Tag Archives: phase

Research Indicates Our Universe Is Already Entering a Slowdown Phase

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A recent study from Yonsei University in Seoul, South Korea, challenges the previously accepted notion that dark energy is causing the accelerated movement of distant galaxies away from us. The researchers found no evidence supporting the idea that the universe is currently accelerating. If validated, this finding could significantly alter our understanding of dark energy, address the “Hubble strain,” and provide insights into the universe’s past and future.

The expansion of the universe may be slowing down, not accelerating. Image credit: M. Weiss / Harvard-Smithsonian Center for Astrophysics.

For over three decades, astronomers have generally accepted that the universe is expanding at an increasing rate due to a hidden force dubbed dark energy, which functions as a sort of anti-gravity.

This conclusion, derived from distance measurements of far-off galaxies using Type Ia supernovae, earned the Nobel Prize in Physics in 2011.

However, Professor Yongwook Lee of Yonsei University and his team have introduced new evidence suggesting that Type Ia supernovae, once thought to be the universe’s “standard candle,” are significantly affected by the age of their progenitor stars.

“Our findings indicate that the universe is currently in a phase of decelerating expansion, and that dark energy is evolving at a much faster rate than previously assumed,” stated Professor Lee.

“If verified, these outcomes would signify the most substantial shift in cosmology since the identification of dark energy 27 years ago.”

Even after adjusting for brightness, supernovae from younger star populations seem systematically dimmer, while those from older populations appear brighter.

Utilizing a more extensive sample of 300 host galaxies, the researchers validated these findings with remarkable significance (99.999% confidence), indicating that the dimming of distant supernovae is influenced not only by cosmological factors but also by stellar astrophysical characteristics.

After correcting for this systematic bias, the supernova data no longer aligned with the classic ΛCDM cosmology model that includes a cosmological constant.

Instead, it aligns more closely with a new model backed by the Dark Energy Spectroscopy Instrument (DESI) project, based on Baryon Acoustic Oscillations (BAO) and Cosmic Microwave Background (CMB) data.

Both the adjusted supernova data and the results from BAO+CMB demonstrate that dark energy diminishes and evolves significantly over time.

Importantly, when the corrected supernova data were integrated with BAO and CMB findings, the traditional ΛCDM model was decisively ruled out.

Most notably, this comprehensive analysis reveals that the universe is not accelerating as much as once believed, but has already transitioned into a state of slowing expansion.

“The DESI project has yielded significant results by merging unadjusted supernova data with baryon acoustic vibration measurements, concluding that while the universe will decelerate in the future, it is still accelerating at present,” remarked Professor Lee.

“Conversely, our analysis, which incorporates an age-bias correction, indicates that the universe is already entering a slowing phase today.”

“Surprisingly, this aligns with predictions made independently from BAO analyses, which has yet to receive much attention.”

To further validate their findings, the researchers are now conducting an evolution-free test using only supernovae from young, contemporaneous host galaxies across the entire redshift range.

Initial results already support their primary conclusion.

“With the Vera C. Rubin Observatory set to discover more than 20,000 new supernova host galaxies within the next five years, accurate age measurements will provide a more robust and conclusive examination of supernova cosmology,” stated Yonsei University professor Chul Chung.

The team’s paper published today in Royal Astronomical Society Monthly Notices.

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Song Joon Hyuk et al. 2025. Strong founder age bias in supernova cosmology – II. Alignment of DESI BAO with signs of a non-accelerating universe. MNRAS 544 (1): 975-987; doi: 10.1093/mnras/staf1685

Source: www.sci.news

Unveiling a New Ice Phase: Ice XXI

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Researchers have shown that hypercompressed water can undergo various freeze-thaw processes to convert into ice VI at room temperature, facilitated by a previously unidentified metastable ice form known as ice XXI.

Small ice crystals XXI formed through a nucleation and slow melting process. Image credit: Lee et al., doi: 10.1038/s41563-025-02364-x.

Water consists of only two elements, yet it has numerous polymorphs ranging from Ice Ih to Ice XX, along with four amorphous phases.

The exploration of formation and migration pathways for various water phases has captivated scientists for a century, especially in high-pressure physics and the quest for extraterrestrial life on icy moons.

“Water exhibits remarkable complexity in its solid forms,” stated Dr. Lee Geun-woo from the Korea Institute of Standards and Science and the National University of Science and Technology.

