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By DeepSkyExplorer
Hey everyone, I just came across some recent reports from the All-domain Anomaly Resolution Office (AARO) regarding various military encounters with UAPs. The findings are available through a government document search at war.gov, and it's fascinating to read about the specifics of these incidents. The reports seem to provide a more structured approach to analyzing these encounters compared to previous attempts, which is a step in the right direction for transparency.
One thing that stood out to me was the emphasis on data collection and the various methods being employed to make sense of these sightings. It’s clear that there’s a serious effort underway to understand what’s out there, especially considering the technology involved in some of these military encounters. I noticed they’re not just looking at visual data but also incorporating radar and other sensor inputs, which could lead to a more comprehensive understanding of these phenomena.
However, while some reports do confirm UAP sightings, they often stop short of identifying what these phenomena actually are, which leaves a lot to speculation. It’s a bit frustrating because we know there are instances where these objects have exhibited capabilities far beyond our current technology. But the reports do seem to be taking a more scientific approach to investigation, which is encouraging.
I’m curious if anyone else has had a chance to dive into these documents? What do you think about the level of detail and the investigation methods being used? Do you feel like we’re getting closer to some real answers, or is this just another round of vague acknowledgments? You can check out the details of these reports on the AARO’s page linked here: https://www.war.gov/UFO/search/uap/. Would love to hear your thoughts on this!
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By Avi Loeb Medium
A 1.5-Solar-Mass Star in a Tight Orbit Around the 4.3-Million Solar-Mass Black Hole at the Milky-Way Center
Time series of the orbits of various stars around the supermassive black hole, SgrA*, at the Milky-Way center, obtained from data by GRAVITY/VLT between 2021 to 2025. The new star S301 arrives within 140 Schwarzschild radii of the black hole where its peak velocity is 8.3% of the speed of light, 25,000 kilometers per second. (Image credit: Abd El Dayem et al. 2026)The fastest moving star, labeled S301, was discovered recently by Stefan Gillessen’s team at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany (as first reported here, with the full paper accessible here). The star was discovered by near-infrared interferometry on 8-meter telescopes, using the GRAVITY instrument in operation at the European Southern Observatory’s (ESO’s) Very Large Telescope (VLT). Last night, I sat next to Stefan at the reception dinner of the annual conference of Harvard’s Black Hole Initiative, for which I served as the founding director a decade ago.
This 1.5-solar-mass star moves on a highly elliptical orbit with a period of 8.7 years and eccentricity of 0.98 around the supermassive black hole at the Milky-Way center, called Sagittarius A*. This black hole has a long history of swallowing 4.3 million solar masses of gas and stars from its environment. The peak velocity of S301 is 25,000 kilometers per second or 8.3% of the speed of light, as it comes down to a distance of 140 times the Schwarzschild radius of the black hole — which defines the scale of the black hole mouth from where even light cannot escape. If the star were to pass ten times closer to the black hole, it would have been ripped apart by tidal gravity into a stream of gas that shines brightly as it feeds the mouth of this spacetime beast.
The orbit of S301 can be used to test expectations from Albert Einstein’s formulation of gravity as the curvature of spacetime. Einstein’s equations predict that S301’s orbit will precess in response to the spin of the black hole, offering a precise new way to measure how fast Sagittarius A* is rotating within the coming decade.
How did this star get so close to the black hole?
A natural mechanism, proposed by Jack Hills in a 1988 paper published here, is the tidal break-up of a pair of stars by the black hole. About half of solar-mass stars form in binaries. When a binary star system gets close enough to the black hole, the tidal gravity becomes strong than the gravitational binding of the two stars and breaks the binary apart, sending one star out at a speed of up to thousands of kilometers per second and launching the second star into a tighter orbit around the black hole. Indeed, a population of hypervelocity stars had been discovered on their way out in the Milky-Way halo by Warren Brown and collaborators from the Harvard-Smithsonian Center for Astrophysics (as reported here).
In a 2006 paper published here, I proposed with the student, Idan Ginsburg, that the former companions of the observed hypervelocity stars in the Milky-Way halo might have produced the observed population of close-in S-stars on highly eccentric orbits around Sagittarius A*. The Galactic center star S301 is likely one of them, formed via the Hills mechanism out of an initial binary star system with an orbital period of 1–2 weeks over the past 100 million years.
