The rhythms of Light and The Visualization of time
The Time Dimension of Space
Architecture is history written in stone. The history of architecture reflects the development and progress of human civilization. In his novel THE HUNCHBACK OF NOTRE DAME, the French writer Victor Marie Hugo (1865) states, “From the beginning of the world to the 15th Century, architecture has been the human’s magnum opus.” In other words, it is the highest example of human achievement. The historical aspect of architecture is self-evident. It recognizes the history inherent in a site and adapts accordingly. The Austrian philosopher and social reformer Rudolf Steiner (1998) maintained, “No matter we choose to admit or ignore the history of a site, it exists anyway.” And lastly, Steven Holl (1991) in his early work, ANCHORING, points out that buildings are inextricably linked to the site’s history.
Different architectural styles are reflections of the social and cultural history of different periods, reflecting the development and changes of the times. Therefore, architecture is not only the art of space, but also the art of time.
The definition of the universe in ancient China is the synthesis of time and space: they are inseparable concepts. Traditional Chinese architects maintain that architecture must show the integration of four elements: form, function, space and time (Shen Fuxi, 1989). Thinking of architecture from the perspective of time and exploring the essence of time from the perspective of space can together be seen as a time view of architecture (Giedion, S., 1967).
In 1905 and 1915, Albert Einstein’s theories of special and general relativity made a huge impact on man’s concept of space. According to Einstein, time and space are combined, so that space no longer exists in an objective dimension. The relationship between time and space can be found in ordinary three-dimensional space. This provides theoretical evidence for the time dimension of architectural space.
How Light May Be Used to Visualize Time in Space
Time can be directly mapped by the use of light, the most fundamental energy of the universe. The effect of light and shadow has a decisive effect in the shaping of buildings and space. It has been used to express the dimension of time since the beginning of human civilization, the standing stones of Carnac in Brittany and Stonehenge being but two examples. Light is widely used in religious architecture to express the concept of time. The following example illustrates the function of light in visualizing time in space.
Man’s need for religious worship, coupled with his yearning for light, can be evidenced in examples of early religious architecture. According to the Christian Bible, God’s first act was to create light and so, the Kingdom of God is the Kingdom of Light （ Von Campenhausen, H., 1977 ）. Hence, we may see that light may represent a state of grace, blessing and salvation in Christian doctrine.
The architectural history of Europe is closely linked with its religious history and to the former ’ s development through the ages. According to the 18th Century German philosopher Georg Friedrich Wilhelm Hegel （1998）, the most sublime examples of art are directly linked to religion and this can be seen in the religious architecture through the ages. As religion has developed, so too has religious architecture, with its constantly changing forms, from the original Roman Basilica, through Medieval Gothic and 18th Century Renaissance styles up to the modernism of the present day. However, though styles have differed, the basic religious requirements have not. Religious architecture aims to create a space where one may enter into a dialogue with God. Examples can be found in medieval Gothic churches such as Amiens and Salisbury Cathedrals, but also in classic contemporary religious buildings, Corbusier’s Ronchamp chapel and Tadao Ando’s Church of the Light being two examples. A religious space is created to enable dialogue between God and man and as such requires a very particular ambience. Louis Kahn has asserted that light is the language of dialogue between human beings and God （Büttiker, U. and Kahn, L.I., 1994）.
The Pantheon in Rome is the finest example of a circular building dating from ancient times. At its centre is a huge 30ft opening or oculus to the sky, the only light source in the entire building. The true function of this opening, however, remains uncertain. According to the Italian Astrophysicist Giulio Magli（2015）, “the sun and time were both linked architecturally in the ancient Roman period and they were used as a form of cosmological signpost for them.” During the dark winter months only the vaulted dome is illuminated, though at noon on both equinoxes light reaches the floor and on the 21st of April, the entrance at midday is brightly lit. Historian Hannah, R.（2015） have come up with an intriguing explanation for this: they suggest that the Pantheon was built as a giant sundial which would illuminate the Emperor entering the building on special occasions in the calendar. The intensity of the light at a specific time would thereby create an association between the sun and the power of Rome and thus would reinforce the Emperor’s divine right to rule. At such a time, the light creates a bright circle in the dome, contrasting sharply with the surrounding dark and so promoting a more fervent response in the worshipper.
So in conclusion, one may see that in addition to providing light to aid vision, the light in the Pantheon has two other functions: to create an ambience where a man may enter into a dialogue with God but also as a timekeeper, with the building itself acting as a huge sundial.
