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Secrets of the Van Allen belt revealed in new study

Space and time from Science Daily Feed - Thu, 03/21/2024 - 12:54pm
A challenge to space scientists to better understand our hazardous near-Earth space environment has been set in a new study.
Categories: Science

N-channel diamond field-effect transistor

Matter and energy from Science Daily Feed - Thu, 03/21/2024 - 12:53pm
A research team has developed an n-channel diamond MOSFET (metal-oxide-semiconductor field-effect transistor). The developed n-channel diamond MOSFET provides a key step toward CMOS (complementary metal-oxide-semiconductor: one of the most popular technologies in the computer chip) integrated circuits for harsh-environment- applications as well as the development of diamond power electronics.
Categories: Science

N-channel diamond field-effect transistor

Computers and Math from Science Daily Feed - Thu, 03/21/2024 - 12:53pm
A research team has developed an n-channel diamond MOSFET (metal-oxide-semiconductor field-effect transistor). The developed n-channel diamond MOSFET provides a key step toward CMOS (complementary metal-oxide-semiconductor: one of the most popular technologies in the computer chip) integrated circuits for harsh-environment- applications as well as the development of diamond power electronics.
Categories: Science

New reactor could save millions when making ingredients for plastics and rubber from natural gas

Matter and energy from Science Daily Feed - Thu, 03/21/2024 - 12:53pm
A new way to make an important ingredient for plastics, adhesives, carpet fibers, household cleaners and more from natural gas could reduce manufacturing costs in a post-petroleum economy by millions of dollars, thanks to a new chemical reactor.
Categories: Science

In-situ observation of nanoscale heat propagation

Matter and energy from Science Daily Feed - Thu, 03/21/2024 - 12:47pm
A research team has developed a technique that enables the nanoscale observation of heat propagation paths and behavior within material specimens. This was achieved using a scanning transmission electron microscope (STEM) capable of emitting a pulsed electron beam and a nanosized thermocouple -- a high-precision temperature measurement device.
Categories: Science

SpaceX’s Starship created a volcano-like explosion in first launch

New Scientist Feed - Thu, 03/21/2024 - 12:00pm
The Starship rocket destroyed its launch pad during its first launch attempt in 2023, and the explosion resembled a powerful volcanic eruption, spraying sand and chunks of debris over a huge area
Categories: Science

Organic farms seem to trigger more pesticide use on conventional farms

New Scientist Feed - Thu, 03/21/2024 - 11:00am
Insects tend to be more abundant on organic farms than conventional ones, which may cause the pests to spill over into neighbouring fields, prompting these farmers to increase their pesticide use
Categories: Science

Pig kidney transplanted into living human for the first time

New Scientist Feed - Thu, 03/21/2024 - 10:48am
A genetically modified pig kidney has been successfully transplanted into a living human – and the recipient is expected to leave hospital soon
Categories: Science

Sulphur dioxide from Iceland volcano eruption has reached the UK

New Scientist Feed - Thu, 03/21/2024 - 10:38am
A huge plume of sulphur dioxide from the latest eruption in Iceland is drifting across Europe, but it isn't expected to cause any significant harm
Categories: Science

Speaking of Kalven and ideological neutrality. . .

Why Evolution is True Feed - Thu, 03/21/2024 - 10:20am

John K. Wilson is identified in the new article below in the Chronicle of Higher Education (CHI) as “the author of eight books, including Patriotic Correctness: Academic Freedom and Its Enemies and the forthcoming The Attack on Academia.”  In the piece below (access by clicking the headline), Wilson says that the concept of “official” academic neutrality, as embodied in the University of Chicago’s 1967 Kalven Report, has been misconstrued and misapplied.

Here are Wilson’s two beefs about Kalven (his words are indented):

1.)  The Kalven Report was a 1967 product of the University of Chicago faculty, yet is adjudicated not by the faculty but by the university administration (Wilson’s words are indented):

The Kalven Report is a monument to faculty power. It was the product of a faculty committee, decreeing restraints on the administration purely in order to protect faculty freedoms. And faculty members were given the sole power to interpret these limits. The Kalven Report noted that “the application of principle to an individual case will not be easy”; it called for “faculty or students or administration to question, through existing channels such as the committee of the council or the council, whether in light of these principles the university in particular circumstances is playing its proper role.” In other words, the administration (like everyone else) is required to go to a faculty committee for any question about how to interpret the Kalven Report. (Unfortunately, the University of Chicago administration has been violating the Kalven Report for decades by imposing its own interpretations of neutrality without faculty consultation.)

2.)  Wilson argues that the Kalven Report was meant to apply only to pronouncements by the University administration, not by University moieties like departments or Institutes:

The Kalven Report should also be followed for its approach to what institutional neutrality means, by limiting the term to actions and speech by top administrators on behalf of the entire college. The most dangerous betrayal of the Kalven Report’s principles is the extension of neutrality beyond the central administration to include all sub-units and faculty departments of a college.

Wilson is wrong—dead wrong—on both of these points, and was corrected by my Chicago colleague Brian Leiter (a law professor) in a letter to the CHE that came out just a few hours ago. Click below to read it:

From the letter:

Although John K. Wilson links to the actual text of the Kalven Report, he mischaracterizes it throughout his piece while alleging, ironically, that others “misunderstand” it (“More Colleges Are Swearing Off Political Positions. They’re Getting It Wrong”, The Chronicle Review, March 18). He declares that “shared-governance…is an essential part of the Kalven Report,” although it is not mentioned and has nothing to do with the principles articulated in that document. He says falsely that “the University of Chicago administration has been violating the Kalven Report for decades by imposing its own interpretations of neutrality without faculty consultation,” even though the Report requires no such consultation and even though, in the most recent cases, it was precisely faculty (including myself) who raised Kalven violations with the university, prompting it to act.

and

President Zimmer’s clarification made explicit longstanding understandings of Kalven’s principles; after all, as the report emphasizes, “The instrument of dissent and criticism is the individual faculty member or the individual student,” not the university or department or school. Kalven cautions that we “cannot resort to majority vote to reach positions on public issues,” which is exactly what many departments started doing in the wake of George Floyd’s murder. Department orthodoxy is, arguably, far more dangerous than university orthodoxy: An untenured faculty member might perhaps ignore the provost’s pronouncements about “systemic racism” but be more wary when her own department issues a statement of an official position.

