believing

We had been believing that dark matter existed. A new study believes that we were wrong

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For decades, cosmology has been sustained on a pillar as fundamental as mysterious: The dark matter. The invisible glue that, according to the standard model, keeps galaxies together and prevents the stars from being fired by centrifugal force.Represents 27% of the universebut it has a problem: nobody has seen or detected it. It only trusts that it will be there. But now A published study in Galaxies This conception of the concept has changed. The study. Research led by the physicist Rajendra P. Gupta From the University of Ottawa proposes an idea as elegant as radical: what if dark matter does not really exist? According to his work, this ghost component could actually be an ‘illusion’, a side effect caused by something we were assumed: that the fundamental constants of nature are ‘constant’. The importance. To understand the magnitude of this proposal you must first remember the origin of the problem. Specifically, we have to go to the 70s, where astronomer Vera Rubin noticed that the stars at the edges of the galaxies revolved at the same speed those of the center. This completely challenged Newton’s laws, something that is as if a person sitting on the outer edge spinning at the same speed as a sitting near the axis. Physically, it should be triggered. The solution that the scientific community adopted was the existence of a “dark matter”, an invisible mass that generates the extra gravity necessary to maintain cohesive galaxy. This concept became the cornerstone of the cosmological model known as ΛCDM (Lamda-Cold Dark Matter). This model works incredibly well to explain the large -scale universe, but after searches with ultrasensitive detectors and experiments in the LHC We have not found a single particle of dark matter. It has always ‘detected’ indirectly through its gravitational effect on visible objects. The proposal. This is where Gupta’s idea enters. Its model, called CCC + TL (Covarying Couplening Constants + Tirad Light), is based on two different ideas. The first one is the so -called ‘Covriant coupling constants’ (CCC). In this case, the model suggests that the fundamental constants of physics, such as the speed of light (c) or the universal gravitation constant (G), are not fixed. Instead, they evolve and change as the universe expands. This is not a completely new idea (the physicist Paul Dirac already flirted with her), but Gupta integrates it into a complete cosmological model. The second idea raised in the investigation is that of ‘tired light’. A concept that arrives directly from the old hypothesis of ‘tired light’, which postulates that light loses energy throughout its trip through the cosmos. In this case, the Gupta model suggests that the redness of the light of the distant galaxies is not only due to the expansion of the universe but to a combination of both effects. Although the “tired light” as the only explanation, has been widely refuted, its inclusion in this hybrid model is key to its calculations. New terms. Once these two new ideas are taken into account, it is time to modify Einstein’s field equations with these variable constants, the GUPTA model makes new mathematical terms appear. This is something that the author has baptized as “α-material” and “α-energy.” And this is where it is true magic: these terms, which are not a physical substance but an effect of the evolution of the laws of physics, generate the extra gravitational attraction that until now we attributed to dark matter. Dark matter would not be something to find, but a mathematical mirage. It is tested. Something to keep in mind is that theories can be very well written and look very good on paper, but logically they have to demonstrate. For this, Gupta used the SPARC database, a high quality catalog with the rotation curves of 175 galaxies. The method used was the reverse to the traditional. Instead of adding dark matter to justify rotation curves, Gupta took the curves observed and used its model to “subtract” the effect of “α-material”. The result should be the rotation curve generated only by visible (barionic) matter. Something that has wanted to materialize in a graphic taking as an example the NGC3198 galaxy. In this image, the blue line (VO) is the rotation speed observed in the galaxy. The points line (VB) is the speed that should have if only the visible matter existed, according to the estimates of SPARC and the discontinuous line (VBX) is the prediction of visible matter calculated by the GUPTA model. The similarity between the prediction of its model and the estimation of barionic matter is remarkable. Something that the author repeated for several galaxies with promising results to give a very forceful conclusion. A new paradigm. If the CCC+TL model is correct, its implications are huge. Not only would it eliminate the need for dark matter, but, according to the author, it could also explain dark energy and other cosmological enigmas, such as why the first galaxies Observed by James Webb They seem more mature than they should. You have to be cautious. This is, for now, a “proof of concept” as the author himself points out. This means that it is using simplifications, such as treating galaxies as perfect spheres, something that is far from reality in the universe. In addition, its dependence on “tired light” is a friction point with conventional cosmology. Models such as this should demonstrate that they can explain with the same precision as λCDM Key observations such as microwave background radiation or the accelerated expansion of the universe. A new advance. But what is clear with this research is that the scientific community is exploring alternatives, especially when the predominant model presents fissures, such as the absence of a direct proof of dark matter. The Gupta model is, for now, a fascinating possibility. A reminder that in science, the most entrenched truths can be questioned and that the solution to the greatest mysteries of the universe might not be to find something new, but in … Read more

We have been believing that Iran is “five years” from the nuclear bomb. In reality we only know how much uranium enriches

