Phenomenology (science)
Encyclopedia
The term phenomenology in science
Science
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...

 is used to describe a body of knowledge that relates empirical observations
Experiment
An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...

 of phenomena
Phenomenon
A phenomenon , plural phenomena, is any observable occurrence. Phenomena are often, but not always, understood as 'appearances' or 'experiences'...

 to each other, in a way that is consistent with fundamental theory
Theory
The English word theory was derived from a technical term in Ancient Greek philosophy. The word theoria, , meant "a looking at, viewing, beholding", and referring to contemplation or speculation, as opposed to action...

, but is not directly derived from theory. For example, we find the following definition in the Concise Dictionary of Physics:
Phenomenological Theory. A theory that expresses mathematically the results of observed phenomena without paying detailed attention to their fundamental significance.


The name is derived from phenomenon
Phenomenon
A phenomenon , plural phenomena, is any observable occurrence. Phenomena are often, but not always, understood as 'appearances' or 'experiences'...

 (from Greek φαινόμενoν, pl. φαινόμενα - phenomena and -λογία - -logia, translated as "study of" or "research"), which is any occurrence that is observable.

Phenomenology in physical sciences

There are cases in physics when it is not possible to derive a theory for describing observed results from the known first principles (such as Newton's laws of motion
Newton's laws of motion
Newton's laws of motion are three physical laws that form the basis for classical mechanics. They describe the relationship between the forces acting on a body and its motion due to those forces...

 or Maxwell's equations
Maxwell's equations
Maxwell's equations are a set of partial differential equations that, together with the Lorentz force law, form the foundation of classical electrodynamics, classical optics, and electric circuits. These fields in turn underlie modern electrical and communications technologies.Maxwell's equations...

 of electromagnetism). There may be several reasons for this. For example, the underlying theory is not yet discovered, or the mathematics to describe the observations is too complex. In these cases sometimes simple algebra
Algebra
Algebra is the branch of mathematics concerning the study of the rules of operations and relations, and the constructions and concepts arising from them, including terms, polynomials, equations and algebraic structures...

ic expressions may be used to model the observations or experimental results. The algebraic model is then used to make predictions about the results of other observations or experiments. If the predictions made by the algebraic model are sufficiently accurate, they are often adopted by the scientific community despite the fact that the algebraic expressions themselves cannot be (or have not yet been) derived from the fundamental theory of that domain of knowledge.

The boundaries between theory
Theory
The English word theory was derived from a technical term in Ancient Greek philosophy. The word theoria, , meant "a looking at, viewing, beholding", and referring to contemplation or speculation, as opposed to action...

 and phenomenology, and between phenomenology and experiment
Experiment
An experiment is a methodical procedure carried out with the goal of verifying, falsifying, or establishing the validity of a hypothesis. Experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results...

, are fuzzy. Some philosophers of science
Philosophy of science
The philosophy of science is concerned with the assumptions, foundations, methods and implications of science. It is also concerned with the use and merit of science and sometimes overlaps metaphysics and epistemology by exploring whether scientific results are actually a study of truth...

, and in particular Nancy Cartwright
Nancy Cartwright (philosopher)
Nancy Cartwright FBA is a professor of philosophy at the London School of Economics and the University of California at San Diego, and a recipient of a MacArthur Fellowship...

 argue that any fundamental laws of Nature are merely phenomenological generalizations.

Examples in physics

The examples below are in chronological order.
  • Second law of thermodynamics
    Second law of thermodynamics
    The second law of thermodynamics is an expression of the tendency that over time, differences in temperature, pressure, and chemical potential equilibrate in an isolated physical system. From the state of thermodynamic equilibrium, the law deduced the principle of the increase of entropy and...

    : Prior to the development of statistical mechanics
    Statistical mechanics
    Statistical mechanics or statistical thermodynamicsThe terms statistical mechanics and statistical thermodynamics are used interchangeably...

     by Ludwig Boltzmann
    Ludwig Boltzmann
    Ludwig Eduard Boltzmann was an Austrian physicist famous for his founding contributions in the fields of statistical mechanics and statistical thermodynamics...

     (1896), this law was phenomenological. For instance, spontaneous net flow of heat from a lower temperature to a higher temperature had never been observed and this fact served as the basis of the second law.
  • Rutherford model
    Rutherford model
    The Rutherford model or planetary model is a model of the atom devised by Ernest Rutherford. Rutherford directed the famous Geiger-Marsden experiment in 1909, which suggested on Rutherford's 1911 analysis that the so-called "plum pudding model" of J. J. Thomson of the atom was incorrect...

     also known as planetary model (1911) describes the structure of an atom based on the experimental results. It has a number of essential modern features, including a relatively high central charge concentrated into a very small volume in comparison to the rest of the atom. It resembles the planetary system, a known physical object larger by several orders of magnitude. It was superseded in 1913 by the Bohr model
    Bohr model
    In atomic physics, the Bohr model, introduced by Niels Bohr in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar in structure to the solar system, but with electrostatic forces providing attraction,...