Brian doesn’t pull any punches, and implicitly accuses Wilson of “lying” (yes, the word is used) about Kalven.

Leiter has also put a note about this on his own website, the Leiter Reports: A Philosophy Blog. Click to read:

Two bits from the blog (I’ve omitted Brian’s excerpt from the CHI letter):

Years ago, I was impressed that Mr. Wilson (a freelance “academic freedom” expert [sic] as it were) was one of the few who spoke up on behalf of the attack on the free speech rights of Ward Churchill.  Alas, it’s now clear that his interest in free speech and academic freeodm is partisan through and through, as his astonishingly dishonest attack on the University of Chicago’s Kalven Report makes clear.

. . . Mr. Wilson is not as egregious an enemy of academic freedom as Jennifer Ruth or Michael Berube, but he is not an honest broker.  (I have corresponded with Mr. Wilson about other academic freedom issues, after being e-introduced to him by Nadine Strossen, and my impression from that is that he was not very smart and not really interested in a principled conception of academic freedom.  This latest incident confirms my impression then.)

As you see, no punches are pulled here, either. I’ve worked with Brian on Kalven, and although he can be brusque, he’s also efficient, eloquent, and, by Ceiling Cat, gets things done!  Kalven has and is being enforced, and, by and large, it’s worked quite well here. While schools like Harvard, MIT, and Penn get in big trouble by lacking any academic neutrality and unevenly enforcing what speech policy they do have, the University of Chicago hasn’t been hauled before Congress, excoriated in the press, or lost any donors.

Categories: Science

China’s Next Lunar Relay Satellite Blasts Off

Universe Today Feed - Thu, 03/21/2024 - 10:08am

Communication between spacecraft relies upon line of site technology, if anything is in the way, communication isn’t possible. Exploration of the far side of the Moon is a great example where future explorers would be unable to communicate directly with Earth.  The only way around this is to use relay satellites and the Chinese Space Agency is on the case. The first Queqiao-1 was able to co-ordinate communications with Chang’e-4 landers and now they are sending Queqiao-2 to support the Change’e-6 mission. 

If you have ever gazed upon the Moon you might have noticed that it always has the same hemisphere facing the Earth. This phenomenon is known as captured or synchronous rotation. It may look like the Moon isn’t rotating but in reality the time it takes to spin once on its axis is the same as the time it takes to complete one orbit around the Earth, keeping one hemisphere constantly facing us. Explorers on the near side of the Moon have no trouble communicating with transmissions taking just over one second to reach home. Explore the far side of the Moon and you have a problem. 

The Chang’e 5 test vehicle captured this beautiful view of Earth over the far side of the Moon on October 28, 2014. Credit: Chinese national space agency (CNSA) and Chinese Academy of Sciences (CAS)

To overcome the problem China have launched a 1.2 ton communication satellite known as Queqiao-2. It’s name originates from the mythological bridge made from magpies. In the Chinese tale, the magpies formed a bridge across the Milky Way to allow the lovers Vega and Altair to be together for one night once a year. Two miniature satellites were also launched Tiandu-1 and Tiandu-2 from the island of Hainan.

On arrival it will orbit the Moon and provide a relay for the Chang’e-6 lander which is slated to launch in May.  It will join satellites from United States, India and Japan to support the exploration of the far side of the Moon. Chang’e-6 will collected samples from an ancient basin. Not only will it serve the communications for Change-6, it will transfer communications for Chang’e-7 and ‘8. Both craft are to be launched in the years ahead 2026 and 2028 respectively. 

The orbit of Queqiao-2 will take it almost over the south pole in an elliptical orbit. It will reach an altitude of 8,600 km so that communication can be achieved for a little over eight hours. At its closest, it will sweep over the lunar surface at an altitude of 300 km.

The ultimate goal of the Chinese Space Agency is to create a network of satellites, not too dissimilar (but not quite on the same scale) to the growing Space X constellation which is building a global internet presence. The purpose of Tiandu-1 and Tiandu-2 is to test the concept of such a constellation. 

China’s longer term aspirations include a research station at the lunar south pole and for this to be viable, communication relays are essential to establish communication, navigation and remote sensing. 

Source : China launches signal relay satellite for mission to moon’s hidden side

The post China’s Next Lunar Relay Satellite Blasts Off appeared first on Universe Today.

Categories: Science

Teen sweat has distinct chemical make-up with notes of musk and urine

New Scientist Feed - Thu, 03/21/2024 - 9:00am
Teenagers and babies produce different chemicals in their sweat, which may be why infants are generally considered to smell sweeter
Categories: Science

Food costs more because of climate change - and it will get worse

New Scientist Feed - Thu, 03/21/2024 - 9:00am
Rising temperatures are predicted to drive up food inflation by between 0.9 and 3.2 per cent a year by 2035, as crop yields suffer from extreme heat
Categories: Science

NASA Experiments Planned for the April 8th Total Solar Eclipse

Universe Today Feed - Thu, 03/21/2024 - 8:48am

Totality and the April 8th total solar eclipse offers a rare chance to study the Sun.

