8 research outputs found
Evo-SETI: life evolution statistics on Earth and exoplanets
No full textThis book offers a vision of how evolutionary life processes can be modelled. It presents a mathematical description that can be used not only for the full evolution of life on Earth from RNA to modern human societies, but also the possible evolution of life on exoplanets, thus leading to SETI, the current Search for ExtraTerrestrial Intelligence. The main premise underlying this mathematical theory is that the Geometric Brownian Motion (GBM) can be applied as a key stochastic process to model the evolution of life. In the resulting Evo-SETI Theory, the life of any living thing (a cell, an animal, a human, a civilization of humans, or even an ET civilization) is represented by a b-lognormal, i.e., a lognormal probability density function starting at a precise instant (b, birth) then increasing up to a peak time, then decreasing to senility time and then continuing as a straight line down to the time of death. Using this theory, Claudio Maccone arrives at remarkable hypotheses on the development of life and civilizations, the possibility of extraterrestrial life, and when computers will take over the reins from us humans (Singularity). The book develops the mathematical Evo-SETI Theory by integrating a set of articles that the author has published in various journals on Astrobiology and Astronautical Research
Feeding behaviour related to different feeding devices
No full textSlow feeding devices (SFDs) are useful tools in order to improve the horse wellbeing
and to reduce wastage, but their use may result in unnatural posture
during feeding and frustration behaviours. Moreover, it may be important to
evaluate the laterality during feeding. The aim of the study was to investigate
ponies' feeding behaviour (i.e., lateralisation, frustration, postural eating style)
with different hay feeding methods: on the ground (G), a fully filled hay net (HF),
a partially filled hay net (HL), and a slow feeder hay box (HB). Nine ponies of two
different breed types (Shetland and Welsh/Cob) were evaluated. Video
recordings were obtained and then behavioural analysis was conducted. Data
were analysed statistically using k‐means cluster analysis, repeated measurement
mixed model procedure, principal component analysis (PCA) and Pearson's
correlation coefficient. Head tilting was more often performed during feeding
from HF and HL compared to G and HB. Forelimb forward, referring to the
position that ponies assumed during feeding, was performed less frequently
with the hay nets. Ponies, in particular Welsh/Cobs, tended to be more leftlateralized
and performed more backward ears when feeding from the hay
nets. Blink rate was observed to be greater when ponies were fed from G.
No head pushing, striking with forelimb and pawing while feeding was seen.
Animals fed from HF tended to eat from the top of the hay net and
consequently showed an arched neck; while HL and HB showed for elongated
neck an intermediate pattern between G and HF. From our results, HB seemed
to be a useful compromise between natural feeding on the ground and the use
of hay nets
Deep Space Flight and Communications: Exploiting the Sun as a Gravitational Lens
No full textThe majority of books dealing with prospects for interstellar flight tackle the problem of the propulsion systems that will be needed to send a craft on an interstellar trajectory. The proposed book looks at two other, equally important aspects of such space missions, and each forms half of this two part book. Part 1 looks at the ways in which it is possible to exploit the focusing effect of the Sun as a gravitational lens for scientific missions to distances of 550 AU and beyond into interstellar space. The author explains the mechanism of the Sun as a gravitational lens, the scientific investigations which may be carried out along the way to a distance of 550 AU (and at the 550 AU sphere itself), the requirements for exiting the Solar System at the highest speed and a range of project ideas for missions entering interstellar space. Part 2 of the book deals with the problems of communicating between an interstellar spaceship and the Earth, especially at very high speeds. Here the author assesses a range of mathematical tools relating to the Karhunen-Loève Transform (KLT) for optimal telecommunications, technical topics that may one day enable humans flying around the Galaxy to keep in contact with the Earth. This part of the book opens with a summary of the author’s 2003 Pešek Lecture presented at the IAC in Bremen, which introduces the concept of KLT for engineers and ‘newcomers’ to the subject. It is planned to include a DVD containing the full mathematical derivations of the KLT for those interested in this important mathematical tool whilst the text itself will contain the various results without outlines of the mathematical proofs. Astronautical engineers will thus be able to see the application of the results without getting bogged down in the mathematics
Mathematical SETI: Statistics, Signal Processing, Space Missions
