Quantum Mechanics is a fundamental physical theory about atomic-scale processes. It was built between 1920 and 1940 by the most distinguished physicists of that time. The accordance between the predictions of the theory and experimental results is remarkable. The physical interpretation of its mathematical constructs, however, raised unprecedented controversies. Ontological, semantic, and epistemic vagueness abound in the orthodox interpretations and have resulted in serious misunderstandings that are often repeated in textbooks and elsewhere. In this work, we identify, criticize, and clarify (...) the most spread ones. (shrink)

Macroscopic irreversible processes emerge from fundamental physical laws of reversible character. The source of the local irreversibility seems to be not in the laws themselves but in the initial and boundary conditions of the equations that represent the laws. In this work we propose that the screening of currents by black hole event horizons determines, locally, a preferred direction for the flux of electromagnetic energy. We study the growth of black hole event horizons due to the cosmological expansion and accretion (...) of cosmic microwave background radiation, for different cosmological models. We propose generalized McVittie co-moving metrics and integrate the rate of accretion of cosmic microwave background radiation onto a supermassive black hole over cosmic time. We find that for flat, open, and closed Friedmann cosmological models, the ratio of the total area of the black hole event horizons with respect to the area of a radial co-moving space-like hypersurface always increases. Since accretion of cosmic radiation sets an absolute lower limit to the total matter accreted by black holes, this implies that the causal past and future are not mirror symmetric for any spacetime event. The asymmetry causes a net Poynting flux in the global future direction; the latter is in turn related to the ever increasing thermodynamic entropy. Thus, we expose a connection between four different “time arrows”: cosmological, electromagnetic, gravitational, and thermodynamic. (shrink)

The verb “to conjure” is a complex one, for it includes in its standard definition a great range of possible actions or operations, not all of them equivalent, or even compatible. In its most common usage, “to conjure” means to perform an act of magic or to invoke a supernatural force, by casting a spell, say, or performing a particular ritual or rite. But “to conjure” is also to influence, to beg, to command or constrain, to charm, to bewitch, to (...) move or convey, to imagine, to visualize, to call to mind, or to remember. —Rachael DeLue 2012, para 1. When we create with our Brown hands, feminine energy, and full spirits, we conjure. To exist, survive, and thrive in these bodies is a continuous act of conjuring. Our walks conjure. Our smiles conjure. Our tears conjure. Our laughs conjure. Our words conjure. Our artworks are conjurings. We, a Black/Filipina-American woman, a Dominican-American, and a Black-American woman, are guided by our solidarity with one another and all other Black and Brown female identifying persons whose raced and gendered subjectivities exist both inside and outside of colonization, white supremacy, and patriarchy. We bring to life our colored imaginations and curiosities, and share them with the world. We are united by our need for safety, autonomy as beings, dissolution of trauma, and desire to ask, “What would happen if I…?” Imaginative, curious Women of Color (WoC) founded the underground railroad, guided captured Africans and Tainos to the mountains, ignited the Civil Rights Movement, organized laborers and immigrants, birthed the #BlackLivesMatter Movement, conceived the #MeToo Movement, and so much more. Like our kindred counterparts, we have an unrelenting urge to examine, question, wonder, desire, speak to, lead, be curious, and “conjure.” As practicing artists and art educators, our critical arts-based practices are grounded in intersectional feminisms like Womanism, Black Feminist Theory, and Chicana Feminist Theory, which allow us to do these very things. (shrink)

The main thesis of this dissertation is set out in its very title, and to prove it will be necessary to eliminate the usual negative or melodramatic meaning of the two concepts that appear there and take them rather as the two extremes of the dialectical process of redefining the sociopersonal consciousness. In accordance with this, any catastrophe implies the violent breakup of the normal conditions of existence due to a natural or human factor whose direct consequences each one must (...) understand and overcome on the triple ontological, social, and psychological determinations of the self. For its part, tragedy stands for the phase of critical and reflective integration that follows the catastrophe, which goes a lot beyond the sheer negativity of sorrow and even death, since even if the person or the people carried away by the catastrophe die, others will be able to make the most of that and the sociopersonal consciousness will be rearticulated. Of course, this implies that the self at issue is not only the individual one, so that other members of the lifeworld must be considered for the phenomenon to reveal a new or critical sense of existence beyond any previous approach to it. Thus, although there is an undeniably negativity throughout, it aims at a deeper level of comprehension of existence, which finally implicates that catastrophe is contextualized in a concrete cultural framework and not only as a sudden unsettlement and that tragedy is accordingly conceived as a philosophical tool more than as a literary genre that deals with the cruelty of fate. To get its aims, the dissertation will be divided into three sections of variable length: in the first one it will be analysed the experience and sense of catastrophe; in the second one, that of tragedy; in the third one, it will briefly be shown why understanding the nexus of both phenomena is axial for the current intellectual dynamics. (shrink)

A conservative extension of first order logic, suitable for circumscriptive inference, is introduced.

