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Beautiful nature world, Улица Каткова, Kyiv (2026)

25/02/2023

Lightsabers – fictitious swords made of… something glowy – are the quintessential melee weapon of the Star Wars universe. No self-respecting Jedi would be complete without one.

But depending on how they work, they just might be the most impractical way to duel a Sith. In the worst case, they'd probably run afoul of some pretty fundamental physics that hold the whole Universe together.

That's not to say we couldn't come close.

How do lightsabers cut stuff?
Based on decades of storytelling, movies, and fan lore, the slashy bit of the lightsaber is allegedly made of plasma.

Plasma is an energetic gas consisting of charged particles, and is indeed commonly used in industries to cut through electrically conductive material. An ionized stream of gas blown through compressed air forms a circuit with the material to be cut, through which a current can flow and heat a material past its melting point.

That heat can be pretty extreme, too, exceeding 20,000 degrees Celsius in some instances: more than enough to reduce your protocol droid to a dribbling pile of scrap.

But if you're wanting to slice the arm off a hungry wampa, or even do something as simple as cut down a tree or break a window, you're going to have a hard time.

Despite this, plasma streams do have their uses in non-industrial fields. Low-temperature blades of ionized particles have been developed that can lay waste to microbes, and in theory can be ramped up in energy to cauterize small areas of flesh.

In 2020, gadget makers Hacksmith Industries built a 'lightsaber' based on a high temperature stream of plasma that hit temperatures of around 4,000 degrees Celsius. They demonstrated its ability to burn through a variety of materials, if a little slower than the average Jedi master might have time for.

The biggest problem with a plasma-based sword is the source of the gas. Assuming an efficient way to heat material, those charged particles still need to come from somewhere. Hacksmith's prototype sword was tethered to heavy tanks of gas, and even then, the stream of hot plasma was too brief for an extended battle.

It's a problem ion drive technology has faced, and at least partially solved. Typical sources of fuel in the form of the expensive inert element xenon need to be compressed, demanding bulky containers that add excessive mass to any space craft using it.

Packing a pellet of iodine which can sublimate into a gas would be a far more efficient use of space. Unfortunately, iodine isn't as inert as xenon, demanding ceramic engine parts that can handle its corrosive effects.

Though useful for accelerating tiny craft through a vacuum, this kind of plasma is unlikely to do more than give you third degree burns at full force.

New innovations in engine technology are taking care of this, though it's left to be seen if it would ever play a role in any kind of high-energy portable cutting tool.

What about a sword made from actual light?
Few young Star Wars fans have been able to hold back the temptation of swinging a flashlight beam around while making the famous lightsaber buzzing noise.

If we assume a lightsaber is truly made of light, could it materialize into a blade capable of clashing, cutting, and cauterizing?

Light is a ripple in the electrogmagnetic field which takes the form of particles called photons. Photons have characteristics that put them into a category of matter called bosons which in technical terms are particles with a spin value of a whole integer, like 1, 2, or even zero.

In non-technical terms, this whole value provides a symmetry that allows two or more particles to share certain properties, such as the same space. No matter how many photons are shoved into a box, there's technically always room for more.

This can make for a pretty impressive weapon, potentially.

Lining up the phases of a single color of light by bouncing a bunch of photons back-and-forth in the right sized chamber would allow those photons to collectively strike with a huge amount of energy. The process is known as light amplification by stimulated emission of radiation – you undoubtedly know that as 'laser'.

But to become a sword that can parry and block other swords, a laser 'blade' would also need to interfere with other lasers in the tangible ways that electrons, protons, and neutrons do.

standard model of particle physics chart

Particles with fractions of spin, like half or 5/2, are complicated by a principle that says multiple particles with the exact same quantum states simply can't overlap. Electrons surrounding an atom's nucleus, for instance, jostle with one another in ways that allow for basic chemistry to take place. Without this principle, we'd live in a Universe as tangible as a ghost.

Electrons also maintain their space by way of exchanging the electromagnetic force, using photons to tell other particles with the same charge to keep their distance.

