Physical body

Physical body

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In physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

, a physical body or physical object (sometimes simply called a body or object) is a collection of mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...

es, taken to be one. For example, a cricket ball can be considered an object but the ball also consists of many particles (pieces of matter
Matter
Matter is a general term for the substance of which all physical objects consist. Typically, matter includes atoms and other particles which have mass. A common way of defining matter is as anything that has mass and occupies volume...

).

The common conception of physical objects includes that they have extension
Extension (metaphysics)
In metaphysics, extension is, roughly speaking, the property of "taking up space". René Descartes defines extension as the property of existing in more than one dimension. For Descartes, the primary characteristic of matter is extension, just as the primary characteristic of mind is consciousness...

 in the physical world
Universe
The Universe is commonly defined as the totality of everything that exists, including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Definitions and usage vary and similar terms include the cosmos, the world and nature...

, although there do exist theories
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...

 of quantum physics and cosmology
Cosmology
Cosmology is the discipline that deals with the nature of the Universe as a whole. Cosmologists seek to understand the origin, evolution, structure, and ultimate fate of the Universe at large, as well as the natural laws that keep it in order...

 which may challenge this.

In classical physics, mechanics, quantum physics, and cosmology



A physical body is an object which can be described by the theories of classical mechanics
Classical mechanics
In physics, classical mechanics is one of the two major sub-fields of mechanics, which is concerned with the set of physical laws describing the motion of bodies under the action of a system of forces...

, or quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...

, 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...

ed upon with physical instruments
Measuring instrument
In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the process of measurement gives a number relating the item...

. This includes the determination of trajectory
Trajectory
A trajectory is the path that a moving object follows through space as a function of time. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit—the path of a planet, an asteroid or a comet as it travels around a central mass...

 of position through space
Space
Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum...

, and in some cases of in space
Space
Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum...

, over a duration of time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

, as well as means to change these, by exerting force
Force
In physics, a force is any influence that causes an object to undergo a change in speed, a change in direction, or a change in shape. In other words, a force is that which can cause an object with mass to change its velocity , i.e., to accelerate, or which can cause a flexible object to deform...

s.

In classical physics
Classical physics
What "classical physics" refers to depends on the context. When discussing special relativity, it refers to the Newtonian physics which preceded relativity, i.e. the branches of physics based on principles developed before the rise of relativity and quantum mechanics...

, a physical body is a body with mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...

, not only energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...

, is three dimensional
Three-dimensional space
Three-dimensional space is a geometric 3-parameters model of the physical universe in which we live. These three dimensions are commonly called length, width, and depth , although any three directions can be chosen, provided that they do not lie in the same plane.In physics and mathematics, a...

 (extended
Extension (metaphysics)
In metaphysics, extension is, roughly speaking, the property of "taking up space". René Descartes defines extension as the property of existing in more than one dimension. For Descartes, the primary characteristic of matter is extension, just as the primary characteristic of mind is consciousness...

 in 3-dimension
Dimension
In physics and mathematics, the dimension of a space or object is informally defined as the minimum number of coordinates needed to specify any point within it. Thus a line has a dimension of one because only one coordinate is needed to specify a point on it...

s of space
Space
Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum...

), has a trajectory
Trajectory
A trajectory is the path that a moving object follows through space as a function of time. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit—the path of a planet, an asteroid or a comet as it travels around a central mass...

 of position and orientation in space
Space
Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum...

, and is lasting for some duration of time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

. It is the subject of study in an 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...

 and is the object referred to in a law of physics, or physical theory. It can be considered as a whole, but may be composed of a collection of smaller physical bodies, e.g. a weight, ball, proton
Proton
The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....

, or planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...

.

For instance, the force of gravity will accelerate a body if it is not supported, thus causing a change of its position (that is, it falls freely). However, it is not necessary for there to be forces present for an object position to change - only the rate of change of the object's position, that is, its velocity, will change under the influence of forces.

But in Quantum physics and Cosmology
Cosmology
Cosmology is the discipline that deals with the nature of the Universe as a whole. Cosmologists seek to understand the origin, evolution, structure, and ultimate fate of the Universe at large, as well as the natural laws that keep it in order...