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Few phrases have been as repeated in the geopolitics of the West as “Iran is five years from the nuclear bomb.” For more than three decades, we have heard predictions that place the Iranian regime on the verge of crossing the atomic threshold, a stopwatch that restarts again and again without the prophecy becoming fulfilled. The real problem is not so much what we know about Iran’s nuclear program, as the immensity of what we do not know. And it is in that fog of uncertainty where the most dangerous decisions are cooked. A diffuse red line like Casus Belli. Israeli Prime Minister Benjamin Netanyahu has initiated a war against Iran framed in which the regime is “close to finishing the construction of a nuclear bomb.” This language transforms an old threat into an immediate danger, turning the rhetorical red line into a justification for war. Although the United States initially denies direct participation in the attack, political and military support has gone in crescendo. A Message of President Donald Trump In capital letters, “Iran can’t have a nuclear weapon!”, It works as a blank check for Israel. Thirty years of breached predictions. When a suspicion, and not an evidence, they are a reason for war, it is worth reviewing the newspaper library to put rhetoric in perspective. The feeling of “imminent nuclear bomb” in Iran is not new. It is a political construction that has been managing for decades, with Benjamin Netanyahu as its main architect. In 1992, Netanyahu already warned that Iran was “three or five years” to obtain nuclear weapons. In 2012, he starred in one of his most iconic moments at the UN, drawing a red line with a marker In a cartoon scheme of a pumpand ensuring that they would cross the line in the summer of 2013. Each period has been fulfilled without the weapon becoming materialized. What do intelligence agencies say. Although Israel had in the United States its main political ally, US intelligence agencies did not buy their rhetoric about Iran. In 2007, the National Intelligence Estimate De la CIA concluded with “high confidence” that Iran had stopped its nuclear militarization program, the AMAD Plan. The verification of this break came in 2015 with the Comprehensive Comprehensive Plan Joint (JCPOA), an agreement by which Iran limited uranium enrichment to 3.67% in exchange for the lifting of sanctions. The break that caught the fuse. Paradoxically, the withdrawal of the United States of the JCPOA in 2018, driven by the same rhetoric of the “imminent bomb”, caused the response that was intended to avoid. Iran began to enrich uranium at unprecedented levels: first 20% and then 60%, drastically shortening the theoretical deadlines for the pump and triggering the current crisis. Despite this, there are no evidence, beyond the expansion of enrichment plants, that Iran have the necessary technology or develop those weapons. Although, in honor of the truth, it is logical that there are no, since most of the activity is underground. Faith jump between enrichment and nuclear bomb. To understand how “near” Iran of the nuclear bomb is, you have to differentiate two key processes. The first is the fuel: the enrichment of uranium, the visible part of the process. It is about increasing the concentration of the fistible isotope 2 35 of the uranium from the 0.7% natural to 90% (the arms degree). Thanks to the withdrawal of the JCPOA, Iran accumulates a large amount of 60%enriched uranium. And moving from 60 to 90% is a technically feasible leap within a few weeks. However, Having the fuel is not having the enginewhat Anglo -Saxons call “weaponization.” A set of incredibly complex steps to convert the fistible material into a functional eye that can be mounted on a missile. They have to convert the uranium of arms degree, which is a gas, into a metal sphere. They have to surround that sphere with high precision explosives that have to detonate simultaneously in microseconds to compress the nucleus and start the chain reaction. And all this, in a package small and light enough to fit in the eyes of a missile and survive the launch. This is where we enter the field of almost total uncertainty. We know that this will investigated with the AMAD Plan, but its current progress is unknown. However, nobody knows it with certainty because intelligence on underground activities is very difficult to obtain. What we know with certainty. Despite decades of sanctions, sabotage, selective murders of its scientists and cyberbrains (like the famous Stuxnet, which destroyed uranium centrifuges), the Iranian nuclear program has not only survived, but has become stronger and more self -sufficient. Iran designs and produces its own advanced centrifuging. In fact, Israel’s main objective is to destroy the Fordow plant, that Iran built under a mountain to make it invulnerable to air attacks. In parallel, Iran has developed the largest and diverse ballistic missile program in the Middle East, and a fleet of trucks ready to shoot them. This resilience demonstrates that technical knowledge is deeply institutionalized in the regime, which is why Israel has eliminated those responsible for the nuclear program, as well as Iranian launches. At the same time, each Israeli attack can reinforce the conviction in Tehran that the pump is the only guarantee of survival, a fish that bites the tail, accelerated by Netanyahu’s rhetoric. They will go in the North Korean mirror or Pakistan. Beyond the rhetoric of the West, two countries offer key lessons about Iran. North Korea built its nuclear program to ensure the survival of the regime. Isolated and economically devastated, He saw the bomb as his only insurance policy against a overthrow imposed by the United States. The sanctions and pressure only reinforced their determination. Pakistan followed a strategic imperative. It sought to neutralize the military superiority of India. When India tried her bomb in 1974, the Pakistani bomb became a matter of national survival. Iran is a hybrid and more complex case. Share the survival … Read more

Believing that the healthy lasts less is changing how we eat (and how much we waste)