We’re less than three weeks out now, until the April 8th total solar eclipse crosses North America. And while over 31 million residents live in the path of totality, many more will make the journey to briefly stand in the shadow of the Moon. Several scientific projects are also underway to take advantage of the event.

The eclipse traverses Mexico, the United States from Texas to Maine, and the Canadian Maritime provinces before heading out over the Atlantic. Maximum totality for this eclipse in 4 minutes and 27 seconds, longer than the 2017 total solar eclipse. This is the only total solar eclipse worldwide for 2024, and the final total solar eclipse for a generation for the contiguous United States until 2044.

A Brief History of Total Solar Eclipse Science

Eclipses have always offered astronomers a chance to carry out rare observations. The element helium (named after ‘Helios’ the Greek god of the Sun) was discovered in the solar chromosphere during the August 18th, 1868 total solar eclipse. Astronomers swept the sky near the eclipsed Sun in July 29th, 1878, looking for the hypothetical planet Vulcan. World War I thwarted astronomer’s plans to test Einstein’s Theory of General Relativity during the August 21st, 1914 eclipse. This had to wait until Arthur Eddington led an expedition to Principe in 1919. Eddington vindicated Einstein with measurements of the deflection of stars observed near the Sun during totality.

Stranger experiments continued right up into the 20th century. One of the more bizarre eclipse experiments was hunting for the elusive ‘Allais Effect,’ looking for the deflection of a pendulum during totality. Alas, Maurice Allais’ findings alluding to this fringe idea have never been replicated. Maybe LIGO Livingston just outside the path of totality on 2024 could take up the challenge?

Four Eclipse Science Projects

In 2023, NASA selected four major experiments to chase totality:

1. The Solar Patrol sunspot campaign: This effort is led by Thangasamy Velusamy out of NASA’s Jet Propulsion Laboratory. This initiative seeks to monitor subtle changes in the magnetic fields of active sunspot regions as the Moon passes over them. The team will use the 34-meter Goldstone Apple Valley Radio Telescope based in California (outside of the path of totality) to carry out this experiment. We’re headed towards the peak of Solar Cycle 25 over the coming year, so the odds are pretty good that the Sun will be dappled with multiple sunspots, come eclipse day.

2. SuperDARN to probe the ionosphere: Led by Bharat Kunduri out of Virginia Polytechnic Institute and State University, this experiment seeks to measure how the upper ionosphere reacts to the eclipse. Crucially, totality passes over three SuperDARN (Super Dual Auroral Radar Network) sites during the eclipse, offering an unprecedented opportunity.

3. Pro/AM ‘Listening Party’ to observe QSOs: Ham radio operators are familiar with the enhanced nighttime reflectivity of the upper ionosphere. This effect allows for reception of distant stations that are otherwise silent in the daytime. This sort of contact is known as a ‘QSO’ in ham radio-speak, and it also occurs during an eclipse, as totality briefly mimics the approach of night. Nathaniel Frissell of the University of Scranton is leading an effort to make QSO contacts on April 8th. A good strategy is to pick an AM station a few hundred miles distant and listen before, during and after totality passes. Even today, most cars still come equipped with AM/FM radios. This is also an experiment that can be done from outside of the path of totality.

A modified, eclipse-chasing WB-57 aircraft is towed out for a mission. NASA Chasing the Shadow

4. NASA’s WB-57 missions to take flight once again. The most ambitious endeavor is once again underway, as NASA’s two converted WB-57 Canberra aircraft will once again chase the shadow of the Moon. NASA owns the last three Canberra aircraft still in service. Two of these aircraft will fly out of Ellington Field outside of Houston, Texas on eclipse day. The jet aircraft will intercept the Moon’s shadow, which will be moving at over 2,500 miles per hour. This allows for an extra two minutes of totality. Both aircraft will carry a suite of cameras and spectrometers, allowing astronomers to analyze the inner corona very near the Sun. Studying the region could go a long ways towards solving the ‘coronal heating problem,’ a mystery evolving why the corona is exponentially hotter than the photosphere of the Sun.

Images of the Sun from GOES-16, versus the Sun during eclipse (far right) showing loops in the lower corona. NASA

Observations from the 2017 eclipse hinted that oscillations in the lower corona may feed ‘nano-flares’ that pump energy into the outer corona. This time, two new observatories will be on hand to back up NASA’s eclipse measurements. These are the European Space Agency’s Solar Observatory (SolO) and NASA’s Parker Solar Observatory.

The flight will also continue the campaign to scan the sky near the eclipsed Sun to hunt for elusive Vulcanoid asteroids interior to the orbit of Mercury. General Relativity did away with the need to evoke an inter-Mercurial world to explain the anomalous precession of Mercury’s orbit. The jury is still out, however, on whether smaller asteroids could still exist near the Sun. MESSENGER scoured the region near the Sun en route to Mercury. NASA will once again look for Vulcanoids as a secondary objective during the 2024 eclipse.

NASA has also chased eclipses aloft using Gulfstream III aircraft:

More Total Solar Eclipse Science

Other citizen-science projects are also planned for April 8th. One intriguing project is the Citizen Continental-America Telescope Eclipse network, known as Citizen CATE. This project sees volunteers setup along the total solar eclipse path, with the objective of augmenting corona observations.

An animation of the corona in polarized light, as seen during the 2017 total solar eclipse. NASA/Gopalswamy et al.

I have a deep respect for all those who are devoting precious time during totality to eclipse science. Perhaps, you’ll simply be happy will clear skies to enjoy the view. If you haven’t got your eclipse glasses yet to safely obverse the Sun, Astronomy For Equity still has ‘em available. Hey, they’re for a good cause…

Good luck and clear skies to all who are headed into the shadow of the Moon on eclipse day, whether its for the cause of science, or just to enjoy the view.

The post NASA Experiments Planned for the April 8th Total Solar Eclipse appeared first on Universe Today.