2. Absolute time and relative time
The time dimension of space: architecture provides multiple interpretations in its index of time. The architect Steven Holl（2011） has applied the “experience, relative and poetic”, many times in his architectural creations. In his latest book “Color Light Time”（2011）, he discusses the seven varieties of time in space: diurnal, seasonal, linear/cyclical, local site/global, duration of conception/construction, experiential and duration. These times are interwoven, but in concrete architectural practice two varieties are of greatest significance, namely, cosmic time and philosophical time, otherwise known as absolute time and relative time.
Absolute time (cosmic time)
Absolute time is a relatively objective method of timing, as in for example 365 days equaling one year, or one day consisting of 24 hours. Absolute time can be seen in buildings by the changing nature and position of the light. The experience of people in the building space is accompanied by changes in the light of different seasons at different times of the day, even though the changes are very subtle (Holl, S., 2011). In Steven Holl’s book, PARALLAX (2000), he proposes the concept of “light score” and “speed of shadow” and points out that “light travels over time, grows shorter and dissipates in the distance, thus forming an expressive architectural image.” In a building light can present itself in multiple ways and correspondingly, time in space shows itself as the integration of differing times of the day with differing seasons of the year.
“Sunrise accompanied by fresh vital light; high noon brings extreme searing light, diffuse and subdued colours of light appears at sunset. These are architectural daily celebrations, and spring, summer, autumn and winter are also being introduced to fill the building with different light from different seasons.” (Holl, S., 2011)
Relative Time (philosophy time)
From the ancient sundial, obelisk and sandglass to today’s cesium and rubidium atomic clocks, human beings continue to inspect and expand the measurement of time. However, we have come to realise that time seems to be an insoluble logical paradox, beginning with the thoughts on time by Aristotle and Augustine.
Aristotle defines time as a kind of ‘number of change’ with respect to the time before and the time after (Dover, K.J., 1994). He argues that time therefore is a kind of order and that it is objective, that is, not dependent on the mind or consciousness of man (Coope, U., 2005). Augustine offers a different philosophical view of time. He (1776) defines time as three kinds of present: present of things past, present of things present and present of things future, which correspond to memory, direct feelings and expectations respectively. Because memory, feelings and expectations exist in the mind, so time is closely related with human consciousness (Arnheim, R., 1969).
These two concepts of time, respectively derived from objective and subjective consciousness, have been fused in the theory of the French philosopher, Henri Bergson. Bergson, H. (1965) describes time as “duration” and points out that on the one hand, time is mastered through the mind and on the other, time can be quantified. In other words, time is not akin to pure empiricism where it exists in the chronological order of past, present and future; rather it manifests itself in completely different time periods, or different levels of time (Bergson, H., 1965). This concept of time, based on the interaction of the subjective and objective, is similar to the time view of Steven Holl, namely, the interaction of absolute or cosmic time with relative or philosophical time.
Steven Holl (2000) presents the complementary approach of absolute and relative time in the expansion project of the Nelson-Atkins Art Museum in Kansas City, presenting it as a focus of creation. The original museum was built in 1993 in the neo-classical style involving directional streamlines with focus on the interior. In contrast, the new museum expansion design integrates itself fully in the site, using an open streamlined design to lead the visitor’s eye towards the surrounding landscape and inviting us to enjoy a more flexible experience of time and space through the inclusion of multiple paths and entrances. One’s time here is not dictated; we are guided through the space in such a way as to feel that we are the time (Holl, S., 2011). This is a typical case of using relative time in architecture design.
3. The experiments of light and water
For the purposes of this project, let us explore the relationship between light and water. The first step is to test the effect light has on different materials to see which are best suited to express the concept of time.
Light is a form of electromagnetic radiation and is mostly invisible to the human eye. The wavelength of light that we can see is between roughly 380 and 760nm: only a small part of electromagnetic radiation. The American architect Louis Kahn (1994) states that “the sun never understood how great it was until it hit the side of a house.” The characteristics of light are dependent upon the positioning of the face and the surface material, presenting dynamic multi-dimensional fluid properties in both color and shape. So we have used solids, liquids and film to test a material’s characteristics and the spatial relationship between light and interface. The diagram below is a summary of our test content.
Combined with experiments and specific case analysis, we will compare the physical characteristics and psychological characteristics of water with the concept of time described above. And try to combine the temporal changes of the luminous efficiency of water to explain the temporal dimension of space.