    , which used some of the early quantum mechanical results to give locational structure to the behavior of the orbiting electrons, confining them to certain circular (and later elliptical) orbits.
  • Landau theory
    Landau theory
    Landau theory in physics was introduced by Lev Landau in an attempt to formulate a general theory of second-order phase transitions. He was motivated to suggest that the free energy of any system should obey two conditions: that the free energy is analytic, and that it obeys the symmetry of the...

     of second order phase transition
    Phase transition
    A phase transition is the transformation of a thermodynamic system from one phase or state of matter to another.A phase of a thermodynamic system and the states of matter have uniform physical properties....

    s (1936).
  • Bloch equations
    Bloch equations
    In physics and chemistry, specifically in NMR or MRI , or ESR the Bloch equations are a set of macroscopic equations that are used to calculate the nuclear magnetization M = as a function of time when relaxation times T1 and T2 are present...

     (1946).
  • Ginzburg-Landau theory
    Ginzburg-Landau theory
    In physics, Ginzburg–Landau theory, named after Vitaly Lazarevich Ginzburg and Lev Landau, is a mathematical theory used to model superconductivity. It does not purport to explain the microscopic mechanisms giving rise to superconductivity...

     of superconductivity
    Superconductivity
    Superconductivity is a phenomenon of exactly zero electrical resistance occurring in certain materials below a characteristic temperature. It was discovered by Heike Kamerlingh Onnes on April 8, 1911 in Leiden. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum...

     (1950).

Phenomenology in social statistics

In the science of statistics
Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....

, the collection of quantifiable data from people involves a phenomenological step. Namely, in order to obtain that data, survey questions must be designed to collect measurable responses that are categorized in a logically sound and practical way, such that the form in which the questions are asked does not bias
Bias
Bias is an inclination to present or hold a partial perspective at the expense of alternatives. Bias can come in many forms.-In judgement and decision making:...

 the results. If this is not done, data distortions due to question-wording effects (response error) occur, and the data obtained may have no validity at all, because observations that do not have the same meaning (it would be like "adding up apples and pears") are counted up A prerequisite of a good survey is that all respondents are really able to give a definite and unambiguous answer to the questions, and that they understand what is asked of them in the same way. One could, for example, ask farmers, "How much risk do you run on your farm?" with a scale of response options ranging, for example, from "a lot of risk" to "no risk". But this yields quantitatively meaningless data that is not objective, since the interpretations of "how much risk" by farmers could focus, for example, on the number, size, frequency, severity, or consequence of risks, and each farmer will have his own idiosyncratic idea about that. All farmers may suffer, for example, from a lack of rainfall, but some will personally consider it a large risk, others a low risk, and some not a risk at all. Furthermore, in actually asking the questions of respondents and subsequently coding
Coding
Coding may refer to:* Channel coding in coding theory* Line coding* Computer programming, the process of designing, writing, testing, debugging / troubleshooting, and maintaining the source code of computer programs...

 the responses to numerical values, a technique must be found to ensure that no misinterpretation occurs of a type that would lead to errors. In other words, in designing the survey instrument, the researcher must somehow find a satisfactory "bridge" of meaning between the logical and practical requirements of the survey statistician, a statistical classification scheme, the awareness of respondents and the processors of the raw data. Finding this "bridge" involves an abstraction process that necessarily goes beyond logical inference, theory and experiment and involves an element of "art", because it must establish an appropriate connection between the language used, the intersubjective interactions between the surveyor and the respondent, and how respondents and those who process the data construct the meaning of what is being asked of them. For this cognitive process, it is impossible to provide a standard procedure that will always work, only "rules of thumb"; it requires a "practical" human insight.

See also

  • Empirical relationship
    Empirical relationship
    In science, an empirical relationship is one based solely on observation rather than theory. An empirical relationship requires only confirmatory data irrespective of theoretical basis. Sometimes theoretical explanations for what were initially empirical relationships are found, in which case the...

  • Heterophenomenology
    Heterophenomenology
    Heterophenomenology is a term coined by Daniel Dennett to describe an explicitly third-person, scientific approach to the study of consciousness and other mental phenomena...

  • Particle physics phenomenology
    Particle physics phenomenology
    Particle physics phenomenology is the part of theoretical particle physics that deals with the application of theory to high-energy particle physics experiments. Within the Standard Model, phenomenology is the calculating of detailed predictions for experiments, usually at high precision...

  • Phenomenology (philosophy)
  • Phenomenology (psychology)
    Phenomenology (psychology)
    Phenomenology is an approach to psychological subject matter that has its roots in the philosophical work of Edmund Husserl. Early phenomenologists such as Husserl, Jean-Paul Sartre, and Maurice Merleau-Ponty conducted their own psychological investigations in the early 20th century...

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