Categories: Science

In what ways should scientific organizations remain politically neutral?

Why Evolution is True Feed - Thu, 03/21/2024 - 8:45am

Agustín Fuentes is surely bucking for Social Justice Scientist of the Year, as I’ve documented in numerous posts. Whenever there’s an article about how scientists are bigoted, racist, and sexist, including Darwin, or there’s an article to be written that extols social justice in science but will have little or no effect on society, you’re likely to find Fuentes’s name on it. (He’s a professor of anthropology at Princeton.)

In his latest attempt to introduce politics into science, he’s written an “eLetter” to Science that you can read by clicking on the headline below. I didn’t know of eLetters before, but they’re constitute “a forum for ongoing peer review. eLetters are not edited, proofread, or indexed, but they are screened.”  Perhaps I should have submitted this as an eLetter instead of posting it here, but I’ve already started writing it, so let’s proceed.

In this eLetter Fuentes argues at great length that scientific journals and organizations should use their expertise to pronounce on political, social, and moral issues of the day. In other words, these organizations should not be institutionally neutral, as the University of Chicago is (see our Kalven Report).  But I think he’s dead wrong and that these institutions should strive to be neutral except when pronouncing on political issues that directly affect the science or branch of science that an organization represents. The reasons, of course, are the same ones that created our Kalven Report: official pronouncements on debatable issues tend to chill speech, they require someone to be the arbiter of what is the “right” view, and are often likely to be deeply conditioned by an ideology that’s transitory. This is the problem with many pronouncements on racial and gender disparities in the past; our views have become more moral and egalitarian, as well as more informed by data; and this will continue.

Well, read Fuentes’s view on how organizations should be making the “right” statements about society, and of course Fuentes is the arbiter of what is “right”:

Here are three statements that, says Fuentes, are ones that scientific organizations have made and should have made because they are scientifically true. (His words are indented except when noted otherwise). Only the first lacks obvious social import.

The following are three incontrovertible statements of scientific fact:

“Biological evolution is the central organizing principle of modern biology.”

Genetics demonstrates that humans cannot be divided into biologically distinct subcategories.”

“While ‘race’ is not biology, racism does affect our biology, especially our health and well-being.”

While the first statement seems true, it is still debatable, and I have in fact seen scientists take issue with it. I would simply say that “evolution” is the explanation for how things got the way they are, and that the alternative of creationism is false. The sentence “nothing in biology makes sense except in the light of evolution”, a famous pronouncement by my scientific grandfather Theodosius Dobzhansky, is ambiguous unless you carefully explain what “making sense” and “in the light of evolution” means. But I am less concerned with this than with the other statements.

The second statement is true in one sense, in that we cannot divide humanity into a finite and agreed-upon number of populations with big genetic differences, but in fact “race” is not a social construct, either. There’s biology behind it, even in the “crude” races that most of us can name.  If it were a purely social construct, companies like 23andMe wouldn’t work, and you couldn’t tell someone’s ancestry with a high degree of accuracy using multiple loci or even morphology.  Here’s a bit that Luana Maroja and I wrote on race in our Skeptical Inquirer paper dealing with the erosion of biology by ideology.

Even the old and outmoded view of race is not devoid of biological meaning. A group of researchers compared a broad sample of genes in over 3,600 individuals who self-identified as either African American, white, East Asian, or Hispanic. DNA analysis showed that these groups fell into genetic clusters, and there was a 99.84 percent match between which cluster someone fell into and their self-designated racial classification. This surely shows that even the old concept of race is not “without biological meaning.” But that’s not surprising because, given restricted movement in the past, human populations evolved largely in geographic isolation from one another—apart from “Hispanic,” a recently admixed population never considered a race. As any evolutionary biologist knows, geographically isolated populations become genetically differentiated over time, and this is why we can use genes to make good guesses about where populations come from.

More recent work, taking advantage of our ability to easily sequence whole genomes, confirms a high concordance between self-identified race and genetic groupings. One study of twenty-three ethnic groups found that they fell into seven broad “race/ethnicity” clusters, each associated with a different area of the world. On a finer scale, genetic analysis of Europeans show that, remarkably, a map of their genetic constitutions coincides almost perfectly with the map of Europe itself. In fact, the DNA of most Europeans can narrow down their birthplace to within roughly 500 miles.

Of what use are such ethnicity clusters? Let’s begin with something many people are familiar with: the ability to deduce one’s personal ancestry from their genes. If there were no differences between populations, this task would be impossible, and “ancestry companies” such as 23andMe wouldn’t exist. But you don’t even need DNA sequences to predict ethnicities quite accurately. Physical traits can sometimes do the job: AI programs can, for instance, predict self-reported race quite accurately from just X-ray scans of the chest.

As for the third statement, it’s totally debatable. Yes, the idea that “racism affects some people’s biology” is trivially true. But statements like “racism is responsible for the higher mortality of  black than of white both mothers and babies in America” (something widely touted in the press) assigns a debatable cause to an undisputed fact. Yes, that difference exists, but there are other explanations as well, including cultural and dietary differences, physiological conditions like liver disease and blood pressure, drug use, and so on, and nobody has bothered to even mention these alternatives in the literature. Taking the default explanation as “ongoing racism” for a phenomenon with several possible explanations is not good science. Fuentes’s third statement is debatable and can’t be taken as prima facie true. It is potentially resolvable by science, but it has not been resolved.

