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### What is teleportation? ** In the Classical world: ** In o...
![teleportation scheme](http://i.imgur.com/yUuNyuj.png?1 "Teleporta...
An **EPR pair** is a pair of particles that are entangled with each...
The **singlet state** is an entangled state of system of two or mor...
Before discussing the teleportation phenomenon let us first underst...
#### A simple example of teleportation: Consider two scientists Al...
It is interesting to notice that for the teleportation to be comple...
The teleportation procedure described above uses a system of 2 enta...
**Remarks about human teleportation:** A human person is composed ...
#### Experimental results about Quantum Teleportation: In Octobe...
VOLUME
70
29
MARCH
l993
NUMBER
13
Teleporting
an
Unknown
Quantum
State
via
Dual
Classical
and
Einstein-Podolsky-Rosen
Channels
Charles
H.
Bennett,
~
)
Gilles
Brassard,
(
)
Claude
Crepeau,
(
)
(
)
Richard
Jozsa,
(
)
Asher
Peres,
~4)
and
William
K.
Wootters(
)
'
IBM
Research
Division,
T.
J.
watson
Research
Center,
Yorktomn
Heights,
¹m
York
10598
(
lDepartement
IIto,
Universite
de
Montreal,
C.
P
OI28,
Su.
ccursale
"A",
Montreal,
Quebec,
Canada
HBC
817
(
lLaboratoire
d'Informatique
de
1'Ecole
Normale
Superieure,
g5
rue
d'Ulm,
7M80
Paris
CEDEX
05,
France~
i
l
lDepartment
of
Physics,
Technion
Israel
In—
stitute
of
Technology,
MOOO
Haifa,
Israel
l
lDepartment
of
Physics,
Williams
College,
Williamstoivn,
Massachusetts
OIP67
(Received
2
December
1992)
An
unknown
quantum
state
]P)
can
be
disassembled
into,
then
later
reconstructed
from,
purely
classical
information
and
purely
nonclassical
Einstein-Podolsky-Rosen
(EPR)
correlations.
To
do
so
the
sender,
"Alice,
"
and
the
receiver,
"Bob,
"
must
prearrange
the
sharing
of
an
EPR-correlated
pair
of
particles.
Alice
makes
a
joint
measurement
on
her
EPR
particle
and
the
unknown
quantum
system,
and
sends
Bob
the
classical
result
of
this
measurement.
Knowing
this,
Bob
can
convert
the
state
of
his
EPR
particle
into
an
exact
replica
of
the
unknown
state
]P)
which
Alice
destroyed.
PACS
numbers:
03.
65.
Bz,
42.
50.
Dv,
89.
70.
+c
The
existence
of
long
range
correlations
between
Einstein-Podolsky-Rosen
(EP
R)
[1]
pairs
of
particles
raises
the
question
of
their
use
for
information
transfer.
Einstein
himself
used
the
word
"telepathically"
in
this
contempt
[2].
It
is
known
that
instantaneous
information
transfer
is
definitely
impossible
[3].
Here,
we
show
that
EPR
correlations
can
nevertheless
assist
in
the
"telepor-
tation"
of
an
intact
quantum
state
from
one
place
to
another,
by
a
sender
who
knows
neither
the
state
to
be
teleported
nor
the
location
of
the
intended
receiver.
Suppose
one
observer,
whom
we
shall
call
"Alice,
"
has
been
given
a
quantum
system
such
as
a
photon
or
spin-&
particle,
prepared
in
a
state
]P)
unknown
to
her,
and
she
wishes
to
communicate
to
another
observer,
"Bob,
"
suf-
ficient
information
about
the
quantum
system
for
him
to
make
an
accurate
copy
of
it.
Knowing
the
state
vector
]P)
itself
would
be
sufficient
information,
but
in
general
there
is
no
way
to
learn
it.
Only
if
Alice
knows
before-
hand
that
~qb)
belongs
to
a
given
orthonormal
set
can
she
make
a
measurement
whose
result
will
allow
her
to
make
an
accurate
copy
of
[P).
Conversely,
if
the
possibilities
for
~P)
include
two
or
more
nonorthogonal
states,
then
no
measurement
will
yield
sufhcient
information
to
prepare
a
perfectly
accurate
copy.
A
trivial
way
for
Alice
to
provide
Bob
with
all
the
in-
formation
in
[P)
would
be
to
send
the
particle
itself.
If
she
wants
to
avoid
transferring
the
original
particle,
she
can
make
it.
interact
unitarily
with
another
system,
or
"an-
cilla,
"
initially
in
a
known
state
~ap),
in
such
a
way
that
after
the
interaction
the
original
particle
is
left
in
a
stan-
dard
state
~Pp)
and
the
ancilla
is
in
an
unknown
state
]a)
containing
complete
information
about
~P).
If
Al-
ice
now
sends
Bob
the
ancilla
(perhaps
technically
easier
than
sending
the
original
particle),
Bob
can
reverse
her
actions
to
prepare
a
replica
of
her
original
state
~P).
This
"spin-exchange
measurement"
[4]
illustrates
an
essential
feature
of
quantum
information:
it
can
be
swapped
from
one
system
to
another,
but
it
cannot
be
duplicated
or
"cloned"
[5].
In
this
regard
it
is
quite
unlike
classical
information,
which
can
be
duplicated
at
will.
The
most
tangible
manifestation
of
the
nonclassicality
of
quantum
information
is
the
violation
of
Bell
s
inequalities
[6)
ob-
served
[7]
in
experiments
on
EPR
states.
Other
rnanifes-
tations
include
the
possibility
of
quantum
cryptography
[8),
quantum
parallel
computation
[9],
and
the
superior-
ity
of
interactive
measurements
for
extracting
informa-
1993
The
American
Physical
Society
1895