Source Word
adjunction
Noun
countable
uncountable
Japanese Meaning
何かを結合する行為、または結合されたもの / （法律）個人の所有財産が他者の所有財産に加わること、または統合される状態
Sense（3）
(category
theory)
Given
a
pair
of
categories
𝒞
and
𝒟:
an
anti-parallel
pair
of
functors
F:𝒞→𝒟
and
G:𝒟→𝒞
and
a
natural
transformation
𝜂:
mbox
id_C→GF
called
“unit”
such
that
for
any
object
A∈𝒞,
for
any
object
B∈𝒟,
and
for
any
morphism
f:A→GB,
there
is
a
unique
morphism
g:FA→B
such
that
Gg∘𝜂_A=f.
(Note:
there
is
another
natural
transformation
called
“counit”
as
well
but
its
existence
may
be
derived
by
theorem.)
The
pair
of
functors
express
a
similarity
between
the
pair
of
categories
which
is
weaker
than
that
of
an
equivalence
of
categories.
（ plural ）