Because of default explanations involving ongoing and structural racism or sexism have now become pervasive in official pronouncements of scientific journals and societies—and not just about society but about internecine matters like promotions, grants, and acceptance of papers—we should be wary of statements like the following, also coming from Fuentes:

As part of this cultural shift over the past 5 years, a range of scientific organizations that focus on human biology, psychology, and health have released powerful, scientifically grounded statements against the misuse, misperception, and misrepresentation of data and analyses on human variation. These include clarifications on why and how races are not biological divisions of humanity, what human genetic diversity looks like, how racism shapes and affects human health, why IQ and economics are not best understood through aspects of one’s biology, and how disease patterns relate to human biological and social diversity. Many of these organizations have also produced critiques of their own historical and core roles in propagating bias, bad scientific practice, and harms, such as eugenics, discriminatory medical and psychological treatment, and miscegenation laws. Such statements have been released by the US National Academies of Sciences, Engineering and Medicine; the American Medical Association; the American Psychological Association; and American Association for the Advancement of Science (AAAS, the publisher of Science).

But, as Luana and I showed, scientific organizations are still propagating bias, misconceptions, and misunderstanding by trying to hew to a “progressive” ideological agenda.  The sword of non-neutrality cuts both ways.

True, many of the statements to which Fuentes refers are “scientifically grounded” in that they invoke science and sound scientific, but they’re often based on assumptions that have not been scientifically tested. In other words, they’re debatable, and that means that promoting them as if they’re “incontrovertibly true” is wrong.

Here’s what Fuentes thinks we’re doing wrong: being politically neutral:

There are, however, individual scientists, politicians, and members of the public who decry public statements by scientific organizations as “political,” asserting that the only reason they weigh in on societal issues is because of partisan pressures. Their core argument is that science should be neutral and forays into the political realm damage scientific integrity. It is true that some organizations’ statements endorsing political candidates or particular human rights stances are intentionally political and not exclusively tied to the organizations’ focal areas. In such cases, the organizations should be extremely careful and fully consider the impact, negative and positive, on their standing and credibility. Simply put, not all organizations should weigh in on all, or even most, societal topics. But it is also true that science as a field of practice, and scientific organizations as entities, have never been neutral.

Of course scientists have never been completely neutral on political, ideological, or moral issues, but that doesn’t mean they shouldn’t try to be neutral.  And that means avoiding making political, ideological, or moral pronouncements that don’t affect the progress of science (or of the branch of science promoted by a journal or society).  If there are important social issues whose outcome depend critically on science, then perhaps scientists can weigh in, but the science has to be nearly irrefutable, and people have to be careful. Far better to comment as a “private citizen” scientist (even writing op-eds like Fuentes’s, properly labeled as “personal opinions”) than for scientific organizations and journals to make official statements.

Equally important, although Fuentes pronounces early on that “science, as a human undertaking, cannot be neutral,” he’s wrong. Science is a set of tools to find out truths about the world: observation, experiment, replication, hypothesis-making and -testing, doubt, double-blind tests, and so on.  It is scientists who break neutrality, not science itself. Just because science is a human endeavor doesn’t give us license to go around making official statements about human society. Of course scientists are free, like all Americans, to give their personal views, so long as it doesn’t involve harassment, false advertising, or defamation.

If you want some examples of where this non-neutrality goes wrong, Fuentes supplies them, though inadvertently:

Case in point: As of March 2024 there are there are more than 490 legislative bills in consideration in 41 states seeking to criminalize the use of public restrooms that match one’s identified gender for some individuals, limit or deny access to gender-affirming care, and a range of other legal restrictions targeting transgender and nonbinary youth and adults. These legislative actions fly in the face of contemporary scientific understandings and the recommendations from the major medical professional organizations, including the US National Institutes of Health. At their heart, the bills have little to do with evidence-based research, science, or data, relying on decidedly unscientific contentions to support their agendas. Recently, seven professional scientific organizations that focus on human biology, human evolution, and human genetics released a joint statement in support of trans lives, including transgender, nonbinary, gender and sex diverse, and queer communities. The statement affirms the power of all persons to make the ultimate decisions over what happens to their own bodies, and based on contemporary scientific understandings opposes legislation rooted in biological essentialism affecting reproductive justice and access to health care, especially the discrimination and denial of health care for youth and adults, including care that is gender and life affirming. Although this is a small act, the reaction that it stimulated, and the likelihood of more professional science organizations acting as well, such as the American Psychological Association’s recent statement, illustrate that such organizations can, and should, effectively contribute to critical societal issues. Scientific data and analyses matter, even when their public presentation can be considered “political.”

Seriously? What can science tell us about restroom use? That is a social problem that is at best minimally informed about science, and science journals and organizations best stay well away from it. In fact, the “science” of gender-affirming care also consists largely of subjective evaluations or statements lacking evidence, and, at least in the U.S., scientists appear to have gotten it largely wrong. We don’t know the long term effects of puberty blockers, and perhaps objective rather than “affirming” therapy could kids from surgery, allowing them to become gay instead of snipping of their parts. There is very little good science behind “affirmative care.” And there is no science supporting the gender-activist issue (one supported no doubt by Fuentes) that transwomen should be allowed to compete in athletics against biological women. The science in fact says exactly the opposite: transwomen retain, perhaps for life, substantial athletic advantages over natal women. Has that stopped scientists from arguing that “transwomen are women” in every relevant sense? Nope.

To support the view that “affirmative care” isn’t supported by science, observe that countries in Europe, but not the U.S., are doing away with a lot of gender-affirming care, including deeming puberty blockers as clinical rather than normal treatments.  That’s because the science is unsettled! It is clear what Fuentes’s agenda is here, and it’s pure, unsullied gender activism, which at present rests largely on scientifically unsupported claims. Fuentes is touting ideology here, not the weight of scientific evidence.