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Today, knowing how much a food really lasts has become almost a mystery. How much does a pepper in the fridge endure? Why does that apple have been in the fruitman for a week and nobody eats it? Have you spoiled or simply believe it? This confusion could be causing something else, an unnecessary increase in food waste. Short. Many foods come with labels such as “consuming preferably before”, “expiration date”, or even “packaged the …”, which has always been interpreted as a deadline for food security. However, According to EFSA (European Food Security Agency), this type of labeling does not mean that food is not safe after that date, but could lose quality, not security. There is a study behind. Between 2018 and 2024, more than 3,500 consumers from the United States, Canada, the United Kingdom and South Korea participated in an academic study in eight parts, Published in the Journal of Marketing Research. The objective of research was to understand how the perception of “healthy foods” affects their management and consumption. In one of the experiments, scientists asked participants to classify six products (cereals, snack bars, protein bars, yogurt, cookies and fried potatoes) in two categories: those who considered healthier and those who believed they would expire faster. The majority assumed that the food considered “healthier” were the ones who thought they would spoil before. Jeehye Christine Kim, professor at the University of Virginia and co -author of the study, explained it as follows: “This is due to the lack of knowledge about the deterioration of food. Consumers apply what they know about fresh fruits and vegetables to packaged foods, even when it is not logical to do it.” But there is something else. Research has shown that consumers were more likely to throw healthy food as their expiration date approached than to discard less healthy products in the same situation. However, researchers have given him a name: Heuristic Health. An automatic assumption that leads to think that, if a food is healthy, it must also be more perishable. That belief is born from the real experience with fresh fruits and vegetables – which are spoiled quickly – and is erroneously applied to packaged products such as yogurts or bars. To that is added another factor: the fear of making mistakes. As we do not always know how to identify whether a food is still safe or not, and since the labels do not help, we prefer to discard it “just in case.” But that “just in case” has a cost: more wasted food, many times without need. A search to waste less. Researchers suggest that one of the keys to solve this problem is on labeling. As explained by Brent McFerran, professor at Simon Fraser University and Co -author of the study, to The Wall Street Journalboth the food industry and governments must act, since “many perfectly healthy and safe foods for consumption usually throw themselves in the trash due to ignorance of how long they can be consumed without danger.” For its part, EFSA promotes information campaigns so that consumers learn the difference between expiration labels and preferred consumption, and drives manufacturers to improve the clarity of their containers. Beyond choosing healthy. Eating healthy should not mean throwing more food. But while confusion persists on what a date printed in a container really means, thousands of perfectly edible products will continue to end in the trash every day. Understanding what the labels mean, demanding clarity and rethinking our perceptions can have a real impact, not only on our health, but also on the planet. Because choosing healthy should also include taking care of what is not wasted. Image | Dean Hochman Xataka | A squirrel could cross Spain jumping from supermarket in supermarket: how we have obsessed with the purchase

We have been reading about the danger of arsenic in rice for years. So much that we run the risk of not believing it in the worst possible time

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Arsenic is one of the best known toxic elements. The fact that traces of this element can be found in the rice we consume sounds more alarming than it really is: today only very high consumption of this food could involve health risks. The problem is that this can change in the future. Growing concentrations. A new study has pointed out that the increase in temperatures and carbon dioxide concentrations (CO2) in the atmosphere can favor the absorption of arsenic in rice crops. This would translate into a greater presence of the element in the dishes elaborated from this cereal. A change whose impact could be significant around 2050. This increase in arsenic concentration could especially affect the population in Asia, where rice represents a higher portion of the food consumed. “Our results suggest that this increase in arsenic levels could significantly raise the incidence of heart disease, diabetes, and (cause) other non -carcinogenic effects,” he said In a press release Lewis Ziskka, co -author of the study. The risk of arsenic. Arsenic is considered a heavy metal despite chemically belonging to the semimetal group. He Risk level which implies its presence depends on several factors, for example on the fact of the molecular structure in which it occurs (its organic structures are less dangerous than the inorganic ones). And, of course, it depends on the dose. The risk posed by this element has to do with its accumulation in our body. Its presence can lead to problems in development among the youngest, and in adults it has been related to skin disorders, bladder and cancer of lung. 28 Rice varieties. The team responsible for the study analyzed the effects on the rice of an average increase of 2º Celsius at the temperature and the associated increase of atmospheric CO2. Did it in 28 varieties of this cereal, modeling the evolution of its inorganic arsenic content over 10 years. From there, the team estimated the health impacts that this accumulation could produce in the populations of seven Asian countries around 2050. The result: a drastic increase in cancer cases and especially the cases of bladder cancer. Among the countries studied, China would stand out, which could see more than 13 million new cases of cancer associated with arsenic exposure. The details of the study were published In an article In the magazine The Lancet Planetary Health. Not everything is lost. In its study, the team raises some possible adaptation measures dedicated to reducing the future impacts of this problem. The team suggests hybridar varieties of plants to favor those that absorb less, introduce improvements in soil management in rice fields, and improve food processing practices. They also propose consumer -centered measures: education and minitor, they explain, they could play an important role in reducing the impacts of this growing presence of arsenic. The occasional alerts we receive regarding arsenic levels in rice could make this more difficult, by turning this problem into a “Pedro and the Wolf story”: a non -existent problem that we pay attention today could become a real problem that we ignore in the future. In Xataka | What is really happening with white rice (and to what extent should we worry) Image | Shayan Ghiasvand

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