Złożoność, przypadek, samoorganizacja
Transkrypt
Złożoność, przypadek, samoorganizacja
ZŁOŻONOŚĆ, PRZYPADEK, SAMOORGANIZACJA: Plus ratio quam vis Paradygmaty ewolucji naukowo-kulturalnej w pracach Ilyi Prigogine’a Ewa Gudowska-Nowak Instytut Fizyki im. M. Smoluchowskiego i Centrum Badania Układów Złożonych im. M. Kaca, Uniwersytet Jagielloński w Krakowie Studium Generale Universitatis Wratislaviensis, 28.02.2012 1 wtorek, 13 marca 2012 „Nasza wizja przyrody ulega gruntownej zmianie ewoluując ku wielości, czasowości i złożoności... Zasada wzrostu entropii opisuje świat jako uklad przechodzący stopniowo do chaosu. Tymczasem ewolucja systemów biologicznych czy społecznych dowodzi, że to, co złożone wyłania się z tego, co proste... Brak równowagi , którego wyrazem jest przepływ materii i energii, może być źródłem porządku...” I.Prigogine, I. Stengers „Z chaosu ku porządkowi: Nowy dialog człowieka z przyrodą”, PIW, 1990 lIya Prigogine 1917-2003 Nagroda Nobla 1977 Tworzenie jest podstawową cechą Wszechświata, a kreatywność naukowa równoległa do kreatywności artystycznej ... (z wywiadu z E.Lévy, Le Point, 18.01,2002) 2 wtorek, 13 marca 2012 Samoorganizacja i uporządkowanie 3 wtorek, 13 marca 2012 • Samoorganizacja jest spontanicznym procesem tworzenia się uporządkowanych struktur przestrzennych i czasowych • Układy samoorganizujące się są emergentne (całość posiada własności odmienne od własności układów składowych) 4 wtorek, 13 marca 2012 Układy złożone: narzędzia opisu Ẋ = σ(Y − X) Ẏ = −XZ + rX − Y teoria układów dynamicznych, Ż = XY − bZ projekt Wolfram/Mathematica procesy stochastyczne, A. Bulsara, Physics Today, 1993 termodynamika nierównowagowa ui = kui − k � u3i + ε(ui+1 + ui−1 − 2ui ) + q sin ωt + K. Emanuel, Physics Today, 2006 5 wtorek, 13 marca 2012 tial evaporation rates, the air a short distance above the sea surface must be much drier than would be the case were it in equilibrium with the sea. √ Dξi (t) The hurricane as a Carnot heat engine. This two-dimensional plot of the thermodynamic cycle shows a vertical cross section of the hurricane, whose storm center lies along the left edge. Colors depict the entropy distribution; cooler colors indicate lower entropy. The process mainly responsible for driving the storm is the evaporation of seawater, which transfers energy from sea to air. As a result of that transfer, air spirals inward from A to B and acquires entropy at a constant temperature. It then undergoes an adiabatic expansion from B to C as it ascends within the storm’s eyewall. Far from the storm center, symbolically between C and D, it exports IR radiation to space and so loses the entropy it acquired from the sea. The depicted com- Układy złożone: narzędzia opisu teoria macierzy przypadkowych teoria grafów/sieci Table Examples of basic RNA structure motifs. Fromoftop to bottom: a single strand Bon,1: Vernizzi,Orland, Zee,secondary Topological classification RNA structures, Journal (PDB 283D [5]), a helical of duplex (PDB 405d [6]), a379 hairpin stem and loop (PDB 1e4p [7]), a bulge Molecular Biology (2008), p 900 (PDB 1r7w [8]), a multiloop (PDB 1kh6 [9]). From left to right: spacefill view, three-dimensional structure, secondary structure motif. The pictures are made with MolPov [10], Jmol [11] and PovRay [12]. 3 Hufnagel, Brockmann, Geisel, Rorcast and control of epidemics, PNAS, 101 (2004) p. 15 6 wtorek, 13 marca 2012 Fig. 1. Global aviation network. A geographical representation of the civil aviation traffic among the 500 largest international airports in #100 different Arises in statistical mechanical models e.g. BIFURKACJE w teorii układów dynamicznych of magnets or nieliniowych neural networks W układach zmiana parametru kontrolnego skutkuje pojawieniem się nowych rozwiązań stacjonarnych Plot y = x and y = β tanh x Example 3.4.1 ẋ = −x + β tanh x 3.4.1 ẋ = −x + β tanh x statistical mechanical models Fig. 3.4.3 ets or neural networks W pobliżu punktów bifurkacji istotną rolę zaczynają odgrywać fluktuacje: mogą one Arises in ostatistical mechanical models e.g. decydować wyborze gałęzi stabilnych stanów of magnetsdostępnych or neuralwnetworks stacjonarnych dynamicznej ewolucji układu... e.g. Plot y = x and y = β tanh x x and y = β tanh x Fig. 3.4.3 Poszukiwanie rozwiązań stacjonarnych: w prostych przypadkach wystarczą metody graficzne, współcześnie pełne rozwiązania problemów wielowymiarowych otrzymujemy numerycznie... 