3.1 The physical characteristics of water
Water is a liquid and so has no fixed form. Obeying the laws of gravity, it flows downwards. Therefore, the shape of water is defined by its container. It is both colourless and without taste. However, although colourless, it can reflect and so act as a mirror, portraying the contents and colours of its surrounding environment. In this way, it marries the real with the unreal and enriches one’s visual appreciation. The sound of water flowing can enrich one’s sensory perception, with the varying sounds creating different atmospheres: the soothing sound of a gentle stream is relaxing, the sound of waves crashing against the shore is invigorating and the constant clashing of a fountain can evoke strong emotions.
By experimenting with water, we can see that it is a highly adaptable medium, eminently capable of transformation. Its ever-changing nature lends itself to ever changing patterns of light and can as such reflect the state of absolute and relative time in space.
3.2 The psychological characteristics of water
As time can be seen as the interaction of subjective and objective consciousness, we must when analyzing materials in experiments, consider them from a psychological perspective.
The abstract nature of time requires us to readjust and reinterpret visually received information. Information-processing cognitive psychology emerged in the 1950s, inspired by the rise of artificial intelligence. The main objective in this branch of psychology is to determine human characteristics in information processing. Similarities can be seen between humans and computers: they both receive information (input), process it, create memory and react to it (output). However, psychologists in this field believe that humans search for and use information in an active and positive manner (Hicks, R.E., Miller, G.W. and Kinsbourne, M., 1976).
Visual perception is not just an objective visual record, since the human brain interprets what it perceives. The American architect William MC Lam states in his book, PERCEPTION AND LIGHTING AS FORMGIVERS FOR ARCHITECTURE (1977), “Seeing is not a passive response to patterns of light; rather, it is an active information-seeking process directed and interpreted by the brain. Visual sensory data are coordinated with incoming contextual information from the other senses related to past experiences of a comparable nature, and given attention or not depending on whether the incoming stimulus is classified as signal or noise.” With this in mind, we should consider how a material has been used through the ages in order to express the concept of time.
“An intention can be converted into a metaphor once, but if it is repeated as a representation and reproduction constantly, it will become a symbol or a part of symbol.” (Wellek, R. and Warren, A., 1956) It is clear that the “water” intention has been transcended to the simple meaning of nature, and its specific connotation is enshrined in the human consciousness construct. Thus we may see that water has come to symbolize nature. Cultural historian Feng think that when people tracking the source of various social sciences, they should go back to the myth this piece of holy land. We should therefore return to ancient mythologies that reflect early consciousness and psychology in order to trace the original perceptions of water. In doing so we can see that water in ancient times symbolized life, as personified in the mythologies of aquatic creation.
In the mythologies of aquatic creation, human ancestors used an “unconscious art form” to describe their belief that the world and with it, human beings, originated in water. An example can be seen in an ancient Indian myth: in the beginning, there was only water in the world; the water then gave birth to a golden egg from which hatched a sheep and the sheep became a human (Kosambi, D.D., 1965). These myths show how we now see water as a symbol of the meaning of life. In a sense, it could be argued that time is also a symbol of life, in its depiction of the passage of one’s life, with one’s death acting as a metaphor for the end of time.
Water flows and so too, it could be argued, does time: they are both linear and irreversible. According to the Greek scholar Heraclitus, “You can not step twice into the same river, for other waters are ever flowing on to you.” (Reichenbach, H., 1991) The analogy of time and water also appears in Chinese historical literature. Confucius, the ancient Chinese teacher and philosopher, says that, “the passage of time is just like the flow of water, which goes on day and night.” (Liu, W.C., 1972) So in conclusion, we may see that water as the symbol of life corresponds with time, and thus water is inextricably linked with time in the human consciousness.
4. Rhythms of light and time
After investigating the use of water as the medium connecting light and the time dimension of space, we explored the use of light to represent time from three aspects, namely, elements, techniques and effects.
4.1 The elements of shape
One of the experiments we undertook focused on the shape of light’s projection through the medium of water. We poured water into a suspended container and then proceeded to direct a current of air at it. As the airflow increased, so the water edges became more and more indistinct. The plane shape of the light effect can be divided into three types: point, line and face.
Point: The use of point-like light (or spotlight) is principally to focus one’s spatial visual awareness with the result being a feeling of gathering in a venue. Point is static, concentrated and directionless. When the point is in the centre of a space it lends a sense of stability, whereas if the point is directed off-centre, it will produce momentum. The space established by a body of water which has point light directed on it can form a visual focus to attract one’s attention, producing a sense of concentrated space.