Which brings me to my final point. Science not only gets political and ideological pronouncements wrong, but often gets the science itself wrong—and gets it wrong because the “science” touted by activists is distorted to reflect ideology. Luana and I wrote about five such areas in our paper, including “race” differences, gender differences, evolutionary psychology, and indigenous “knowledge.” If journals and societies can get the very science wrong because they are blinkered by ideology, what hope do we have for getting political or ideological issues right?

h/t: Luana

Categories: Science

Why 2024 Abel prize winner Michel Talagrand became a mathematician

New Scientist Feed - Thu, 03/21/2024 - 8:17am
After losing an eye at the age of 5, the 2024 Abel prize winner Michel Talagrand found comfort in mathematics
Categories: Science

Has Neuralink made a breakthrough in brain implant technology?

New Scientist Feed - Thu, 03/21/2024 - 6:14am
Elon Musk's brain-computer interface firm Neuralink has released a video of its first patient, Noland Arbaugh, controlling a computer cursor with his thoughts - is this the future?
Categories: Science

Fluffy beetle discovered in Australia may be the world's hairiest

New Scientist Feed - Thu, 03/21/2024 - 6:02am
The exceptionally long white hairs on the newly named longhorn beetle Excastra albopilosa may deceive predators into thinking it’s covered in fungus
Categories: Science

The Mars Science Helicopter Could be an Airborne Geologist on Mars

Universe Today Feed - Thu, 03/21/2024 - 5:42am

After over 70 successful flights, a broken rotor ended the remarkable and groundbreaking Ingenuity helicopter mission on Mars. Now, NASA is considering how a larger, more capable helicopter could be an airborne geologist on the Red Planet. For the past several years scientists and engineers have been working on the concept, proposing a six-rotor hexacopter that would be about the size of the Perseverance rover.

Called the Mars Science Helicopter (MSH), it would not only serve as an aerial scout for a future rover, but more importantly, it could also carry up to 5 kg (11 lbs) of science instruments aloft in the thin Martian atmosphere and land in terrain that a rover can’t reach.

A new paper presented at the March 2024 Lunar and Planetary Science Conference outlines the geology work that such a helicopter could accomplish.

The paper, “Unraveling the Origin and Petrology of the Martian Crust with a Helicopter,” notes there are several outstanding questions about the makeup and history of Mars’ surface, especially with recent discoveries of unexpected dichotomies in the composition of basaltic rocks. In observations from the Mars rovers and orbital spacecraft, some regions appear to have been influenced by water while some have not.

“Up to last decade, we thought that magmatic rocks were only basaltic on Mars,” said Valerie Payré from the University of Iowa, the paper’s lead author. “But with recent rover and orbital measurements, we observed that there is a wide diversity of magmatic rocks similar to what we see on Earth.”

Payré explained via email that there are rocks on Mars with elevated silica concentrations called felsic rocks – feldspar and silicate — that are rich in elements and were not expected to be found on the Martian surface.

“We measured these with the Curiosity rover and have some hints of where there might be others using orbital measurements,” Payré said. “However, close-up images (millimetric scale) and composition analyses are lacking from the orbital dataset to know if these felsic rocks are widespread on Mars or just at a few locations. This is yet highly important to understand what the crust of Mars is made of and if it is similar to Earth’s crust, which has implications regarding the formation of the planet and even past climate.”

First X-ray view of Martian soil – feldspar, pyroxenes, olivine revealed (Curiosity rover at “Rocknest”, October 17, 2012). Credit: NASA/JPL-Caltech/Ames

Payré and her team feel that a helicopter would be perfect to explore places where a rover could never traverse, such as terrains that are too high in altitude, since landing there would require too much fuel.

The instruments they propose include a miniaturized visible and near-infrared (VNIR) spectrometer for small scale mineralogical mapping and a small Laser Induced Breakdown Spectrometer (LIBS) with a micro-imager, an instrument similar to the ChemCam laser instrument on both the Curiosity and Perseverance rovers. In their paper, the team writes that a helicopter with these instruments could travel kilometers to detect promising felsic terrains, and measure their composition at a micron scale.

“We could fly over these possible felsic terrains and look at their minerals using a visible/near infrared spectrometer, land on locations of interest, take close-up images, and measure the compositions of these rocks with the LIBS,” Payré said. “We could finally know what Mars’ crust is, and better constrain how it formed.”

A graphic show the parts of the Ingenuity helicopter. Credit: NASA

There could also be an onboard a magnetometer, which measures magnetic field anomalies, to better understand how Mars’ magnetic field operated, which is still uncertain. Mars does not presently have a global magnetic field, but had one early in its lifetime.

“Such payload would finally enable us to better understand the past climate on Mars by measuring the composition and minerals of sedimentary rocks of various age,” Payré told Universe Today.

A conceptual design paper published in 2020 proposed a Mars hexacopter with a mass of about 31 kg (70 lbs) and a total diameter of just over four meters (13 feet). Each set of rotors would have blades about 0.64 meters (2 ft) long.  The helicopter would be powered by a rechargeable solar cell. This would not only power the rotors, but the desired scientific instruments. 

A model of NASA’s Mars Science Helicopter concept. Credit: NASA.

This helicopter could move as fast as 30 meters a second (60 mph) but also could hover over a spot for as long as five minutes. Engineers from Ames Research Center, the Jet Propulsion Lab and the University of Maryland wrote that MSH could fly with a range of up to 10 km (6.2 miles) per flight. With this speed and range, MSH could potentially cover as much ground in a few days as rovers like Perseverance and Curiosity have traversed in years.

“The fact that a helicopter can fly would facilitate the mission to visit to places that would be inaccessible for a rover, and we could access locations that we never imagined before,” Payré said.

Payré and team proposed several landing sites including Gale Crater Gale crater where evolved felsic rocks were found by the Curiosity Rover; the massive canyon of Valles Marineris, where orbital observations have revealed a deep crust with feldspar-bearing rocks; and Hellas basin, 2,300 km impact crater known to have layers of feldspar. 