Photons themselves don't exchange forces with one another as electrons and protons might do, which all adds up to waves of light being fairly oblivious to the existence of other waves of light.

There are loopholes in physics where photons can indirectly 'collide', so to speak, generating charged particles out of the residual energy. Experiments using high-powered lasers tell us a thing or two about the behavior of radiation in the early Universe, in an era long, long ago, but sadly it won't give us a stick of light we can use to parry laser bolts.

Until we discover something truly revolutionary about the behavior of light or plasma, glowing lightsaber swords will remain in the realm of pure fantasy.

All Explainers are determined by fact checkers to be correct and relevant at the time of publishing. Text and images may be altered, removed, or added to as an editorial decision to keep information current.

25/02/2023

The Dunning-Kruger effect is a purported bias in human thinking that leads us to misjudge our abilities in contrast to our actual skill level.

It is named after American social psychologists David Dunning and Justin Kruger, who since the late 1990s have conducted a series of investigations into our ability to self-assess our own performance at various tasks such as logical reasoning, grammar, emotional intelligence, and humor.

What does the Dunning-Kruger effect mean?
According to their results, we all overestimate our ability to succeed at particular tasks when our actual skill in that task is relatively low, and in some cases underestimate our chance of success when our skill is high.

This tendency to overestimate, they've found, stems not from a mistaken assessment of others' abilities, but due to a lack of insight into our own. By improving our ability to judge the accuracy of information, we can evaluate our own knowledge better and estimate our own abilities more reliably.

How is the Dunning-Kruger effect misunderstood?
Since the dawn of Western philosophy, one of the marks of wisdom has been humility in knowledge. In the words of 20th century British philosopher Bertrand Russell, "the fundamental cause of the trouble in the modern world today is that the stupid are cocksure while the intelligent are full of doubt."

So it comes as no surprise that the Dunning-Kruger effect would be so readily adopted in reflection of this age-old truism. The results are often interpreted as generalizations of intelligence along a dividing line – between the smart and stupid, so to speak.

It's often misinterpreted as "overconfidence in oneself", or as a graph portraying an expert-level confidence among the incompetent.

But Dunning and Kruger's investigations apply less to individuals and more to discrete fields of knowledge and skill. We're all likely to overestimate our ability to recall or identify factual information, or exercise a skill, as our actual performance in that area drops below the top quartile.

That isn't about 'incompetent' folks, but about most people in any given expertise. You can have a high IQ, know all there is to know about neurosurgery, have zero handicap on your golf game, and cook a mean lasagna, and still be subject to the Dunning-Kruger effect when discussing domestic politics.

Is it possible the Dunning-Kruger effect isn't even real?
Recent investigations into the method used by Dunning and Kruger to analyze their data have raised cause to be suspicious, if not doubtful of the strength of the Dunning-Kruger effect.

By producing pools of data in a completely randomized fashion and then separating the test and prediction figures into the quartiles (the bottom performers, the top performers and two blocks in the middle) used by Dunning and Kruger, several researchers have demonstrated it's possible to get the same results.

This and other criticisms imply the effect might be the result of a statistical artifact called a 'regression toward the mean' – a natural consequence of randomness and repeated sampling.

This doesn't rule out such an effect in specific areas. It does leave plenty of room for debate over the nature of self-awareness in our own knowledge.

Even if the Dunning-Kruger effect was found to be a complete illusion, that age-old advice of reserving doubt would still be worth keeping in mind.

All Explainers are determined by fact checkers to be correct and relevant at the time of publishing. Text and images may be altered, removed, or added to as an editorial decision to keep information current.

23/02/2023

Following the February 3 train derailment in East Palestine, Ohio, users on social media began sharing photos of an ominous black cloud hanging over the town – and fears that the disaster would become the new Chernobyl.

A fire engulfed a Norfolk Southern train after 50 of its 150 cars derailed. The train carried 10 cars full of hazardous materials, including vinyl chloride, a colorless gas used in the creation of the plastic PVC, which was released as a result of the derailment. In sunlight, it can be broken down into chemicals like formaldehyde.