“Most phases are typically found under conditions of high pressure and low temperature.”

“When water is compressed rapidly, it can remain in a liquid state even under high pressures where it would normally crystallize into ice VI.”

“Ice VI is particularly fascinating, as it is believed to exist within icy moons like Titan and Ganymede.”

“Its highly distorted structure may facilitate intricate transition pathways that lead to metastable ice forms.”

“Most ice variants can only be observed under extreme conditions; hence, we utilized a diamond anvil cell to create these high-pressure conditions.”

“In this setup, the water sample is positioned between two diamonds, which can withstand and apply immense pressure.”

“The water was subjected to pressures as high as 2 gigapascals, roughly 20,000 times greater than typical atmospheric pressure.”

“This allows for ice formation even at room temperature, with molecules packed more tightly than in conventional ice.”

To examine ice formation under varied pressure conditions, researchers initially produced high pressures of 2 gigapascals in just 10 milliseconds.

They then took 1 second to release the anvil cell and repeated this procedure.

During these cycles, the scientists utilized Europe’s XFEL’s X-ray flashes to capture images of the sample every microsecond.

With extremely high X-ray pulse rates, they could even create videos illustrating the formation of ice structures.

Using PETRA III’s P02.2 beamline, the researchers confirmed that ice XXI possesses a tetragonal crystal structure composed of unusually large repeating units known as a unit cell.

“The unique X-ray pulses from Europe’s XFEL revealed multiple crystallization pathways in rapidly compressed and depressurized water over 1,000 times using a dynamic diamond anvil cell,” Dr. Lee explained.

“In this specialized pressure cell, the sample is squeezed between the tips of two opposing diamond anvils, following a defined pressure trajectory,” said Dr. Cornelius Strom from the Deutsche Electron Synchrotron.

“The crystallization structure of liquid water is influenced by the degree of supercompression,” added Dr. Lee.

“Our results hint at the potential existence of more high-temperature metastable ice phases and the related transition pathways, offering new insights into the compositions of icy satellites,” remarked Dr. Rachel Husband, also from the Deutsche Electron Synchrotron.

These findings were published in a magazine on October 10th in Nature Materials.

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YH. Lee et al. Multiple freeze-thaw paths of dense ice through the ice XXI phase at room temperature. Nat. Mater. published online on October 10, 2025. doi: 10.1038/s41563-025-02364-x

Source: www.sci.news

A breakthrough in quantum simulation: Discovery of the long sought-after phase change

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Ion traps can control atoms for quantum experiments

Y. Colomb/National Institute of Standards and Technology/Scientific Photo Library

After decades of investigation, researchers observed a series of atoms undergoing a one-dimensional phase change. This was so elusive that it could only happen in a quantum simulator.

“There is only one motive [for our experiment] I'm trying to really understand basic physics. “We're just trying to understand the fundamental states that matter can be in,” he says. alexander shuckardt at the University of Maryland.

He and his colleagues used electromagnetic fields to arrange 23 ions of the element ytterbium in a line, forming a nearly one-dimensional chain. The device can be used for quantum computing, but in this case the researchers used the chain as a simulator instead.

In it, they built a 1D ytterbium magnet one atom at a time. Previous calculations predicted that this type of magnet would become unmagnetized when warmed, thanks to quantum effects. However, no experiments have achieved this phase transition in the past.

One reason for the difficulty is that systems such as quantum computers and simulators typically only work properly when they are very cold. So heating them to cause a phase transition can cause them to malfunction, Schuckert says.

To get around this, he and his colleagues tuned the initial quantum state of the atoms so that over time, the collective state of the 1D magnet changes as if the temperature were increased. This revealed a phase transition that had never been seen before.

The result is very unusual, he says, because chains of atoms are generally not supposed to undergo phase transitions. Mohammad Maghrebi at Michigan State University. The researchers were able to manipulate it precisely because each ion could interact with other ions over large distances, even if they weren't in contact. This caused the entire line to engage in abnormal collective behavior.

Because their simulator allows for such exotic states of matter, it could be used to study theoretical systems that are extremely rare or may not exist in nature, Maghrebi said. say.

Schuckert suggests that quantum simulators could also help explain the strange electrical or magnetic behavior that some materials exhibit in the real world. But for that to happen, these devices will have to be able to reach higher temperatures than they currently do. Currently, researchers can only create models at extremely low temperatures, but within five years it may be possible to simulate even higher temperatures, he says.