Line: Line possesses the qualities of extension and direction in space. Linear light can lead one’s eye towards the distance and guide one’s path. In another set of experiments, we used the method of toggle and sonic vibration to obtain linear projections of different shapes of waves using water, the linear projection of flowing water being more directional than static water. Water ebbs and flows in the space, thereby increasing the depth and artistic conception of the space.
The following is an example of an art installation applying the use of linear light. This is a dark warehouse presented in Moscow. This large-scale art installation is 260 laser beams waxes and wanes to an ominous soundscape. The choreographed laser show frames disparate patterns and movements within its dark gridded platform, which looks more or less like an actual space ship (Nathaniel Ainley, 2016). The device uses the linearity of the laser to visually extend the depth of the space.
Face: A large area of light creates an open field visually. It is usually the case that the face form of light forms the background, highlighting the main focus in its use of contrast. In this case, the contrast between a large, bright background with the dark shadow makes the latter the main subject of the image.
The contrast between light and shade is a relatively common theme in contemporary architectural design. Shadows in contemporary structures are the products of rational analysis and expression. To cite two examples, Aldo Rossi designed a tall colonnade in his Gallaratese housing complex to create strong shadows and likewise in his ossuary cube in the Cemetery of San Cataldo with its regimental openings puncturing the walls (Rossi, A., Ratcliff, C. and Lew, S., 1993.) These strong shadows in both works produce an atmosphere which encourages contemplation in the onlooker.
The way A. Rossi uses shadow in his design is similar to the metaphysical paintings of Giorgio de Chirico during the years 1912 to 1918. “Giorgio de Chirico concerns himself with the forbidding nature of how time and space can be architecturally represented. In his paintings time becomes an abstraction, where the future is implicit but not specific. Light and shadow evoke not only an aesthetic response in the viewer, but also a psychological and spiritual reaction.”
Light and shadow as a psychological and cognitive phenomenon plays a significant role in psychological development. “On the one hand, light seems to always be associated with consciousness and vision; on the other hand, shadow is always linked with the subconscious and the deep structure of the unconscious.”
It is often difficult to examine light and shadow as an abstract concept; they are usually associated with specific memories and experiences. The Danish architectural historian Steen Eiler Rasmussen (1964) states in his book, EXPERIENCING ARCHITECTURE, that shadow is never black and meaningless; the shimmer and flicker of dark space will reflect the shadow. And the Finnish architect Juhani Pallasmaa (1999) opines in his COLLISION AND CONFLICT, “in the best architectural spaces there is always a sustained, deep and eternal marriage between light and shadow.”
4.2 Expressive Techniques
How we set a lighting effect is dependent on the unit: a light effect unit contains a light source, a medium and a projection surface. A single source of light in a space will always create a sense of being enclosed, especially when the light source and the space are not balanced. The one bright spot becomes the visual focus. A single light effect assumes a dominant position, with the surrounding environment being relatively simple. Where elements such as walls, doors and ceiling are placed can create a sense of confinement; putting the light effect in the centre of a space can give focus and give an illusion of greater space.Combining light sources: When there is more than one light source, the effect of light and shadow does not evoke the feeling of a simple enclosed space, these scattered light effects usually need to be organised in accordance with a certain sequence.
Repeat: Repeat refers to the employment of the same or similar forms continuously and regularly. The repetition of a theme in the composition contributes to the harmony of the building as a whole, and the unity of the building can be enhanced by repeated design techniques. The repetition of the direction, the repetition of the size, the repetition of the shape, the repetition of the texture, the repetition of the tones, etc., are commonly used in the design of the environment. Repetitive composition can enhance the rhythm of composition. Vocal repetition can enhance memory and the same may be said for visual repetition. Repeated use of the same or similar effects of light and shadow enhances the power of the light and so gives a sense of order (Nash, H. and Stroupe, S., 1999).
An example to illustrate this is MOMENTUM, an art installation in the Curve Gallery at the Barbican in London in 2014. Created by United Visual Artists to celebrate the Curve’s tenth anniversary, the installation combined light, sound and motion to create a fully immersive experience, responding to the unique space of the Curve. It consisted of twelve pendulums, each pendulum being meticulously designed and constructed from steel, aluminium and electronics. Twelve pendulums swung in the same time and same angle, which creates drawing attention to the Curve’s vast arc and inviting the audience to explore the space and experience a heightened sense of awareness and wonderment.
Contrast: The contrast between soft, ever changing light and the geometrically rigid features of a building can produce a strong visual and psychological response. Light is implicit and inclusive, a building is hard and solid; so we have the contrasts of soft and hard, virtual and real. The light can be variable but the physical space is constant; thus, though the physical size of a space remains unchanged, changing the lighting effects can create different atmospheres within that space.