, there is a debate as to whether some elementary particles are not bodies, but are mere points
Point (geometry)
In geometry, topology and related branches of mathematics a spatial point is a primitive notion upon which other concepts may be defined. In geometry, points are zero-dimensional; i.e., they do not have volume, area, length, or any other higher-dimensional analogue. In branches of mathematics...

 without extension
Extension (metaphysics)
In metaphysics, extension is, roughly speaking, the property of "taking up space". René Descartes defines extension as the property of existing in more than one dimension. For Descartes, the primary characteristic of matter is extension, just as the primary characteristic of mind is consciousness...

 in physical space within space-time, or are always extended in at least one dimension of space as in String theory
String theory
String theory is an active research framework in particle physics that attempts to reconcile quantum mechanics and general relativity. It is a contender for a theory of everything , a manner of describing the known fundamental forces and matter in a mathematically complete system...

 or M theory.

In psychology


In some branches of psychology
Psychology
Psychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...

, depending on school of thought, a physical body is a physical object with physical properties, as compared to mental objects. In (reductionistic) behaviorism
Behaviorism
Behaviorism , also called the learning perspective , is a philosophy of psychology based on the proposition that all things that organisms do—including acting, thinking, and feeling—can and should be regarded as behaviors, and that psychological disorders are best treated by altering behavior...

, a physical body and its properties are the (only) meaningful objects of study.
While in the modern day behavioral psychotherapy it is still only the means for goal oriented behavior modifications, in Body Psychotherapy
Body Psychotherapy
Body psychotherapy, also referred to as body-oriented psychotherapy and somatic psychology, is a significant branch of psychotherapy, with origins in the work of Pierre Janet, Sigmund Freud and particularly Wilhelm Reich....

 it is not a means only anymore, but its felt sense is a goal of its own. In cognitive psychology
Cognitive psychology
Cognitive psychology is a subdiscipline of psychology exploring internal mental processes.It is the study of how people perceive, remember, think, speak, and solve problems.Cognitive psychology differs from previous psychological approaches in two key ways....

, physical bodies as they occur in biology
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...

 are studied in order to understand the mind
Mind
The concept of mind is understood in many different ways by many different traditions, ranging from panpsychism and animism to traditional and organized religious views, as well as secular and materialist philosophies. Most agree that minds are constituted by conscious experience and intelligent...

, which may not be a physical body, as in functionalist
Functionalism (philosophy of mind)
Functionalism is a theory of the mind in contemporary philosophy, developed largely as an alternative to both the identity theory of mind and behaviourism. Its core idea is that mental states are constituted solely by their functional role — that is, they are causal relations to other mental...

 schools of thought.

In philosophy


A physical body is an enduring object that exists throughout a particular trajectory
Trajectory
A trajectory is the path that a moving object follows through space as a function of time. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit—the path of a planet, an asteroid or a comet as it travels around a central mass...

 of space
Space
Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum...

 and orientation over a particular duration of time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

, and which is extended
Extension (metaphysics)
In metaphysics, extension is, roughly speaking, the property of "taking up space". René Descartes defines extension as the property of existing in more than one dimension. For Descartes, the primary characteristic of matter is extension, just as the primary characteristic of mind is consciousness...

 in the world of physical space, e.g. as studied by physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

. This contrasts with abstract object
Abstract object
An abstract object is an object which does not exist at any particular time or place, but rather exists as a type of thing . In philosophy, an important distinction is whether an object is considered abstract or concrete. Abstract objects are sometimes called abstracta An abstract object is an...

s such as mathematical object
Mathematical object
In mathematics and the philosophy of mathematics, a mathematical object is an abstract object arising in mathematics.Commonly encountered mathematical objects include numbers, permutations, partitions, matrices, sets, functions, and relations...

s which do not exist at any particular time or place.
Examples are a cloud
Cloud
A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...

, a human body
Human body
The human body is the entire structure of a human organism, and consists of a head, neck, torso, two arms and two legs.By the time the human reaches adulthood, the body consists of close to 100 trillion cells, the basic unit of life...

, a weight, a billard ball, a table, or a proton
Proton
The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....

