In the ''
Star Trek
''Star Trek'' is an American science fiction media franchise created by Gene Roddenberry, which began with the Star Trek: The Original Series, series of the same name and became a worldwide Popular culture, pop-culture Cultural influence of ...
''
fictional universe
A fictional universe, also known as an imagined universe or a constructed universe, is the internally consistent fictional setting used in a narrative or a work of art. This concept is most commonly associated with works of fantasy and scie ...
, dilithium is a
fictional material that serves as a controlling agent in the matter-
antimatter
In modern physics, antimatter is defined as matter composed of the antiparticles (or "partners") of the corresponding subatomic particle, particles in "ordinary" matter, and can be thought of as matter with reversed charge and parity, or go ...
reactors. In
the original series, dilithium crystals were rare and could not be
replicated, making the search for them a recurring plot element. According to a periodic table shown during a ''
Next Generation'' episode, it has the
atomic number
The atomic number or nuclear charge number (symbol ''Z'') of a chemical element is the charge number of its atomic nucleus. For ordinary nuclei composed of protons and neutrons, this is equal to the proton number (''n''p) or the number of pro ...
87 (which in reality belongs to
francium
Francium is a chemical element; it has symbol Fr and atomic number 87. It is extremely radioactive; its most stable isotope, francium-223 (originally called '' actinium K'' after the natural decay chain in which it appears), has a half-l ...
), and the
chemical symbol
Chemical symbols are the abbreviations used in chemistry, mainly for chemical elements; but also for functional groups, chemical compounds, and other entities. Element symbols for chemical elements, also known as atomic symbols, normally consist ...
Dt.
In reality,
dilithium (Li) is a
molecule
A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...
composed of two
covalently bonded lithium atoms which exists naturally in gaseous lithium.
Dilithium is depicted as a valuable, extremely hard
crystal
A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macros ...
line mineral that occurs naturally on some planets.
Use
The fictional properties of the material in the authors' guide ''
Star Trek: The Next Generation Technical Manual'' (1991) explain it as uniquely suited to contain and regulate the annihilation reaction of matter and antimatter in a starship's warp core: In a high-frequency electromagnetic field,
eddy currents are induced in the dilithium crystal structure, which keep charged particles away from the crystal lattice. This prevents it from coming in contact with
antimatter
In modern physics, antimatter is defined as matter composed of the antiparticles (or "partners") of the corresponding subatomic particle, particles in "ordinary" matter, and can be thought of as matter with reversed charge and parity, or go ...
when so energized, hence never
annihilating, because the antimatter particles never actually touch it.
In the original series, dilithium crystals were rare, and crystals made by
replicator were unsatisfactory for use in warp drives.
Hence story lines based on the need for natural dilithium crystals for interstellar travel – much like real-world equivalents such as oil – made deposits of this material a highly contested resource between fictional factions in the stories, and as such, dilithium crystals have been used by writers to introduce interstellar conflict more than all other reasons combined.
As depicted on the show, the streams of
matter
In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic pa ...
(
deuterium
Deuterium (hydrogen-2, symbol H or D, also known as heavy hydrogen) is one of two stable isotopes of hydrogen; the other is protium, or hydrogen-1, H. The deuterium nucleus (deuteron) contains one proton and one neutron, whereas the far more c ...
gas) and
antimatter
In modern physics, antimatter is defined as matter composed of the antiparticles (or "partners") of the corresponding subatomic particle, particles in "ordinary" matter, and can be thought of as matter with reversed charge and parity, or go ...
(anti-deuterium) directed into crystallized dilithium are unbalanced – there is usually much more matter in the stream than antimatter. The annihilation reaction heats the excess deuterium gas, which produces
plasma for the
nacelles and allows
faster than light
Faster-than-light (superluminal or supercausal) travel and communication are the conjectural propagation of matter or information faster than the speed of light in vacuum (). The special theory of relativity implies that only particles with zero ...
travel.
In addition,
film set
A set is artificially constructed scenery used in film and television. In the last two cases there are many reasons to build or use a set instead of travelling to a real location, such as budget, time, the need to control the environment, or the ...
s representing the crawl-spaces for the inner workings of starships tend to be depicted as adjacent to the "EPS" conduits that channel plasma to critical ships' internal systems.
Fictional properties
Dilithium is a member of a so-called "hypersonic" series of elements, according to a fictional periodic table graphic presented in episodes of ''Star Trek: The Next Generation''
and ''
Star Trek: Deep Space Nine'' (1993–1999). The material is suspected by its fictional users of existing in more dimensions than the conventional three + one dimensions of
spacetime
In physics, spacetime, also called the space-time continuum, is a mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams are useful in visualiz ...
, and that this somehow is related to its unconventional or paradoxical properties.
The dilithium mineral structure is 2(5)6 dilithium 2(:)l diallo
silicate
A silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is also used ...
1:9:1 hepto
ferranide, according to the authors' guide ''
Star Trek: The Next Generation Technical Manual'' (1991).
In respect of the fictional
replication technology used as background for the ''Star Trek'' universe, although low-quality artificial crystals can be grown or replicated, the synthetic dilithium crystals can only regulate a limited amount of power without fragmenting, and are largely unsuitable for use in warp drives.
See also
*
List of ''Star Trek'' materials
Footnotes
References
External links
*
"The Mineralogy of ''Star Trek''"
{{Star Trek
Fictional materials
Star Trek terminology