Other flammable chemicals, like ethylene glycol monobutyl ether, ethylhexyl acrylate, butyl acrylate, and isobutylene were also present in the cars and released into the environment, according to a list compiled by the EPA.

Many of these chemicals are carcinogenic or potentially carcinogenic, or are considered respiratory and eye irritants.

The toxicity of these chemicals initially prompted concerns about the health and safety of residents. Then came the comparisons to another disaster, one that happened nearly 40 years ago: The nuclear disaster in the city of Pripyat on April 26, 1986, which resulted in the spread of radioactive contaminants in Ukraine and across Europe.

Although the intense imagery from Ohio might have onlookers believe the state has a mini Chernobyl on its hands, the scale of Chernobyl's destruction was much worse. However, the environmental impact of the East Palestine incident should not be ignored, experts say.

Chemicals released during both disasters were carcinogenic, but Chernobyl was radioactive
The Chernobyl incident occurred after a series of safety measures during a nuclear reactor test were ignored, resulting in a huge explosion and fire that spread large amounts of radioactive chemicals like plutonium, iodine, strontium, and cesium.

Although carcinogenic chemicals were found on the train in East Palestine, and multiple small explosions occurred following the derailment, many were burned in a controlled fashion – which resulted in the large black cloud over the city. The chemicals in the East Palestine incident are also not as potent as the nuclear waste in Chernobyl.

Nobody died as a result of the East Palestine chemical spill
Two people died immediately following the explosion at Chernobyl. A month later, nearly 30 emergency workers died as a result of acute radiation sickness and one of cardiac arrest. Following the accident, it's estimated that thousands may have died as a result of cancers and blood diseases caused by chemical exposure from the Chernobyl power plant – although these figures are still being disputed.

In East Palestine, no deaths have been reported as a result of the derailment or the following fires and explosions, although residents say they are experiencing respiratory issues, sore throats, irritated eyes, headaches, and other ailments.

Multiple class action lawsuits have been filed against Norfolk Southern Railroad Company following the derailment, with residents saying that the company should be responsible for the health effects to residents and the environment.

There have been reports of a significant amount of animal deaths
Following the controlled burn of chemicals to prevent a deadly explosion, residents say foxes, chickens, and other domesticated animals have died. There have also been approximately 3,500 dead fish counted in four nearby waterways, the Ohio Department of Natural Resources said Tuesday.

In Chernobyl, the effects on animal life have not been fully determined. The explosion had immediate effects on the health of animal populations and many plants and animals mutated as a result of radioactive exposure, according to the International Atomic Energy Agency.

East Palestine resulted in an evacuation, but it was short-lived
After the derailment, close to 2,000 residents in East Palestine were asked to evacuate.

Prior to the controlled burn in the Ohio city, the evacuation area was extended to a 2-mile-wide radius zone that was established on February 6.

On February 8, officials announced that residents could return to their homes after the EPA determined that it did not detect contaminants at "levels of concern" in air and water samples. The Ohio EPA also announced that it would monitor soil for potential groundwater leaching of chemicals, WESA reported.

But Chernobyl is still considered uninhabitable
The Chernobyl explosion contaminated 150,000 square kilometers in Belarus, Russia, and Ukraine, and resulted in the evacuation of around 350,000 people who had to leave all their belongings behind. A 19-mile-radius nuclear exclusion zone was established around the power plant that still exists today.

During the war in Ukraine, Russian troops returned to the Chernobyl plant and began digging trenches around the area. Ukraine's state nuclear agency claimed in March that Russians suffered "significant doses of radiation." Russian soldiers later left the plant in a state of disarray, Ukrainian workers said in June.

Hundreds of mostly elderly people have also returned to the zone – or never left – to live the rest of their lives in their hometowns.

"Those who left are worse off now," one woman said in the documentary Babushkas of Chernobyl.

21/02/2023

Early-onset colore**al cancer incidence among the young, defined as those under age 50, has been rising globally since the early 1990s. Rates for colon and re**al cancers are expected to increase by 90 percent and 124 percent, respectively, by 2030.