. This is contrasted with abstract object
Abstract object
An abstract object is an object which does not exist at any particular time or place, but rather exists as a type of thing . In philosophy, an important distinction is whether an object is considered abstract or concrete. Abstract objects are sometimes called abstracta An abstract object is an...

s such as mental objects, which exist in the mental world
Mental world
The mental world is an ontological category in metaphysics, populated by nonmaterial mental objects, without physical extension contrasted with the physical world of space and time populated with physical objects, or Plato's world of ideals populated, in part, with mathematical...

, and mathematical object
Mathematical object
In mathematics and the philosophy of mathematics, a mathematical object is an abstract object arising in mathematics.Commonly encountered mathematical objects include numbers, permutations, partitions, matrices, sets, functions, and relations...

s. Other examples that are not physical bodies are emotions, the concept of "justice
Justice
Justice is a concept of moral rightness based on ethics, rationality, law, natural law, religion, or equity, along with the punishment of the breach of said ethics; justice is the act of being just and/or fair.-Concept of justice:...

", a feeling of hatred, or the number
Number
A number is a mathematical object used to count and measure. In mathematics, the definition of number has been extended over the years to include such numbers as zero, negative numbers, rational numbers, irrational numbers, and complex numbers....

 "3". In some philosophies, like the Idealism
Idealism
In philosophy, idealism is the family of views which assert that reality, or reality as we can know it, is fundamentally mental, mentally constructed, or otherwise immaterial. Epistemologically, idealism manifests as a skepticism about the possibility of knowing any mind-independent thing...

 of George Berkeley
George Berkeley
George Berkeley , also known as Bishop Berkeley , was an Irish philosopher whose primary achievement was the advancement of a theory he called "immaterialism"...

, a physical body is a mental object, but still has extension in the space of a visual field.

In new age philosophy, mysticism and religion


In some systems of mysticism
Mysticism
Mysticism is the knowledge of, and especially the personal experience of, states of consciousness, i.e. levels of being, beyond normal human perception, including experience and even communion with a supreme being.-Classical origins:...

, such as Theosophy
Theosophy
Theosophy, in its modern presentation, is a spiritual philosophy developed since the late 19th century. Its major themes were originally described mainly by Helena Blavatsky , co-founder of the Theosophical Society...

, the physical body is understood as the last of several progressively denser "vehicles of consciousness
Consciousness
Consciousness is a term that refers to the relationship between the mind and the world with which it interacts. It has been defined as: subjectivity, awareness, the ability to experience or to feel, wakefulness, having a sense of selfhood, and the executive control system of the mind...

". In Blavatskyian Theosophy it is called by the Vedantic
Vedanta
Vedānta was originally a word used in Hindu philosophy as a synonym for that part of the Veda texts known also as the Upanishads. The name is a morphophonological form of Veda-anta = "Veda-end" = "the appendix to the Vedic hymns." It is also speculated that "Vedānta" means "the purpose or goal...

 name sthula sarira - "gross body" - and distinguished from the linga sarira, the "subtle body
Subtle body
A subtle body is one of a series of psycho-spiritual constituents of living beings, according to various esoteric, occult, and mystical teachings...

" or astral double. In C. W. Leadbeater and Alice Bailey
Alice Bailey
Alice Ann Bailey , known as Alice A. Bailey or AAB to her followers, was an influential writer and theosophist in what she termed "Ageless Wisdom". This included occult teachings, "esoteric" psychology and healing, astrological and other philosophic and religious themes...

, the physical body is distinguished from the etheric body
Etheric body
The etheric body, ether-body, æther body, a name given by neo-Theosophy to a supposed vital body or subtle body propounded in esoteric philosophies as the first or lowest layer in the "human energy field" or aura...

, which serves as its "blueprint", and structures of the etheric body
Etheric body
The etheric body, ether-body, æther body, a name given by neo-Theosophy to a supposed vital body or subtle body propounded in esoteric philosophies as the first or lowest layer in the "human energy field" or aura...

, such as chakra
Chakra
Chakra is a concept originating in Hindu texts, featured in tantric and yogic traditions of Hinduism and Buddhism. Its name derives from the Sanskrit word for "wheel" or "turning" .Chakra is a concept referring to wheel-like vortices...

s, are mirrored in the main gland
Gland
A gland is an organ in an animal's body that synthesizes a substance for release of substances such as hormones or breast milk, often into the bloodstream or into cavities inside the body or its outer surface .- Types :...

s and nerve ganglia
Ganglion
In anatomy, a ganglion is a biological tissue mass, most commonly a mass of nerve cell bodies. Cells found in a ganglion are called ganglion cells, though this term is also sometimes used to refer specifically to retinal ganglion cells....

 of the physical body.

