<s>
Digital	B-General_Concept
physics	I-General_Concept
is	O
a	O
speculative	O
idea	O
that	O
the	O
universe	O
can	O
be	O
conceived	O
of	O
as	O
a	O
vast	O
,	O
digital	O
computation	O
device	O
,	O
or	O
as	O
the	O
output	O
of	O
a	O
deterministic	O
or	O
probabilistic	O
computer	B-Application
program	I-Application
.	O
</s>
<s>
The	O
term	O
digital	B-General_Concept
physics	I-General_Concept
was	O
coined	O
by	O
Edward	O
Fredkin	O
in	O
1978	O
,	O
who	O
later	O
came	O
to	O
prefer	O
the	O
term	O
digital	O
philosophy	O
.	O
</s>
<s>
Fredkin	O
encouraged	O
the	O
creation	O
of	O
a	O
digital	B-General_Concept
physics	I-General_Concept
group	O
at	O
what	O
was	O
then	O
MIT	O
's	O
Laboratory	O
for	O
Computer	O
Science	O
,	O
with	O
Tommaso	O
Toffoli	O
and	O
Norman	O
Margolus	O
as	O
primary	O
figures	O
.	O
</s>
<s>
Digital	B-General_Concept
physics	I-General_Concept
suggests	O
that	O
there	O
exists	O
,	O
at	O
least	O
in	O
principle	O
,	O
a	O
program	B-Application
for	O
a	O
universal	B-Architecture
computer	I-Architecture
that	O
computes	O
the	O
evolution	O
of	O
the	O
universe	O
.	O
</s>
<s>
Extant	O
models	O
of	O
digital	B-General_Concept
physics	I-General_Concept
are	O
incompatible	O
with	O
the	O
existence	O
of	O
several	O
continuous	O
characters	O
of	O
physical	O
symmetries	O
,	O
e.g.	O
,	O
rotational	O
symmetry	O
,	O
translational	O
symmetry	O
,	O
Lorentz	O
symmetry	O
,	O
and	O
the	O
Lie	O
group	O
gauge	O
invariance	O
of	O
Yang	O
–	O
Mills	O
theories	O
,	O
all	O
central	O
to	O
current	O
physical	O
theory	O
.	O
</s>
<s>
Moreover	O
,	O
extant	O
models	O
of	O
digital	B-General_Concept
physics	I-General_Concept
violate	O
various	O
well-established	O
features	O
of	O
quantum	O
physics	O
,	O
belonging	O
to	O
the	O
class	O
of	O
theories	O
with	O
local	O
hidden	O
variables	O
that	O
have	O
so	O
far	O
been	O
ruled	O
out	O
experimentally	O
using	O
Bell	O
's	O
theorem	O
.	O
</s>