In a follow-up paper published here, I showed with Idan that planets could survive the break-up of binary star systems by Sagittarius A*. As a result, Galactic travel agencies could sell tickets for thrilling journeys on habitable planets around hypervelocity stars. I wonder whether adventurous Galactic passengers would prefer to travel with a hypervelocity star on its way out of the Milky-Way galaxy at a speed of up to 1% of the speed of light or travel with a star like S301 as it reaches 8.3% of the speed of light and gets within a distance of 140 Schwarzschild radii from the largest black hole in our Galaxy. I would personally favor the latter, since the extreme spacetime structure of a supermassive black hole is far more exhilarating than the rarefied environment of intergalactic space. The trip close to the black hole also offers health benefits, since aging slows down by a third of a percent at closest approach of S301 to Sagittarius A*. This corresponds to a gain of 5 minutes to the passenger’s lifespan every day relative to distant relatives.
The black hole tour with S301 offers a view of the black hole’s mouth from a distance where it occupies roughly the same angle as the Moon or the Sun on our sky. The gas swirling into the event horizon of Sagittarius A* glows bright but at the center of this glow, there is a silhouette — a shadow cast by the absorption of light emanating behind the black hole. Over the decade between 2006 and 2016, I wrote 30 papers in collaboration with my postdoc, Avery Broderick, forecasting the expected portrait of a black hole (as detailed here and summarized for the general public here). By now, Sagittarius A* was imaged by the Event Horizon Telescope (here), whose headquarters was established at Harvard’s Black Hole Initiative during my directorship.
On a tour with S301, it would be fascinating to observed the silhouette image of Sagittarius A* from a minimum distance that is 140 million times closer than the Earth is from the black hole. I would have loved to serve as the tour guide on such a journey. Here’s hoping that Galactic travel agents would pay attention to this essay.
ABOUT THE AUTHOR
(Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
Professional website:
https://lweb.cfa.harvard.edu/~loeb/
Social media:
https://avi-loeb.medium.com/
https://www.youtube.com/@ProfessorAviLoeb
https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd
https://x.com/ProfAviLoeb
View the full article
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By Avi Loeb Medium
(Image credit: Scientific American)In recent months, two papers (accessible here and here) suggested the existence of an abundant population of negative mass objects in the Universe. Albert Einstein’s theory of gravity, General Relativity, allows negative masses, as discussed in a seminal 1957 paper published here by the physicist Herman Bondi. In 2015, Robert Forward showed in a paper available here how negative masses can be used for propulsion without fuel. But as I explained in a recent essay here, we have no idea whether negative masses can be constructed in reality. In fact, their existence would create fundamental problems in our current understanding of the physical world. For example, negative masses can be used as building blocks in engineering a time machine which would violation causality, as I explained in an earlier essay here.
In principle, there are three types of mass:
1. Inertial mass, namely the mass given by the ratio between the force acting on an object and its resulting acceleration.
2. Active gravitational mass, namely the mass that generates the gravitational field around the object and affects the motion of other objects.
3. Passive gravitational mass, namely the mass that couples the object to the external gravitational field generated by other objects.
Momentum conservation requires that the active and passive gravitational masses would be equal. Otherwise, the momentum gained by one object will not necessarily be balanced by the momentum lost by another object when the two interact gravitationally with each other. Momentum conservation is a consequence of spatial translational symmetry, namely the invariance of the laws of physics to shifting a system from one position to another. Therefore, it is a sacred principle that cannot be violated.
The equality of the inertial mass and the passive gravitational mass is a fundamental assumption, called the Equivalence Principle, in Einstein’s theory of General Relativity. It rests on a pioneering experiment by Galileo Galilei at around 1590 and numerous follow-up experiments, which demonstrated that all objects accelerate the same way under the action of gravity irrespective of their mass or composition. In discussing negative mass objects, it is often assumed that conservation of momentum and the Equivalence Principle are both valid, and so all three forms of mass are the same.
However, the Equivalence-Principle rests on observational data for positive masses and could potentially be violated for negative masses. A new paper (available here) that I just co-authored with the brilliant PhD student, Oem Trivedi, shows that a system made of two objects which possess different values of the ratio between their gravitational and inertial masses would emit dipole gravitational radiation instead of the usual quadrupole gravitational radiation. The situation is analogous to a system made of positive and negative electric charges with positive inertial masses. So far, no sign of dipole gravitational radiation has been detected by the LIGO- Virgo-KAGRA (LVK) gravitational wave observatories. Current limits on dipole gravitational radiation are tight, as discussed here.
