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Physicists on the CMS experiment announce the most elaborate mass measurement of a particle that is notoriously difficult to study and has captivated the physics community for decades.

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On balance, will AI help humanity or harm it? AI could revolutionize science, medicine, and technology, and deliver us a world of abundance and better health. Or it could be a disaster, leading to the downfall of democracy, or even our extinction. In Taming Silicon Valley, Gary Marcus, one of the most trusted voices in AI, explains that we still have a choice. And that the decisions we make now about AI will shape our next century. In this short but powerful manifesto, Marcus explains how Big Tech is taking advantage of us, how AI could make things much worse, and, most importantly, what we can do to safeguard our democracy, our society, and our future.

Marcus explains the potential—and potential risks—of AI in the clearest possible terms and how Big Tech has effectively captured policymakers. He begins by laying out what is lacking in current AI, what the greatest risks of AI are, and how Big Tech has been playing both the public and the government, before digging into why the U.S. government has thus far been ineffective at reining in Big Tech. He then offers real tools for readers, including eight suggestions for what a coherent AI policy should look like—from data rights to layered AI oversight to meaningful tax reform—and closes with how ordinary citizens can push for what is so desperately needed.

Taming Silicon Valley is both a primer on how AI has gotten to its problematic present state and a book of activism in the tradition of Abbie Hoffman’s Steal This Book and Thomas Paine’s Common Sense. It is a deeply important book for our perilous historical moment that every concerned citizen must read.

Gary Marcus is a leading voice in artificial intelligence, well known for his challenges to contemporary AI. He is a scientist and best-selling author and was founder and CEO of Geometric.AI, a machine learning company acquired by Uber. A Professor Emeritus at NYU, he is the author of five previous books, including the bestseller Guitar Zero, Kluge (one of The Economist’s eight best books on the brain and consciousness), and Rebooting AI: Building Artificial Intelligence We Can Trust (with Ernest Davis), one of Forbes’s seven must-read books on AI.

“Move fast and break things.” —Mark Zuckerberg, 2012

“We didn’t take a broad enough view of our responsibility.” —Mark Zuckerberg, speaking to the U.S. Senate, 2018

“Generative AI systems have proven themselves again and again to be indifferent to the difference between truth and bullshit. Generative models are, borrowing a phrase from the military, ‘frequently wrong, and never in doubt.’ The Star Trek computer could be counted on to gives sound answers to sensible questions; Generative AI is a crapshoot. Worse, it is right often enough to lull us into complacency, even as mistakes invariably slip through; hardly anyone treats it with the skepticism it deserves. Something with reliability of the Star Trek computer could be world-changing. What we have now is a mess, seductive but unreliable. And too few people are willing to admit that dirty truth.” —Gary Marcus

Shermer and Marcus discuss:

• The AI we have now and the AI we should want
• AI, AGI, Generative AI, ChatGPT
• What’s the problem to be solved?
• 12 biggest threats of Generative AI
• The morality of Silicon Valley
• How Silicon Valley manipulates public opinion
• How Silicon Valley manipulates government policy
• Data rights
• Privacy
• Transparency
• Liability
• Independent oversight
• Incentives good and bad
• Private vs. Government regulation of AI
• International AI governance.

If you enjoy the podcast, please show your support by making a $5 or $10 monthly donation.

Understanding the relationship between plasticity of muddy soil and earth pressure can be crucial to maintaining tunnel stability and predicting ground behavior during earth pressure balance (EPB) shield tunnelling, a common underground excavation method. Researchers developed small-scale model experimentation combined with moving particle simulation-based computer-aided engineering analysis that reliably predicted soil's plasticity and its correlating factors without having to deal with the cost and time of on-ground field analysis.

Watching for changes in Mars' orbit over time could be new way to detect passing dark matter, according to researchers.

A key step toward reusing CO2 to make sustainable fuels is chaining carbon atoms together, and an artificial photosynthesis system can bind two of them into hydrocarbons with field-leading performance.

Researchers developed an artificial motor at the supramolecular level that can develop impressive power. This wind-up motor is a tiny ribbon made of special molecules. When energy is applied, this ribbon aligns itself, moves like a small fin and can thus push objects. The energy for this comes from a chemical fuel.