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B#1 " X#X Y #& X, E 64 05 n the Brusselator. We discuss and obtain a AND C. PÉREZ-GARCÍA PHYSICAL REVIEW B. PEÑA ed analytically with direct numerical simulations of the itude equation, including spatial modulasselator model. Sec. VI summarizes our conclusions. 2 2 thogonality are use nforms appearing in the model. This equa% t Yconditions "BX!X"Fredholm Y #D&alternative# Y, each order. In the neighborhood of the bifurcation point tained in many chemical models for stripe critical amplitudes A j follow the so-called normal fo II. THE REACTION-DIFFUSION MODEL the hexagonal case has not been discussed TheirYgeneral form canconcentrations be derived from standard techniq where X and denote the of activato of symmetry-breaking bifurcations %16'. A normal form #8–10$. From symmetry arguments, substrate, respectively. Here D is a parameter proportio The Brusselator is considered one some of the FIG. simplest 1. Turing patterns direct simulations of Brussin scribes perfect from extended patterns, but slight variations ed that it must include some nonpotential /D and, aswith us theinstadiffusion theincluded two Phys. species tion-diffusion models exhibiting Turing and Hopf B.ratio Pena,can C.ofPerez-Garcia, Rev. E. D 64of Y(2001) X 056213 pattern be byinitial means spatial terms , !0.04 hexagons, "b# , ! model (A!4.5,D!8): "a# besides the usual diffusive linear one ies. The spatiotemporal evolution of the main variables is keptisas the control parameter of theat problem. suitable symmetries, so one arrives the so-called ampli striped pattern, and "c# , !0.98 reentrant hexagons. FIG. 1. Turingtechnique patterns fromwe direct simulations of Brusselator s of multiple-scale compute equations. Westeady discuss state in the of following the form of is t en byathe following partial differential equations: The homogeneous these equations model (A!4.5,D!8): "a# , !0.04 initial hexagons, "b# , !0.30 equations for different planforms. f the amplitude equation for the Brusselator. "(X #9$. Let briefly recall he ply u striped pattern, and "c# , !0.98 reentrant hexagons. s s ,Y s )"(A,B/A) Stripes are characterized by us a single amplitude A 2 2 2 hexagons 2 ons of this% X"A! equation! B#1 are "stripes, B"1#! A around us . Consid X#X Y #& X, results of the linear stability evolves according to analysis t 2 2 L! t phases, mixed modes,B"1#! and distorted Ahexa2 2 . arrives at small perturbations u"(x,y) in Eqs. !1" one !1" 2 "B "A #D! 1 L!the stability of2 these "3# 2 . tability analysis sets 2 2 #D! "A ( 0 . t A! , A"g # A # 2 A# / 20 . x # . 2y A, % t Y "BX!X"B Y #D& Y, 2ik c ns in regard to amplitude disturbances. 1 mode B 2 Perturbations u are expanded in normal Perturbations u are expanded in normal modes u 2 ity limit is obtained from phase perturbawhich is the normal form for a supercritical bifurcation x % u"Lu# #2Axy#x y , t $ u exp & (k)t#ik•r leading to the eigenvalue equa! % ' re X and Y denote the concentrations of activator and Pierwowzór reakcji oscylacyjnej zaproponowany przez # k# !k 0 &(k)t#ik•r to variations, the eigenvalue A ' leading !1known ase cmuch # k# !k c u0 exp a %term that accounts for spatial mplitude varies more rapidly in time! $ 2 " (Here & (k)#)!0 in which ( and ) indicate the tion &i(k) strate, respectively. D is a parameter proportional to Prigogine’a Lefevera 2 Newell–Whitehead–Segel equation %17' in)convection and, therefore, it becomes enslaved by the & (k) " ( & (k)#)!0 in which ( and indicate tion trace and the determinant of the linear operator L, respecnomena. usual, BL is the linearized operator