And if the simulator could be made larger, for example by arranging ions in two-dimensional arrays, many more existing theoretical systems could be studied, he says. andrea trombettoni at the University of Trieste, Italy. “This would suggest new physics to explore,” he says.

Source: www.newscientist.com

Chemists show the existence of sulfurous acid in the gas phase in normal atmospheric conditions

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Chemists at the Leibniz Institute for Tropospheric Research have discovered that sulfurous acid (H2So3), once formed in the gas phase, is kinetically stable enough to allow its characterization and subsequent reactions.

In the gas phase, sulfurous acid, once formed, exhibits some kinetic stability with a lifetime of at least 1 second in atmospheric water vapor conditions. Image courtesy of Berndt others., doi:10.1002/anie.202405572.

Sulfurous acid Having formula H2So3 The molecular weight is 82.075 g/mol.

This molecule, also known as sulfuric acid(IV) or thioic acid, is a difficult-to-reach acid that has never before been observed in aqueous solution.

However, sulfite Detected It was discovered in the gas phase in 1988 by dissociative ionization of diethyl sulfite.

“The only experimental detection of sulfurous acid to date was achieved in 1988 by the team of Helmut Schwarz at the Technical University of Berlin using in situ generation with a mass spectrometer,” said Dr. Torsten Berndt of the Leibniz Institute for Tropospheric Research and colleagues.

“Under vacuum conditions, we estimated an extremely short lifetime of more than 10 microseconds.”

“Theoretical calculations show that H2So3 As a possible reaction product of the gas-phase reaction of OH radicals with dimethyl sulfide (DMS), which are produced from ozone and water molecules in the troposphere primarily in the presence of ultraviolet light.”

“DMS is produced primarily by biological processes in the ocean and is the largest source of biogenic sulfur in the atmosphere, producing approximately 30 million tonnes per year.”

The researchers experimentally investigated possible reaction pathways to H.2So3 It starts with DMS.

Formation of H2So3 Its formation in the gas phase was clearly demonstrated in a flow reactor under atmospheric conditions.

“Under our experimental conditions, sulfurous acid remained stable for 30 seconds, regardless of humidity,” the researchers said.

“With the existing experimental setup, longer residence times have not yet been explored.”

“Therefore, H2So3 It may persist in the atmosphere long enough to affect chemical reactions.”

“The observed yields were somewhat higher than theoretically expected.”

According to related model simulations, about 8 million tons of H2So3 They form every year all over the world.

“In this pathway, the mass of H increases by about 200 times.2So3 Sulfuric acid (H2So4“It produces carbon dioxide (CO2) from dimethyl sulfide in the atmosphere,” said Dr Andreas Tilgner and Dr Eric Hofmann from the Leibniz Institute for Tropospheric Research.

“The new results may contribute to a better understanding of the atmospheric sulfur cycle.”

Team paper Published in the journal Applied Chemistry.

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Torsten Berndt others2024. Gas-phase production of sulfurous acid (H)2So3) floats in the atmosphere. Applied Chemistry 63(30):e202405572;doi:10.1002/anie.202405572

Source: www.sci.news

Third spacecraft launch successfully reaches space but fails to return during re-entry phase

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SpaceX Starship takes off on March 14th

space x

SpaceX’s third and most ambitious Starship test flight appears to have been at least partially successful today, as it reached space, conducted fuel transfer tests, and traveled farther and faster than ever before. It looked like. However, the spacecraft failed to make its planned landing and appears to have either self-destructed or burned up in Earth’s atmosphere.

After launching from SpaceX’s property in Boca Chica, Texas, the first and second stages separate cleanly and the first stage (the booster that lifts the craft during the first part of its journey) descends to land at sea. started. SpaceX ultimately intends to recover and reuse both stages, but these early test flights are slated for a safer, easier water landing for both.

The first stage steered itself downhill, but seemed to struggle to slow its fall as intended and appeared to hit the sea at breakneck speed.

The second stage reached an altitude of approximately 230 kilometers and successfully opened and closed the payload door as a test. It was also possible to swap fuel from one tank to another, an experimental first step towards eventually refueling from one spacecraft to another. This is essential for long-range missions.

However, during reentry, the spacecraft reached such high temperatures that live video showed glowing plasma around the surface, and both video and telemetry data were lost.

