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The Physics of Chanukah: On the
Nature of Light
We need to listen to the story that the Chanukah lichtelech
(flames) tell us
– The Rebbe Yosef Yitzchak Schneersohn
A little light dispels a lot of darkness
- The Sages
Light is the core of physics. Light – energy –
defines the very parameters of existence.
In modern physics it is now commonly accepted
that light, or in more general terms, electromagnetic radiation
(microwaves, radio waves, light rays, x rays, gamma rays) has
a dual nature: it behaves both like a wave and a particle. The
same has been proven regarding the behavior of subatomic matter:
it appears as both a particle and a wave.
And this is no small matter: A particle and a
wave are opposites. A particle is an entity confined to a very
small volume, while a wave is spread out over a large region
of space.[1] How light can be both a wave (a
field of energy) and a particle (a discrete entity) remains
one of the biggest mysteries in science, yet it has been proven
time and again despite its inherent paradox.
A fascinating fact: Long before science discovered
the importance of light, the Kabbalah uses light (ohr)
as the ultimate metaphor to describe G-d’s ‘expression,’ i.e.
the Divine transmission – the energy that brings existence into
being and makes up all of existence. Light reflects, expresses
and transmits the Divine energy. Existence is ‘light’ emitted
from the Divine.
And like physics would later discover, Jewish
mysticism (as explained at length in Chassidic thought, see
for example, the discourse Vayeilech 5666 from the Rebbe Sholom
DovBer) describes the dual nature of light. Light combines both
substance and no substance: it has no substance of its own;
it always reflects its (luminary) source. Yet, precisely because
of its transparent bittul (selflessness), light purely
reflects and channels the deepest ‘substance’ of the source,
with no ‘personality’ of its own to get in the way.
Light, with all its paradoxical qualities, is
our best metaphor for understanding the process of creation.
By contemplating the paradox of light -- that it is clearly
real and yet appears to have no substance or shape -- we can
approach an even greater paradox: the unity of our physical
universe with the ‘universe’ of G-d. The mysterious qualities
of light illustrate the main truth of our physical universe:
that an existence must not be defined only in terms of its own
being, but as a means to illuminate a higher truth. Light becomes
both a pure expression of the Divine and the metaphor that,
through our reason and other faculties, allows us to experience
the ways of G-d.
Light straddles the defining line that runs between
the physical and the spiritual. Light – sans weight, sans mass,
sans just about any of matter's properties – is the most ethereal
of physical “things.”' Perceptibly real, yet free of the qualities
we ascribe to the objects of our perceptible universe, light
serves as a bridge of allegory between a mind grounded in a
material environment and the metaphysical abstractions it contemplates.
Light, in other words has a dual quality of both
particle and wave. It is a defined entity of its own with its
own distinct ‘space,’ yet its ‘particle’ identity’ is wave-like,
spread out like an energy field, carrying Divine energy into
existence, like ocean waves washing up on the shore.
Chanukah is the Festival of Light. All the events
of Chanukah are remembered and celebrated with light. We kindle
the Chanukah flames to commemorate the victory of the ‘few over
the many,’ the ‘weak over the mighty’ and the miracle of discovering
the small crucible of olive oil which then burned for eight
days. The Temple was subsequently rededicated (hence the name
Chanukah which means ‘dedication’). All this is commemorated
with light.
Chanukah – like light – is paradoxical:
The essential miracle – and message – of Chanukah
is the dominance of light over dark, of spiritual radiance over
material gloom. Even in dark times, even when the mighty materialistic
Syrians/Greeks desecrated all things sacred, even as all sources
of pure light (from pure olive oil) were gone, ultimately one
crucible of purity remained, and revived the soul. The powerful
quality of light – even a minimal amount – prevailed over the
strongest forms of darkness.
And the light that emerges from darkness is the
strongest light of all. As the Ramban writes (beginning of Parshat
Behaalotcho), that ‘these [Chanukah] flames will never be extinguished’
(unlike the Temple Menorah which ceased shining after the Temple’s
destruction). Light that prevails after being challenged by
darkness is a light that can never die.
This, of course, is the root of all paradoxes:
It’s one thing to find light in good times. It’s a completely
other matter to find it in darkness. Chanukah is a time when
we face darkness, yet we emerge with even greater light.
Thus the Chanukah lights are kindled in a fashion
that reflects their inherent paradox – a paradox that integrates
“particle” and “wave”: The light of Chanukah permeates and fuses
both the ‘particle’ world – a very specific space and defined
state of being, reflecting the discreteness and diversity of
the material world, and the ‘wave’ world – a large field of
energy that unites the entire spectrum.
In space: We light the Chanukah flames “at the
door of the home facing outward.” It’s in your home and all
that a home implies, facing the outside and all that ‘outside’
implies.
In time: “From when the sun sets” – we light the
candles at night. Night represents darkness, and the lights
of Chanukah have to pierce and illuminate the shadows.