diffusion ratio of48 the(1968) two species D Y /D X and, as where J. Chem. Phys. 1695slight hases. The slow dynamics spatial tively. Depending on theofvalues of the parameters Aand and D trace the determinant of thebylinear operator sets L, ofres Squares are formed two perpendicular ept as thethecontrol parameter of the problem. system will undergo a Turing "stationary# bifurcation or a with equal wavevalues numbers,of i.e.,the "a# kparameters tively. Depending on the an 1!k2 and "b# # kA 1# ! The G. homogeneous steady state of these equations is simHopf instability. As a matter of fact, 2D reaction-diffusion Nicolis, I. Prigogine „Selforganization in Nonequilibrium symmetry inPhysical Fourier sp They display four ©2001 peaks with D4American 4!5"/056213!9"/$20.00 64 056213-1 The S the system will undergo a Turing "stationary# bifurcation systems that display Turing patterns also present a Hopf bi,Y )"(A,B/A) #9$. Let us briefly recall here the us "(X Systems” When condition "b# does not hold one obtains rectangula s s Wiley, New York, 1977 !1/D The latteranalysis gives risearound to oscillations if * + Hopf instability. As patterns; a matter of fact, bimodal instead, without2D the reaction-diffu condition "a# rho . Considering lts of thefurcation. linear stability u s 2 $( !1#A "1)/A %14'. Otherwise, a Turing instability takes "rhombicTuring cells# arise. Squares or present rhombs should o systems that display patterns also a Hop ll perturbations u"(x,y) in Eqs. !1" one arrives at place, the case we focus on hereafter. coupled equations of the kind: ( 0 . t A 1 ! , A 1 "g # A 1 # furcation. latter gives rise to oscillations if * + ! to a curve BThe"g Theukład marginal condition Nieliniowy reakcji i dyfuzji( & --!0) dla leads krytycznych wartości 0 # A 2 # A 1 , in which g 0 depends on k1 •k2 "valid for an 2 !B(k) kontrolnych the minimum of which yields the$( critical point /3). not around 1fluktuacje ! B 2 2 obserwowane 1#A "1)/A %14'.2 1Otherwise, a Turing instability parametrów są gęstości 2 *#2Axy#x ) , !A * ' . To describe naturally the sepa(B Hexagons are built up by three modes satisfying the r x % u"Lu# y , !2" c ,k c )! % (1#A t zmieniające się periodycznie w czasie i przestrzeni place, the case we focus on hereafter. A critical values the rescaled !1 parameter , nant condition ration from the k1 #k2 #k3 !0 "resonant triad#, with Brusselator ! ! " "! " ! ! ! " " "! " !0)break leads to a symm curv marginal ( &modes !(B"B c )/B c dubbed supercriticality, replaces BThe as the con! # k 2 #condition ! # k 3 # . When the the rotational 9 trol parameter. # ! # k 3 # ) squeezed hexagons but not reflexions ( # k 1 # 2 # k 2yields !B(k) the minimum of which the critical rewtorek, L 13ismarca theBefore linearized operator 2012 going to a perturbative analysis let us show exsult. Distortions breaking rotation and reflexion symmet Gdzie zawodzi tradycyjna termodynamika? •Aksjomatyczna, „tradycyjna” termodynamika jest [WHERE THERMODYNAMICS FAILS] CAUTION: BOTH HOT AND COLD elegancką, CONTENTS samozgodnąMAY teoriąBEmatematyczną. •Kluczowe pojęcia: stan, funkcja stanu, równanie stanu Temperature seems like such a simple, universal concept. Things may be hot or cold, but they always have a temperature, right? Not quite. It is possible to assign a temperature only to systems (such as the molecules in a glass of water) that are in, or almost in, a stable condition known as equilibrium. As systems deviate from equilibrium, the temperature becomes progressively more ambiguous. (wiąże ze sobą parametry stanu). SEVERE DISEQUILIBRIUM MODEST DISEQUILIBRIUM •Infnitezymalne, adiabatyczne zmiany stanu są odwracalne w czasie EQUILIBRIUM A glass of water, left undisturbed, comes to room temperature. The water molecules collide with one another and reapportion their energy so that their overall pattern of velocities stabilizes. Although the glass contains billions on billions of molecules, it takes only one number— the temperature — to describe this pattern. Classical thermodynamics