Given that there is referential uncertainty (noise) when learning words, to what extent can forgetting filter some of that noise out, and be an aid to learning? Using a Cross Situational Learning model we find a U-shaped function of errors indicative of a “Goldilocks” zone of forgetting: an optimum store-loss ratio that is neither too aggressive or too weak, but just the right amount to produce better learning outcomes. Forgetting acts as a high-pass filter that actively deletes (part of) the (...) referential ambiguity noise, retains intended referents, and effectively amplifies the signal. The model achieves this performance without incorporating any specific cognitive biases of the type proposed in the constraints and principles account, and without any prescribed developmental changes in the underlying learning mechanism. Instead we interpret the model performance as more of a by-product of exposure to input, where the associative strengths in the lexicon grow as a function of linguistic experience in combination with memory limitations. The result adds a mechanistic explanation for the experimental evidence on spaced learning and, more generally, advocates integrating domain-general aspects of cognition, such as memory, in to the language acquisition process. (shrink)

From March to September 2020, researchers working at a biomedical scientific campus in Spain faced two lockdowns and various mobility restrictions that affected their social and professional lifestyles. The working group “Women in Science,” which acts as an independent observatory of scientific gender inequalities on campus launched an online survey to assess the impact of COVID-19 lockdowns on scientific activity, domestic and caregiving tasks, and psychological status. The survey revealed differences in scientific performance by gender: while male researchers participated in (...) a larger number of scientific activities for career development, female researchers performed more invisible scientific tasks, including peer review or outreach activities. Mental impact was greater in researchers caring for children or dependents, and this was aggravated for women. Results spot a disproportionate impact of COVID-19 lockdowns on female scientific career development, and urges for equity measures to mitigate the consequences of an increase in the gender gap in biomedical sciences for current and future pandemics. (shrink)

It is widely believed that a person's traits can function as reasons for loving her. Notable contemporary work in the philosophy of love has taken the rejection of this premise as its point of departure. As far as I can tell, none of that work has engaged with a careful philosophical exposition of the view under discussion. In the following pages, I will defend the idea of trait-based love against three of its critics and one of its advocates. I will (...) discuss work on this topic by Harry Frankfurt, Niko Kolodny and David Velleman, arguing that their criticisms fail and that the alternatives they offer to trait-based love create more difficulties than they solve. What these authors have in common is a deflationary approach to love that reduces it to a beneficent disposition, a valuing relationship and a visceral form of moral regard, respectively. I will compare these to the multiplex, nuanced depiction of trait-based love in Plato's Symposium. While it is plausible that love can motivate a beneficent disposition, develop in relationships and entails moral regard, I will argue that the attempt to reduce it to any of the foregoing fails. Frankfurt, Kolodny and Velleman reject trait-based love in part because they think it would differ in unacceptable ways from the love most of us practice. Plato advocates the cultivation of a love that in some respects resembles the picture of trait-based love the contemporary authors balk at. However, unlike those critics, he appreciates that trait-based love need not resemble the ideal he proposes. His richer view of love accounts for elements such as need and feeling that the contemporary thinkers are driven to implausibly bracket as distractions. As I will try to show, the most compelling criticisms of Platonic love do not tell against its responsiveness to the loved one's traits. I will argue that trait-based love is consistent with an intuitive picture of love and that this commonsense approach is more defensible than competing views in these texts. These authors' disagreements about what can count as reasons for love are bound up with the differences in what each takes love to be. Thus, in the course of arguing for trait-based love, I will critically assess their various proposals as to the nature of love. (shrink)

