1 Introduction

Describing emergent phenomena as facing biological organizations succumbs inescapably to internal confrontation between two different types of agent. One is the author of description, and the other is an agent experiencing emergent novelty. Any objective description requires the author to remain external to the description itself, while emergent phenomena in biology internalize those agents experiencing novelties. A serious question that may come up at this point is whether or not the author of description and the agent experiencing emergent novelty could be identical.

If the author and the experiencing agent are one and the same as facing emergent phenomena, both the description and the descriptive object to be experienced will remain external to the act of describing and experiencing. External description prohibiting itself from referring to its author certainly satisfies the condition necessary for being objective and perspicuous in its own right.¹ Likewise, the presence of the object to be experienced externally assumes that the experiencing agent performs measurement externally and that perspicuous objectivity of the outcome is its natural consequence.

External description of external measurement, however, suffers from its methodological peculiarity of seeking the origin of emergent novelty solely outside what has been experienced and described. Measurement external to an object exhibiting an emergent novelty has nothing to do with the process of giving rise to the very emergent phenomenon. The present externality of emergent novelty is totally vulnerable to what cannot be described and experienced externally. Only the consequence of emergent phenomena is visible to external description of external measurement. If it is intended to decipher how emergent phenomena could come into being, one would have to go beyond external description of external measurement.

We shall in the present article try to establish a descriptive scheme that can cope with emergent novelty occurring in biological organizations and the underlying cohesiveness being responsible for their coming into being. In order to accomplish the present objective, let us first examine how external description of external measurement would proceed in its more details.

2 External Description of External Measurement

Emergent phenomena require both duration in time and variations acting upon it. If measurement is external in the sense that an object out there exists exactly as it is as measured externally and if the consequence of the measurement is describable without any reference to the author, the notion of duration in time can be sanctioned without any recourse to variations to be imposed. Galilean inertia just happens to be the case. However, the notion of duration met in evolutionary processes at least during the last 3.8 billion years on the earth is quite different from that of Galilean inertia. Molecular replication as a common denominator of the emergent phenomena called life on the earth makes it inevitable to be accompanied by the process of generating variations or making products successively without any interruptions.²

Variable duration is inherent to molecular replication, and is totally foreign to invariant duration unique to Galilean inertia.³ External description of external measurement would make the occurrence of molecular replication no more than an extremely unlikely event paraphrased as a frozen accident. In fact, quantum mechanics understood as external description of external measurement cannot raise such a replicating molecule by itself.⁴ Evolutionary emergence of replicating molecules presumes a unilateral sequence of synthetic molecular reactions in which some of the products re-enter into an arbitrary stage in the whole reactions as further reactants, while every reaction or interaction conceivable within external measurement of quantum mechanics is bilateral as admitting both associative and dissociative reactions everywhere at the same time.

Invariant duration cannot serve as an evolutionary precursor of variable duration because of their intrinsic incommensurability. The same difficulty also applies to the notion of natural selection understood as differential retention of slightly modified heritable traits.⁵ Underlying natural selection is also variable duration. In particular, if one raises a question of how natural selection could come into being, it would not be feasible any more to have recourse to an onset of molecular replication because both are grounded upon the same notion of variable duration. The present impasse may suggest to us either that the question asking the evolutionary onset of variable duration would be in itself wrongly formulated or that external description of external measurement by itself be methodologically incompetent in coping with such question.

At this point, it is worth pointing out that the relationship between description and measurement is not restricted to the case that both are external. One cannot deny the historical fact such that external description of external measurement has greatly contributed to the promulgation of objective and rigorous sciences over the last few hundred years. Nevertheless, the externality of both description and measurement is no more than merely one frame of reference conceived from and applied to the pair. Measurement in its rudimentary form presumes our sense perception, and description is framed upon our natural languages serving as the infra-structure.