applies. Heating the water from below disturbs the equilibrium. But if the heating is modest, individual layers of water remain approximately in equilibrium — socalled local equilibrium — and the water can be described by a temperature value that increases from top to bottom. The theory of nonequilibrium thermodynamics developed in the 20th century applies. If you crank up the heat, individual layers may no longer be even approximately in equilibrium. The molecules become a chaotic jumble in which the concept of temperature ceases to apply. To describe the system, you would have to introduce a raft of new variables and, in the most extreme case, specify the molecular velocities one by one. This situation demands a new theory. [WHY A NONEQUILIBRIUM THEORY IS NEEDED] ORDER FROM DISORDER Although the molecules in a system out of equilibrium may be hopelessly jumbled, the system can become ordered in other ways. MOLECULAR VELOCITIES Fraction of DYSSYPACJA NIE MUSI PROWADZIĆ DO CHAOSU! wtorek, 13 marca 2012 THE SECOND LAW A common example is when you put ice in a of the four laws of thermodynames, students apply thermodynamics to dynamic glass of water. The ice melts, and the water in the ics, the study of heat and energy. systems such as car engines to calculate quantiglass reaches a uniformly lower temperature. If Whereas the first law states that ties such as efficiency. But these applications you cannot get something for nothyou zoom in to the molecular level, you find an ing, the second law states that you make an implicit assumption: that we can apintense activity of molecules frantically moving cannot even get something for proximate a dynamic process as an idealized about and endlessly bumping into one another. something. Almost all processes succession of equilibrium states. That is, we In equilibrium, the molecular activity organizes lose some energy as heat, so to get imagine that the system is always in equilibrium, itself so that, statistically, the system is at rest; if something, you have to give someeven if the equilibrium shifts from moment to thing more. Such processes are some molecules speed up, others slow down, irreversible; to undo them exacts a moment. Consequently, the efficiency we calcumaintaining the overall distribution of veloci- toll in energy. Consequently: late is only an upper limit. The value that engines ties. Temperature describes this distribution; in reach in practice is somewhat lower because they fact, the very concept of temperature is meaningN Engines are inherently limited in under nonequilibrium conditions. particles is brought down to an average (if slight- chines is very deep. Fluctuationsoperate of the chemical their energy efficiency. fully only when the system is in equilibrium or sufThe second law describes how a succession fluctuating) value. Although a few isolated energy affect a molecular motor in the same ficiently near it. of equilibrium states can be irreversible, so that events may show completely unpredictable be- way that a random and variable amount of fuel N Heat pumps tend to be more Thermodynamics therefore deals only with the system cannot return to its original havior, a multitude of events shows a certain reg- efficient affectsthan thefurnaces, piston because of a carthey motor. Therefore, the MORE TO state situations of stillness. Time plays no role in it. In without exacting a price from its surroundings. ularity. Therefore, quantities such as density can move longrather tradition of applying than generate heat. thermodynamics to EXPLORE reality, of course, nature never stands still,For andthis large motors can be extended toAsmall melted ice Alcube does not spontaneously refluctuate but remain predictable overall. ones. Non-equilibrium Thermodynamtime does the matter. Everything is intoa rule constant form; you need it in the freezer, at a cost computer memory is an reason, second law continues over the N Erasing though physicists have other mathematical toolsto put ics. S. R. de