Abstract“The Book of Secrets in the Results of Ideas”, usually called “The Book of Secrets” is a codex containing drawings and descriptions of thirty-one artifacts attributed to the engineer Alī Ibn Khalaf al-Murādī, who lived in Andalusia in southern Spain at the beginning of the 11th century. This manuscript is one of the first written testimonies that describe medieval mechanisms with complex precision. The aim of this work is to reconstruct and study from a historical and technological point of view (...) two of the ancient artifacts contained in the “Book of Secrets”, the “Fortress Demolisher” and the “Magic Well”. The “Fortress Demolisher” is a war machine designed to demolish the upper part of the walls or towers and consists of a battering ram mounted on a platform that can be raised several meters above the ground using a scissor mechanism. The “Magic Well” is a mechanism with several pulleys whose purpose is to raise water several meters from the bottom of a well by collecting a small portion of rope. To reconstruct the two artifacts, a digital model and a detailed study of the geometry and operation of the mechanisms, were first carried out. 3D printing, using the Fused Deposition Modelling technology, made the physical reproduction. The digitization and physical reproduction by 3D printing of the mechanisms represent an update of the traditional ways of transmitting knowledge. The use of these new technologies makes the knowledge more accessible, understandable and attractive. (shrink)

My theme in this essay is the relation of misfortune – and other occasions for regret – to the affirmation of life. R. Jay Wallace believes there is an antagonistic relation that produces a schism between our affirmative attitudes and our reasons and considered judgments. On his view, our attachments to the persons and projects that give meaning to our lives lead us to affirm states of affairs it would be more appropriate to regret. I argue that the attitude of (...) affirmation can acknowledge and do justice to reasons for regret. Wallace fails to appreciate the implications of the Nietzschean positions he cites as precedents; he assumes the past has a meaning that is fixed and insulated from the future. Drawing on Nietzsche, I argue that the affirmation of life is a coherent project of bestowing meaning on a historical sequence going forward into the future. (shrink)

A substantial body of recent philosophy envisages a close, congenial relationship between blame and morality. It has been posited, assumed or argued, for instance, that blame is responsive to moral...

The first European settlements in the new world faced technical issues with the help of the XVI century scientific advances. Besides briefly exposing the scientific and technological situation, this paper explores, with the help of reverse engineering, two singular mechanical wits representative of the technological advances introduced in America to overcome different problems. Firstly, a pump, based on an alternative movement system through crankshafts and pistons used against the continuous flooding suffered in the Ciudad de México valley. Although flooding remained (...) a problem (it was solved in the XX century), hydraulic pumps were essential for continuous soil drainage. Secondly, a port crane for handling cannons, military devices, and construction materials during the Lima fortification in the XVII century. For both cases, reverse engineering, through engineering methods, Computer-Aided Design CAD programs, and additive manufacturing, provides virtual and/or tangible mockups that help to analyze and improve our knowledge about the dimensions, materials, and functions of used (and currently lost) mechanical systems during the American colonization. (shrink)

An extension of the Quantified Propositional Calculus1 obtained by the addition of two binary propositional functions is put forward as an inheritor of E. Schröder's “Algebra der Logik”. The formal system is itself not new, in fact it forms part of A. P. Morse's “A Theory of Sets”; although the latter is considered as a first-order system. Since the additional propositional functions are not invariant under the logical biconditional, this system–and many others naturally obtained from it–give us a collection of (...) examples of non-standard, but mathematically meaningful, propositional systems. (shrink)

A reduction algebra is defined as a set with a collection of partial unary functions (called reduction operators). Motivated by the lambda calculus, the Church-Rosser property is defined for a reduction algebra and a characterization is given for those reduction algebras satisfying CRP and having a measure respecting the reductions. The characterization is used to give (with 20/20 hindsight) a more direct proof of the strong normalization theorem for the impredicative second order intuitionistic propositional calculus.

The present essay looks to add to the body of literature that seeks to clarify the nature of vengeance and evaluate it morally. However, unlike previous philosophical investigations of vengeance, my essay examines it not from the standpoint of impersonal justice but from the perspective of the one who seeks it, to determine whether it is good for the would-be avenger. The values I measure it by are fulfillment and self-knowledge. The paper has two major parts. In the first, I (...) argue that vengefulness is motivated by two ends: allaying a sense of vulnerability and preserving a positive self-conception. The emotional benefits of a vengeful disposition, I claim, come at the expense of self-knowledge. They are therefore unstable and prone to give way when vengefulness is translated into action. In the second part, I try to substantiate this claim by examining two criticisms of vengeance: that its pursuit can diminish the avenger by consuming him and that it is self-defeating. Framing vengefulness within broader psychoanalytic accounts of the repetition compulsion and projection, I endorse versions of both criticisms that tie vengeance’s failure to provide fulfillment to some of the ways in which it occludes self-knowledge. (shrink)