The spacecraft would attempt to reignite the Raptor engines, something never before done in space, as it entered the atmosphere in a controlled manner at about 27,000 kilometers per hour. However, the relighting portion of this mission was omitted by the company, and the spacecraft was subsequently lost.

A view of SpaceX’s Starship taken nine minutes into the mission.

space x

US Federal Aviation Administration permission granted In preparation for the test flight on March 13th, the day before the scheduled launch date, tweeted SpaceX said it “met all safety, environmental, policy and financial responsibility requirements.”

starship It is the most powerful rocket ever made. The 121-meter-long ship consists of her two stages, a booster and a spacecraft, both of which are designed to be reusable, keeping costs down and allowing quick turnaround between flights. Masu.

Starship heated up during re-entry into Earth’s atmosphere after a flight of approximately 47 minutes, leading to the loss of the spacecraft.

space x

Today’s announcement marks the company’s third Starship announcement. In the first test in April last year, the first and second stages exploded before they separated, and in the test in November, the upper second stage reached space, but, which self-destructed when it stopped transmitting data, following the explosion of the first stage. Immediately after separation.

The ultimate goal of this project is to land humans on the moon and later on Mars.

topic:

Source: www.newscientist.com

Next Phase of Human Clinical Trials for Revolutionary Sepsis Treatment Commences

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Scientists have developed a promising treatment for sepsis, and clinical trials using sodium ascorbate, a vitamin C preparation, have shown effective results. The treatment has progressed into extensive clinical trials across Australia and demonstrated significant improvements in sepsis patients, including improved kidney function and reduced dependence on other drugs. This breakthrough, the result of decades of research, brings hope to a disease that is the leading cause of death in intensive care units around the world.

Flory Institute researchers, in collaboration with hospital intensivists, have demonstrated that sodium ascorbate, a pH-balanced formulation of vitamin C, is effective in treating sepsis.

Researchers at the Florey Institute have demonstrated that the formulation they have developed reduces deadly sepsis, and the next phase of clinical trials is set to begin across Australia next month.

Promising results from early clinical trial conducted at Melbourne’s Austin Hospital published in journal Critical carehave shown that sodium ascorbate, a pH-balanced formulation of vitamin C, is effective in treating sepsis.

Lead researcher Associate Professor Yugish Lankadeva said sepsis is notoriously difficult to treat and is often fatal.

LR Florey Professor Clive May, Austin Health Intensivist Professor Rinaldo Bellomo and Florey Associate Professor Yugish Rankadeva discovered that sodium ascorbate can be used to treat sepsis.Credit: Flory

Challenges in sepsis treatment

“Sepsis accounts for 35 to 50 percent of all hospital deaths. It is when the immune system is unable to fight the underlying infection, causing a life-threatening drop in blood pressure, multiple organ failure, and death. ,” said Associate Professor Lankadeva. In our clinical trial at Austin Hospital, sodium ascorbate was administered into patients’ bloodstreams, resulting in promising improvements in multiple organs. ”

Associate Professor Lankadeva, Florey’s research director for Systems Neuroscience, said of the next steps: $4.9 million government-funded research project Delivered in intensive care units in Adelaide, Melbourne, Perth, Brisbane, Alice Springs and Sydney.

“We will recruit 300 adult sepsis patients who will receive either our formulation or a placebo in addition to their usual hospital care. These results will provide additional data to determine the efficacy of the formulation. It will help in collection,” said Associate Professor Lankadeva.

Flory scientists have created a special formulation of sodium ascorbate to treat sepsis.Credit: Flory

Insights into previous trials

Professor Rinaldo Bellomo, director of intensive care research at Austin Hospital, said the first part of the trial at his department involved 30 adult sepsis patients between October 2020 and November 2022.

While in intensive care in the hospital, half of the patients were randomly assigned to receive sodium ascorbate, and the other half received a placebo.

This study found that patients with sepsis treated with sodium ascorbate:

  • Signs that more urine is produced and kidney function has improved
  • Less need for noradrenaline, a drug used clinically to restore blood pressure
  • He showed signs of improved function in multiple organs.

“Sepsis is the number one cause of death in intensive care units in Australia and around the world,” Professor Bellomo said. “In many cases, the disease progresses so rapidly that by the time patients reach us, they are already seriously ill. It will be a huge change.”

Decades of research bear fruit

Professor Clive May, Florey Senior Research Fellow on the project, has been researching how sepsis causes organ failure, particularly damage to the brain and kidneys, for more than 20 years.