Groot and P. Mazur. state of flux. The fact that classical thermodyirreversible act, so it produces heat. in energy. To quantify this irreversibility, the world of the small. for analyzing such systems, those tools can be J.M. Rubi, Scientific American, 2008 10 64From S C I E NSteam T I F I C A MEngines ERICAN to Molecular Motors tricky to apply. The equations of fluid flow, for example, require researchers specify the con© 2008 SCIENTIFIC AMERIC AN,toINC. ditions at the boundary of a system precisely— a ± Dover, 1984. Thermodynamics N o v e“beyond” mber 2008 Local Equilibrium. José M. G. Vilar DANIELA NAOMI MOLNAR W stanach odległych od równowagi, traci sens „zwykła” definicja/interpretacja temperatury Tradycyjna termodynamika nie opisuje przejść pomiędzy metastabilnymi stanami pośrednimi Teoria nie opisuje uporządkowania w stanach nierównowagowych Classical thermodynamics, cannot account for that, but the newly developed nonequilibrium theory can. Some textbooks define temperature based as it is on equilibrium, molecules as the average random velocity of molecules. In fact, temperature is the measure of an entire pattern of velocities. MODEST EQUILIBRIUM INCREASING SEVERE EXTREME In modest departures from equilibrium, An unheated glass of DEPARTURE DEPARTURE DEPARTURE DEPARTURE this pattern is merely shifted, but in water at room temperaA glass of water heated If the temperature gradiAs the heating increases, the As the heating increases severe departures, it is distorted, ture looks the same in Molecular velocity units) develops a (arbitraryent is larger, the water pattern of convection cells still further, the chaos berendering temperature meaningless. from below every direction, a symtemperature gradient. If begins to overturn, seteventually breaks down into comes equally distributed metry known as the gradient is too slight ting up an orderly pattern turbulent chaos. and the fluid recovers the isotropy. to overcome viscous resisof convection cells. lost isotropy. the two are in thermal equilibrium. that namics is limited to equilibrium situations may tance toFrom motion, the fluid remains static. point on, nothing changes. come as a surprise. In introductory physics classThe second law is the best known Warunki równowagi i teoria liniowej odpowiedzi układu Sν (Eν1 , Eν2 , ...) U1 U2 Stotal = � Sν (Eν1 , Eν2 ...) ν U1 ⊕ U2 izolowane Ej = E1j + E2j = const przy warunkach δS1 (E1j ) + δS2 (E2j ) = 0 ⇒ wtorek, 13 marca 2012 � ∂S1 ∂S2 − ∂E1j ∂E2j � δE1j = I1j − I2j ≡ 0 11 δE1j + δE2j = 0 ∀δE1j POZA STANEM RÓWNOWAGI „siły termodynamiczne” Xj ≡ � ∂S1 ∂S2 − ∂E1j ∂E2j � δE1j = I1j − I2j �= 0 siły termodynamiczne generują przepływy � ∂S dE1j dS = dt ∂A dt 1,j j W konsekwencji, produkcja entropii wyraża się prostym iloczynem sił i strumieni termodynamicznych Rozwinięta przez Onsagera (~1932) teoria liniowej odpowiedzi (słuszna dla słabych sił X) przewidywała Φj = � k IIga zasada narzuca warunek j � dS Lkj Xk ⇒ ≈ Lkj Xk Xj dt k dS ≥0 dt 12 wtorek, 13 marca 2012 dE1,j = Φj dt � = X j Φj Termodynamiczna analiza stabilności: Kryterium stabilności Glansdorffa - Prigogine’a nierównowagowych stanów stacjonarnych w oparciu o „nadmiarową produkcję entropii” 2 ∂ 2 (δ S)N SS ∂t (δ S)N SS < 0 � = δJk δXk > 0 k I. Prigogine, Science 201, 777 (1978) Nobel Lecture kryterium lokalne, wystarczający (ale nie konieczny) warunek lokalnej stabilności stanu stacjonarnego 13 wtorek, 13 marca 2012 To illustrate we use a characterization of the Ising model [77]. Imagine a 2D grid of lights of varying brightness (from off to maximum), where brightness is a function of two variables. One is a random noise factor (individual to each light) and the other is a neighbor conformity factor whereby each light tends towards the brightness of its four nearest neighbors on the grid. These two variables are weighted together to determine the brightness of each light. In this illustration, the correlation function measures the degree to which lights have equal brightness levels as a function of their