No full textThis book introduces the Statistical Drake Equation where, from a simple product of seven positive numbers, the Drake Equation is turned into the product of seven positive random variables. The mathematical consequences of this transformation are demonstrated and it is proven that the new random variable N for the number of communicating civilizations in the Galaxy must follow the lognormal probability distribution when the number of factors in the Drake equation is allowed to increase at will. Mathematical SETI also studies the proposed FOCAL (Fast Outgoing Cyclopean Astronomical Lens) space mission to the nearest Sun Focal Sphere at 550 AU and describes its consequences for future interstellar precursor missions and truly interstellar missions. In addition the author shows how SETI signal processing may be dramatically improved by use of the Karhunen-Loève Transform (KLT) rather than Fast Fourier Transform (FFT). Finally, he describes the efforts made to persuade the United Nations to make the central part of the Moon Far Side a UN-protected zone, in order to preserve the unique radio-noise-free environment for future scientific use
A first contribution to the history of Italian SETI
No full textThe first seminal paper about SETI, Searching for Interstellar Communications, published in Nature on 19 September 1959, was written by an American author, Philip Morrison, and another Italian, Giuseppe Cocconi. Nonetheless, from then on, for 30 years Italy has not taken part in the research that arose from that article. But in 1990 two Italian guys, Claudio Maccone and Stelio Montebugnoli, met while participating in the Bioastronomy meeting held in Val Cenis, and the history of Italian SETI began. From then on, the contributions by Italian investigators to search for extraterrestrial civilizations have constantly increased, both in number and quality, but so far nobody had tried to tell their history. In 2024, on the occasion of the IAC Milano 2024, a first contribution appeared, in a book written by myself (“Ascoltando l’infinito silenzio. L’Italia e la ricerca delle civiltà extraterrestri”), but which could count on several contributions from the main protagonists of Italian SETI. In this paper I present the main topics covered in the book and the possible future developments of this work
Quantum interference and manipulation of entanglement in silicon wire waveguide quantum circuits
No full textIntegrated quantum photonic waveguide circuits are a promising approach to realizing future photonic quantum technologies. Here, we present an integrated photonic quantum technology platform utilizing the silicon-on-insulator material system, where quantum interference and the manipulation of quantum states of light are demonstrated in components orders of magnitude smaller than previous implementations. Two-photon quantum interference is presented in a multi-mode interference coupler, and the manipulation of entanglement is demonstrated in a Mach–Zehnder interferometer, opening the way to an all-silicon photonic quantum technology platform
Quantum detector tomography of a time-multiplexed superconducting nanowire single-photon detector at telecom wavelengths
No full textSuperconducting nanowire single-photon detectors (SNSPDs) are widely used in telecom wavelength optical quantum information science applications. Quantum detector tomography allows the positive-operator-valued measure (POVM) of a single-photon detector to be determined. We use an all-fiber telecom wavelength detector tomography test bed to measure detector characteristics with respect to photon flux and polarization, and hence determine the POVM. We study the SNSPD both as a binary detector and in an 8-bin, fiber based, Time-Multiplexed (TM) configuration at repetition rates up to 4 MHz. The corresponding POVMs provide an accurate picture of the photon number resolving capability of the TM-SNSPD
Quantum-enhanced dark matter detection with in-cavity control: mitigating the Rayleigh curse
No full textPublisher Copyright: © The Author(s) 2025.The nature of dark matter is a fundamental puzzle in modern physics. A major approach of searching for dark matter relies on detecting feeble noise in microwave cavities. However, the quantum advantages of common quantum resources such as squeezing are intrinsically limited by the Rayleigh curse—a constant loss places a sensitivity upper bound on these quantum resources. In this paper, we propose an in situ transient control to mitigate such Rayleigh limit. The protocol consists of three steps: in-cavity quantum state preparation, axion accumulation with tunable time duration, and measurement. For the quantum source, we focus on the single-mode squeezed state (SMSS), and the entanglement-assisted case using signal-ancilla pairs in two-mode squeezed state (TMSS), where the ancilla does not interact with the axion. From quantum Fisher information rate evaluation, we derive the requirement of cavity quality factor, thermal noise level and squeezing gain for quantum advantage. When the squeezing gain becomes larger, the optimal axion accumulation time decreases, which reduces loss and mitigates the Rayleigh curse—i.e., the quantum advantage increases with the squeezing gain. Overall, we find that TMSS is more sensitive in the low-temperature limit. In the case of SMSS, as large gain is required for an advantage over vacuum, homodyne detection is sufficient to achieve optimality. Whereas, for TMSS, anti-squeezing and photon counting is optimal. Thanks to recent advances in magnetic field-resilient in-cavity squeezing and rapidly coupling out for photon counting, the proposed protocol is compatible with axion detection scenario.Peer reviewe