But even if the Universe contains only negative masses which satisfy the Equivalence Principle, binary systems containing such masses are expected to generate never-seen-before gravitational-wave signals:
1. Systems with a negative total mass are repulsive and short lived, preventing the formation of stable binaries.
2. Systems with a positive total mass, where the negative mass is smaller in magnitude than the positive mass, can form circular orbits. However, their evolution under gravitational radiation leads to expansion rather than inspiral, producing anti-chirp signals with decreasing frequency. Such a waveform is opposite to the chirp observed for all gravitational wave sources so far by LVK. The absence of anti-chirp signals in current gravitational wave catalogs provides a direct observational constraint on negative mass binaries. For an ordinary positive-positive binary, the orbital energy is negative and becomes more negative as the binary separation decreases, so gravitational-wave energy loss drives the system toward inspiral and increasing frequency. For a positive-negative binary with a positive total mass, the orbital energy starts being positive and decreases toward zero as the binary separation grows, so the same loss of gravitational-wave energy causes the system to expand rather than contract.
3. Systems with a zero total mass, where the negative mass cancels the positive mass precisely, correspond to runaway solutions where the pair accelerates up to the speed of light in some direction rather than engage in periodic motion.
So far, the new observational frontier of gravitational wave astrophysics did not lead to the discovery of new unexpected sources in our Universe over the past decade. This is somewhat disappointing and out of line with the history of astronomy, where observatories in a new band of the electromagnetic spectrum always revealed new unexpected sources. This was the case with radio telescopes discovering the cosmic microwave background, complex interstellar molecules or fast radio bursts; X-ray telescopes discovering accreting black holes, the cosmic X-ray background or X-ray clusters, and gamma-ray telescopes discovering gamma-ray bursts, gamma-ray pulsars or the cosmic gamma-ray background.
Our new paper shows that binary systems with negative mass members would generate gravitational-wave signals with never-seen-before properties. They provide novel targets for gravitational wave observatories which could either find them or rule them out.
ABOUT THE AUTHOR
(Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
Professional website:
https://lweb.cfa.harvard.edu/~loeb/
Social media:
https://avi-loeb.medium.com/
https://www.youtube.com/@ProfessorAviLoeb
https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd
https://x.com/ProfAviLoeb
View the full article
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By Avi Loeb Medium
The Mass of 3I/ATLAS is About a Billion Metric Tons, at Least a Hundred Thousand Times That of 1I/`Oumuamua
Observational data on the evolution of the mass loss rate of 3I/ATLAS dM/dt in various gasses: H2O (blue), OH (orange) and CO2 (green). The colored dashed-lines show various models for the mass loss rate. The solid pink and red curves display two preferred models to describe the combined total emission rate from water and carbon dioxide. The gray dotted line illustrates a previous model, favored in interpreting the rocket effect based on Hubble Space Telescope data (as reported here). (Image Credit: V. Thoss, A. Loeb and A. Burkert 2026)A new paper (accessible here) that I just co-authored with the brilliant Valentin Thoss and Andi Burkert from the University Observatory Munich, provides the best assessment to date of the mass of the mysterious interstellar object 3I/ATLAS.
As I discussed here on October 31, 2025, the rocket equation can be used to evaluate the non-gravitational force acting on 3I/ATLAS. The mass of 3I/ATLAS, M, times its non-gravitational acceleration, A, should be equal to the excess mass loss in a preferred direction, ζdM/dt, times the ejection velocity of the outflowing material, V,
M×A = (ζdM/dt) × V .
This provides a way to measure the mass 3I/ATLAS. By measuring the acceleration A and the mass-loss rate dM/dt and by modeling the velocity V, it is possible to derive the mass M of 3I/ATLAS for a reasonable value of the outflow asymmetry-parameter ζ ~0.5.
The new paper uses all available observational data on the evolution of the production rate of gas and dust and the brightening of 3I/ATLAS during the months surrounding its close approach to the Sun on October 29, 2025. The outgassing from the nucleus has led to a detectable non-gravitational acceleration. Our analysis combines models for the mass loss rate of water (H2O) and carbon dioxide (CO2) to derive the non-gravitational force and estimate the mass and size of 3I/ATLAS. In addition, we take into account a conservative constraint on the nucleus size from the active surface required for sublimation. If the mass loss is dominated by the sublimation of CO2, then the nucleus diameter is 0.84 kilometers, assuming a mass density of 0.5 grams per cubic centimeter and an asymmetry-parameter ζ ~0.5. Strong water sublimation of up to 10 metric tons per second from the surface is ruled out, as the required cometary surface area is incompatible with the rocket effect. A more conservative model of water production suggests a nucleus radius of 0.74 kilometer. In this case, a lower than usual cometary density or larger outgassing velocity could make the nucleus size estimate compatible with the lower bound of Hubble Space Telescope data of 2.6 (± 0.4) kilometers (as reported here).