Researchers developed an artificial motor at the supramolecular level that can develop impressive power. This wind-up motor is a tiny ribbon made of special molecules. When energy is applied, this ribbon aligns itself, moves like a small fin and can thus push objects. The energy for this comes from a chemical fuel.

With the help of NASA's Hubble Space Telescope, an international team of scientists has found more black holes in the early universe than has previously been reported. The new result can help scientists understand how supermassive black holes were created.

Cultural values and traditions differ across the globe, but large language models (LLMs), used in text-generating programs such as ChatGPT, have a tendency to reflect values from English-speaking and Protestant European countries. A research team believes there is an easy way to solve that problem.

In a new paper, physicists argue that close observations of merging black hole pairs may unveil information about potential new particles.

In a new paper, physicists argue that close observations of merging black hole pairs may unveil information about potential new particles.

Van Gogh's brushstrokes in 'The Starry Night' create an illusion of sky movement so convincing it led researchers to wonder how closely it aligns with the physics of real skies. Marine sciences and fluid dynamics specialists analyzed the painting to uncover what they call the hidden turbulence in the artwork. They used brushstrokes to examine the shape, energy, and scaling of atmospheric characteristics of the otherwise invisible atmosphere and used the relative brightness of the varying paint colors as a stand-in for the kinetic energy of physical movement.

Billions of dollars of observatory spacecraft orbit around Earth or in the same orbit as our planet. When something wears out or goes wrong, it would be good to be able to fix those missions “in situ”. So far, only the Hubble Space Telescope (HST) has enjoyed regular visits for servicing. What if we could work on other telescopes “on orbit”? Such “fixit” missions to other facilities are the subject of a new NASA paper investigating optimal orbits and trajectories for making service calls on telescopes far beyond Earth.

Some of the most productive orbiting telescopes operate at the Sun-Earth Lagrange points L1 and L2. Currently, those positions afford us some very incredible science. What they can’t afford is easy access for repairs and servicing. That limits the expected lifetime of facilities such as JWST to about 10-15 years. In the future, more missions will be deployed a Lagrange points. These include the Nancy Grace Roman Telescope, ESA’s PLATO and ARIEL missions, and the Large Ultraviolet Optical Infrared Surveyor (LUVOIR).

Artist’s impression of the Nancy Grace Roman Space Telescope, named after NASA’s first Chief of Astronomy. This spacecraft will orbit at SEL2, far from Earth. Credits: NASA

These observatories need propellants for attitude thrusters to help them stay ‘in place’ during their observations. There’s only so much “gas” you can send along with these observatories. In addition, components wear out, as they did with HST. So, people are looking at ways to extend their lifetimes through servicing missions. If failing components can be replaced and propellant delivered, the lifetimes of these observatories should be extended quite a bit, giving astronomers more bang for the observational buck.

Planning Future Spacecraft Servicing Missions

Researchers at the Satellite Servicing Capability Office (SSCO) at the Goddard Space Flight Center (GSFC) investigated the possibilities for servicing missions to distant space telescopes. In a recently released paper, they focus on the feasibility of on-orbit refueling missions for space telescopes orbiting at Sun-Earth Lagrange 2 (SEL2).

There are many challenges. For one thing, present-day launch technologies are (at this writing) inadequate to do that kind of mission at such distances. Clearly, the technology has to advance for servicing visits to take place. In addition, it’s important to remember that current telescopes, such as Gaia and JWST, weren’t designed for such access. However, future telescopes can be fitted with servicing ports, etc. to enable servicing. Finally, there are the challenges of actually getting the servicing missions to the observatories.

Illustration of OSAM-1 (bottom) grappling Landsat 7. This servicing mission concept was discontinued by NASA, but remains a good example of what’s needed to perform repairs and refueling to orbiting spacecraft. Credits: NASA

The Goddard team focused on this final issue by computing models of various launch and orbital solutions for such missions. Not only did they take into account the launch trajectories themselves, but also Sun-Earth-Lagrange point dynamics, plus the relative positions of observatories at SEL2. In addition, the team considered the stability of the observatories during and after rendezvous and attachment. All of these factors count when planning whether or not a servicing vehicle can be launched at a reasonable cost to extend the lifetime of the observatory enough to make the effort worth the time and expense.