Externalization of both description and measurement is simply a consequence of applying a form of abstraction to both of them by eliminating any agential capacity from the object of description and experience. Otherwise, describing experiences remains internal in the sense that the one who measures and describes the experience of its own is constantly measured and described by others internally as in ordinary conversations in everyday life. The present internal chain of description and measurement has neither its beginning nor end. The agents of both description and measurement are internalized in their mutual acts. This way of looking into the interplay between the two suggests an occurrence of internal description of internal measurement as an opposite extreme case.

3 Internal Description of Internal Measurement

In ordinary conversations in everyday life, everybody as an agent of measuring and describing is constantly measured and described by others. This is exactly the problem area which traditional rigorous sciences have shrewdly avoided up until now. It is of course legitimate to observe that rigorous sciences cannot derive from ordinary conversations that constantly have recourse to the speakers. That rigorous sciences cannot be brought about from mere ordinary conversations rests upon the indefiniteness of the viewpoint of each internal description attempted there. What is unique to internal description is the recursiveness of letting itself be an object to further be measured by others internally within the framework of on-going ordinary conversations. Henceforth, indefinite continuation of ordinary conversations is found to be within indefinite succession of internal description of internal measurement.

The context of ordinary conversations, however, constantly varies with their progression. There is no universality nor a priori invariance in the context in the making. The variability of the context in an unprecedented manner is an undeniable empirical fact in ordinary conversations. Curiously enough, however, ordinary conversations, if properly abstracted, can happen to give birth to objective description and rigorous sciences. In order to objectify ordinary conversations in everyday life, it would again be required to externalize either description or measurement. If both description and measurement are externalized as in traditional rigorous sciences, a cost would inevitably be incurred. No descriptive enterprise coping with historicity and evolutionary processes could be expected therefrom. If experiencing and describing emergent phenomena are intended beyond those intended by internal description of internal measurement, either description or measurement would again have to be externalized.

4 Internal Description of External Measurement

If the external object exists as perceived by our sense organs, this would guarantee the occurrence of experiences upon which rigorous empirical sciences could stand. However, experiences by themselves cannot result in objective and rigorous sciences, the latter of which depend entirely upon how these experiences could be described. Internal description of internal measurement as practiced in ordinary conversations in everyday life certainly provides an infra-structure upon which rigorous sciences could be constructed. What is required for this construction is an abstraction. The present application of an abstraction, though a necessary condition for deriving objectivity therefrom, may induce further reverberations. In fact, if an abstraction of eliminating any agential capacity of measurement from an object to be measured is taken in the form of external measurement, the measured object will turn out also to be an object to be described externally. External measurement now necessitates external description in order to put its intended objectivity into a definite descriptive form.

Nevertheless, if internal description of external measurement is attempted as in the case that there may be allowed many descriptive perspectives internally while maintaining a unique external measurement of the whole, a certain pathological situation would come up. A schizoid separation of the authorship would inevitably follow between the externalist and the internalist stance. The internalist authorship cannot set its descriptive perspective without recourse to the arbitrary internalist stance it assumes, while the externalist counterpart grounds itself upon the invariant stance that guarantees the object to be externalized. Internal description of external measurement would simply be a misnomer at best or a methodology to be avoided earnestly. These considerations come to leave external description of internal measurement as an only likely choice for coping with emergent phenomena to be experienced and to be described.

5 External Description of Internal Measurement

Objective description that has to be observed in any case is external in keeping itself from referring to its author. In spite of the present externality of description, measurement remains internal as our sense perception is. Of course, rigorous sciences based upon the stipulation asking the object of sense perception to stand alone externally as perceived necessitate external description, but the latter does not necessitate external measurement. External description is simply a linguistic pre-condition for aiming at objectivity of intended description.

In fact, the agency of measurement is not monopolized by our sense organs. Any material bodies interacting among themselves can serve as the agents performing measurement.^3,6 In view of the fact that measurement is a most prevailing form of interaction distinguishing between before and after the events and that nothing propagates faster than light, measurement is synonymous with the presence of matter. Measurement is thus internalized within interacting material bodies of any kind endophysically.⁷ The problem that now comes up is how to externally describe the contribution of internal measurement.