Annotated view of Valles Marineris from the High-Resolution Stereoscopic Camera (HRSC) on the Mars Express spacecraft. Credit: ESA/DLR/FU Berlin (G. Michael)

The post The Mars Science Helicopter Could be an Airborne Geologist on Mars appeared first on Universe Today.

Categories: Science

What are Fields?

Science blog of a physics theorist Feed - Thu, 03/21/2024 - 5:21am

One of the most challenging aspects of writing a book or blog about the universe (as physicists currently understand it) is that both writer and reader must confront the concept of fields. The problem isn’t that fields are intrinsically that complicated. It’s that they are an unfamiliar abstraction — and novel abstractions of any sort are always difficult both for a writer to describe and for a reader to grasp.

What I’ll do today is give an explanation of fields that is complementary to the one that appears in the book’s chapters 13 and 14. The book’s approach is slow, methodical, and detailed, but today’s will be more of an overview, brief and relatively shallow, and presented in a different order. You will likely come away with many unanswered questions, but the book should help with that. And if the book and today’s post combined are still not enough, you can ask a question in the comments below, or on the book question page.

Negotiating the Abstract and the Concrete

To approach an abstract concept, it’s always good to have concrete examples. The first example of a field of the cosmos that comes to mind, one that most people have heard of and encountered, is the magnetic field. Unfortunately, it’s not all that concrete. For most of us, it’s near-magic: we can see and feel that it somehow makes little metal blocks cluster together or stick to refrigerator doors, but the field itself remains remote from human experience, as it can’t be seen or felt directly.

There are fields, however, that are less magic-seeming and are known to everyone. The most obvious, though it often goes unrecognized, is the “wind field” of the atmosphere. Since we all experience it, and since weather maps often depict it, that’s the field I focused on in the book’s chapter 13. I hoped that by using it as an initial example, it would make the concept of “field” more intuitive for many readers.

But I knew that inevitably, no matter what approach I chose, it wouldn’t work for all readers. (My own father, for instance, has had more trouble making sense of that part of the book than any other.) Knowing this would happen, I’ve planned from the beginning to give alternate explanations here, to offer readers multiple roads into this unfamiliar concept.

Ordinary Fields

In general, I find that the fields of the universe — I’ll call them “cosmic fields”, for short — are not the best starting point. That’s because they are mostly unfamiliar, and are intrinsically confusing and obscure even to physicists.

Instead, I’ll start with fields of ordinary materials, like water, air, rock and iron. We will see there is an interesting analogy between the fields of materials and the fields of the cosmos, one which will give us a great deal of useful intuition.

However, this analogy comes with a strongly-worded caution, warning and disclaimer, because the cosmos has properties that no ordinary material could possibly have. (See chapter 14 for a detailed discussion.) For this reason, please be careful not to take the analogy to firmly to heart. It has many merits, but we will definitely have to let some of it go — and perhaps all of it.

Air and its Fields

So let’s start with a familiar material and its properties: the air that makes up the Earth’s atmosphere, and some of the properties of the air that are recorded by weather stations. As I write this, the weather station at Boston’s Logan Airport is reporting on conditions there, stating that it measures

  • Wind W 10 mph
  • Pressure 29.71 in (1005.8 mb)
  • Humidity 43%

There are similar weather stations scattered about the world that give us information about wind, pressure and humidity at various locations. But we don’t have complete information; obviously we don’t have weather stations at every point in the atmosphere!

Nevertheless, at all times, every point in the atmosphere does in fact have its own wind, pressure, and humidity, even if there’s no weather station there to measure it. Each of these properties of the air is meaningful throughout the atmosphere, varies from place to place, and changes over time.

Now we make our first step into abstraction. We can define the air’s property of pressure, viewed all across the atmosphere, as a field. When we do this, we view the pressure not as something measured at a particular place and time but as if it were measured everywhere in space and time. This makes it into a function of space and time — a function that tells us the pressure at all points in the atmosphere and at all times in Earth’s history. If we define x,y,z to be three coordinates that specify where we are in the three-dimensional atmosphere, and t to be a coordinate that specifies what time it is, then the pressure at that particular place and time can be written as P(x,y,z,t) — a function that takes in a position and a time and outputs the pressure at that position and time.

For instance, consider the point (xB,yB,zB) corresponding to Logan airport, and the time t0 when I was writing this article. According to the weather station whose measurements I reported above, the value of the pressure field at that position and moment, P(xB, yB, zB, t0), was equal to 29.71 inches of mercury (or, equivalently, 1005.8 millibarns).

Any one weather station’s report tells us only what the pressure is at a particular location and moment. But if we knew the pressure field perfectly at a moment t — if we had complete knowledge of the function P(x,y,z,t) — we’d know how strong the pressure is everywhere in the atmosphere at that moment.

In a similar way, we can define the “wind field” and the “humidity field” (or “water-vapor density field”) to capture what the wind and humidity are doing across the atmosphere’s entire expanse. Each field’s value at a particular location and time tells us what a measurement of the corresponding property would show at that location and time.

Maps and images illustrating three atmospheric fields: (top to bottom) air pressure, average wind patterns, and water vapor (humidity). Credits: NOAA.

These three fields interact with each other, with other fields, and with external effects (such as sunlight) to create weather. Detailed weather forecasting is only possible because scientists have largely understood how these fields behave and how they affect one another, and have expressed their understanding through math equations that have been programmed into weather forecasting computers.

Air as a Medium

Abstracting even further, we may think of the air of the atmosphere as an example of what one would call an ordinary medium — a largely uniform substance that occupies a wide area for an extended period of time. The water of the oceans is another example of an ordinary medium. Others include the rock of the Earth, the plasma that makes up the Sun, the gas of Jupiter’s atmosphere, a large block of iron or copper or lead, the pure neutron material of a neutron star, and so on.

