Prediction of when the Universe will end

 Physicists predict the universe will end in a big crunch              

A Cornell physicist proposes that the universe is only halfway through its 33-billion-year lifespan, and will one day reverse course. Based on new dark-energy data, Henry Tye’s model suggests the cosmos will stop expanding in about 11 billion years and ultimately collapse into a “big crunch,” ending in a single point. If recent discoveries that dark energy is evolving hold any water, our Universe will collapse under its own gravity on a finite timeline, new calculations suggest. Based on several recent dark energy results, a new model finds that the Universe has a lifespan of just 33.3 billion years. Since we are now 13.8 billion years after the Big Bang, this suggests that we have a smidge less than 20 billion years left. Dark-energy evidence suggests the universe will end in a “big crunch” roughly 20 billion years from now.

The findings suggest that the cosmos will continue expanding for roughly another 11 billion years before reversing course, contracting back into a single point in a dramatic “big crunch.” For another 11 billion years, the Universe will continue to expand, before coming to a halt and reversing direction, collapsing down to the hypothetical Big Crunch, say physicists Hoang Nhan Luu of Donostia International Physics Centre in Spain, Yu-Cheng Qiu of Shanghai Jiao Tong University in China and corresponding author Henry Tye of Cornell University in the US.  Most precise measure of Dark energy confirms universe won't tear apart. "For the last 20 years, people believed that the cosmological constant is positive, and the universe will expand forever," Tye says. "The new data seem to indicate that the cosmological constant is negative, and that the Universe will end in a Big Crunch."

Henry Tye, the Horace White Professor of Physics Emeritus in the College of Arts and Sciences, arrived at this conclusion after updating a theoretical model that incorporates the “cosmological constant,” a concept first proposed by Albert Einstein more than a century ago and widely used by modern cosmologists to describe the universe’s expansion. The cosmological constant Tye refers to is λ, introduced by Albert Einstein in his theory of general relativity to describe the expansion of the Universe. If the value of λ is positive, then it acts as a force that constantly pushes outward, contributing to the Universe's expansion. If λ is negative, it behaves like a constant pull that never fades, and can eventually stop and reverse the expansion. Recent observations hint that dark energy may be changing over time. In the new model, the authors' best-fit goes hand-in-hand with a small negative λ, though current data don't rule out that λ equals 0. Since a negative λ pulls inward, it would hinder rather than aid the Universe's expansion. Tye is the corresponding author of a recent study about the findings published in the Journal of Cosmology and Astroparticle Physics. 

The universe, now about 13.8 billion years old, continues to expand outward. According to Tye, the future depends on the value of the cosmological constant: if it is positive, expansion will continue indefinitely; if it is negative, the universe will eventually reach a maximum size before reversing direction and collapsing entirely. His calculations support the latter scenario, a future in which the cosmos contracts to zero, marking the ultimate end of space and time. Nevertheless, the Universe is indeed expanding, according to an overwhelming majority of evidence. But we can get to the observed behaviour of the Universe if we combine a small negative λ with an ultralight axion field which behaves like dark energy today. Axions are, we think, ultra-light particles that can also be thought of as a smooth, ghostly field throughout space, first proposed decades ago as a potential solution to some other problems in particle physics. In their new analysis, Tye and his colleagues describe the axion as a force which gives the Universe a gentle push outwards in the beginning, but that slowly eases over time.

“This big crunch defines the end of the universe,” Tye wrote. He determined from the model that the big crunch will happen about 20 billion years from now. The big news this year is the reports by the Dark Energy Survey (DES) in Chile and the Dark Energy Spectroscopic Instrument (DESI) in Arizona this spring. Tye said these two observatories, one in the southern hemisphere and one in the northern, are in good accord with each other. The whole idea of the dark energy survey of these two groups is to see whether dark energy, 68% of the mass and energy in the universe, really comes from a pure cosmological constant. They found that the universe is not just dominated by a cosmological constant, dark energy. The dark energy actually has something else going on. At the current time, the influence of the axion still reigns, pushing the Universe outward at an accelerating rate as gravity weakens between bodies stretching farther and farther apart, so the Universe is still accelerating today in this scenario.

Tye and his collaborators proposed in the paper a hypothetical particle of very low mass which behaved like a cosmological constant early in the life of the universe, but does not anymore. This simple model fits the data well but tips the underlying cosmological constant into negative territory. “People have said before that if the cosmological constant is negative, then the universe will collapse eventually. That’s not new,” Tye said. “However, here the model tells you when the universe collapses and how it collapses.” In about 11 billion years, the axion's push will weaken sufficiently that the pull of negative λ will take over, bringing the Universe's outward expansion to a standstill at a maximum size of about 1.7 times its current size. Then, the Universe will start to contract again, whooshing down to a Big Crunch in just 8 billion years. It's a bit like riding a bike up a hill, with a tailwind pushing you: going up, as the tailwind eases, your ascent slows, then gently stalls at the crest before you head down the steeper side, gaining speed as you go.

