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The term 'neutrinoless' is a cornerstone of modern particle physics, yet it defines a fundamental process by what is missing rather than what is created. We trace the origins of this privative neologism to a 1953 experimental claim and show how a 'sociology of suspicion' transformed Ettore Majorana's affirmative ontology into an agnostic shorthand. By examining this linguistic shift, we argue that our current terminology may obscure the profound physical meaning of the search. Reclaiming the language of 'matter creation' is not merely a semantic choice, but a timely conceptual shift to bridge the gap between experimental caution and the radical character of the laws of nature we aim to uncover.
The concept of antimatter is extremely important, but not always discussed as it deserves, balancing ideas and formalism. In this note, we gather some insights to present it effectively, following certain steps taken in the history of knowledge; although rarely remembered, they can serve to enrich standard teaching materials. In addition to the well-known contributions of Dirac, which we place in their original context, the contributions of Pauli and especially Majorana stand out, the latter being the first to reach the modern formalism of canonical quantization. The importance of the point of view of wave mechanics emerges, which still shows its limitations, requiring some adjustments to constitute an acceptable interpretation.
Traditionally, Electromagnetism is taught following the chronological development of the matter. The final product of this path is a presentation of Electromagnetism realized by adding one layer over another with the risk of transferring concepts and formulae from Electrostatics to Electrodynamics. In this paper, we suggest a new approach based on the idea that the matter should be presented within the conceptual framework of Maxwell-Lorentz-Einstein Electromagnetism. This approach is founded on the concept of a field as a primary theoretical entity and on the statement that a point charge produces, in general, an electric and a magnetic field and that the force exerted by these fields on a point charge is the Lorentz's force. Developing this idea, one finds that macroscopic laws corroborated by experiments have a microscopic origin. It also follows that the electromotive force induced in a closed conducting circuit must be defined as the line integral of Lorentz's force on a unit positive charge. This definition leads to a local law of electromagnetic induction, Lorentz's invariant for rigid and filiform circuits. This law contrasts with what Feynman labeled as the "flux rule" - g
In this essay, I discuss an interdisciplinary science that is just blossoming: that of geo-neutrinos. I begin with a couple of episodes from the history of thought, showing the deep roots of Earth science and its many connections with microphysics. I then recall the stage of full maturity reached in the knowledge of neutrinos, which allows one to argue the full reliability of recent measurements. I conclude with a discussion of the state of the field and its prospects for the near future, and with a dedication to the memory of a colleague and friend, Giovanni Fiorentini, a pioneer of these studies.
The year 1953 is pivotal for computational physics: the first application of the Monte-Carlo method is published and calculations of the so-called Fermi-Pasta-Ulam-Tsingou experiment are started. It is the beginning of the massive use in the physical sciences of numerical methods implemented on electronic computers and a decisive step in the development of modern nonlinear dynamics. This will lead to an unpredictable development during the following 70 years. We briefly review the unfolding of these events and present some recent results that show how the issues raised are still relevant today
Ultrafast X-rays revealed how a molecule converts absorbed light into motion in just trillionths of a second。 Individual atoms recorded different stages of the process, opening a powerful new window into light-driven chemistry
Primordial black holes may occasionally pass through white dwarf stars and trigger enormous Type Ia supernova explosions。 Researchers found that these events could explain chemical patterns seen in supernova remnants, nearby explosions, and stars across the Milky Way
A new nanostructured carbon design lets fuel-cell catalysts use tiny amounts of platinum while remaining remarkably stable and efficient。 The breakthrough could help hydrogen fuel cells become a more practical way to power data centers, vehicles, and other energy-intensive technologies
There's no evidence the truck will be a cheap EV truck, but what if it were
Scientists have created an “electron lighthouse” that uses laser light to launch and steer electrons through a semiconductor without an applied electrical field。 The quantum effect could eventually improve optical sensors, communications, imaging, and information storage
A ten-month Antarctic experiment found that astronauts may struggle not only with loneliness but also with spending too much time around the same people。 Frequent contact was linked to greater tension and mistrust, while the crew increasingly divided into cultural and language-based groups
Researchers have found a way to build much larger “twisted” oxide materials while precisely controlling how their atomic layers line up。 Because these materials can be made over large areas and transferred onto different surfaces, the technique could help turn twistronics from a laboratory curiosity into a practical platform for next-generation ele
When atomic nuclei smash together at nearly the speed of light, they create the hottest fluid in the universe, but scientists may have overlooked one of its most important forces。 New simulations reveal that extreme acceleration builds up along the edges of quark-gluon plasma, helping drive its explosive expansion。 This acceleration may do far more
A rare meteorite that crashed through a New Jersey roof contains evidence of ancient salty fluids, organic compounds, and amino acids from a primitive asteroid。 Its pristine chemistry could offer new clues about how space rocks helped supply early Earth with some of the ingredients needed for life
A massive magma reservoir has been detected deep beneath Tuscany, despite showing no obvious signs at the surface。 Scientists mapped the roughly 6,000-cubic-kilometer body using natural ground vibrations recorded by dozens of seismic sensors。 It poses no immediate danger, but the discovery reveals how enormous volcanic systems can remain hidden and
NASA’s Psyche spacecraft aced its Mars flyby, using the planet’s gravity to speed toward its 2029 encounter with a metal-rich asteroid。 The spacecraft tested its cameras, magnetometer, and particle-detecting instruments, capturing unusual views of Mars and measuring its magnetic environment。 It also detected neutrons from the planet and spotted the
Scientists have created the first quantum material that can sort and transport different quantum states of light at room temperature, potentially removing the need for bulky, ultra-cold refrigeration systems。 Built from a gold film carved with hundreds of microscopic structures, the ultrathin “metacrystal” acts like a filter that directs different
Six deaths reported among screwworm cases, one directly attributed to the flies