Charles Kindleberger

Minimalist economists stubbornly resist Charles Kindleberger's characterization of investor expectations in a financial bubble as "irrational." This paper seeks to resolve the controversy by imbedding Kindleberger's well-researched, impressionistic theory of financial crises into an expanded, but still-minimalist model of rational expectations. Introducing the concepts of malicious disinformation and rational overpromotion creates an informational environment in which it is time-consuming and costly to distinguish fact from fiction. Rationality still requires that expectations and market fundamentals move together over long periods of time, but dishonorable overpromoters can earn substantial profits in the interim.

Stroke Based Painterly Rendering

International audienceMany traditional art forms are produced by an artist sequentially placing a set of marks, such as brush strokes, on a canvas. Stroke based Rendering (SBR) is inspired by this process, and underpins many early and contemporary Artistic Stylization algorithms. This Chapter outlines the origins of SBR, and describes key algorithms for placement of brush strokes to create painterly renderings from source images. The chapter explores both local greedy, and global optimization based approaches to stroke placement. The issue of creative control in SBR is also briefly discussed

Turbulent luminance in impassioned van Gogh paintings

We show that the patterns of luminance in some impassioned van Gogh paintings display the mathematical structure of fluid turbulence. Specifically, we show that the probability distribution function (PDF) of luminance fluctuations of points (pixels) separated by a distance R compares notably well with the PDF of the velocity differences in a turbulent flow, as predicted by the statistical theory of A.N. Kolmogorov. We observe that turbulent paintings of van Gogh belong to his last period, during which episodes of prolonged psychotic agitation of this artist were frequent. Our approach suggests new tools that open the possibility of quantitative objective research for art representation

Deepening inside the pictorial layers of Etruscan sarcophagus of Hasti Afunei: An innovative micro-sampling technique for Raman/SERS analyses

The Hasti Afunei sarcophagus is a large Etruscan urn, made up of two chalky alabaster monoliths. Dated from the last quarter of the third century BC, it was found in 1826 in the small town of Chiusi (Tuscany- Il Colle place) by a landowner, Pietro Bonci Casuccini, who made it part of his private collection. The noble owner’s collection was sold in 1865 to the Royal Museum of Palermo (today under the name of Antonino Salinas Regional Archaeological Museum), where it is still displayed. The sarcophagus is characterized by a complex iconography that is meticulously illustrated through an excellent sculptural technique, despite having subjected to anthropic degradation and numerous restorative actions during the last century. During the restoration campaign carried out between 2016 and 2017, a targeted diagnostic campaign was carried out to identify the constituent materials of the artefact, the pigments employed and the executive technique, in order to get an overall picture of conservation status and conservative criticalities. In particular, this last intervention has allowed the use of the innovative micro-sampling technique, patented by the Cultural Heritage research group of Sapienza, in order to identify the employee of lake pigments through SERS analyses. Together with this analysis, Raman and NMR technique have completed the information requested by restorers, for what concerns the wax employed as protective layers, and allowed to rebuild the conservation history of the sarcophagus. In fact, together with the identification of red ocher and yellow ocher, carbon black, Egyptian blue and madder lake, pigments compatible with the historical period of the work, modern pigments (probably green Paris, chrome orange, barium yellow, blue phtalocyanine) have been recognized, attributable with not documented intervention during the eighteenth and twentieth centuries. © 2019 by the authors

The Art of Seeing and Painting

The human urge to represent the three-dimensional world using two-dimensional pictorial representations dates back at least to Paleolithic times. Artists from ancient to modern times have struggled to understand how a few contours or color patches on a flat surface can induce mental representations of a three-dimensional scene. This article summarizes some of the recent breakthroughs in scientifically understanding how the brain sees that shed light on these struggles. These breakthroughs illustrate how various artists have intuitively understand paradoxical properties about how the brain sees, and have used that understanding to create great art. These paradoxical properties arise from how the brain forms the units of conscious visual perception; namely, representations of three-dimensional boundaries and surfaces. Boundaries and surfaces are computed in parallel cortical processing streams that obey computationally complementary properties. These streams interact at multiple levels to overcome their complementary weaknesses and to transform their complementary properties into consistent percepts. The article describes how properties of complementary consistency have guided the creation of many great works of art.National Science Foundation (SBE-0354378); Office of Naval Research (N00014-01-1-0624

Storytelling through Impressionist Music and American Sign Language: The Engulfed Cathedral

“The Legend of the City of Ys” is a Breton story of a city’s downfall and curse to be swallowed by the sea. Years later, this tragic tale inspired “The Engulfed Cathedral,” a piano composition for Claude Debussy’s Preludes, Book I, L. 117. Following analyses of “The Legend of the City of Ys” and “The Engulfed Cathedral,” an interpretation of the narrative was created in American Sign Language to be performed with the music. The goal is to focus on inclusivity and accessibility in music for Deaf and hard of hearing individuals, and then expand that to consider how to bridge the divide between Deaf and hearing communities. This project illustrates that storytelling is a core aspect of the human experience that transcends boundaries and connects people despite their differences. By exploring a story through different modes of communication, the aptitudes and limitations of each medium can be assessed, and the value of diverse forms of expression can be recognized

Do music and art influence one another? Measuring cross-modal similarities in music and art

The visual arts and music interact with one another on both an individual scale (e.g., music-inspired synesthetes and artist-musician duos) and on a grand scale (e.g., the art movement Baroque, wherein abstract qualities such as “ornamentation” permeate both media). We develop a means to measure one of the many cross-modal similarities between music and visual art to both reveal any direct influences between the media, and to apply them to determine whether these connections became stronger or weaker throughout time. We examined the cross-modally linked continuums of lightness of color and height of pitch within comparable paintings and music of a time-determined art movement. The model of comparison extracted, measured, and contrasted the attributes of lightness of color in art and height of pitch in music in works from Russia and France created between 1870 and 1920. Although Russian visual art was measurably darker in value than French visual art of the same time, no significant differences were found between Russian and French music. While our results do not suggest direct influences manifesting differently in each medium, they demonstrate the use of the lightness-pitch model, applicable to other eras to measure potential cross-modal convergence and divergence through time