Perception is fundamental to the advancement of science and technology. Perceptive ability is one of the great strengths of Caltech's people. PERCEPTION contains various allusions and illusions that can be perceived from different vantage points. The allusions reference scientific principles, science history, Caltech, the Global Environmental Science initiative, and the Linde + Robinson Laboratory, including its history and purpose (both original and current).
The upper part of the sculpture is constructed from 32 aluminum rods, referencing the 1932 original construction of Robinson Laboratory. The rods are arranged to form eight hexahedra, seven of which are contained within an outermost hexahedron. The outermost hexahedron is a rhombohedron that symbolizes Caltech. The seven inner hexahedra symbolize Caltech's six current academic divisions and its JPL division, all of which have important roles to play in the activities of the Ronald and Maxine Linde Center for Global Environmental Science that is housed in the Laboratory. Each edge of the outer rhombohedron is equal in length to one ten-millionth of the diameter of Earth along its axis of rotation.
The innermost hexahedron also is a rhombohedron. The two rhombohedra have a common orientation and common positioning of their respective longest axes. The relative sizes of the rhombohedra, diameters of the rods forming the rhombohedra, and taper of the connecting rods all exhibit the so-called Golden Ratio, also known as the Divine Proportion (based on the irrational mathematical constant phi = 1.61803...).
The rhombohedra are positioned so that a common point in space divides their respective longest axes into the Golden Ratio, constituting a "virtual nucleus" for the upper part of the sculpture. When viewed from different vantage points, the sculpture displays different geometric relationships that result from the shapes, positioning and open sides of the component polyhedra. These changing appearances of juxtapositions result in optical illusions (especially when viewed from a distance), revealing a multitude of illusionary geometric forms and illustrating some of the challenges and limitations of perception.
The corners of each face of the two rhombohedra are approximately 23.4 degrees off orthogonal, and the longest axis of each rhombohedron is tilted approximately 23.4 degrees off vertical, referencing the current axial tilt of the earth. Axial tilt is a primary determinant of global climate. From some perspectives the sculpture's tilt creates an illusion that the sculpture is "defying gravity" because the anchoring mechanism cannot be viewed directly. The need to infer rather than being able to view directly is common in science.
Acknowledging that the original function of the Laboratory was to house astronomy activities, the eight tapered rods reference the eight planets of our solar system, as do the eight hexahedra and the eight-fold cascade of the infinity pool described below.
Paying homage to the historic coelostat/solar telescope housed within the Laboratory, each of the tapered rods is painted in bands representing the original seven spectral colors designated by Isaac Newton in 1671. The relative locations and widths of the bands, as well as the relative diameters of the rods at the midpoint of each band, correspond to the respective wavelengths of light represented by the seven colors. The relative spacings between the bands correspond to wavelength differences between the seven spectral colors.
The outer rhombohedron is an expanded version of the inner rhombohedron, both of which emanate from the common "virtual nucleus," thus alluding to expansion of the universe. The inner rhombohedron is painted violet, and the outer rhombohedron is painted red, so as (in exaggerated terms) to connote the red shift of an expanding universe. The two rhombohedra also reference the rhombohedral lattice system of calcite, an important mineral in studies of the history of our global environment.
The aluminum rod structure rises from an "island" surrounded by a black, solar-powered, recirculating infinity pool. Black is the color that results from combining all seven spectral pigment colors from the upper part of the sculpture. Based on their positions relative to the infinity pool, the upper part of the sculpture and the island can be perceived as representing the emergence of life from the oceans or, alternatively, as matter being drawn into a black hole. The black pool also connotes dark matter (first inferred in 1933 by Caltech's Fritz Zwicky) and dark energy of the universe.
As with the edges of the outermost rhombohedron, the length of each side of the island is equal to one ten-millionth of the diameter of Earth along its axis of rotation. The outer dimensions of the horizontal pool surface relative to those of the island are determined by phi, as are the respective elevations of the pool and the island relative to the patio surface. The point of emergence of the aluminum structure from the island is the point in space that divides both the island and the pool each into the Golden Ratio, connoting a metaphysical axis mundi.
The pool provides opportunities to sense the dispersion and interaction of water flows and to observe the impact of wind and rain upon the surface. The cyclical water flow rate profile references climate cycles and other periodic natural phenomena, and is programmed to extend phi into the time dimension. Depending on the angle of the sun, reflections from the surface of the flowing water create illusions of internal motion in individual aluminum rods. The entire aluminum rod structure acts like an array of intersecting sundials. The array casts changing geometric shadow patterns that evidence the time-dependent rotational position of Caltech relative to the sun. As shadows cross the black pool, they sometimes become more difficult to observe - once again illustrating the vagaries of perception.
PERCEPTION contains yet other allusions and illusions that perceptive observers may discover.
PERCEPTION contains various allusions in addition to those specifically mentioned in the Artist's Statement that accompanies the sculpture. Only one of these additional allusions, however, matches all of the clues contained in the Statement of Clues below.
If Sherlock Holmes, the fictional master of perception, had been a member of the Caltech community, he would not have needed a dozen clues to discover the allusion. At the time of discovery he characteristically would have exclaimed, "Elementary, my dear Watson!"
Science has progressed enormously since Robinson Laboratory was built. Now the Global Environmental Science initiative will provide a rare opportunity for Caltech's divisions, working in concert and in parallel, to address an impending crisis that faces our planet.
With nearly one month left in the contest, two people correctly identified the number 12 as representing allusions contained in PERCEPTION, but neither identified the correct reference contained in the Statement of Clues that led to that number or the specific allusion that matches all of the clues. Identifying the specific clues in the Statement of Clues will lead to an observation in the history of science.
The Caltech Community has been stumped and, as a result, $1,000 has been added to the endowment for global environmental science. No one in the Caltech Community came forward within one year with the correct answer to the contest that was announced on January 24, 2012 by alumnus and Vice Chair of Caltech's Board of Trustees, Ronald Linde, at the dedication of Linde+Robinson Laboratory.
Several members of the Caltech community submitted very insightful entries that correctly identified hidden allusions contained in PERCEPTION, and several of the clues were correctly identified. None of the entrants, however, identified the specific allusion that matches all of the clues, as required by the contest rules. Below is the solution:
Solution: The number of parallel hexahedron faces (12) in PERCEPTION equals the number of rare earth elements discovered since Robinson Laboratory was built in 1932. The number of different clues also is 12.
Details: Clues contained in the 'Statement of Clues' are identified below by underlining, with explanations (where deemed helpful) in brackets and red type.
STATEMENT OF CLUES
History [of science and of Caltech] and Mystery: A Number  of Clues for a Test in PERCEPTION
If Sherlock Holmes, the fictional master of perception, had been a member of the Caltech [Caltech's history] community, he would not have needed a dozen [12 parallel faces/12 discoveries] clues to discover the allusion. At the time of discovery he characteristically would have exclaimed, "Elementary [pertaining to elements], my dear Watson!"
Science has progressed enormously since Robinson Laboratory was built. Now the Global Environmental Science initiative will provide a rare opportunity for Caltech's [same clue as above] divisions, working in concert and in parallel, to address an impending crisis that faces our planet [Earth].