One of the necessary conditions for external description is the observation of the principle of the excluded middle. Since external description is synonymous with the consequence of description attempted externally, the principle of the excluded middle guarantees the global consistency of description in the product. On the other hand, internal measurement in the making is local both in space and in time. In order to approach the global consistency of external description from internal measurement, a certain condition has to be imposed internally upon the progression of internal measurement. That is that internal measurement proceeds so as to fulfill the principle of the excluded middle in the effect. Internal measurement for the sake of the principle of the excluded middle is a consequence of the global consistency of external description. Put differently, if the global consistency of description in the product fails, internal measurement for the sake of the principle would also fail. The present reflection now raises a serious question on the likelihood of objective description to be externalized. The principle of the excluded middle is a consequence of descriptive objectivity, and not vice versa.

In order to justify the occurrence of external description, something that could remain invariant and objective globally has to be sought in the product of internal measurement. Although each internal measurement is local, the globality of the product makes itself be an object to be measured externally.⁸ As far as the consequence of internal measurement is concerned, external measurement can safely intervene there without causing any conflicts with the former. If there is found an invariant quantity within the consequence of internal measurement, that quantity can also be identified by external measurement. Energy to be conserved just happens to be such a quantity, thanks to Robert Mayer. Observation of the conservation of energy by external measurement also confirms the progression of internal measurement for the sake of the conservation in the effect. The present interplay between external and internal measurement as facing the conservation of energy is to provide a means for legitimizing the objectivity of external description of internal measurement. This is owing to the presence of an invariant quantity being independent of descriptive artifacts. What makes external description of internal measurement meet the principle of the excluded middle happens to be the conservation of energy.

Fulfilling the conservation of energy through internal measurement is a local process. The local activity for the sake of the conservation of energy on a global scale lets each interacting material body be an energy consumer acting toward its outside from the inside as wanting or yawning for energy resources in order to compensate the preceding energy consumption in whatever way.⁹ The occurrence of energy consumers is thus unique exclusively to external description of internal measurement,¹⁰ and can be totally dismissed in the framework of external description of external measurement. There is no room of agential capacity in the object that is supposedly measured externally.

The significance of energy consumer for emergent phenomena is multifarious. Evolutionary emergence of the phenomenon called life at about 3.8 billion years ago on the earth happened to be an instance of raising a very primitive form of energy consumers. In addition, energy consumers exert a specific form of cohesive force toward their energy resources.^9,11 Compared to various mechanical forces imposed externally in the form of fixed boundary conditions, cohesive forces unique to energy consumers act from its inside toward the outside. Above all, energy consumers carry with themselves the capacity of variable duration as constantly wanting energy resources while being exploited by others at the same time.¹² External description of internal measurement that can come up with energy consumers installs in itself the capacity of variable duration as a necessary condition for emergent phenomena.

Energy consumers are accompanied by energy dissipation whenever and wherever. Energy dissipation is just one instance of describing externally what is being measured internally. What has been measured internally can in turn be measured externally in the completed record at the global scale, for instance, in mechanistic terms of generalized fluxes and their conjugate generalized forces.¹³ Nonetheless, cohesive forces yielding energy dissipation are more than what mechanistic forces would literally imply. It is the operation of measurement proceeding internally which signifies the genuine implication of cohesive forces underlying the emergence of energy dissipation in general and energy consumers in particular.

6 Cell Motility: An Example

6.1 Perpetual Disequilibrium between Energy and Momentum Conservation

Recently, a considerable amount of experimental efforts for identifying the physical nature of

molecular motors involved in muscle contraction has been accumulated.^14-19 What we may require at this point might be to identify each physical process constituting the operation of molecular motors in their motile organization from the perspective of internal measurement and cohesive interaction.

