Interference
patterns, double-slit experiments and art?
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a project associated with FUFF
properties of
this
project
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- students
from different backgrounds join to form a dynamic group to study into
the subject
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goals: observing and gaining knowledge on interference patterns,
applying interference patterns in direct or as a
conceptual metaphor
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complementary properties of this projects (FUFF) contain:
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ifuz net, who has invited to this project in the frame of 95qm project
of Oguz Tatari (see below), is acting as a kind of transmitter/emitter
(complementary to a lecturer or professor, as the FUFF does
only know students). so ifuz net is giving impulses, not leading the
project
- the use of 'project' and 'group' avoids the term 'seminar ', which is
focussing on the similarity, while we are rather looking for
complimentary forms
- (list t.b.c.)
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Starting point
Interference patterns, examples:
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examples: interference patterns in
physics - waves
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(useful link: http://en.wikipedia.org/wiki/Interference)
the
most obvious form of waves we know is waves in water.
if we drop a stone into a pool of still water we will be able to
observe expanding circular waves around the specific location.
if we drop two stones simultanously at two differnt spots we will be
able to see two sets of expanding circular waves which sooner or later
will clash with each other.
they will 'interfere'.
this is similar to the animation below:
waves
and
interference can be described by mathematical functions, which to
understand is not necessarily important for our purpose, but which
exlplains the relation to the advanced physical phenomena from the
quantum world we will see later.
we find those waves in acoustics, too, as we know, and as a possible
property of light (again later)
so we have now already seen our first interference pattern here, a more
complicated pattern which resulted from the interference of two simple
patterns which each alone did not contain such complicated views.
a wave at a particular location can be described also as a function of
time like in the graph below
a second wave which interferes can be just added.
as we have positive values and negative values, waves can cancel each
other out in part or in whole, which is then called destructive
interference (happens if one wave has a positive value and the other
one has a negative value at the same time).
there will occur constructive interference as well, if both waves have
positive values at the same time or have negative values at the same
time, the will amplify each other.
(for us, as we are interested in the creation of new patterns, both
variations can be viewed as being constructive of course)
cases of alternating constructive and destructive interference can
include the special case of a 'schwebung', which is a wave with a
longer
amplitude 'surfing' on a wave with a short amplitude. it can be
produced by adding two regular wives with slightly different amplitudes
(frequencies).
'schwebung' is the german word for it, in english it seems to be
referred to as 'beat' (http://en.wikipedia.org/wiki/Beat_(acoustics))
this has
been our second example where a more compex pattern can result from the
interference of two more simple patterns.
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examples:
moiré-patterns in physics - waves
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(useful link: http://en.wikipedia.org/wiki/Interference_pattern)
many of us know moiré
patterns from digital photography (or television)
we can show the effect with two simple patterns of parallel lines layed
over each other.
the pattern in pink covered is similar to the black one through which
we view it, it consists of simple parallel lines.
actually two interferences happen here:
many of us will see alternating pink and white horizontal stripes.
this is an interference by our cognition system, our brains are
interpreting what we see and trying to match it to patterns we already
know, which are moste likely, common, recent, or emotionally connected.
so our brain is suggesting there might be pink and white horizontal
stripes underlying a covering grid of black stripes.
but there is an objective interference:
what can be seen by covering the pink grid with a black grid are sets
of alternating small pink and white parallelograms in the spaces
between the black bars.
moiré patterns can easily become complicated as the simple
overly of two circle patterns suggests:
adding to the interference of the circles and the interpretation by our
cognitive system, is the interference of the screen mask, which makes
it
difficult to display one circle pattern alone without moiré
effects.
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examples: interference
by cognition
examples:
interference
patterns in linguistics
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(medium useful link: http://en.wikipedia.org/wiki/Language_transfer)
the most obvious interference
pattern in linguistic is when a native speaker of language1 speaks or
bettern learns language2 when language2 has a (slightly) different
structure.
immediately apparent is the phonological interference as two languages
usually have differnt sets of distinguishing phonems, different
melodies etc..
it can be realised more obvious when f.e. having a Japanese trying to
speak English as a learner.
he has learned and hears in system mostly consisting of units of
connected consonant and vocal. so he or she hears, tries to understand
and to reproduce English 'viewing' through this interfering pattern.
so 'France' becomes 'Fu-Ra-N-Su'.
there is also syntactical interference and semantical/metaphoriacal
interference.
(it might be one reason why Dutch coaches are so admired in German
football, because their expression suggest new views, although actually
their analysis might not be that more versatile.)