4.3 Time effect
Art may be created using time in three dimensions: compression, amplification and stagnation.
Time compression and extension
In film, the compression of time is caused by downgrading, that is to say, the difference between the speed of the camera and the speed of the projector. If the movie projector is faster than the speed of the camera, the action on the screen will accelerate and conversely, if the movie projector is slower than the speed of the camera, the action on the screen will decelerate (Georgiev, T. and Wainer, M., 2001). Hence, the key point is comparison. It seems to be very necessary to find a reference which is relative to time and compare these two things to guide the time dimension of space.
The flash-lag effect uses light to interfere with one’s sense of time. It involves the visual illusion of flashing on the same position as a moving object (Nijhawan 1994, Whitney 2002). The classic flash-lag effect experiment is shown in Image14: on a screen, we see a ring following a circular path. After a period of time, the centre of the ring emits a short flash (see the white disc in Image14). The experiment results show that, even though the position of the flash and the and the moving object are the same, they are perceived to be apart. This flash-lag effect demonstrates the internal mechanism of human visual perception: we receive the information of the location of the moving and stationary objects, but transient visual stimulation lags behind sustained visual stimulation. There is an explanation for this flash-lag effect (or FLE): when light from a moving object hits our eye, the brain requires a certain amount of time before the object is perceived and so in reality the position of the moving object is the same as the position of the flash.
Time standing still
In film, time standing still is caused by a fixed frame within the lens. Freeze frame may be used as a special effect to enhance the narrative of the camera action and to lend special importance to a moment or character. Without the benefit of electronic equipment, how may we perceive this time of still or hiatus? Aristotle states that, “If our own consciousness has not changed at all, or has changed without our being aware of it, we will not think that time has passed.” (Coope, U., 2005)
So, realizing the contrast between movement and stasis leads to a recognition of time stagnation. When we move away from being self-obsessed and start to take in and appreciate our environment, it can feel as though time is standing still and we are alive to that moment. Through his use of light, the Japanese architect Tadao Ando manages to create a sense of time stagnation – or of time standing still – in his design of the Water Temple (Drew, P. and Andō, T., 1996). We enter into an ethereal world after walking through a pure white passage, an underground space lit by a faint blue light which gradually turns to an intense blackness: a symbolic death where life and time draw to a halt.
5. Design proposal
Through a series of experiments and case studies we have attempted to analyse the basic shape elements of lighting effects, artistic expressions of light’s rhythms and the different states of time dimension. How light can portray the dimension of time in space is both subjective and objective. Due to the variability of experimental conditions and of our different responses, together with the difficulty inherent in grasping and making sense of what we perceive, it is impossible to extrapolate a precise rule or conclusion. The following questions have been discussed above: What is the time dimension of space? How can light and shadow together represent time? Why is water as a material a successful medium for this project?
As well as answering these questions, we must try to summarize some common and relatively identifiable experiences in order to establish a set of rules that will facilitate the next stage of design. The installation pictured tries to address the question, how does the visualisation of time in space change according to the different rhythms created by the combination of water and light?
Using LED light, transparent containers and water we created a unit which we suspended from the ceiling. We then used a trigger servo robotics board to introduce a morphological change in the projection of the water. As with the previous experiment, we tested the ambience of time suggested by different states of water projection. We propose that the next stage should combine many units together to enrich the spatial and layering aspects and thus enrich the time dimension of space.
This design report has focused on investigating light and time in space. In the course of this investigation we have demonstrated what is meant by the time dimension of space and how light and shadow together may represent time. We have looked at why water as a material is a successful medium for the representation of time and how the visualization of time in space can change according to the different rhythms created by combinations of water and light.
We conclude that:
According to Einstein’s theories of special and general relativity, time and space are combined, so that space no longer exists in the objective dimension. In other words, there is a time dimension for space. This includes absolute or cosmic time and relative or philosophical time.
Light has been made use of since the beginning of human civilization: how it has been used gives us a direct map of time. Light is widely used as a metaphor to express the concept of time.
The physical characteristics of water make it highly adaptable and eminently capable of transformation. Like time, water has been used in a metaphysical sense to express the concept of time.
The combination of light and water can produce different rhythms by using the three light effects of point, line and face on water and then introducing elements such as an enclosed space, repetition and contrast, to design space that shows the dimension of time.
Additional research should focus on more detailed and rigorous experiments. Only by doing this can we make significant advances in the exploration of light and time in space. By continuing to study the dimension of time it is believed that we will be able to develop the potential that space can offer.
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