Ricard Puig
@pvricard.bsky.social
Ph.D. candidate in physics at EPFL.
Working on Quantum Computing and Quantum Metrology.
Working on Quantum Computing and Quantum Metrology.
Thanks to all my collaborators Hela Mhiri, Sacha Lerch, @quantummanuel.bsky.social, @thipchotibut.bsky.social, Supanut Thanasilp, @qzoeholmes.bsky.social
February 13, 2025 at 2:49 PM
Thanks to all my collaborators Hela Mhiri, Sacha Lerch, @quantummanuel.bsky.social, @thipchotibut.bsky.social, Supanut Thanasilp, @qzoeholmes.bsky.social
We therefore conclude that while warm-starting strategies offer some hope for sidestepping the barren plateau phenomenon, for this hope to be realized, we will likely need increasingly clever initialization strategies.
February 13, 2025 at 2:49 PM
We therefore conclude that while warm-starting strategies offer some hope for sidestepping the barren plateau phenomenon, for this hope to be realized, we will likely need increasingly clever initialization strategies.
Finally, we show that for some circuits, having BP when looking at the whole landscape also means having BP in some of the order-1 regions. This, combined with our numerical analysis, suggests that warm-starting strategies will need to increase precision as the number of qubits increases.
February 13, 2025 at 2:49 PM
Finally, we show that for some circuits, having BP when looking at the whole landscape also means having BP in some of the order-1 regions. This, combined with our numerical analysis, suggests that warm-starting strategies will need to increase precision as the number of qubits increases.
We also reproduce results for previously studied circuits, particularly around the identity, for HVA, HEA, and tensor product ansatz. We use these results to analyze the effect of global/local observables and the impact of correlating parameters.
February 13, 2025 at 2:49 PM
We also reproduce results for previously studied circuits, particularly around the identity, for HVA, HEA, and tensor product ansatz. We use these results to analyze the effect of global/local observables and the impact of correlating parameters.
We use this bound to study different circuits and points on the landscape. In particular, we present a corollary that characterizes the size of the region around the minima. We also focus on studying the region around zero for time-correlated circuits, such as the correlated UCC or HVA circuits.
February 13, 2025 at 2:49 PM
We use this bound to study different circuits and points on the landscape. In particular, we present a corollary that characterizes the size of the region around the minima. We also focus on studying the region around zero for time-correlated circuits, such as the correlated UCC or HVA circuits.
We analytically prove a generic lower bound on the variance of a loss function. It can be applied around any point on the landscape and for a wide range of circuits. Around any point with substantial curvature, we can prove that there exists a substantial region with (non-exp small) gradients.
February 13, 2025 at 2:49 PM
We analytically prove a generic lower bound on the variance of a loss function. It can be applied around any point on the landscape and for a wide range of circuits. Around any point with substantial curvature, we can prove that there exists a substantial region with (non-exp small) gradients.
Special thanks to my co-authors Marc Drudis, Supanut Thanasilp and @qzoeholmes.bsky.social
January 24, 2025 at 11:37 AM
Special thanks to my co-authors Marc Drudis, Supanut Thanasilp and @qzoeholmes.bsky.social
However this does not mean that it is not possible to train. To do so the ‘only thing’ we require is a path with substantial gradients. These fertile valleys between barren regions can theoretically exist, but to what extent is unknown. We provide a toy example of this.
January 24, 2025 at 11:37 AM
However this does not mean that it is not possible to train. To do so the ‘only thing’ we require is a path with substantial gradients. These fertile valleys between barren regions can theoretically exist, but to what extent is unknown. We provide a toy example of this.
A final limitation of our analysis is that the adiabatic minimum need not be the global minimum of the loss. It is possible for the best minimum to jump from the initialization region to another. We show an example in which this seems to happen.
January 24, 2025 at 11:37 AM
A final limitation of our analysis is that the adiabatic minimum need not be the global minimum of the loss. It is possible for the best minimum to jump from the initialization region to another. We show an example in which this seems to happen.
An adiabatic minimum is the one that a marble dropped in the initial minima would follow if the landscape were slowly modified with time. We show that the scheme will converge to this minimum if the time step is small enough for the minimum to be within the above region.
January 24, 2025 at 11:37 AM
An adiabatic minimum is the one that a marble dropped in the initial minima would follow if the landscape were slowly modified with time. We show that the scheme will converge to this minimum if the time step is small enough for the minimum to be within the above region.
Focusing on an iterative variational method for quantum dynamics as an ideal playground for studying warm starts, we can analytically guarantee substantial gradients and approximate convexity around the initializations at each (small) time-step.
January 24, 2025 at 11:37 AM
Focusing on an iterative variational method for quantum dynamics as an ideal playground for studying warm starts, we can analytically guarantee substantial gradients and approximate convexity around the initializations at each (small) time-step.
Barren plateaus are fundamentally a statement about the landscape "on average". However, there may be small regions with substantial gradients and good solutions. This has motivated the study of warm starts whereby the algorithm is cleverly initialized closer to a minimum.
January 24, 2025 at 11:37 AM
Barren plateaus are fundamentally a statement about the landscape "on average". However, there may be small regions with substantial gradients and good solutions. This has motivated the study of warm starts whereby the algorithm is cleverly initialized closer to a minimum.
Is a barren plateau landscape trainable? If we start close to the actual solution, then probably yes!?
Here we study variational quantum simulation to explore whether warm starts can be a possible solution to exponential concentration
Here we study variational quantum simulation to explore whether warm starts can be a possible solution to exponential concentration
January 24, 2025 at 11:37 AM
Is a barren plateau landscape trainable? If we start close to the actual solution, then probably yes!?
Here we study variational quantum simulation to explore whether warm starts can be a possible solution to exponential concentration
Here we study variational quantum simulation to explore whether warm starts can be a possible solution to exponential concentration
Thanks to all my collaborators for making this possible Pavel Sekatski, Paolo Andrea Erdman, Paolo Abiuso, John Calsamiglia ( @giq-bcn.bsky.social ), and Martí Perarnau-Llobet
December 5, 2024 at 9:36 AM
Thanks to all my collaborators for making this possible Pavel Sekatski, Paolo Andrea Erdman, Paolo Abiuso, John Calsamiglia ( @giq-bcn.bsky.social ), and Martí Perarnau-Llobet
With this work we try to provide new insights into the potential and limits of many-body metrology.
December 5, 2024 at 9:36 AM
With this work we try to provide new insights into the potential and limits of many-body metrology.
We also analyze the transient regime from the dynamical metrology to the steady – state via different processes, and characterize tradeoffs between equilibration times and measurement precision.
December 5, 2024 at 9:36 AM
We also analyze the transient regime from the dynamical metrology to the steady – state via different processes, and characterize tradeoffs between equilibration times and measurement precision.
Starting from a product state, we present bounds for the Quantum Fisher Information and find physically relevant interactions that approach such bounds.
We study this for the dynamical regime and for the Gibbs and time-averaged dephased state.
We study this for the dynamical regime and for the Gibbs and time-averaged dephased state.
December 5, 2024 at 9:36 AM
Starting from a product state, we present bounds for the Quantum Fisher Information and find physically relevant interactions that approach such bounds.
We study this for the dynamical regime and for the Gibbs and time-averaged dephased state.
We study this for the dynamical regime and for the Gibbs and time-averaged dephased state.
Would really appreciate it! Thanks.
December 1, 2024 at 11:58 AM
Would really appreciate it! Thanks.
Hey!! Could you add me please?
November 26, 2024 at 9:45 AM
Hey!! Could you add me please?