in \mathbb{R}\)
\(\alpha f\) is equivariant!
\( \alpha f(D_1(g) x) = D_2(g) \alpha f(x) \)
\(\begin{bmatrix} {\color{red} x_1}\\{\color{red} x_2}\\{\color{red} x_3}\end{bmatrix}\)
\(\begin{bmatrix} {\color{blue} y_1}\\{\color{blue} y_2}\\{\color{blue} y_3}\\{\color{blue} y_4}\\{\color{blue} y_5} \end{bmatrix}\)
transforming with \(D(g)\)
transforming with \(D'(g)\)
\(= \begin{bmatrix} x_1y_1 & x_1y_2 & x_1y_3 & x_1y_4 & x_1y_5 \\ x_2y_1 & x_2y_2 & x_2y_3 & x_2y_4 & x_2y_5 \\ x_3y_1 & x_3y_2 & x_3y_3 & x_3y_4 & x_3y_5 \end{bmatrix}\)
\(\otimes\)
\(= \begin{bmatrix}{\color{red} x_1} {\color{blue} y_1}&{\color{red} x_1} {\color{blue} y_2}&{\color{red} x_1} {\color{blue} y_3}&{\color{red} x_1} {\color{blue} y_4}&{\color{red} x_1} {\color{blue} y_5}\\{\color{red} x_2} {\color{blue} y_1}&{\color{red} x_2} {\color{blue} y_2}&{\color{red} x_2} {\color{blue} y_3}&{\color{red} x_2} {\color{blue} y_4}&{\color{red} x_2} {\color{blue} y_5}\\{\color{red} x_3} {\color{blue} y_1}&{\color{red} x_3} {\color{blue} y_2}&{\color{red} x_3} {\color{blue} y_3}&{\color{red} x_3} {\color{blue} y_4}&{\color{red} x_3} {\color{blue} y_5}\end{bmatrix}\)
transforms with \(D(g) \otimes D'(g)\) 👍
\(\dim( D \otimes D' ) = \dim( D ) \dim( D' )\) 👎
\(\begin{bmatrix} {\color{red} x_1}\\{\color{red} x_2}\\{\color{red} x_3}\end{bmatrix}\)
\(\begin{bmatrix} {\color{blue} y_1}\\{\color{blue} y_2}\\{\color{blue} y_3}\\{\color{blue} y_4}\\{\color{blue} y_5} \end{bmatrix}\)
\(D\) defined on \(V\)
is reducible if
\(\exists W \subset V\) \(W\neq0, V\)
such that
\(D|_W\) is a representation
\(\begin{bmatrix}{\color{red} x_1} {\color{blue} x_2}&{\color{red} x_1} {\color{blue} y_2}&{\color{red} x_1} {\color{blue} z_2}\\{\color{red} y_1} {\color{blue} x_2}&{\color{red} y_1} {\color{blue} y_2}&{\color{red} y_1} {\color{blue} z_2}\\{\color{red} z_1} {\color{blue} x_2}&{\color{red} z_1} {\color{blue} y_2}&{\color{red} z_1} {\color{blue} z_2}\end{bmatrix}\)
\(\begin{bmatrix} {\color{red} x_1}\\{\color{red} y_1}\\{\color{red} z_1}\end{bmatrix}\otimes\begin{bmatrix} {\color{blue} x_2}\\{\color{blue} y_2}\\{\color{blue} z_2}\end{bmatrix} = \)
\(D\) defined on \(V\)
is reducible if
\(\exists W \subset V\) \(W\neq0, V\)
such that
\(D|_W\) is a representation
\({\color{red}x_1}{\color{blue}x_2} + {\color{red}y_1}{\color{blue}y_2} + {\color{red}z_1} {\color{blue}z_2}\)
\(\begin{bmatrix}c ( {\color{red}x_1} {\color{blue}z_2} + {\color{red}z_1} {\color{blue}x_2} ) \\ c ( {\color{red}x_1} {\color{blue}y_2} + {\color{red}y_1} {\color{blue}x_2} ) \\ 2 {\color{red}y_1} {\color{blue}y_2} - {\color{red}x_1} {\color{blue}x_2} - {\color{red}z_1} {\color{blue}z_2} \\ c ( {\color{red}y_1} {\color{blue}z_2} + {\color{red}z_1} {\color{blue}y_2} ) \\ c ( {\color{red}z_1} {\color{blue}z_2} - {\color{red}x_1} {\color{blue}x_2} ) \\\end{bmatrix}\)
\(\begin{bmatrix}{\color{red}y_1}{\color{blue}z_2}-{\color{red}z_1} {\color{blue}y_2}\\ {\color{red}z_1}{\color{blue}x_2}-{\color{red}x_1}{\color{blue}z_2}\\ {\color{red}x_1}{\color{blue}y_2}-{\color{red}y_1}{\color{blue}x_2}\end{bmatrix}\)
\(\begin{bmatrix}{\color{red} x_1} {\color{blue} x_2}&{\color{red} x_1} {\color{blue} y_2}&{\color{red} x_1} {\color{blue} z_2}\\{\color{red} y_1} {\color{blue} x_2}&{\color{red} y_1} {\color{blue} y_2}&{\color{red} y_1} {\color{blue} z_2}\\{\color{red} z_1} {\color{blue} x_2}&{\color{red} z_1} {\color{blue} y_2}&{\color{red} z_1} {\color{blue} z_2}\end{bmatrix}\)
\(3\times3=1+3+5\)
\(D\) defined on \(V\)
is reducible if
\(\exists W \subset V\) \(W\neq0, V\)
such that
\(D|_W\) is a representation
\(D\) defined on \(V\)
is irreducible if
only for \(W = 0\) or \(W=V\)
\(D|_W\) is a representation
For the group of rotations (\(SO(3)\))
They are index by \(L=0, 1, 2, \dots\)
Of dimension \(d=2L+1\)
L=0 | d=1 | scalar |
L=1 | d=3 | vector |
L=2 | d=5 | |
... |
For the group of rotations + parity (\(O(3)\))
They are index by \(L=0, 1, 2, \dots\)
and \(p=\pm 1\)
Of dimension \(d=2L+1\)
Even: \(p=1\)
Odd: \(p=-1\)
L=0 | d=1 | scalar |
L=1 | d=3 | pseudo vector |
L=2 | d=5 | |
... |
L=0 | d=1 | pseudo scalar |
L=1 | d=3 | vector |
L=2 | d=5 | |
... |
\(L_1 \otimes L_2 = |L_1-L_2| \oplus \dots \oplus (L_1+L_2)\)
Tells you how to decompose the tensor product of two irreps into irreps
3 scalars
a vector
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\)
a vector
3 scalars
a vector
\(\begin{bmatrix} b^1\\b^2\\b^3\\b^4\\b^5\\b^6\\b^7\\b^8\\b^9\end{bmatrix}\)
a vector
Linear map
3 scalars
a vector
\(\begin{bmatrix} a^1\\a^2\\a^3\\a^4\\a^5\\a^6\\a^7\\a^8\\a^9\end{bmatrix}\)
a vector
3 scalars
a vector
\(\begin{bmatrix} b^1\\b^2\\b^3\\b^4\\b^5\\b^6\\b^7\\b^8\\b^9\end{bmatrix}\)
a vector
\(w_1\)
\(w_2\)
\(w_3\)
by Schur's lemma
Data-Efficiency
Protein Folding
Molecular Dynamics
Phonons
Quantum Physics
Docking