When it hydrolyzes an ATP molecule, a myosin molecule contacting an actin filament can release the energy stored in the ATP and transform it into the energy of excitations activated along the actin filament. The resultant momentum of the generated excitations measured in the coordinate system resting on the myosin molecule should vanish because the ATP molecule as an energy source remains stationary with respect to the coordinate. A most simple form of excitations is a pair of excitations whose energies are e(k) and e(-k), in which e(k) is the energy of an excitation carrying momentum k with e(k)=e(-k). An example of a likely pair of excitations is an exciton as a bounded particle-hole pair excitation activated along the actin filament.20

On the other hand, quantum mechanics of such a pair-excitation tells us that the uncertainty principle still imparts an uncertainty in the momentum by the amount of Dp_x to the excitation spread spatially over the linear extent of Dx along the x-direction in parallel to the filamental longitudinal axis, with the constraint

in which h is Planck's constant divided by 2p. The uncertainty Dp_x in momentum cannot however survive indefinitely, otherwise momentum conservation would be violated.²¹ In order to restore momentum conservation, another excitation carrying momentum -Dp_x with its energy de has to be generated spontaneously. The source of such spontaneous excitation again should be due to the uncertainty principle in the form of

The uncertainty de in energy, however, has to be compensated similarly, otherwise energy conservation would be violated.^3,6 If the source of energy compensation is supplied externally as in the form of ATP molecules to be hydrolyzed, the restoration of energy conservation could certainly be accomplished by annihilating the excitation carrying energy de while filling the energy deficiency caused by the operation of the energy-time uncertainty principle. Unless the energy source supplied externally is available, there would be no such compensation. Nonetheless, the restoration due to annihilating the excitation carrying the momentum -Dp_x would again come to violate momentum conservation by the amount of Dp_x if noting is accompanied. Fulfilling momentum conservation would lead to violating energy conservation if nothing is accompanied and vise versa.

Disequilibrium between energy and momentum conservation thus perpetuates.³ Equilibration for the sake of eliminating disequilibrium causing violation of conservation laws constantly yields further disequilibration.⁸ What is constantly occurring is indefinite sequential alternation between otherwise violating energy conservation for the sake of fulfilling momentum conservation and violating momentum conservation for the sake of energy conservation. Of course, the net result to be observed in the record is both energy and momentum conservation.

The present perpetual disequilibrium between energy and momentum conservation can be facilitated so long as the energy compensation from ATP molecules is available. When the energy e_ATP is released from a single ATP molecule uniformly over the time interval t_ATP, the compensation for energy conservation requires

In addition, the fluctuation Dp_x in momentum is related to the force f acting there through the relationship of the impulse

and the displacement Dx is related to the sliding velocity v of the actin filament against the fixed myosin molecule as

The relationship connecting the force f to the sliding velocity v now reduces to

An experimental confirmation of the generation of motile force due to perpetual disequilibrium between energy and momentum conservation can be obtained by examining each measured value of the force f~2x10^-7dyne,^22,23 the sliding velocity v~4x10-4cm/s,16 the energy released from an ATP molecule e_ATP~10^-12erg,¹⁴ and the turn-on time of ATP to be hydrolyzed in an actomyosin complex t_ATP~10^-2s.^16,23 These measured values certainly satisfy an approximate equality fv~e_ATP/t_ATP~10^-10erg/s at room temperature.

Motile force due to perpetual disequilibrium between energy and momentum conservation in the actomyosin complex is cohesive in that both an actin filament and a myosin molecule are attracting each other. The physical origin of the attractiveness is within fulfilling conservation laws altogether from the inside,¹⁰ while the attractive activity does not fail in constantly leaving further causes for the similar activity in the subsequent stage. Sliding movement of the actin filament, whether or not accompanied by power stroke of a swinging movement of the head of a myosin molecule,^16,24 is simply a derivative of the underlying attractive interaction between those components comprising the motile organization. The attractive interaction is sufficiently long-ranged both in space and in time because conservation laws are not localized in their extent.