distance apart on the grid. If noise is heavily weighted, then interactions are somewhere between independent and interdependent. Weak interactions can result in short-range correlations (Figure I green) that decay exponentially with distance. Stronger interactions can result in long-range correlations that decay more slowly (Figure I pink) (i.e. as an inverse power of distance). The correlation function can also be defined for distances in time, with an analogous comparison between weak (short-range) versus strong (long-range) interactions. No interactions can result in uncorrelated noise (Figure I grey), and integrating over uncorrelated noise results in a random walk (Figure I brown). Prawa skalowania: układy złożone - przebieg zjawisk obserwowany jako szereg czasowy szereg czasowy funkcja korelacji widmo mocy Figure I. Four example time series are plotted in the left-hand panel: random samples from a normal distribution with zero mean and unit variance (i.e. white noise, in grey), a running sum of white noise (i.e. brown noise, also known as a random walk, in brown), 1/f noise (i.e. pink noise, in pink) and an autoregressive Kello average et al,Trends in Cognitive moving (ARMA, in green), where each sampled value is a weighted sum of a noise sample, plus the previous noise value, plus the previous sampled Sciences, 14, p.223-232 (2010) value. Idealized autocorrelation functions are shown in the middle panel for each of the time series, where k is distance in time. Note that white noise (i.e. pure independence) has no correlations, ARMA has short-range correlations that decay exponentially with k, 1/f noise has long-range correlations that decay as an Rozkłady potęgowe inverse power of k and brown noise has correlations that decrease linearly with k. Idealized spectral density functions (where f is frequency and S( f) is spectral obserwowane dla!1wielu power) are shown in the right-hand panel in log–log coordinates. White, pink and brown noises correspond to straight lines with slopes są of 0, and !2, whereas różnych zjawisk (rozkład ARMA plateaus in the lower frequencies. długości czasów trwania trzęsień −α ziemi, energii wybuchu, masy lawin, etc...) range correlations in collective measures of component activities. These predictions are supported by the evidence reviewed here for neural avalanches [62], power-law distri- S(f ) = const × f Szum różowy: envelope can be illustrated by tracing a line from peak to 14 peak along a given waveform (i.e. the convex hull). Interwtorek, 13 marca 2012 estingly, the temporal scaling of amplitude fluctuations in Układy samoorganizujące się są dyssypatywne - charakteryzuje je pobór i straty energii Uporządkowanie obejmuje całość układu, a dynamiczna zmienność jest zdeterminowana fluktuacjami parametrów kontrolnych Układy samoorganizujące się cechuje wysoki stopień adaptacji do warunków zewnętrznych i wysoka odporność na zniszczenia 15 wtorek, 13 marca 2012 Niespójność? Determinizm mikroskopowych praw natury i kierunkowość zjawisk ewolucyjnych w przyrodzie Czas jest iluzją... A. Einstein [...]Im głębiej analizujemy naturę czasu, tym lepiej rozumiemy, że trwanie oznacza inwencję, tworzenie form, stałe doskonalenie absolutnie „nowego”... Czas rzeczywisty (fizyczny) i czas subiektywny (durée) Henri Bergson 1859-1941 Nagroda Nobla 1927 [...]W naturze istnieje wielkość, która zmienia się w tym samym sensie we wszystkich procesach naturalnych... Byłoby absurdem twierdzić, że zasada wzrostu entropii jest wynikiem naukowej obserwacji, niedoskonałości eksperymentalnego pomiaru... Max Planck 1858-1947 Nagroda Nobla 1918 wtorek, 13 marca 2012 16 using solely the microscopic dynamical laws: the above time symmetry implies that if (a, b, c, d) is a possible ordering so is (d, c, b, a). The explanation of this apparent paradox, due to Thomson, Maxwell and Boltzmann, as described in references [1−13], shows that not only is there no conflict between reversible microscopic laws and irreversible macroscopic behavior, but, as