Getting a Spacecraft Refuelling Mission Underway

The team created models for a theoretical mission for on-orbit fuelling at SEL2. That’s where JWST and Gaia are sitting, for example, along with WMAP, Planck, and others. The paper examines robotic refueling missions out to SEL2 for modeling purposes.

To do that, however, there must be an optimal trajectory for the robotic spacecraft to take out to SEL2. They need to be able to perform autonomous navigation to the correct point in space. Once at the target observatory, the refueling robot would then need to make a careful approach for its docking maneuvers. That requires on-orbit assessment of the target’s motion in space with respect to the Sun as well as its position in its SEL2 orbit. Docking itself can affect the observatory’s position and motion and the robot needs to take that into account, as well. The idea is to keep the observatory in the same position after docking.

However, the big question is: how do we get it out there inexpensively, fast, and safe?

The Goddard team primarily investigated the best and most efficient trajectories to get to SEL2. In particular, they looked at the best approaches to get to the Gaia spacecraft, which will run out of its propellant sometime in the next year. They also examined JWST as a possible target for such a mission. If such a mission was possible today, those observatories would gain years of “point and shoot” access to the Universe.

How to Get There

In their paper, the team looks at two approaches to the SEL2 refueling mission. One is a direct launch trajectory from Earth and the other is a spacecraft leaving from a geostationary transfer orbit (GTO). They assumed that the point of the mission was the fastest possible restoration of telescope operation. That dictates the shortest and safest possible trajectory along which the spacecraft can maintain constant thrust.

The Goddard team created a “forward design” approach for computing low-energy and low-thrust transfers from an Earth departure orbit to a space telescope orbiting the SEL2 point. Then they did the same for a servicing spacecraft leaving from a point in geostationary space. Essentially, either an Earth-departure or GTO-centric departure will work. Once the robotic servicing mission leaves Earth orbit, it travels at low thrust during a spiraling transit to SEL2. Once there, it does a rendezvous with the target, matches its motion in space, and then “locks on” to perform its delivery mission.

It’s important to remember that a launch from Earth or GTO is part of several solutions to SEL2 servicing missions. The team’s analysis resulted in a simplified process of generating possible orbits and trajectories for such activities. You can read the full text of their detailed analysis of the different trajectory solutions at the link below.

For More Information

Mission Design for Space Telescope Servicing at Sun-Earth L2
JWST Home Page
Gaia Telescope

The post There Could be a Way to Fix Spacecraft at L2, Like Webb and Gaia appeared first on Universe Today.

Maternity services need to educate parents-to-be on how pregnancy will affect their brain - their life could depend on it, says Helen Thomson

Echolocating bats can more easily find and pollinate long-stemmed flowers that stand out from the surrounding foliage, which may be why this floral trait evolved

Snoring is often viewed as harmless, at least to the snorer, but we are now uncovering its potentially serious effects on cardiovascular health. And finding ways to stop is surprisingly challenging

Given the spate of articles on antisemitism that Conor Friedersdorf publishes in the Atlantic, he would seem to be the house conservative (yes, defending Israel or criticizing campus antisemitism is now largely the purview of the right or of centrists). Indeed, Wikipedia says this about him:

In an interview with journalist Matt Lewis, Friedersdorf stated that he has right-leaning views but that he does not consider himself to be a doctrinal conservative or a member of the conservative movement.

I’m not sure, though, whether this is relevant when discussing his views, like those in the article below, as his arguments should stand on their own.  And I think that in the main they do, although perhaps the word “unethical” is a bit strong (I’d say “a violation of the right to a college education” or “campus protest encampment should be banned”). But you can decide for yourself by reading the piece. Click on the headline, or find the article archived here. (BTW, I’m going to try to find archived versions of articles that are paywalled, so look for “archived here” links in future posts.)

Indeed, Friedersdorf begins not by discussing ethical issues, but by arguing that campus encampments are maladaptive: the costs exceed the benefits. I’ve bolded the one place where he mentions ethics:

The practical, legal, and moral arguments against occupying the quad add up to a protest tactic with costs that far outweigh any benefits. Some of the problems with encampments are obvious, others subtle; taken together, they show that academic communities cannot thrive when any group uses coercion to try to force others to adopt its ideas––an approach that usually fails anyway. Activists should reject encampments as both unethical and ineffective.

