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R. Barrett and P. P. Delsanto
phases of both a photon and its entangled twin to be recorded simultaneously,
thus displaying in a most convincing way the reality of the entanglement.
Second, QE, far from being merely an intellectual curiosity, or even a
fundamental theoretical step towards our understanding of the mysteries
of nature, may also provide us with an ideal tool for the transition to the
quantum world, to which we increasingly appear to belong. Even though
at present it may seem farfetched, it seems likely that almost all branches
of science will eventually need to include quantum effects for particular
applications.
As an example, let us consider chemistry, a field that traditionally was
considered something of an “art”, rather than a science, although, of course,
its methodology is fully scientific. QM, with its strict mathematical basis, has
changed all that. When it was first formulated, and for a few decades thereafter, the pinnacle of glory of QM was the quantitative explanation of the
hydrogen atom as a composite of two particles: a proton and an electron.
Nowadays, QM is applied to complex atoms and molecules, using the most
refined computer techniques. Indeed, Quantum Chemistry has become one
of the most heavily mathematised of all the sciences.
Let us now turn our attention to biology and related sciences. Just a few
decades ago, nobody could have anticipated (except perhaps visionaries like
Schrödinger [8]) that a new science, Quantum Biology, would become a
major field of research. Although still in its infancy, Quantum Biology claims
to be able to explain hitherto unexplained puzzles, such as the amazing navigational skills of migratory birds in their transcontinental flights [9], or the
extraordinary efficiency of the photosynthesis process [10].
Based on quantum entanglement and on the superposition principle, i.e.
on the idea that, as we saw in Chap. 5, a quantum system is in all of its
possible states at the same time, until it is measured, Quantum Biology offers
explanations that appear more convincing than their classical counterparts.
However, there are still many open questions, as one might expect for a topic
that is the subject of active research.
In spite of the extraordinary relevance of Quantum Biology, the most
intriguing and sought after application of Quantum Entanglement (and of
the Superposition Principle) is Quantum Computing (QC), to which we
devote the remainder of this Section. It is interesting that the concept of a
wave function associated with each particle, which for physicists has been
one of the most difficult puzzles and headaches for decades, has now become
a blessing in disguise, from the point of view of QC. In fact, a classical
particle can carry very little information, i.e. its space-time coordinates and
R. Barrett and P. P. Delsanto
phases of both a photon and its entangled twin to be recorded simultaneously,
thus displaying in a most convincing way the reality of the entanglement.
Second, QE, far from being merely an intellectual curiosity, or even a
fundamental theoretical step towards our understanding of the mysteries
of nature, may also provide us with an ideal tool for the transition to the
quantum world, to which we increasingly appear to belong. Even though
at present it may seem farfetched, it seems likely that almost all branches
of science will eventually need to include quantum effects for particular
applications.
As an example, let us consider chemistry, a field that traditionally was
considered something of an “art”, rather than a science, although, of course,
its methodology is fully scientific. QM, with its strict mathematical basis, has
changed all that. When it was first formulated, and for a few decades thereafter, the pinnacle of glory of QM was the quantitative explanation of the
hydrogen atom as a composite of two particles: a proton and an electron.
Nowadays, QM is applied to complex atoms and molecules, using the most
refined computer techniques. Indeed, Quantum Chemistry has become one
of the most heavily mathematised of all the sciences.
Let us now turn our attention to biology and related sciences. Just a few
decades ago, nobody could have anticipated (except perhaps visionaries like
Schrödinger [8]) that a new science, Quantum Biology, would become a
major field of research. Although still in its infancy, Quantum Biology claims
to be able to explain hitherto unexplained puzzles, such as the amazing navigational skills of migratory birds in their transcontinental flights [9], or the
extraordinary efficiency of the photosynthesis process [10].
Based on quantum entanglement and on the superposition principle, i.e.
on the idea that, as we saw in Chap. 5, a quantum system is in all of its
possible states at the same time, until it is measured, Quantum Biology offers
explanations that appear more convincing than their classical counterparts.
However, there are still many open questions, as one might expect for a topic
that is the subject of active research.
In spite of the extraordinary relevance of Quantum Biology, the most
intriguing and sought after application of Quantum Entanglement (and of
the Superposition Principle) is Quantum Computing (QC), to which we
devote the remainder of this Section. It is interesting that the concept of a
wave function associated with each particle, which for physicists has been
one of the most difficult puzzles and headaches for decades, has now become
a blessing in disguise, from the point of view of QC. In fact, a classical
particle can carry very little information, i.e. its space-time coordinates and