One suspected reason behind this trend is increased global consumption of a Westernized diet that consists heavily of red and processed meats, added sugar, and refined grains. Sixty percent of the Standard American Diet, also known as "SAD," is made up of ultra-processed food such as industrial baked sweets, soft drinks, and processed meat. SAD is associated with an increased risk of colore**al cancer.

One aspect of ultra-processed foods I'm concerned about is how colorful they are. This characteristic is on full display in many delicious foods and treats present during the year-end holidays.

However, many of the colors that make up candy canes, sugar cookies, and even cranberry sauce and roast ham, are synthetic. And there's some evidence that these artificial food dyes may trigger cancer-causing processes in the body.

As the director of the Center for Colon Cancer Research at the University of South Carolina, I have been studying the effects of these synthetic food dyes on colore**al cancer development.

While research on the potential cancer risk of synthetic food dyes is only just starting, I believe that you may want to think twice before you reach for that colorful treat this holiday season.

What are synthetic food dyes?
The food industry uses synthetic dyes because they make food look better. The first food dyes were created from coal tar in the late 1800s. Today, they are often synthesized from a chemical derived from petroleum called naphthalene to make a final product called an azo dye.

Food manufacturers prefer synthetic dyes over natural dyes like beet extract because they are cheaper, brighter, and last longer. While manufacturers have developed hundreds of synthetic food dyes over the past century, the majority of them are toxic. Only nine are approved for use in food under U.S. Food and Drug Administration policy, and even fewer pass European Union regulations.

What drives colore**al cancer?
DNA damage is the primary driver of colore**al cancer. When DNA damage occurs on cancer driver genes, it can result in a mutation that tells the cell to divide uncontrollably and turn cancerous.

Another driver of colore**al cancer is inflammation. Inflammation occurs when the immune system sends out inflammatory cells to begin healing an injury or capture disease-causing pathogens.

When this inflammation persists over time, it can harm otherwise healthy cells by releasing molecules called free radicals that can damage DNA.

Another type of molecule called cytokines can prolong inflammation and drive increased cell division and cancer development in the gut when there isn't an injury to heal.

Long-term poor dietary habits can lead to a simmering low-grade inflammation that doesn't produce noticeable symptoms, even while inflammatory molecules continue to damage otherwise healthy cells.

Synthetic food dyes and cancer
Although none of the FDA-approved synthetic food colors are classified as carcinogens, currently available research points to potential health risks I and others find concerning.

For example, the bacteria in your gut can break down synthetic dyes into molecules that are known to cause cancer. More research is needed on how the microbiome interacts with synthetic food coloring and potential cancer risk.

Studies have shown that artificial food dyes can bind to the DNA and proteins inside cells. There is also some evidence that synthetic dyes can stimulate the body's inflammatory machinery. Both of these mechanisms may pose a problem for colon and re**al health.

Synthetic food dyes have been found to damage DNA in rodents. This is supported by unpublished data from my research team showing that Allura Red, or Red 40, and Tartrazine, or Yellow 5, can cause DNA damage in colon cancer cells with increased dosages and length of exposure in vitro in a controlled lab environment.

Our results will need to be replicated in animal and human models before we can say that these dyes directly caused DNA damage, however.

Finally, artificial food coloring may be of particular concern for children. It's known that children are more vulnerable to environmental toxins because their bodies are still developing. I and others believe that this concern may extend to synthetic food dyes, especially considering their prevalence in children's food.

A 2016 study found that over 40 percent of food products marketed toward children in one major supermarket in North Carolina contained artificial food coloring. More research needs to be done to examine how repeated exposure to artificial food dyes may affect children.

Lowering your risk of colore**al cancer
A few treats during the holidays won't cause colore**al cancer. But a long-term diet of processed foods might. While more research is needed on the link between synthetic food dyes and cancer, there are evidence-based steps you can take now to reduce your risk of colore**al cancer.

One way is to get screened for colon cancer. Another is to increase your physical activity. Finally, you can eat a healthy diet with more whole grains and produce and less alcohol and red and processed meat. Though this means eating fewer of the colorful, ultra-processed foods that may be plentiful during the holidays, your gut will thank you in the long run.