The actual lamp and lighting process itself entails
opposite forces uniting: A lamp consists of oil, a wick, and
a vessel containing them so that the oil is fed through the
wick to a burning flame. All these particles together create
a wave of light and warmth that is more than the sum of their
parts. The flame and the wick defy each other, while joining
forces and causing each other to act against their inherent
natures as they attach to each other: The flame licking ever
upward, only to be grounded by the material wick. The oil too
plays a conflicting role, as it both fuels the destruction of
the wick and yet ultimately sustains it. Were it not for the
oil, the wick would be immediately consumed by the flame; yet
at the same time, the oil is acclimating the wick to the flame,
in effect transforming the wick into fuel for the flame. The
oil actually requires the wick to channel its substance and
convert it into an illuminating flame. Fusion of oil (fuel)
and wick (and vessel) – wave and particle – create light.[2]
The colors of the flame also reflect a dual personality:
‘Nehura uchoma’ – the ‘dark radiance,’ burning close
to the wick, and ‘nehura chivra’ – the white flame farther
from the wick, the ‘bright radiance.’[3]
The nature of light is such that it unites: one
flame’s light merges with another – like one large wave. Yet
we light the Chanukah flames as individual ‘particles’ – each
flame must be lit separately (with sufficient space between
them so they do not become one), each night a new additional
flame.
“These [Chanukah] lights are sacred, and we are
not permitted to make use of them, but only to look at them,”
yet we benefit from them in many ways. Indeed, this message
itself (that these light are sacred) offers us the greatest
benefit of all: By not being permitted to make use of the lights,
only to look at them, we learn from them how to sublimate ourselves
and to become reflections of a Higher truth than ourselves,
rather than indulging our needs and doing things only for our
own benefit.
We refrain from work while the flames are burning.
Yet, the days of Chanukah are workdays. We gather with family
and friends, party, eat latkes, play dreidel – celebrate the
‘particles’ – while we always remain focused on the deeper spiritual
light waves radiating from Chanukah.
The quantum particle/wave paradox of light – which
defines the very essence of Chanukah – can help explain many
other unusual elements in Chanukah. For example:
The Talmud (Shabbat 22b) discusses the essence
of the mitzvah of Chanukah lighting. Is the primary mitzvah
the ‘kindling’ or the ‘placement’ of the menorah? Perhaps the
difference of these two approaches can be understood in context
of light’s paradoxical properties of particle and wave: Is the
primary focus of Chanukah light the location, the space – the
‘placement,’ the effect of the light on physical space (the
particle aspect), or is it the act of creating and drawing down
the light – the ‘kindling’? The conclusion is that the ‘kindling’
is the essence of the mitzvah; the wave aspect is dominant.[4]
The vessel too poses an interesting paradox. Our
Rabbis wonder whether the vessel itself is an actual part of
the mitzvah of the Chanukah candles, or does the mitzvah entail
just wick and oil (and the vessel is incidental). The question
is to what extent does the role of the vessel play in the Chanukah
lights. The ruling opinion is that the vessel is part of the
mitzvah. According to the other opinion, the mitzvah is the
flame that is lit in the vessel, not the vessel itself.[5] The vessel or container represents
the material world, which needs to be transformed into a container
and fuel for Divine light, until the vessel itself is revealed
to be an extension of the light. The issue at hand is to what
extent does the vessel become one with the light.[6] This too can be understood in context
of trying to determine what exactly is the relationship and
balance between the particle and wave aspects of light.
The list goes on. Chanukah can teach us much about
the nature of light, and light can illuminate many aspects of
Chanukah. Using this template as an invitation, perhaps scientists
and theologians, physicists and Torah scholars, psychologists
and soul doctors, can explore further parallels between
both these worlds, helping uncover the Unified Field Theory
that unites them (us) all.
What truly strikes me in all of this is the proactive
role Chanukah demands of us:
In physics, light is an existing entity that we
humans try to understand, we are amazed at its paradoxical qualities
and finally develop methods how to tap into it to better our
lives. In Torah, Chanukah teaches us how we can generate
light, how we can create unity within paradox. We are not simply
observers – ‘observant’ Jews – watching from the sidelines and
studying phenomenon around us; we actually initiate and create
the phenomena.
And perhaps, therein lies yet another – maybe
the most important – element in Quantum Chanukah: We are not
just mere observers. The observer actually affects the observee.
Our attitudes, our actions in fact change the course of this
world. When we light Chanukah candles we release new energy
into the world that shapes the future.
Think of that when you light the Chanukah flames.
Listen to their story; they have much to tell.
“These [Chanukah] lights are sacred, and we are
not permitted to make use of them, but only to look at them,
in order to offer thanks and praise to Your great Name, for
Your miracles, for Your wonders and for Your acts of salvation.”
[1] A wave is not just a bunch of particles moving in a wave pattern;
it is a distinct form of energy, as different from traveling
particles ‘as the notion of waves on a lake from that of a
school of fish swimming in the same direction’ (Victor Weisskopf,
Physics in the Twentieth Century – selected essays, p.
30).
[2] See Rabbi Dovber of Lubavitch, Shaarei Orah (Gates of
Radiance), Ki Atah Neiri. Just published in English
(Kehot, 2002).
[3] See Zohar I:51a. Shaarei Orah ibid.
[4] See Pri Etz Chaim, Shaar Chanukah. Cited
in Shaloh, mesechta Tomid.
[5] See Avnei Neizer, Orach Chaim, 500.
[6] See Likkutei Sichos vol. 5 p. 445-446.
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