In particular, cohesive forces acting in the actomyosin system are direct manifestation of a most fundamental attribute of quantum mechanics, namely, an interplay between the uncertainty principles on energy and on momentum. Measurement of energy (or momentum) subject to its conservation would necessarily come to yield the uncertainty principle on momentum (or energy) violating its conservation if left alone. Since both energy and momentum have to be conserved in the long run, measurement has to be internalized in the sense that any measurement having come to terms with conservation of energy internally induces another measurement going to observe conservation of momentum also internally and vice versa, interchangeably in sequence indefinitely. Internal measurement observing conservation laws in the record constantly passes the operation of the uncertainty principle onto the subsequent stage, while inducing further internal measurement.²⁵

The quantum coherence underlying the generation of motile force in the actomyosin system is thus seen due not to applying the uncertainty principle only once, but to coherent alternation of the uncertainty principles accompanied by measurements proceeding internally. Sliding movement of an actin filament on a myosin molecule in the presence of ATP is just manifestation of the quantum phenomenon on how linear momentum could be conserved coherently both in space and in time. Since the uncertainty principle presumes measurement in one way or another, the coherent sliding movement of an actin filament pumped up by the interplay of the uncertainty principles on energy and momentum demonstrates an occurrence of the quantum coherence mediated by an alternated sequence of measurements proceeding internally.

6.2 Quantized Dissipation

The interplay between cohesive interaction and internal measurement in cell motility is, however, subtle in the face of quantum mechanics. Measurement is ubiquitous in the biological realm as in the form of signal detection, and at the same time fundamentally irreversible in making distinction between before and after the events. In contrast, the problem of measurement is intrinsic to quantum mechanics. This simplified overview raises a substantial question on how measurement, irreversibility and quantum mechanics could be related especially with regard to naturally occurring dissipative structures, including biological ones. We now address this question from the viewpoint that measurement is ubiquitous internally and updated at every finite time interval.^3,6

Let us suppose that an arbitrary material system, whether a molecule or a molecular organization, is involved in measuring its outside at every time interval of dt. Each internal measurement is accompanied with the energy de specified by the energy-time uncertainty principle

Since each measurement by the measuring system would disturb the outside to be measured energetically by the amount of de at every time interval dt, the energy flow w from the measuring system towards its outside turns out to satisfy

Implicit in the energy dissipation is the presence of energy sources to be dissipated on the part of the measuring system.

As the time interval of successive internal measurement decreases, the energy flow of dissipation would increase. Conversely, the time interval of internal measurement cannot be made arbitrarily small, otherwise there would be no energy sources to meet the associated dissipation.

One of the most ubiquitous sources of energy is gravitation. If the gravitation on the surface of the earth is the case, the gravitational force f_g acting upon the most stable fundamental unit of mass, that is, a hydrogen atom leads to f_g~10^-21erg/cm based upon the atomic mass unit of ~10^-24g and the gravitational acceleration on the surface of the earth ~980cm/s². Since the gravitational force is mediated by graviton propagating at light velocity c,²⁶ the hydrogen atom measuring the earth as a whole dissipates energy at the rate

The energy flow of dissipation due to internal measurement through the gravitation on the earth cannot become less than w_g because the hydrogen atom is the minimum mass unit available there. Of course, the hydrogen atom pulling the earth is pulled back by the earth. The dissipated energy is constantly compensated by the earth pulling the hydrogen atom.^21,26

On the other hand, quantum mechanics of the hydrogen atom measuring the earth yields that the measurement would proceed at every time interval of dt_g given by

because the energy flow of dissipation due to internal measurement updated at every interval of dtg yields w_g~h/(dt_g)². However, the internal measurement accompanied with energy dissipation caused by gravitation may be taken over if other internal measurement to be updated at the time interval smaller than dt_g would appear.

As a matter of fact, various naturally occurring dissipative structures on the earth are not exclusively of gravitational origin. Electrostatic and magnetic interaction are the likely possibility. In order to see the likelihood of natural dissipative structures that could occur through other than gravitational interaction, it would be asked to examine any possibility for internal measurement to be updated at the time interval smaller than dtg.