“By showing decreased oxygen levels in the tissues of sepsis, we found that sodium ascorbate was a possible treatment.

“We have seen dramatic results in preclinical studies, where extremely high doses of sodium ascorbate caused complete recovery within just three hours with no side effects. It’s heartening to see that it’s paying off and bringing treatments into the hands of patients,” said Professor Clive May.

Surviving sepsis: The patient’s perspective

Longtime Flory staffer Brett Purcell serves as the consumer representative for the MEGASCORES research program, providing a valuable perspective from sepsis survivors.

“In 2011 I was taken to the hospital by ambulance with high fever and delirium. I was suffering from the early stages of sepsis. My condition gradually worsened and I was transferred to a larger hospital after 12 days. By that time My heart was severely infected and I was in septic shock. Six months ago I had a successful aortic valve replacement. Unfortunately the valve was infected.

“The surgical team repaired the damage in a six-hour operation, but my condition deteriorated to critical condition. I was told it would be an hour. It was the good decision-making of the surgical team and ICU intensivist that saved me. I was put on life support with an ECMO machine and dialysis, and my symptoms rapidly worsened. Improved.

“After almost eight weeks in the hospital, I’m home. I’m really lucky to be alive and hope this new research using sodium ascorbate is less invasive, faster, and extremely effective in fighting sepsis.” We hope to provide hospitals with a new and effective life-saving tool.”

Reference: “Ultra-dose sodium ascorbate: pilot, single-dose, physiological effects, double-blind, randomized, controlled trial” Fumitaka Yanase, Sofia Spano, Akinori Maeda, Anis Chaba, Thummaporn Naorungroj, Connie Pei Chen Ow , Yugeesh R. Rankadeva, Clive N. May, Ashenafi H. Betley, Darius JR Lane, Glenn M. Eastwood, Mark P. Plummer, Rinaldo Bellomo, October 12, 2023. Critical care.
DOI: 10.1186/s13054-023-04644-x

Source: scitechdaily.com

NASA’s Exciting Test Phase for Dream Chaser

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NASA and Sierra Space are making progress toward the company’s Dream Chaser spacecraft’s maiden flight to the International Space Station. The unmanned cargo spaceplane is scheduled to begin demonstration missions to orbital complexes in 2024 as part of NASA’s commercial resupply services. Credit: Sierra Space

NASA and Sierra Space are testing the Dream Chaser spacecraft at the Neil Armstrong Test Facility, with a focus on environmental simulation for future ISS missions. After testing, the spacecraft will head to Kennedy Space Center for launch in 2024.

NASA and Sierra Space are preparing for the maiden flight of their Dream Chaser spacecraft. international space station. Dream Chaser and its accompanying cargo module “Shooting Star” NASA’s Neil Armstrong Test Facility It will fly in Sandusky, Ohio, for environmental testing, scheduled to begin in mid-December ahead of its first flight scheduled for early 2024.

State-of-the-art testing equipment

The Neil Armstrong Test Facility, part of NASA’s Glenn Research Center in Cleveland, has multiple test facilities including the Space Environment Complex and the Space Propulsion Facility, both of which will be home to Dream Chaser. The complex includes a mechanical vibration facility that exposes test articles to the harsh conditions of launch.

During Armstrong’s stay, the Dream Chaser winged spacecraft will be stacked atop the Shooting Star cargo module on a vibration table, experiencing vibrations similar to those experienced during liftoff or atmospheric re-entry.

NASA and Sierra Space are making progress toward the company’s Dream Chaser spacecraft’s maiden flight to the International Space Station. The unmanned cargo spaceplane is scheduled to begin demonstration missions to orbital complexes in 2024 as part of NASA’s commercial resupply services. Credit: Sierra Space/Shay Saldana

Rigorous space simulation

After vibration testing, Dream Chaser will be moved to the propulsion facility for thermal vacuum testing. Dream Chaser is placed in a vacuum and exposed to low ambient pressure, low background temperature, and simulated dynamic solar heating, simulating the environment the spacecraft will encounter during its mission. This facility is the only facility capable of testing full-scale upper stage rockets and rocket engines under simulated space conditions and conducting high-temperature fires.

After testing at Armstrong, Dream Chaser will be transported to NASA’s Kennedy Space Center in Florida for further launch preparations, and is currently scheduled to launch in the first half of 2024.

Source: scitechdaily.com