The internal measurement refers to the

quantum measurement In quantum physics, a measurement is the testing or manipulation of a physical system to yield a numerical result. The predictions that quantum physics makes are in general probabilistic. The mathematical tools for making predictions about what ...

realized by the endo-

observer An observer is one who engages in observation or in watching an experiment. Observer may also refer to: Computer science and information theory * In information theory, any system which receives information from an object * State observer in con ...

. Quantum measurement represents the action of a

measuring device A measuring instrument is a device to measure a physical quantity. In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Establis ...

on the measured system. When the measuring device is a part of measured system, the measurement proceeds internally in relation to the whole system. This theory was introduced by Koichiro Matsuno and developed by Yukio-Pegio Gunji. They further expanded the original ideas of Robert Rosen and Howard Pattee on the quantum measurement in living systems viewed as natural internal observers that belong to the same scale of the observed objects. According to Matsuno, the internal measurement is accompanied by the redistribution of probabilities that leave them entangled in accordance with the

many-worlds interpretation The many-worlds interpretation (MWI) is an interpretation of quantum mechanics that asserts that the universal wavefunction is objectively real, and that there is no wave function collapse. This implies that all possible outcomes of quantum me ...

quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, ...

by Everett. However, this form of quantum entanglement does not survive in the external measurement in which the mapping to real numbers takes place and the result is revealed in the classical time-space as the

Copenhagen interpretation The Copenhagen interpretation is a collection of views about the meaning of quantum mechanics, principally attributed to Niels Bohr and Werner Heisenberg. It is one of the oldest of numerous proposed interpretations of quantum mechanics, as featu ...

suggests. This means that the internal measurement concept unifies the alternative

interpretations of quantum mechanics An interpretation of quantum mechanics is an attempt to explain how the mathematical theory of quantum mechanics might correspond to experienced reality. Although quantum mechanics has held up to rigorous and extremely precise tests in an extraord ...

Internal measurement and theoretical biology

The concept of internal measurement is important for

theoretical biology Mathematical and theoretical biology, or biomathematics, is a branch of biology which employs theoretical analysis, mathematical models and abstractions of the living organisms to investigate the principles that govern the structure, development a ...

living organisms In biology, an organism () is any life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multicellular o ...

can be regarded as endo-observers having their internal

self-referential encoding Self-referential encoding is a method of organizing information in one's memory in which one interprets incoming information in relation to oneself, using one's self-concept as a background.Rogers, T. B., Kuiper, N. A., & Kirker, W. S. (1977). Sel ...

. The internal measurement leads to an

iterative Iteration is the repetition of a process in order to generate a (possibly unbounded) sequence of outcomes. Each repetition of the process is a single iteration, and the outcome of each iteration is then the starting point of the next iteration. ...

recursive Recursion (adjective: ''recursive'') occurs when a thing is defined in terms of itself or of its type. Recursion is used in a variety of disciplines ranging from linguistics to logic. The most common application of recursion is in mathematics ...

process which appears as the

development Development or developing may refer to: Arts *Development hell, when a project is stuck in development *Filmmaking, development phase, including finance and budgeting *Development (music), the process thematic material is reshaped *Photographi ...

and

evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

of the system where any solution is destined to be relative. The evolutionary increase of complexity becomes possible when the

genotype The genotype of an organism is its complete set of genetic material. Genotype can also be used to refer to the alleles or variants an individual carries in a particular gene or genetic location. The number of alleles an individual can have in a ...

emerges as a system distinct from the

phenotype In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ...

and embedded into it, which separates energy-degenerate rate-independent genetic symbols from the rate-dependent dynamics of construction that they control. Evolution in this concept, which is related to

autopoiesis The term autopoiesis () refers to a system capable of producing and maintaining itself by creating its own parts. The term was introduced in the 1972 publication '' Autopoiesis and Cognition: The Realization of the Living'' by Chilean biologist ...

, becomes its own cause, a universal property of our world.

Internal measurement and the problem of self

The

self The self is an individual as the object of that individual’s own reflective consciousness. Since the ''self'' is a reference by a subject to the same subject, this reference is necessarily subjective. The sense of having a self—or ''selfhood ...

can be attributed to the internal quantum state with entangled probabilities. This entanglement can be held for prolonged times in the systems with low dissipation without demolition. According to Matsuno, organisms exploit thermodynamic gradients by acting as

heat engines In thermodynamics and engineering, a heat engine is a system that converts heat to mechanical energy, which can then be used to do mechanical work. It does this by bringing a working substance from a higher state temperature to a lower state t ...

to drastically reduce the effective temperature within macromolecular complexes which can potentially provide the maintenance of long-living

coherent states In physics, specifically in quantum mechanics, a coherent state is the specific quantum state of the quantum harmonic oscillator, often described as a state which has dynamics most closely resembling the oscillatory behavior of a classical harmo ...

in the

microtubules Microtubules are polymers of tubulin that form part of the cytoskeleton and provide structure and shape to eukaryotic cells. Microtubules can be as long as 50 micrometres, as wide as 23 to 27 nm and have an inner diameter between 11 an ...

nervous system In biology, the nervous system is the highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body. The nervous system detects environmental changes th ...

. The concept of internal measurement develops the ideas of Schrödinger who suggested in '' "What is life?"'' that the nature of the self is quantum mechanical, i.e. the self is attributed to an internal state beyond quantum reduction, which generates emergent events by applying quantum reduction externally and observing it.

References

{{Reflist Philosophical theories Measurement

Internal measurement and theoretical biology

Internal measurement and the problem of self

See also

References