Our analysis adopted three parameterizations: a purely CO2-driven sublimation which scales inversely with the square of the distance to the Sun, and two models accounting
for the contribution from water sublimation. These two models were fitted to the highest (model A) and lowest (model B) reported production rates, encompassing the range of uncertainty. By combining these models with data on the motion of 3I/ATLAS in the sky, we have estimated its mass and size. There is a subtle statistical preference towards the CO2 model with an inverse-square scaling, which becomes pronounced when we only include the data from large telescopes and interplanetary spacecraft. Despite systematic uncertainties, the magnitude of the non-gravitational acceleration can be estimated quite robustly.
The derived mass of 3I/ATLAS is (M/ζ)= 0.3 × 10^{12} kilograms for a CO2-only model, where ζ is the outgassing asymmetry factor. Including the contribution from water sublimation, we obtain (M/ζ)= 1.7 × 10^{12} kilograms and (M/ζ) = 6.4 × 10^{12} kilograms for the low and high limit of water sublimation from the nucleus. All in all, the mass of 3I/ATLAS is of order a billion metric tons!
Assuming a bulk density of 0.5 gram per cubic centimeter and ζ = 0.5, we estimate the diameter of 3I/ATLAS to be 0.84 kilometers for the CO2-driven sublimation, and 1.48 kilometers or 2.3 kilometers for the low (model B) or high (model A) limit of water sublimation.
Minimum radius (half-diameter) of the nucleus of 3I/ATLAS, required to sustain the observed production rate of gas with the entire surface being active. The solid lines correspond to various outgassing models and the dotted lines are the corresponding lower limits for the radius of 3I/ATLAS based on its non-gravitational acceleration. (Image Credit: V. Thoss, A. Loeb and A. Burkert 2026)We derive an additional constraint on the size of 3I/ATLAS by considering the surface required to sustain the sublimation. Under the most conservative assumptions, this leads to a strong tension for the model with high values of water production, requiring a diameter larger than 3 kilometers compared to the maximum value of 2.3 kilometers based on the corresponding non-gravitational acceleration. The high sublimation rate would therefore require a nucleus size that is too large to be compatible with the non-gravitational effect, even under extreme assumptions. This rules out model A and the corresponding mass and nucleus size, while the more conservative model B with lower levels of water production produces a mild tension, which could be alleviated by a lower bulk density or higher ejection velocity. This also implies that the sublimation of water (H2O) from the surface of 3I/ATLAS likely does not significantly exceed that from carbon dioxide (CO2). On the other hand, the bounds for a model which only includes CO2-sublimation is compatible with the non-gravitational estimates of the nucleus size.
The constraints from the active fraction suggest that the rocket effect of 3I/ATLAS might be dominated by CO2 sublimation throughout the orbit, with negligible contribution from water production. In this case the nucleus has an effective diameter of 0.8 kilometers, inconsistently with the Hubble data analysis that provided 2.6 (± 0.4) kilometers. Only if the production rates of CO2 have been underestimated by about an order of magnitude, could the two estimates be reconciled. If on the other hand water sublimation does contribute to the rocket effect of 3I/ATLAS, then the nucleus size would be larger. In this case, a lower than usual comet density together with larger gas velocities and collimation of the outflow could potentially push the estimated diameter as high as 2.2 kilometers, resolving the tension with the Hubble estimate and the required active fraction.
Additional data on the production rates of water and carbon dioxide would help to narrow down the range of possibilities and improve estimates of the mass and size of 3I/ATLAS.
But irrespective of the uncertainties, one conclusion is beyond any reasonable doubt: the third interstellar object 3I/ATLAS is at least 5 orders of magnitude more massive than the first interstellar object 1I/`Oumuamua — whose final mass was estimated to be of order 10⁷ kilograms here and here, assuming a natural origin for it as a hydrogen or a nitrogen iceberg without a visible cometary tail.
Based on the statistics of asteroids and comet nuclei of various sizes in the Solar System, we should have detected at least a hundred thousand 1I/`Oumuamua-mass objects before discovering a single interstellar object with the mass of 3I/ATLAS.
Does this discrepancy mean that one or both of these two mysterious interstellar objects is not natural in origin?