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Interference
patterns from the quantum world:
wave particle duality and the double-slit-experiment:
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the double-slit experiment
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(useful link: http://en.wikipedia.org/wiki/Interference_pattern)
a very entertaining comic video to
introduce here is this Dr. Quantum clip:
http://youtube.com/watch?v=DfPeprQ7oGc
the
original double-slit experiment was made in the
beginning of the 19th century to prove that light consists of
waves.
Thomas Young sent light through
two parallel vertical slits onto a projection screen behind the screen
with the slits.
What should be expected on the projection screen is of course two
parallel vertical bands of light.
Instead the baffling result is an alternating pattern of vertical
bright and dark bands of light, looking exactly as if two waves
had been sent from the slits and interfering with each other like water
waves.
strangewise later experiments by other scientists seemed to prove
anyway that light consists of particles.
what was an impossible
contradiction eventually was explained as indeed
possible by the theories of quantum mechanics in the first half of 20th
century.
this java applet demonstrates the experiment quite well:
http://vsg.quasihome.com/interfer.htm
it can be seen here why it is difficult to
reproduce
the experiment in a satisfactory manor with daylight or normal lamps.
the actual variation of the interference pattern depends on tzhe
wavelength of the light. white light is a mixture of light of all
colors (light with different wavelengths). so with normal light we get
different interference patterns blurring each other out. too much
interference sotosay...
In the 20th century the
double-slit experiment has been reproduced with
electrons and similar experiments meanwhile have been successful even
with atoms and a particular molecule.
While sending the particles through one slit results in a behaviour
that is expected from particles of matter, sending them through two
slits ends in a result which can be described exactly by mathematical
functions describing waves. This phenomena is referred to as
'wave-particle duality'.
another exciting phenomena is the 'collapse of the wave function'. if a
measuring device is installed at one of the slits, the electrons return
to a result expected from a behaviour as matter: the wave function
collapses and instead of the interference pattern indeed two simple
bands are seen on the projection screen.
the
'interpretations' underlying in the dr.quantium clip linked to above
are solely owed to the entertainment desire of the author(s), they are
not based on scientific knowledge. electrons very unlikely 'feel
watched' and change behaviour because of that.
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starting
to experiment with: the application of interference patterns idea,
direct or metaphorical:
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examples: interference patterns by
a printer
examples: interference by a print medium
examples: interference
by an abstract pattern with meaning
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(vive la dictature example, will follow)
(marcuse ad example, will follow)
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first
steps of the group:
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reflection / analysis or
experimental application
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the initial meeting took place in
the frame of Oguz Tataris
95qm project at the Atelier Frankfurt with 8 students from the local
area. it has been the decisive eventual impulse to actually realize
this project, and a big help in the moment other places (esp. the e57)
were inaccessible because of the room situation.
the students of the first meeting seem more interested in the
experimental application of the concepts, especially as a conceptual
metaphor. for this the first step concluded has been to consider a
subject for experiments with interference patterns from the individual
perspective.
we will then form individual correspondence and dialogue units in ways
which appear the most productive, and probably meet from time to time
as a group, too..
any ways of communication will be useful: internet, phone and locally,
meetings in the Experimental Bureau e57, or other places if the
individuals decide so. a fixpoint may be sundays at 5 pm at the e57.
the
group is still very open to join for more students (as usually not all
students of the first meeting will be able to continue with the
project).
yet the project had been advertised only locally but it is not
restricted to location.
depending
on the background and interest of the individual, students can also go
into the direction of research of deeper knowledge into the suggested
fields in which the concept interference patterns already exist,
outspoken or unconcious.
this maybe in physics, in language, in music or acoustics in general,
or in domains not mentioned here.
(from linguistiucs it might be an exciting
impulse to try to distinguish syntax patterns form semantic patterns in
other domains, too)
it maybe in art we can detect and collect examples of alreadyexisting
applied interference patterns.
which leaves enough room for students with backgrounds in various
domains.
or rather in any domain as other directions can be derived from the
backgrounds and interests of any students who might additionally join
the group.
the results of the reflecting students then can be confronted with the
experimental ideas of the experimenting students and make the process
more dynamic.
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results of the group:
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results
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first we gathered knowledge on classic interference patters and the concept itself.
in the next step we thought about more abstract levels of interference patterns.
in both we experimented with producing new interference patterns. among otherws. we xeperimented with printers .
there is a book with results that can be visited in the exhibition space of the Experimental Bureau e57 www.e57.org
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