clearly pointed out by Boltzmann in his later writings1), there are extremely strong reasons to expect the latter from the former. These reasons involve several interrelated ingredients which together provide the required distinction between microscopic and macroscopic variables and explain the emergence of definite time asymmetric behavior in the evolution of the latter despite the total absence of such asymmetry in the dynamics of the former. They are: ■ the great disparity between microscopic and macroscopic scales, ■ the fact that the events we observe in our world are determined not only by the microscopic dynamics, but also by the initial conditions of our system, which, if taken back far enough, inevitably lead to the initial conditions of our universe, and ■ the fact that it is not every microscopic state of a macroscopic system that will evolve in accordance with the entropy increase predicted by the second law, but only the „majority“ of such states − a majority which however becomes so overwhelming when the number Dlaczego nie obserwujemy ewolucji verned by Hamiltonian dynamics with some specified blem and w czasie? Hamiltonian H(X) whichodwróconej we will assume for simplicity Jakie są przyczyny symetrii to be an even function of the momenta:łamania no magnetic stinctly different time t , fields. Given H(X), the microstate X(t), odwrócenia watczasie? sn’t unspill, eggs determines the microstate X(t) at all future and past s break but do not times t during which the system be or was isolated: różnice skal mikrowill i makro •istotne układów dynamicznych determinowana ver younger. These X(t) = Tt–t X(t•ewolucja ). Let X(t ) and X(t + τ), with τ posi- jest nie tylko przez prawa mikroskopowe, ale także przez warunki in time − they tive, be two such microstates. Reversing (physically or początkowe efine the arrow of we obtain mathematically) all velocities at time t + τ,będzie mikroskopowy stan układu ewoluował •nie każdy zgodnieIfz we zasadą entropii, a jedynie większość that the relevant a new microstate. nowwzrostu follow the evolution for spośród takichτstanów no such distinction another interval we find that the new microstate at laws permit all pro- time t + 2τ is just RX(t), the microstate X(t) with all 42 Journal 6, (2007) J. Lebowitz, Physik . This leads to a great velocities reversed: 41-46 (M.Planck Medaille) it it why don‘t we RX = (r,–p, r, – p, ..., rN, – pN). esses run backwards? ring run backwards Hence if there is an evolution, i. e. a trajectory X(t), how can time-rever- in which some property of the system, specified by a les, the microscopic function in a certain f(X(t)), behaves N Nway as t increaive rise to observed ses, then if f (X) = f (RX) there is also a trajectory in veryday world? which the property evolves in the time reversed direc17 ory, the „theoryi tion. i wtorek, 13 marca 2012 a sible motions of atoms and molecules, the m components of material systems, give rise t time-irreversible behavior of our everyday In the context of Newtonian theory, the „ of everything“ at the time of Thomson, Max Boltzmann, the problem can be formally pr follows: the complete microscopic (or micro classical system of N particles is represented X in its phase space Γ, b c d Fig. 1 How would you order this sequence of „snapshots“ in time? Each represents a macroscopic state of a system containing, for example a fluid with two „differently colored“ atoms or a solid in which the shading indicates the local temperature. Physik Journal 6 (2007) Nr. 8/9 © 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim X = (r , p , r , p , ..., r , p ), r and p being the position and momentum Termodynamiczna strzałka czasu wyznaczana procesami dyfuzji, wzrastającymi korelacjami i pojawieniem się zachowań kolektywnych w układach wielociałowych The persistence of memory, S. Dali (1931) W podejściu (filozofii) Szkoły Brukselskiej, kierunkowość czasu jest podstawowym zjawiskiem wynikającym z dynamiki złożonych układów fizycznych Rozszerzenie teorii Poincaré: układy równań dynamicznych są niecałkowalne jeśli zawierają rezonanse pomiędzy rozmaitymi stopniami swobody Rezonans: przejściowy stan metastabilny układu stwarzający możliwość efektywnego przekazu energii 18 wtorek, 13 marca 2012 "2:19-)(2&$,*;"(9(="*>?