Each medium has a number of properties, just as air does. Its properties that vary from place to place and change predictably with time can be viewed as fields, in the same way that air pressure and wind can be viewed as fields.

And so we reach a highly abstract level: an ordinary field is

  • a property of an ordinary medium . . .
  • that can be measured, . . .
  • varies from place to place, . . .
  • and changes with time in a manner that (at least in principle) is predictable.

Let’s look at a few examples to make this more concrete.

  • For the oceans, fields include the current (the flow of the water) and the water pressure.
  • The fields of layered sedimentary rock include the rock’s density and the degree to which (and direction in which) its layers have been bent.
A layer of bent sedimentary rock sits above layers of flat sedimentary rocks. Credit: Michael C. Rygel via Wikimedia Commons
  • For a block of iron, fields include the iron’s density (the number of atoms in a cube of material divided by the cube’s volume), the orientation of its crystal structure (which might be bent in places), and the average local orientation of its atoms; the latter, usually called the “magnetization field”, determines if the iron will act as a magnet or not.
Figure 32 from Chapter 13 of Waves in an Impossible Sea (credit C. Cesarotti), showing the atoms in a piece of iron. The density field (how closely spaced the atoms are) and the crystal-orientation field (the orientation of the grid of atoms) are both uniform here. But the atoms’ orientations, shown as a little arrow on each atom, change from place to place, and cancel each other out in the middle section. As a result, the iron’s “magnetization field” points in different directions at the two ends (grey arrows) and is zero in the middle.

This manner of thinking is a commonplace, and a powerful one, for physicists who spend their careers studying ordinary materials, such as metals, superconductors, fluids, and so on. Each type of ordinary medium has ordinary fields that characterize it, and these fields interact with each other in ways that are specific to that medium. In some cases, even if we knew nothing about the medium, knowing all its fields and all their interactions with one another might allow us to guess what the medium is.

Cosmic Fields

We can now turn to the cosmos itself. Over the last two centuries, physicists have found that there are quite a few quantities that can be measured everywhere and at all times, that vary from place to place and from moment to moment, and that affect one another. These quantities have also been called “fields”. Just to be clear, I’ll call them “cosmic fields” to distinguish them from the “ordinary fields” that we have just been discussing.

In many ways, cosmic fields resemble ordinary fields. They act in many ways as though the cosmos were a medium, and as though the fields represent some of the properties of that medium.

Empty Space as a Medium

Einstein himself gave us a good reason to think along these lines. In his approach to gravity, known as general relativity, the empty space that pervades the universe should be viewed as a sort of medium. (That includes the space inside of objects, such as our own bodies.) Much as pressure represents a property of air, Einstein’s gravitational field (which generates all gravitational effects) represents a property of space — the degree to which space is bent. We often call that property the “curvature” or “warping” of space.

The list of cosmic fields is extensive, and includes the electromagnetic field and the Higgs field among others. Should we think of each of these fields as representing an additional property of empty space?

Maybe that’s the right way to think about these other cosmic fields. But we must be wary. We don’t yet have any evidence that this is the right viewpoint.

The Fields of Empty Space?

This brings us to the greatest abstraction of all, the one that physicists live with every day.

  • Cosmic fields may be properties of the medium that we call “empty space”. Or they may not be.
  • Even if they are, though, we have no idea (with the one exception of the gravitational field) what properties they correspond to. Our understanding of empty space is still far too limited.

This tremendous gap in our understanding might seem to leave us completely at sea. But fortunately, physicists have learned how to use measurement and math to make predictions about how the cosmic fields behave despite having no understanding what properties of empty space these fields might represent. Even though we don’t know what the cosmic fields are, we have extensive knowledge and understanding of what they do.

An Analogy Both Useful And Problematic

It may seem comforting, if a bit counterintuitive, to imagine that the universe’s empty space might in fact be a something — a sort of substance, much as air and rock are substances — and that this cosmic substance, like air and rock, has properties that can be viewed as fields. From this perspective, a central goal of modern theoretical physicists who study particles and fields is the following: to figure out what the cosmos is made from and what properties the various fields correspond to.

Imagine that it was your job to start from weather reports that look like this:

  • Field A: W 18 mph
  • Field B: 29.62 in (1003.0 mb)
  • Field C: 63%

and then try to deduce, from a huge number of these reports, what the atmosphere is made from and what properties the fields called “A”, “B” and “C” correspond to. This is akin to what today’s physicists have to do. We have discovered various fields that we can measure and study, and to which we’ve given arbitrary names; and we’d like to infer from their behavior what empty space really is and what its fields actually represent.

This is an interesting way to think about what particle physicists are doing nowadays. But we should be careful not to take it too seriously.

  • First, the whole analogy, tempting as it is, might be completely wrong. It may be that the fields of the universe represent something completely different from the ordinary properties of an ordinary medium, and that the seeming similarity of the two is deeply misleading.
  • Second, the analogy is definitely wrong in part: we already know that the universe cannot be like an ordinary medium. That’s a long story (explained carefully in the book’s chapter 14), but the bottom line is that empty space has properties that no ordinary medium can possibly have.

Nevertheless, the notion that ordinary media made from ordinary materials have ordinary fields, and that empty space has cosmic fields that bear some rough resemblance to what we see in ordinary media, is useful. The analogy helps us gain some basic intuition for how fields work and for what they might be, even though we have to remain cautious about its flaws, known and unknown. This manner of thinking was useful to Einstein in the research of his later years (even though it led to a dead end), and it also arises naturally in string theory (which may or may not be a dead end.)

Whether, in the long run, this analogy proves more beneficial than misleading is something that only future research will reveal. But for now, I think it can serve experts and non-experts alike, as long as we keep in mind that it cannot be the full story.

Categories: Science

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