<s>
A	O
ternary	O
computer	O
,	O
also	O
called	O
trinary	B-Device
computer	I-Device
,	O
is	O
one	O
that	O
uses	O
ternary	B-Language
logic	I-Language
(	O
i.e.	O
,	O
base	B-Algorithm
3	I-Algorithm
)	O
instead	O
of	O
the	O
more	O
common	O
binary	O
system	O
(	O
i.e.	O
,	O
base	O
2	O
)	O
in	O
its	O
calculations	O
.	O
</s>
<s>
This	O
means	O
it	O
uses	O
trits	B-Algorithm
(	O
instead	O
of	O
bits	O
,	O
as	O
most	O
computers	O
do	O
)	O
.	O
</s>
<s>
System	O
States	O
Unbalanced	O
ternary	O
0	O
1	O
2	O
Fractional	O
unbalanced	O
ternary	O
0	O
1	O
Balanced	B-Algorithm
ternary	I-Algorithm
−1	O
0	O
1	O
Unknown-state	O
logic	O
F	O
?	O
</s>
<s>
Ternary	O
quantum	O
computers	O
use	O
qutrits	B-Device
rather	O
than	O
trits	B-Algorithm
.	O
</s>
<s>
A	O
qutrit	B-Device
is	O
a	O
quantum	O
state	O
that	O
is	O
a	O
complex	O
unit	O
vector	O
in	O
three	O
dimensions	O
,	O
which	O
can	O
be	O
written	O
as	O
in	O
the	O
bra-ket	O
notation	O
.	O
</s>
<s>
One	O
early	O
calculating	O
machine	O
,	O
built	O
entirely	O
from	O
wood	O
by	O
Thomas	O
Fowler	O
in	O
1840	O
,	O
operated	O
in	O
balanced	B-Algorithm
ternary	I-Algorithm
.	O
</s>
<s>
The	O
first	O
modern	O
,	O
electronic	O
ternary	O
computer	O
,	O
Setun	B-Device
,	O
was	O
built	O
in	O
1958	O
in	O
the	O
Soviet	O
Union	O
at	O
the	O
Moscow	O
State	O
University	O
by	O
Nikolay	O
Brusentsov	O
,	O
and	O
it	O
had	O
notable	O
advantages	O
over	O
the	O
binary	O
computers	O
that	O
eventually	O
replaced	O
it	O
,	O
such	O
as	O
lower	O
electricity	O
consumption	O
and	O
lower	O
production	O
cost	O
.	O
</s>
<s>
In	O
1970	O
Brusentsov	O
built	O
an	O
enhanced	O
version	O
of	O
the	O
computer	O
,	O
which	O
he	O
called	O
Setun-70	O
.	O
</s>
<s>
In	O
the	O
United	O
States	O
,	O
the	O
ternary	O
computing	O
emulator	O
Ternac	B-Device
working	O
on	O
a	O
binary	O
machine	O
was	O
developed	O
in	O
1973	O
.	O
</s>
<s>
Ternary	O
computing	O
is	O
commonly	O
implemented	O
in	O
terms	O
of	O
balanced	B-Algorithm
ternary	I-Algorithm
,	O
which	O
uses	O
the	O
three	O
digits	O
−1	O
,	O
0	O
,	O
and	O
+1	O
.	O
</s>
<s>
The	O
negative	O
value	O
of	O
any	O
balanced	B-Algorithm
ternary	I-Algorithm
digit	O
can	O
be	O
obtained	O
by	O
replacing	O
every	O
+	O
with	O
a	O
−	O
and	O
vice	O
versa	O
.	O
</s>
<s>
Balanced	B-Algorithm
ternary	I-Algorithm
can	O
express	O
negative	O
values	O
as	O
easily	O
as	O
positive	O
ones	O
,	O
without	O
the	O
need	O
for	O
a	O
leading	O
negative	O
sign	O
as	O
with	O
unbalanced	O
numbers	O
.	O
</s>
<s>
This	O
research	O
theme	O
was	O
selected	O
as	O
one	O
of	O
the	O
future	O
projects	O
funded	O
by	O
Samsung	B-Application
in	O
2017	O
,	O
published	O
on	O
July	O
15	O
,	O
2019	O
.	O
</s>
<s>
However	O
,	O
Donald	O
Knuth	O
argues	O
that	O
they	O
will	O
be	O
brought	O
back	O
into	O
development	O
in	O
the	O
future	O
to	O
take	O
advantage	O
of	O
ternary	B-Language
logic	I-Language
's	O
elegance	O
and	O
efficiency	O
.	O
</s>
<s>
One	O
possible	O
way	O
this	O
could	O
happen	O
is	O
by	O
combining	O
an	O
optical	O
computer	O
with	O
the	O
ternary	B-Language
logic	I-Language
system	O
.	O
</s>
<s>
The	O
Josephson	O
junction	O
has	O
been	O
proposed	O
as	O
a	O
balanced	B-Algorithm
ternary	I-Algorithm
memory	O
cell	O
,	O
using	O
circulating	O
superconducting	O
currents	O
,	O
either	O
clockwise	O
,	O
counterclockwise	O
,	O
or	O
off	O
.	O
</s>