@*"*>?AB*)".1'(*7+8C*(*%)"j%(2&$,*6-3#2$D(<2"#*%*"2:19$Dj .(9(*)j3.-;&E*F;(*3#*;"(9(*)&9(%1Dj*"23#.(9$D*%*9-=6<#9'#=*;"(#9*;"-.j$&$,*1:%"( )*(:,#%D"*9-=4.#9*:-*=($"#.%&*6-%(9-=4.9-)#DC*(*%*9-<#"*3#*%)"j%(2#*%*(93&2(="*"*$&G NEWS & VIEWS Q&A 3-'%9"#<#3#=*6#2"j*H129$D*)*=-;"<2-È$"*"*="5.($D"*9-=4.#9E*I-%.#51<-)(2"#*3&$, H129$D"*6.%#%*;"(9(*>?@*"*>?AB*=-ß#*6.-)(:%"o*:-*%(;1.%#¦*=-;"<2-È$"*9-=4.#9 -:$%#6"#2"(*'"*"$,*-:*6-%(9-=4.9-)#D*=($"#.%&C*(*2('362"#*:-*%(6-$%j39-)(2"(*9(2G Box 1 | The discovery of chromosome territories $#.-5#2#%&*"*6.-5.#'D"*2-)-3)-.1E Nurty współczesnej teorii układów złożonych (podejście synergetyczne) w naukach biologicznych (biologia systemów) a Random organization model Chromosome territory model Laser damage Laser damage Prediction Prediction b I I&$E*JE*K.(H"$%2(*"<1'3.($D(*"23#.(9$D"*=":%&*;"(9(="*7+8*"*;"(9(="*$%-)"#9(E*(L*?"#o*"23#.G (9$D"*;"(#9*$%-)"#9(*M7G7N*9-<-.*2"#;"#'9"LC*61293&*)*9-<-.%#*$%#.)-2&=*-%2($%(Dj*$%j'3#$%9" ;"(9(*6-*%(9(ß#2"1*7+8E*;L*?"#o*"23#.(9$D"*8G7E*O%&*)*9-<-.%#*$%(.2&=*P*;"(9(*)".1'-)#N )*9-<-.%#*$%#.)-2&=*P*;"(9(*<1:%9"#N*j$%2"9"*$%#.)-2#*P*"23#.(9$D(*=":%&*;"(9(="*<1:%9"=" "*)".1'-)&="N*)%&*2"#;"#'9"#*P*"23#.(9$D#*=":%&*;"(9(="*<1:%9"="E*>(D)"9'%&*9-=6-2#23 '"#$"*MÈ.-:#9*.&$"2&L*-;#D=1D#*QJR*$%j'3#$%#9*;"(9-)&$,E*O5*:#*+,(''#&*SEC*>(T.(3"<*8EC*U(HH-G .#(1*VE*MW00/LX*7#6(3"3"'*+*T".1'*"2H#$3"-2*6.-3#"2*2#3)-.9E*Y!-<#$1<(.*?&'3#='*S"-<-5&ZC*[X*W@0 II 0 III 1 2 3(=X)–5 6–8 9–11 F$%#91D#*'"C*ß#*6-%2(2"#*(.$,"3#931.&*"*-54<2&$,*)(È$")-È$"*'"#$"*9-=4.9-)&$, M. Chorąży, Nauka 1/2011 At the turn of the twentieth century, occupied distinct territories (a, left panel), T. Misteli, Nature, 445 379-381 (2007) "*"23#.(9$D"*;"(9-G;"(9-*6-%)-<"*2(*;1:-)(2"#*1-54<2"-2&$,*,"6-3#%*-*=-<#91<(.2&$, Carl Rabl and Theodor Boveri proposed localized damage would affect only a that each chromosome maintains its small subset of chromosomes, whereas if 6-:'3()($,*ß&$"(C*.-:%(D($,*.#51<($D"*#9'6.#'D"*5#24)C*"23#.(9$D"*=":%&*6-:'"#$"(="C individuality during the cell cycle, and the chromatin fibres of each chromosome '3(;"<2-È$"*"*#<('3&$%2-È$"*'"#$"E*+#<#=*;"-<-5""*'&'3#=4)*D#'3*3(9ß#*2-)(*9<('&H"9($D( Boveri explained this behaviour in terms were randomly distributed throughout the 19of ‘chromosome territories’. $,-.4;C*:"(52-'3&9(*"*3#.(6"(E*!-ß<")#C*ß#*1:(*'"*)'9(%(o*3(9"#*)%&*"*6-j$%#2"(*)*'"#G nucleus (a, right panel), many chromosomes wtorek, 13 marca 2012 The existence of chromosome territories was demonstrated experimentally during would be damaged. b, Three sets (I–III) of hamster chromosomes after laser Podsumowanie i „luźne” wątki... Powszechność układów złożonych i zjawisk samoorganizacji czasowoprzestrzennej w różnych skalach obserwacji przyrody (od biologii po kosmologię..) sugeruje, że zrozumienie charakteru „praw” , mechanizmów odpowiedzialnych za „samoporządkowanie” i spontaniczne powstawanie struktur może być kluczem do spójnego opisu materii. Czy (nieliniowa) dynamika, przyczynowość i przypadek (fluktuacje) są wystarczającymi elementami tego opisu? 20 wtorek, 13 marca 2012 [...] Przesłanie Jacquesa Monoda mówi: życie, a w szczególności człowiek jest niereligijnym cudem. Wedlug mnie jest inaczej . Materia posiada potencjał związany z samoorganizacją, z którego właściwie nie zdawano sobie sprawy w czasach Monoda. Z drugiej strony, przesłanie Sartre’a i Camusa mówi, że wszechświat jest absurdalny.To poczucie absurdu jest naturalne we wszechświecie, w którym człowiek jest oderwany od otaczającej go przyrody.Walczyłem z tymi poglądami wykazując, że istnieje pewna racjonalność, ale że zawiera ona niepewność i strzałkę czasu... I. Prigogine (wywiad z E.Lévy, Le Point, 18.01,2002) 21 wtorek, 13 marca 2012 Dziękuję za uwagę Plus ratio quam vis 22 wtorek, 13 marca 2012