Again, I’d say “ineffective and disruptive” rather than “unethical”. I can see where some could consider that activist notions that they have a right to disrupt the education of others is “unethical”, but if that’s the case, then any disruption in the cause of ideology is “unethical.” (Besides, it’s not at all clear that we’ll have any encampments this year.)

Now I know what you’re thinking: if encampments are unethical, why weren’t the disruptions of the Civil Rights movement in the Sixties—lunch counter sit-ins and so on—also unethical.  But there are several crucial differences between then and now, and I believe I’ve pointed them out before. But here they are again from Friedersdorf:

A standard defense of disruptive tactics is to invoke the civil-rights movement. Its leaders repeatedly engaged in civil disobedience––the knowing, willful violation of laws and rules to disrupt the status quo. If such “good trouble” played an integral part in a cause as righteous as the U.S. civil-rights movement, why are today’s encampments any different or less defensible? It’s a fair question to pose, but not a hard one to answer.

In the civil-rights-era victories, protesters were violating unjust laws, such as the ones that forced lunch counters to segregate. Today’s students are violating perfectly reasonable rules, such as the ones that forbid anyone, regardless of viewpoint, from erecting barricades to prevent fellow students from traversing the quad. Ending those illegitimate laws against segregated lunch counters made almost everyone better off. Ending legitimate rules against occupying the quad would make almost everyone worse off.

In addition, when “occupying” was a tactic in civil-rights-era civil disobedience, it was aimed at cogent targets. To protest segregation in a given jurisdiction, activists targeted segregated spaces in that jurisdiction.

Well, I suppose one could answer that divesting from Israel—the ultimate goal of encampments, which of course is completely futile—could be conceived as violating campus regulations in pursuit of a just cause.  After all, what’s really important vis-á-vis ethicality is the ultimate goal of your action, not which local regulations (short of proscribing violence) you violate to achieve it. Fortunately, for Friedersdorf (and unfortunately for the encampers), the immorality of colleges investing in Israeli companies (or even in funding through investments Israel’s war against Hamas) is not at all obvious.

There’s another difference, too, and one that Friedersdorf doesn’t mention. Civil rights protesters knew that they would be punished for their actions, and gladly accepted that punishment, even when it was severe, like being bashed by Southern cops, sprayed with water hoses, or jailed. The punishment was clearly part of the moral suasion that horrified onlookers. In contrast, today’s protesters and encampers regularly make it part of their list of “demands” that they not be punished for their actions. In other words, they insist on breaking the rules, but also insist on immunity to punishment.  That takes away from them the right to claim civil disobedience.

There’s no doubt that many, perhaps most, encampments are against college regulations and are disruptive. Ours certainly was, blocking access to campus and disrupting classes with noises, bullhorns, and megaphones.  These encampments are against most college regulations, but invertebrate administrators let them go up  anyway. In some cases, such as UCLA, the encampers even prevent “Zionist” students (i.e., Jews), from crossing the area or even entering class.  And that is not only disruptive, but against campus regulations.  Sadly, administrators, who are often weak and spineless, let this stuff happen under the misapprehension that it constitutes “free speech” (it might be in some situations; see below).

I found this story about UCLA interesting because the Jewish students filed suit against their school and won:

UCLA offers a case study in what’s wrong with encampments. Royce Quad is a space many students crisscross to access central parts of campus. On April 25, pro-Palestine protesters formed an encampment with barricades. Entrances were guarded by activists, many of them masked. They barred entry to students who support Israel’s existence. On April 30, an angry crowd gathered to protest the barricades and encampment. Counterprotesters “hid their faces behind masks and scarves,” CNN reported. “Some attackers sprayed protesters with chemical irritants, hit them with wooden boards, punched and kicked them and shot fireworks into the crowd of students and supporters huddled behind umbrellas and wooden planks, attempting to stay safe.” Authorities, who had failed to stop protesters from unlawfully occupying the quad, similarly did not intervene as counterprotesters unlawfully assaulted some of its occupiers.