Lorne J. Hofseth, Professor and Associate Dean for Research, College of Pharmacy, University of South Carolina.

18/02/2023

The violent fingers of electricity that struck a sand dune in Nebraska have left behind a configuration of crystal rarely found in nature.

Inside a piece of fulgurite – or 'fossilized lightning' – created by a powerful bolt of electricity traveling into and fusing sand, scientists have found a quasicrystal, an arrangement of matter once thought to be impossible.

This discovery suggests there are previously unknown formation pathways for quasicrystals, opening up new avenues for their synthesis in the laboratory.

"The current investigation was designed to explore a different possible nature-inspired mechanism for generating quasicrystals: electrical discharge," write a team of researchers led by geologist Luca Bindi of the University of Florence in Italy in their paper.

"The discovery of a quasicrystal in a fulgurite with rarely observed 12-fold symmetry and a not been reported previously composition indicates that this approach may also be promising in the laboratory."

The Sandhills fulgurite. The quasicrystal was found in the section on the right. (Bindi et al., PNAS, 2022)
Most crystalline solids in nature, from the humble table salt to the toughest diamonds, follow the same pattern: their atoms are arranged in a lattice structure that repeats in three-dimensional space.

Solids that don't have these repeating atomic structures – amorphous solids like glass – are generally an atomic mess, a jumble of atoms mooshed in together with no rhyme or reason.

Quasicrystals break the rule – their atoms are arranged in a pattern, but that pattern does not repeat.

When the idea of quasicrystals first emerged in the 1980s, the concept was thought impossible. Solids could be either crystalline or amorphous, not this weird in-between. But then scientists actually found them, in both the laboratory setting and in nature, deep inside meteorites.

Since then, scientists have determined that quasicrystals in nature can only form under extreme conditions, with incredibly high shock, temperature, and pressure.

Hypervelocity meteorite impacts is one such setting; in fact, for a long time, it was the only setting in which they had been found in nature, and was thus thought to be possibly the only place they could occur.

Then Bindi and his colleague, physicist Paul Steinhardt of Princeton University, along with their team, found a quasicrystal forged during a nuclear bomb test in 1945. Although not exactly 'natural' conditions, the discovery suggested that there might be other settings in which quasicrystals could form.

Lightning is one of the most powerful forces in nature, striking with extreme speed, and can heat the air it passes through to 5 times the temperature of the surface of the Sun.

And, when it hits the ground in the right place with enough power, it can melt sand, leaving behind a fulgurite – a 'fossil' of the path it traveled through the ground.

All the ingredients are there: shock, temperature, and pressure. So Bindi, Steinhardt, and their colleagues set about investigating fulgurites for quasicrystals.

They obtained a fulgurite sample from the Sandhills region of Nebraska, retrieved from a site close to a fallen power line, and subjected it to scanning electron microscopy and transmission electron microscopy, to determine its chemical composition and crystalline structure.

High-angle annular dark field transmission electron microscopy image of a section of the quasicrystal, demonstrating its order and disorder. (Bindi et al., PNAS, 2022)
The sample consisted of fused sand, and traces of melted conductor metal from the power line. Within it, the researchers found a dodecahedral (twelve-sided) quasicrystal with the previously unreported composition Mn72.3Si15.6Cr9.7Al1.8Ni0.6.

The atoms in this quasicrystal formed a pattern with a 12-fold symmetry, arranged in a quasicrystalline order impossible in normal crystals.

It's unclear whether lightning or the power line were responsible for the electricity that created the fulgurite; however, based on their analysis, the team determined that the sand had to have been heated to at least 1,710 degrees Celsius (3,110 degrees Fahrenheit) to create the fulgurite.

This, the researchers say, gives clues about how scientists could create quasicrystals in the lab. Quasicrystals found in a meteorite suggested that shock synthesis could be one way; lightning offers new possibilities.

"The discovery of a dodecagonal quasicrystal formed by a lightning strike or downed power line suggests that electric discharge experiments may be another approach to be added to our arsenal of synthesis methods," they write in their paper.

