Existing alongside the Marvel Universe are
other realities, aspects of which sometimes affect events
in the Marvel Universe. Some of these realties contain Earthlike
worlds and operate under natural laws similar to our own;
others are wildly dissimilar, and bear little resemblance
to the reality we know.
Most (if not all) of the other realities which
have thus far been encountered can be classified into one
of several categories, including:
ALTERNATE EARTHS: These realities contain
worlds that are very much like Earth, except that specific
events did not occur in quite the same way. There are two
types of alternate Earths - a Divergent Earth, in which
the history of events did not differ from the history of
our world until a particular event occurred, and a Parallel
Earth, in which no particular point of divergence can be
identified. It should be noted, however, that any Parallel
Earth could, in fact, turn out to be a Divergent Earth upon
further investigation.
ALIEN WORLDS: These realities contain
worlds that are clearly not Earth, though they may be Earthlike
in some respects. In most cases, these alien worlds will
be inhabited by humanoid (if not human) beings, but intelligent
life is certainly not a requisite for an alien world.
MICROVERSES: These realities are those,
which can be reached through a process of "shrinking."
When the space between atoms of physical matter is reduced
to a certain point, that matter may exit this reality altogether.
At one time, it was thought that microverse worlds existed
within the atoms of our own universe, but it seems now that
this is not the case. Rather, the access points between
dimensions are microscopic in size, not the worlds themselves.
Thus, it is possible to travel to the same "microverse"
on more than one occasion even if the journeys begin at
two different locations. (For more on the process of shrinking,
see Ant-Man.)
ASTRAL DIMENSIONS: These realities
do not contain physical matter, but ectoplasm, a quasi-material
substance, which cannot be totally defined. It is difficult
for physical beings to journey to Astral Dimensions. In
most cases, entry to an Astral Dimension is restricted to
a traveler's astral (or spirit) form, which is also composed
of ectoplasm.
INTERDIMENSIONAL SPACE: These realities
"between" realities tend not to have any recognizable
stability to their structure. Some are featureless and have
the appearance of unending space. Others contain bizarre
phenomena, which follow no consistent set of natural laws
that we can observe.
MYSTIC REALMS: These realities are
governed by natural laws which lend themselves to an interpretation
of "magic." While such worlds could, also be classified
as "alien," that designation is usually reserved
for worlds whose natural laws more clearly resemble Earth's.
ANTI-MATTER UNIVERSE: Only one reality
is known to be composed of anti-matter. The distinction
is worth drawing, since under normal conditions matter and
anti-matter will annihilate each other on contact, but in
all other respects the Negative Zone can be said to contain
simply alien worlds.
The list below contains important information
regarding the many alternate realities that have appeared
in the Marvel Universe up to 1985. The list includes some
entries which may not in fact be distinct realities of their
own, but may be a part of other alternate realities.
The set of all realities described in this
list, as well as others yet to be discovered is called the
Marvel Multiverse.
Specifically excluded from this list of alternate
dimensions are alternate time-lines such as those of Kang,
Killraven, the Guardians of the Galaxy, and more recently
The Age of Apocalypse. While various alternate futures contain
their own distinct realities, we deal here only with worlds
which are contemporary with the Marvel Universe and which
do not require time travel to reach.