Three Jewish students who were denied the ability to cross the quad filed a federal lawsuit against UCLA, arguing that they have a religious obligation to support a Jewish state in Israel, that their religious belief caused them to be denied equal access to their college education, and that UCLA nevertheless allowed the encampment to remain in place for a week. UCLA countered that it lawfully exercised the discretion that it needs when trying to avoid the escalation of conflicts.

The group Faculty for Justice in Palestine at UCLA submitted an amicus brief in the case, arguing that their allies are the ones who were mistreated. “Students and faculty of the Palestine Solidarity Encampment have been subjected to police brutality and mob attacks by self-proclaimed Zionists and white Supremacists, representing an almost total failure of UCLA to provide timely intervention or protection,” their brief asserts. In its telling, “Entrance to the encampment is contingent on principles, politics, and solidarity with the Palestinian struggle, and not on identity.”

Federal Judge Mark C. Scarsi disagreed. Earlier this month, he issued a preliminary injunction siding with the Jewish students, writing that they “were excluded from portions of the UCLA campus because they refused to denounce their faith.” He called this “abhorrent to our constitutional guarantee of religious freedom.” UCLA appealed the ruling, then dropped that appeal. The school is obligated to clear future encampments, or else to shut down any educational program––a class, lecture series, and so on—that is inaccessible to anyone due membership in a protected class.

Note that UCLA was on the side of the protestors!

I have to note, though, that even Friedersdorf isn’t down on all encampments, as he gives a pass to those that aren’t so disruptive:

Granted, it is possible to set up a peaceful encampment that is intended not to intimidate, but to raise awareness or show ongoing commitment to a cause. When visiting UC Berkeley one day last spring, I found the tents pitched in front of Sproul Plaza to be minimally disruptive, in a lively part of campus where free-speech activities are constant. The encampment was far from academic buildings, did not block pedestrian traffic, was easy to avoid by using other routes onto campus, and seemed easily monitored by UC police officers stationed nearby.

But nondisruptive encampments are the exception, not the rule, partly because crowds of young people behave unpredictably, and partly because disruption is often the point.

Does this mean that Friedersdorf considers encampments like the one at Berkeley to be “ethical”? Unless there are university regulations that allow encampments in some places but not in others, then they’re equally illegal.  But I guess to Friedersdorf, “ethicality” equates with “nondisruptive.”

I’m on the fence about this one, at least the “unethical” desription. Clearly, it’s illegal to blockade campuses in a disruptive way, and, after a warning, violators should be disciplined.  But for just a few tents in an out-of-the-way place that aren’t disruptive, I wouldn’t be so draconian.  That could, after all, be considered a demonstration of freedom of speech, and even if violations prohibit encampments, I wouldn’t necessarily enforce a small, unobtrusive one. But of course the very point of encampments is to be disruptive in a way that is supposed to force the university to divest (along with other demands).

About the “ethicality” trope, I am not sure I agree. But perhaps our difference is largely semantic. To me, “disruptive and illegal” would suffice.

h/t: Mayaan

Astronomers have observed three types of black holes in the Universe. Stellar-mass black holes formed from the collapse of a massive star, intermediate mass black holes found in some star clusters, and supermassive black holes that lurk in the centers of galaxies. But there is a fourth type that remains hypothetical an unobserved. Known as primordial black holes, they are thought to have formed from tiny fluctuations in the hot and dense early cosmos. Since they wouldn’t have formed from stars or mergers, they could have a much smaller mass. And with small masses, primordial black holes would be tiny. Their event horizons would be smaller than an apple, perhaps as small as a grain of sand. You can see why they would be hard to find.

If they exist, these dustmote singularities would be a perfect candidate for dark matter. This is not a new idea. Observations of dark matter have ruled out stellar-mass black holes and even planet-mass ones, but they haven’t quite ruled out primordial black holes. So they are a possible explanation for dark matter, but how would we prove it? A new study on the arXiv tries to find out.

Observational constraints on primordial black holes over various mass ranges. Credit: M. Cirelli (2016)

The authors begin by noting that if dark matter really is composed of primordial black holes, then they must be clustered around regular matter in the way dark matter does. There must be a halo of tiny black holes surrounding the Milky Way, and there must be primordial black holes scattered throughout our solar system. The gravitational pull of these tiny black holes should therefore affect the motion of planets, asteroids, and comets in detectable ways. Previous searches turned up nothing, but the authors wanted to know whether the effect would be significant enough to observe with our current technology.

