Glossary

You may also be interested in the appendix about time measurement units

Absolute zero

The lowest possible temperature, at which a substance doesn't contain thermal energy

Acceleration

The rate of which a the speed of a moving object changes

Antiparticle

Every type of matter particle has a correspondent antiparticle. When a particles collides with a antiparticle, they annihilate each other, resulting only energy.

Atom

The basic unit of ordinary matter, containing a small nucleus (that contains protons and neutrons ) surrounded by electrons that move on orbits around it.

Big Bang

The singularity from the beginning of the Universe

Big Crunch

The singularity from the end of the Universe

Black Hole

A region of time-space from which nothing can escape, not even light, because of the immense gravity

Chandrasekkar limit

The maximum possible mass of a cold stable star ,over which it has to suffer a collapse forming a black hole

Cone of light

An area in time-space which contains the possible directions of the light beams that cross a given event

Coordinates

Numbers that specify the position of a point in space and time

Cosmological constant

A mathematical concept used by Einstein to give time-space an intrinsic tendency of expansion

Cosmology

The study of the universe

Energy conservation

Law of science affirming that mass(or equivalent energy) cannot be created or destroyed

Electric charge

A property of a particle according to which it can reject(or attract )other particles that have a charge of the same sign (or opposite sign)

Electromagnetic force

The force that appears between particles with electric charge, the second on the power scale of the 4 fundamental forces

Electron

A particle with a negative electric charge that moves around a nucleus of an atom, on a certain orbit.

The electroweak unifying energy

The energy over which the difference between the electromagnetic and weak interaction force disappears .

Elementary particle

A particle that is believed it cannot be divided into smaller particles

Event

A point in time-space, specified by its time and place

Event horizon

The limit of a black hole

Field

Something that exists everywhere in time and space, in opposition with a particle, that exists in a point at a certain moment.

Frequency

For a wave ,the number of complete cycles per second

Gamma rays

Electromagnetic waves with a short wave length ,produced in the radioactive disintegration or by colliding elementary particles

Generalized theory of relativity

Einstein's theory based on the idea that all laws of science must be the same for all observers, no matter how they move. It explains the gravitational force through the four-dimensional time-space curvature

Geodesic

The shortest road(or the longest) between 2 points

Imaginary time

The time measured using imaginary numbers

Light second(Light year)

The distance that light travels in 1 second(1 year)

Magnetic Field

The field that is responsible for the magnetic forces incorporated with the electric field into the electromagnetic field.

Mass

The quantity of matter of an object

The movement to red

The modification of a star's light , that is moving away from us, into red (because of the Doppler effect )

Neutron

An uncharged particle, very similar with the proton ,that represents almost have of the particles from a nucleus.

Neutron star

A cold star, sustained by the repulsion between its neutrons

The "no limit" condition

The idea sustaining that the universe is finite but without having limits

Nuclear fusion

The process in which 2 nucleuses collide and unite forming a single heavier nucleus

Nucleus

The central part of an atom , that is formed only out of protons and neutrons

Particle accelerator

A device that can accelerate moving charged particles, using electro-magnets ,thus giving them additional energy.

Phase

The position from the cycle of a wave at a certain moment

Photon

A quantum of light

Planck's quantum theory

The idea that light(or any classic particle) can be emitted or be absorbed only in discreet quanta , their energy being proportional with their frequency

Positron

Positive charged antiparticle of the electron

Primordial black hole

A black hole created in the very early phases of the universe

Protons

Electric charged particles that form approximately half of the particles from the nucleus of most atoms

Quantum

Indivisible unit in which waves can be emitted or absorbed

Quantum mechanics

The theory developed on Planck's quantum principle and on Heisenberg's uncertainty principle

Quark

An elementary charged particle that feels the strong interaction. Protons and neutrons are each formed of 3 quarks

Radar

A system that uses radio waves impulses to detect the position of an object ,measuring the needed time for a impulse to reach the object and to be reflected back.

Radioactivity

The spontaneous disintegration of a certain atomic nucleus into another

Singularity

A point of infinite space-time curvature

Singularity theorem

A theorem showing that a singularity has to exist in certain conditions- a specially , that the universe has to start with a singularity

Space dimension

Any of the 3 dimensions of time-space that refers to space (therefore any of the 3 dimensions except time )

Special relativity

Einstein's theory based on the idea that all laws of science must be the same for all observers, no matter what their speed is

Spin

A internal property of elementary particles ,bound with, but not identical with the usual rotation concept around an axis

Strong interaction

The most powerful fundamental force, which has the smallest action range. It maintains the quarks together with the protons and neutrons and maintains the protons and the neutrons together forming the atoms

Time-space

Four-dimensional space

Virtual particle

In quantum mechanics, a particle that cannot be direct detected, but it's effects can be measurable

Wave length

For a wave, the distance between 2 adjacent minimum points or 2 maximum adjacent points

Wave/particle dualism

Concept in quantum mechanics in which there isn't a distinction between waves and particles; particles can behave sometimes like waves and waves like particles

Weak interaction

A fundamental force that affects all matter particles, but doesn't affect the force carrying particles .It has a very short action range

Weight

The force exercised upon an object by the gravitational field. It is proportional with it's mass, but it's different from it

White dwarf

A cold stable star, sustained by the repulsion between electrons


Appendix-time measurement units

Atto-second

Basically the atto-second is the shortest interval of time that has a name! A movement inside the atom takes an atto-second,this being observed by scientists from The Technology University in Vienna during a laser experiment.

Pico-second

In water, for example, the link between hydrogen molecules brakes and rebuilds itself in a couple of pico seconds.

Microsecond

After a dynamite's fuse runs out, it takes 24 microseconds for it to explode. Another example: a bat can receive echoes at a rate of 2 microseconds.

Second

A human’s heart pulsation takes approximately 1 second. The rhythm of a heart is different at every person ,but normally there are between 50 and 100 beats per minute .

Hour

An average person consumes in an hour approximately 350.000 joules . In nature, the fastest reproduction takes an hour.

Day

The approximate time that the Earth needs to complete a full rotation around its axis. More precisely ,the rotation movement takes 23 hours, 56 minutes and 4 seconds.