Understanding the hierarchical URLanization of living systems is a challenge that requires the development of a multiscale description of their constituents. A generically observed mechanism that drives URLanization is interaction among the individual elements---which may represent cells, bacteria, or even enzymes---via chemical signals. We develop a systematic coarse-graining scheme using which we can construct a general theoretical framework to study many-body effects in chemotactic populations. The framework unveils a polarization-induced coupling term , which originates from quorum effects and can compete with the chemotactic drift term. We use the dynamical renormalization group approach to study a stochastic model for chemotactic particles in which we introduce polarization effects in chemotaxis. We find exact dynamic scaling exponents that represent superdiffusive behavior of the particles. The number fluctuations within subregions of the system show a hyperuniform structure or exhibit giant number fluctuations, depending on whether or not the noise is conserved . We expect our results to shed light on how molecular regulation of chemotactic circuits can determine large-scale behavior of cell colonies and tissues through emergent properties that result from a subtle interplay between nonequilibrium fluctuations and long-range interactions that are constrained by exact symmetries .
 A generically observed mechanism that drives the URLanization of living systems is interaction via chemical signals among the individual elements -- which may represent cells, bacteria, or even enzymes. Here we propose a novel mechanism for such interactions, in the context of chemotaxis , which originates from the polarity of the particles and which generalizes the well-known Keller--Segel interaction term. We study the resulting large-scale dynamical properties of a system of such chemotactic particles using the exact stochastic formulation of Dean and Kawasaki along with dynamical renormalization group analysis of the critical state of the system . At this critical point, an emergent "Galilean" symmetry is identified, which allows us to obtain the dynamical scaling exponents exactly; these exponents reveal superdiffusive density fluctuations and non-Poissonian number fluctuations . We expect our results to shed light on how molecular regulation of chemotactic circuits can determine large-scale behavior of cell colonies and tissues .
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Understanding the hierarchical URLanization of living systems is a challenge that requires the development of a multiscale description of their constituents.
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URLanization is interaction
the URLanization of living systems is interaction via chemical signals
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elements---which
elements -- which
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enzymes---via chemical signals. We develop a systematic coarse-graining scheme using which we can construct a general theoretical framework to study many-body effects in chemotactic populations. The framework unveils a polarization-induced coupling term
enzymes. Here we propose a novel mechanism for such interactions, in the context of chemotaxis
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quorum effects and can compete with the chemotactic drift
the polarity of the particles and which generalizes the well-known Keller--Segel interaction
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use the dynamical renormalization group approach to study a stochastic model for chemotactic particles in which we introduce polarization effects in chemotaxis. We find exact dynamic scaling exponents that represent superdiffusive behavior of the particles. The number fluctuations within subregions
study the resulting large-scale dynamical properties of a system of such chemotactic particles using the exact stochastic formulation of Dean and Kawasaki along with dynamical renormalization group analysis of the critical state
R
show a hyperuniform structure or exhibit giant number fluctuations, depending on whether or not the noise is conserved
. At this critical point, an emergent "Galilean" symmetry is identified, which allows us to obtain the dynamical scaling exponents exactly; these exponents reveal superdiffusive density fluctuations and non-Poissonian number fluctuations
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through emergent properties that result from a subtle interplay between nonequilibrium fluctuations and long-range interactions that are constrained by exact symmetries