One such example of internal measurement facilitated by electrostatic interaction is available from an actin-myosin complex in the presence of ATP molecules as a fundamental functional unit of muscle contraction. Electrostatic interactions involved in the hydrolysis of an ATP molecule at the actomyosin complex are certainly responsible for both the generation of force and the occurrence of the sliding movement of the actin filament. In view of the observed fact that the generated force f_AM is about 2x10^-7dyne per myosin head^22,23 and the sliding velocity of the actin filament v_AM is about 4x10^-4cm/s,⁶ the rate of energy dissipation w_AM is found to be

The time interval dt_AM of successive internal measurement due to the electrostatic interactions leads to

which is certainly smaller than dt_g~5.8x10^-9s.

It is an undeniable fact that electrostatic and magnetic interaction are ubiquitous and far stronger than gravitational interaction under normal conditions realizable on the earth. Nonetheless, gravitational interaction can exert a significant influence upon the occurrence of internal measurement, or dissipative structures. Electrostatic interaction, though far stronger than gravitational one, is quite short-ranged in comparison because of the imposed condition of electric neutrality.

On the other hand, if internal measurement accompanied by its inevitable energy dissipation is to occur, both the source and the sink of energy would have to be prepared. Otherwise, internal measurement could not take place. If there is neither the source nor the sink to be prepared externally, this stipulation would result in that the time interval for measurement proceeding internally would effectively diverge, that is, quantum mechanics of a unitary transformation accompanied by no measurement. It is at this point where gravitational interaction enters.²⁶ Although it is very weak compared to electrostatic interaction, gravitational one can facilitate internal measurement by preparing both the energy source and sink for its completion in a self-consistent manner.²¹

Electrostatic interaction can take over gravitational interaction in framing internal measurement and the accompanied energy dissipation only when the rate of facilitated dissipation is quantized and the unit is made greater than the minimum dissipation rate specified by the gravitational interaction. Quantum mechanics of internal measurement,^3,6 which is necessarily irreversible, can materialize dissipative structures by means of electrostatic and magnetic interaction only when the associated dissipation is maintained above a certain minimum level.

Prerequisite to the appearance of dissipative structures through electrostatic and magnetic interaction is quantization of dissipation in the face of gravity. One implication of the quantization of dissipation is the homeostatic capacity of dissipation in maintaining its rate above the minimum quantum level. Unless such homeostatic capacity of approaching energy sources spontaneously from the inside is available, an indefinite sustenance of dissipation could not hold as facing and tolerating adverse conditions exerted temporarily from the outside. In fact, heterotrophic activity associated with biological phenomena ever since the origin of life on the earth about 3.8 billion years ago witnesses the case that dissipation is quantized in its rate.

7 Concluding Remarks

Emergent phenomena associated with biological organizations are methodo-

logically a subtle issue. If one employs external description of external measurement which has been proved in the endeavor for practicing objective and rigorous sciences, a great difficulty would come up with regard to the notion of variable duration. If it is asked, for instance, how natural selection could have originated, external description of external measurement practiced under the name of neo-Darwinism cannot cope with the question.²⁷ This is because the descriptive scheme is already based upon the notion of variable duration identified as natural selection. Questioning the origin of natural selection is methodologically discouraged or even prohibited there.

On the other hand, if one notes that external description of external measurement is not the only means for attaining descriptive objectivity of our experiences, external description of internal measurement will come up as an alternative that should deserve due attention. As a matter of fact, these two methodologies are by no means antagonistic with each other. External description of internal measurement duly transforms into external description of external measurement in the product because the consequence of internal measurement is externalized in the record and be globally measured externally. Emergent phenomena we experience in biology urges us to recognize that external description of internal measurement is a legitimate methodology for facing emergent novelty as much as external description of external measurement for invariant consistency.

In conclusion, external description of internal measurement is capable for identifying the nature of cohesive forces acting within biomolecules, organelles, cells, organs, tissues, organisms and even among their populations. Cell motility is certainly a concrete case exhibiting an interplay between internal measurement and cohesive interaction within the legitimate framework of quantum-mechanical phenomena.

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