ABOUT THE AUTHOR
(Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
Professional website:
https://lweb.cfa.harvard.edu/~loeb/
Social media:
https://avi-loeb.medium.com/
https://www.youtube.com/@ProfessorAviLoeb
https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd
https://x.com/ProfAviLoeb
View the full article
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By Avi Loeb Medium
A Hubble Space Telescope image of 3I/ATLAS (Image Credit: NASA, ESA, STScI, D. Jewitt (UCLA), M.-T. Hui (Shanghai Astronomical Observatory))In a new paper (accessible here), I show that the recently inferred radius and interstellar number density of 3I/ATLAS-like objects, imply a local mass density that is larger by orders of magnitude than the available reservoir of heavy elements locked in low metallicity stars. This association was suggested by recent isotope abundance measurements. Either the inferred radius or number density are overestimated or the association with metal-poor stars is incorrect.
The interstellar object 3I/ATLAS offers new insights into the mass reservoir of planetary systems across the Milky-Way galaxy. The latest data from the Hubble Space Telescope (reported here), was used to derive a nucleus radius of R_n = 1.3 ± 0.2 km and an interstellar number density of n ∼ 7 × 10^{−3} au^{−3} (where au is the Earth-Sun separation).
For a typical nucleus density of ρ_n ≈ 0.5 g/cm^3, the inferred radius implies a nucleus mass of m_n ≈ (4π[R_n]^3ρ_n/3) = 4.6×10^{15} g. Hence, the local interstellar mass density of the population of 3I/ATLAS-like objects is,
ρ_{3I} ≈n×m_n =10^{−26} g/cm^3
Two recent papers (posted here and here) reported anomalous isotope abundances in the material that makes 3I/ATLAS. Based on JWST observations, Cordiner et al. (2026) had found
an isotope composition unlike any Solar System body. The water in 3I/ATLAS is enriched in deuterium at a level of D/H = (0.95 ± 0.06) percent, which is an order of magnitude higher than in known comets, suggesting a metal-poor origin. In addition, the 12C/13C isotope ratios (141–191 for CO2 and 123–172 for CO) exceeds typical values found in the Solar System, as well as in nearby proto-planetary disks. Chemical evolution models imply that the carbon isotopic composition originated 10–12 billion years ago. A similar conclusion was reached by Opitom et al. (2026), who reported measurements of carbon and nitrogen isotope ratios in 3I/ATLAS from observations of the cyanide (CN) molecule by the VLT. This data suggests a 12C/13C ratio of 147 (+87/−40) and a 14N/15N ratio of 343(+454/-124), more than twice above the value of ∼ 150 usually measured for Solar System comets.
Below, I show that a low-metallicity origin for 3I/ATLAS generates untenable tension with the inferred mass budget of the 3I/ATLAS population of interstellar objects.
The Galactic orbit of 3I/ATLAS suggest a likely origin in the disk of the Milky-Way galaxy. The composition of the coma of 3I/ATLAS in terms of carbon, oxygen and nitrogen — based molecules, implies that most of its mass is associated with heavy elements.
For reference, the Galactic mass density of stars in the neighborhood of the Sun is,
ρ_⋆ ≈ 0.04M_⊙ pc^{−3} = 2.7 × 10^{−24} g/cm^3
Only a tenth of all stars in the Milky-Ways disk have metallicities below a tenth of the solar value. Considering those metal-poor stars as the suggested source population of 3I/ATLAS and adopting their metal mass fraction to be ∼ 2 × 10−3, we find the corresponding local mass density of heavy elements in them to be,
ρ_z ≈2×10^{−3}×0.1×ρ_⋆ =5.4×10^{−28} g/cm^3
Since ρ_z ∼ 0.05ρ_{3I}, we conclude that the total mass density of heavy elements locked in low-metallicity stars is more than an order of magnitude below the required mass density in interstellar objects like 3I/ATLAS.
Planetary systems — which serve as the natural birth sites of interstellar objects — originate from debris disks that contain at least ten times less mass than the host star. In addition, one expects a mass spectrum of ejected inter- stellar objects to contain at least ten times more mass in objects with masses that are orders of magnitude different from that of 3I/ATLAS. When these additional factors are included, we find that low-metallicity stars miss the required mass budget by at least 3 orders of magnitude. They cannot account for the interstellar population of 3I/ATLAS-like objects unless they are capable of ejecting to interstellar space more than a thousand times the heavy-element content of their planetary disks.
In conclusion, either the inferred radius or number density of the population of 3I/ATLAS-like objects are overestimated or their association with metal-poor stars is incorrect.
ABOUT THE AUTHOR
(Image Credit: Chris Michel, National Academy of Sciences, 2023)Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
Professional website:
https://lweb.cfa.harvard.edu/~loeb/
Social media:
https://avi-loeb.medium.com/
https://www.youtube.com/@ProfessorAviLoeb
https://open.spotify.com/show/1zhndXkvSY2b8FdjspFpCd
https://x.com/ProfAviLoeb
View the full article
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