In some religion
Religion
Religion is a collection of cultural systems, belief systems, and worldviews that establishes symbols that relate humanity to spirituality and, sometimes, to moral values. Many religions have narratives, symbols, traditions and sacred histories that are intended to give meaning to life or to...

s, and in some new age
New Age
The New Age movement is a Western spiritual movement that developed in the second half of the 20th century. Its central precepts have been described as "drawing on both Eastern and Western spiritual and metaphysical traditions and then infusing them with influences from self-help and motivational...

 philosophies, a physical body is contrasted with the self
Self (philosophy)
The philosophy of self defines the essential qualities that make one person distinct from all others. There have been numerous approaches to defining these qualities. The self is the idea of a unified being which is the source of consciousness. Moreover, this self is the agent responsible for the...

, mind
Mind
The concept of mind is understood in many different ways by many different traditions, ranging from panpsychism and animism to traditional and organized religious views, as well as secular and materialist philosophies. Most agree that minds are constituted by conscious experience and intelligent...

, spirit
Spirit
The English word spirit has many differing meanings and connotations, most of them relating to a non-corporeal substance contrasted with the material body.The spirit of a living thing usually refers to or explains its consciousness.The notions of a person's "spirit" and "soul" often also overlap,...

, soul
Soul
A soul in certain spiritual, philosophical, and psychological traditions is the incorporeal essence of a person or living thing or object. Many philosophical and spiritual systems teach that humans have souls, and others teach that all living things and even inanimate objects have souls. The...

, or astral projection
Astral projection
Astral projection is an interpretation of out-of-body experience that assumes the existence of an "astral body" separate from the physical body and capable of traveling outside it...

, and sometimes with an heavenly body
Heavenly Body
is a yaoi manga anthology by Takashi Kanzaki and published by Daitosha. It is licensed in English by Aurora Publishing, which released the manga in August 2008.-Reception:...

. It is ephemeral
Ephemeral
Ephemeral things are transitory, existing only briefly. Typically the term is used to describe objects found in nature, although it can describe a wide range of things....

 in time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

, not eternal
Eternity
While in the popular mind, eternity often simply means existence for a limitless amount of time, many have used it to refer to a timeless existence altogether outside time. By contrast, infinite temporal existence is then called sempiternity. Something eternal exists outside time; by contrast,...

. It may be what houses the spirit or soul, and it is what is left behind in an astral projection
Astral projection
Astral projection is an interpretation of out-of-body experience that assumes the existence of an "astral body" separate from the physical body and capable of traveling outside it...

, or ascention
Wiktionary
Wiktionary is a multilingual, web-based project to create a free content dictionary, available in 158 languages...

 into heaven
Heaven
Heaven, the Heavens or Seven Heavens, is a common religious cosmological or metaphysical term for the physical or transcendent place from which heavenly beings originate, are enthroned or inhabit...

. A physical body exists on earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

, not in heaven
Heaven
Heaven, the Heavens or Seven Heavens, is a common religious cosmological or metaphysical term for the physical or transcendent place from which heavenly beings originate, are enthroned or inhabit...

, not in the astral world, nor in the aether
Aether (classical element)
According to ancient and medieval science aether , also spelled æther or ether, is the material that fills the region of the universe above the terrestrial sphere.-Mythological origins:...

.

See also

  • Deformable body
  • Rigid body
    Rigid body
    In physics, a rigid body is an idealization of a solid body of finite size in which deformation is neglected. In other words, the distance between any two given points of a rigid body remains constant in time regardless of external forces exerted on it...

  • Human body
    Human body
    The human body is the entire structure of a human organism, and consists of a head, neck, torso, two arms and two legs.By the time the human reaches adulthood, the body consists of close to 100 trillion cells, the basic unit of life...

  • Object-Oriented Programming
    Object-oriented programming
    Object-oriented programming is a programming paradigm using "objects" – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs. Programming techniques may include features such as data abstraction,...