So they ran several computer simulations to calculate the size of the effect. Since the gravitational pull of a single black hole would be tiny, the team looked at how nearby encounters would shift the orbits of solar system bodies. We describe orbital motion by ephemerides tables, so they used simulations to determine how the ephemerides would change over time. What they found was that even if we took a decade’s worth of ephemerides observations, the effect of primordial black holes would be an order of magnitude smaller than the limits of observation. In other words, even if primordial black holes exist their effect is way too tiny to observe in our solar system.

While the result is a bit disappointing, it does contradict a few studies that argue current observations rule out primordial black holes as dark matter. Though they are an unlikely solution to this cosmic mystery, they are still in the game.

Reference: Thoss, Valentin, and Andreas Burkert. “Primordial Black Holes in the Solar System.” arXiv preprint arXiv:2409.04518 (2024).

The post Could We Find Primordial Black Holes in the Solar System? appeared first on Universe Today.

Saturn is well known for its ring system and many recognise that the planets Jupiter, Uranus and Neptune also have rings. Did Earth ever have rings though? A team of researchers suggests that a worldwide collection of impact craters points to the existence of a ring around Earth millions of years ago. It’s possible that Earth captured and destroyed an asteroid that passed too close 466 million years ago. The asteroids torn up debris orbited the Earth as a ring and then the individual chunks entered the atmosphere, landed on the surface and produced the craters observed today. 

Seeing the rings of Saturn against an inky black sky are the very things that grabbed my attention as a ten year old boy. Since then I have been fascinated by all things space. The rings of Saturn, and Jupiter, Uranus and Neptune are made up of a collection of lumps of ice and rock all orbiting around the host planet in the same way our Moon orbits around the Earth. Collectively, and from a distance, they look like a complex system of rings. 

This NASA Hubble Space Telescope photo of Saturn reveals the planet’s cloud bands and a phenomenon called ring spokes. NASA, ESA, STScI, Amy Simon (NASA-GSFC)

The origin of the rings of the giant gas planets has been the cause of many debates over the decades. The most likely explanation is that the rings formed from the remains of moons or other celestial bodies that wondered a  little too close. The intense gravitational force from the planets tore the objects apart in a process known as tidal disruption. 

In a paper published by Andrew G. Tomkins and a team of researchers they suggest Earth too may have had its own rings in the past. Interactions between Earth and material from within our Solar System has been clearly evident. The Arizona crater and the Chicxulub impact event have left their scars on our planet but in the last 540 million years there was an increase in cratering events. Recorded in limestone deposits around the world are higher levels of chondrite (stony) meteorites and micrometeorite debris. At the same time there seems to have been an increase in seismic and tsunami activity although the correlation between the two is not confirmed. 

Barringer Crater, also known as Meteor Crater, in Arizona. This crater was formed around 50,000 years ago by the impact of a nickel-iron meteorite. Near the top of the image, the visitors center, complete with tour buses on the parking lot, provides a sense of scale. Credit: National Map Seamless Viewer/US Geological Service

The increase in meteoric material in limestone has been suggested as being caused by a general increase in asteroid dust across the inner Solar System but an interesting alternative theory has been suggested by Tomkins and his team. They propose instead that a large chondrite asteroid experienced a near-miss with Earth around 466 million years ago. If the object passed within the Roche limit of Earth, then Earth’s gravitational field will be strong enough to stop any smaller object from being held together by gravity. It would therefore break-up and lead to the formation of a debris ring.

The team investigated the impact sites of the 21 meteorite impacts known to coincide with the increase in meteorite activity in the Ordovician period. They then calculated the probability that the identified impact points resulted from randomly distributed impact events. This would be the likely cause of all the impactors came from the asteroid belt scenario. Instead the team concluded that the impact structure were located near to the equator as would be the case if they came from a single body that broke up in orbit. The resultant decay of the ring particles would have lasted several tens of millions of years before finally settling in the limestone records for future researchers to unearth. 

Source : Evidence suggesting that earth had a ring in the Ordovician

The post Earth Might Have Had Rings Half a Billion Years Ago appeared first on Universe Today.

In 2022, physicists were excited by hints that something was wrong with our understanding of the universe - but new results have put that in doubt