And the discovery points to what could be previously overlooked quasicrystal formation pathways – both on Earth, and beyond.

"The results presented here, together with the trace element abundances measured in natural quasicrystals, open the possibility that electric discharge in the early solar nebula may have played a key role that not only accounts for the requisite reducing conditions but also promotes quasicrystal formation."

16/02/2023

A gargantuan effort by a huge international team of scientists has just given us the most precise map of the all matter in the Universe obtained to date.

By combining data from two major surveys, the international collaboration has revealed where the Universe does and doesn't keep all its junk – not just the normal matter that makes up the planets, stars, dust, black holes, galaxies, but the dark matter, too: the mysterious invisible mass generating more gravity than the normal matter can account for.

The resulting map, showing where the matter has congregated over the 13.8-billion-year lifespan of the Universe, will be a valuable reference for scientists looking to understand how the Universe evolved.

Indeed, the results already show that the matter isn't distributed quite how we thought it was, suggesting there could be something missing from the current standard model of cosmology.

According to the current models, at the point of the Big Bang, all the matter in the Universe was condensed into a singularity: a single point of infinite density and extreme heat that suddenly burst and spewed forth quarks that rapidly combined to form a soup of protons, neutrons and nuclei. Hydrogen and helium atoms came a few hundred thousand years later; from these, the entire Universe was made.

How these early atoms spread out, cooled, clumped together, formed stars and rocks and dust, is detective work based on how the Universe around us appears today. And one of the major clues we've used is where all the matter is now – because scientists can then work backwards to figure out how it got there.

But we can't see all of it. In fact, most of the matter in the Universe – around 75 percent – is completely invisible to our current detection methods.

We've only detected it indirectly, because it creates stronger gravitational fields than there should be just based on the amount of normal matter. This manifests in such phenomena as galaxies spinning faster than they should, and a little quirk of the Universe we call gravitational lensing.

When something in the Universe has enough mass – for example, a cluster of thousands of galaxies – the gravitational field around it becomes strong enough to influence the curvature of space-time itself.

That means that any light that travels through that region of space does so along a curved path, resulting in warped and magnified light. These lenses, too, are stronger than they should be if they were only being created by normal matter.

To map the matter in the Universe, researchers compared gravitational lens data collected by two different surveys – the Dark Energy Survey, which collected data in near-ultraviolet, visible, and near-infrared wavelengths; and the South Pole Telescope, which collects data on the cosmic microwave background, the faint traces of radiation left over from the Big Bang.

Maps of the sky compiled from data from the Dark Energy Survey (left) and the South Pole Telescope (right). (Yuuki Omori)
By cross-comparing these two datasets taken by two different instruments, the researchers can be much more certain of their results.

"It functions like a cross-check, so it becomes a much more robust measurement than if you just used one or the other," says astrophysicist Chihway Chang of the University of Chicago, who was the lead author on one of three papers describing the work.

Lead authors on the two other papers are physicist Yuuki Omori of Kavli Institute for Cosmological Physics and the University of Chicago, and telescope scientist Tim Abbott of NOIRLab's Cerro Tololo Inter-American Observatory.

The resulting map, based on galaxy positions, lensing of galaxies, and lensing of the cosmic microwave background, can then be extrapolated to infer the matter distribution in the Universe.

This map can then be compared to models and simulations of the evolution of the Universe to see if the observed matter distribution matches theory.

The researchers did run some comparisons, and found that their map mostly matched current models. But not quite. There were some very slight differences between observation and prediction; the matter distribution, the researchers found, is less clumpy, more evenly spaced out than models predict.

This suggests that our cosmological models could use a tweak.

That's not really a surprise – there are a few mismatches between cosmological observation and theory that seem to suggest we're missing a trick or two, somewhere; and the team's findings are consistent with previous work – but the more accurate and complete our data is, the more likely we are to resolve these discrepancies.

There's more work to be done; the findings aren't certain, yet. Adding more surveys will help refine the map, and validate (or overturn) the team's findings.

And, of course, the map itself will help other scientists conduct their own investigations into the mysterious, murky history of the Universe.

Beautiful nature world

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