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Stefano Ciliberti

Publications and source records attributed to Stefano Ciliberti.

3 recordsLinked to original sources

Glasslike structure of globular proteins and the boson peak.

Vibrational spectra of proteins and topologically disordered solids display a common anomaly at low frequencies, known as boson peak. We show that such feature in globular proteins can be deciphered in terms of an energy landscape picture, as it is for glassy systems. Exploiting the tools of Euclidean random matrix theory, we clarify the physical origin of such anomaly in terms of a mechanical instability of the system. As a natural explanation, we argue that such instability is relevant for proteins in order for their molecular functions to be optimally rooted in their structures.

Animals↗

Lossy data compression with random gates.

We introduce a new protocol for a lossy data compression algorithm which is based on constraint satisfaction gates. We show that the theoretical capacity of algorithms built from standard parity-check gates converges exponentially fast to the Shannon's bound when the number of variables seen by each gate increases. We then generalize this approach by introducing random gates. They have theoretical performances nearly as good as parity checks, but they offer the great advantage that the encoding can be done in linear time using the survey inspired decimation algorithm, a powerful algorithm for constraint satisfaction problems derived from statistical physics.

Journal Article↗

Localization threshold of instantaneous normal modes from level-spacing statistics.

We study the statistics of the level spacing of instantaneous normal modes in a supercooled liquid. A detailed analysis allows us to determine the mobility edge separating extended and localized modes in the negative tail of the density of states. We find that at a temperature below the mode coupling temperature only a very small fraction of negative eigenmodes are localized.

Journal Article↗