From physics to biology by extending criticality and symmetry breakings

Description

Niveau: Supérieur, Doctorat, Bac+8
From physics to biology by extending criticality and symmetry breakings? Giuseppe Longo†, Maël Montévil‡ April 5, 2012 Contents 1 Introduction and summary 2 1.1 Hidden variables in biology? . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 Symmetry and objectivation in physics 4 3 Symmetry breakings and criticality in physics 7 4 Symmetry breaking and the biological object: extended criticality 9 5 Additional characteristics of extended criticality 12 6 Conclusion 14 References 14 Abstract Symmetries play a major role in physics, in particular since the work by E. Noether and H. Weyl in the first half of last century. Herein, we briefly review their role by recalling how symmetry changes allow to conceptually move from classical to relativistic and quantum physics. We then introduce our ongoing theoretical analysis in biology and show that symmetries play a radically different role in this discipline, when compared to those in current physics. By this comparison, we stress that symmetries must be understood in relation to conservation and stability properties, as represented in the theories. We posit that the dynamics of biological organisms, in their various levels of organization, are not “just” processes, but permanent (extended, in our terminology) critical transitions and, thus, symmetry changes. Within the limits of a relative structural stability (or interval of viability), variability is at the core of these transitions.

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Sujets

• Operation (mathematics)
• Entangled
• Changé

Informations

• Publié par: profil-zyak-2012
• Nombre de lectures: 20
• Langue: English

Extrait

Fromphysicstobiologybyextendingcriticalityand symmetrybreakings ∗ GiuseppeLongo † ,MaëlMontévil ‡ April5,2012 Contents 1Introductionandsummary2 1.1Hiddenvariablesinbiology?..........................3 2Symmetryandobjectivationinphysics4 3Symmetrybreakingsandcriticalityinphysics7 4Symmetrybreakingandthebiologicalobject:extendedcriticality9 5Additionalcharacteristicsofextendedcriticality12 6Conclusion14 References14 Abstract Symmetriesplayamajorroleinphysics,inparticularsincetheworkbyE.Noetherand H.Weylinthefirsthalfoflastcentury.Herein,webrieflyreviewtheirrolebyrecallinghow symmetrychangesallowtoconceptuallymovefromclassicaltorelativisticandquantum physics.Wethenintroduceourongoingtheoreticalanalysisinbiologyandshowthat symmetriesplayaradicallydifferentroleinthisdiscipline,whencomparedtothosein currentphysics.Bythiscomparison,westressthatsymmetriesmustbeunderstoodin relationtoconservationandstabilityproperties,asrepresentedinthetheories.Weposit thatthedynamicsofbiologicalorganisms,intheirvariouslevelsoforganization,arenot “just”processes,butpermanent(extended,inourterminology)criticaltransitionsand, thus,symmetrychanges.Withinthelimitsofarelativestructuralstability(orintervalof viability),variabilityisatthecoreofthesetransitions. Keywords:symmetries,systemsbiology,criticaltransitions,levelsoforganization, hiddenvariables,coherentstructures,downwardcausation. ∗ Publishedas:G.LongoandM.Montévil.2011a.Fromphysicstobiologybyextendingcriticalityand symmetrybreakings.SystemsBiologyandCancer,ProgressinBiophysicsandMolecularBiology106(2): 340–347. issn :0079-6107,doi: 10.1016/j.pbiomolbio.2011.03.005 † Informatique,CNRS–ENSandCREA,Paris,[e-mail], http://www.di.ens.fr/users/longo ‡ Informatique,ENSandEDFrontièresduvivant,ParisV,Paris 1