There are more observations to come, Tye said. Hundreds of scientists are measuring dark energy by observing millions of galaxies and the distance between galaxies, gathering even more accurate data to feed into the model. DESI will continue observations for another year, and observations are on-going or will begin soon at several others, including the Zwicky Transient Facility in San Diego; the European Euclid space telescope; NASA’s recently launched SPHEREx mission; and the Vera C. Rubin Observatory (named after Vera Rubin, M.S. ’51). According to the paper, the 'downhill' contraction is quicker because the axion's kinetic energy takes over, and rising densities strengthen gravity's pull, making the crunching phase shorter than the expansion phase. The Big Crunch is like the opposite of the Big Bang, where all the matter in the Universe smooshes back together into one infinitely dense singularity. It's important to note that this is far from a certainty, not a prediction, but one possible future if the recent hints can be validated. A lot more data-crunching will be needed to determine whether dark energy is, indeed, evolving. In addition, we still don't know what dark energy is; it may not be axions or axion-like particles at all, but something entirely different.

Nevertheless, the paper provides one potential answer to one of cosmology's biggest questions. "For any life, you want to know how life begins and how life ends – the end points," Tye says. "For our Universe, it's also interesting to know, does it have a beginning? In the 1960s, we learned that it has a beginning. Then the next question is, 'Does it have an end?' For many years, many people thought it would just go on forever. It's good to know that, if the data holds up, the Universe will have an end." Tye finds it encouraging that the lifespan of the universe can be quantitatively determined. Knowing both the beginning and the end of the universe provides a greater understanding of the universe, the goal of cosmology.

Muhammad (Peace be upon him) Names

 

ALLAH Names

 

Most efficient fibre-optic deployment system

 First jet-propelled fibre-optic system with 25,000-ft deployment in less than an hour 

WellSense, a specialist in fibre optic well diagnostics, has developed a ground breaking, single-use, jet-propelled and battery powered well conveyance technology, which is able to rapidly deploy bare fibre into highly deviated wells. The conveyance system has been designed to improve the speed, quality, cost and efficiency of diagnostic surveys in horizontal wells. FliCS uses magnetic launch, battery power and jet-drive thrust to deploy fibre for real-time temperature, strain and acoustic sensing. The conveyance system has been designed to improve the speed, quality, cost and efficiency of diagnostic surveys in horizontal wells. AUK company has successfully tested an advanced diagnostic technology in the US that offers faster, safer and more efficient fibre-optic deployment.

WellSense’s Fibre Line Intervention Conveyance System (FliCS) uses jet propulsion and battery power to deploy bare fibre rapidly into complex, highly deviated wells. Tested in the Permian Basin in August 2025, the system delivered a 25,000-ft Fli probe into a 19,000-ft horizontal well about ten times faster than conventional pump-down methods. WellSense successfully completed a technology field trial, where the FiberLine Intervention Conveyance System (FliCS) deployed bare fibre into a 19,000 foot uncompleted well in the Permian Basin for cross well strain monitoring. The deployment took just 50 minutes. The trial was delivered for a major international operator which provided support for early technology development and, witnessing the results, the operator has confirmed its intention to redeploy the technology in four further projects over the next three months.

“FliCS will provide well operators a cost-effective, low-risk well surveillance solution for horizontal wells for the first time,” said Annabel Green, CEO at WellSense. Earlier, Penn State researchers proposed storing renewable energy in depleted oil and gas wells using compressed air, reducing costs and addressing environmental concerns about abandoned wells. FliCS has been developed at WellSense’s UK headquarters and R&D hub in Aberdeen, by Dan Purkis, the company’s founder, technology director and respected industry innovator. The new well access solution introduces the ability to deploy Fli into horizontal wells to acquire distributed acoustic sensing and distributed temperature sensing data across the reservoir. FliCS is a jet-propelled, battery-powered platform representing a major advance in fibre-optic well diagnostics. The lightweight conveyance system is designed to rapidly deploy bare optical fibre into complex, highly deviated or horizontal wells without requiring conventional pump-down or tractor-assisted operations. FliCS is triggered by a magnetic switch and powered by small on-board batteries at launch. Its jet-drive propulsion system, when deployed, creates thrust by accelerating well fluids via an impeller unit, which moves the probe through the wellbore.

Annabel Green, CEO at WellSense, said, FliCS will provide well operators a cost-effective, low risk well surveillance solution for horizontal wells for the first time. While it will have many applications in well integrity, it also enables a major expansion of injection profiling capabilities. This has global application, providing performance data to enable water injection to be optimised for effective pressure support and oil displacement. The apparatus de-spools optical fibre as it travels, allowing high-resolution distributed fibre-optic sensing (DFOS) to monitor temperature, strain and acoustic data in real time along the well’s length. The prototype machine showed remarkable speed, deploying up to 25,000 feet of fibre in little over an hour, which is around 10 times quicker than the average of 35 feet per minute for traditional tractor conveyance methods. FliCS uses less fluid and operates at about 350 feet/ minute, drastically reducing operating time and expense.

In addition to speed and efficiency, FliCS enhances safety and operational flexibility. The system’s lightweight, non-metallic components pose negligible risk to future well interventions, as they can be left safely in the toe of the well or pushed to the bottom if retrieval is unnecessary. “While it will have many applications in well integrity, it also enables a major expansion of injection profiling capabilities. This has global application, providing performance data to optimize water injection for effective pressure support and oil displacement,” said Green. “For our key clients in the Middle East, FliCS will provide valuable diagnostics for matrix acid stimulation. This approach is widely used to improve carbonate rock matrix permeability and flow channels, so improved knowledge of fluid placement can greatly enhance treatment and directly improve well performance.

Wellsense highlights that its Fli solutions are designed for versatility, supporting a broad spectrum of well applications such as production optimization, well integrity evaluation, stimulation monitoring and abandonment planning. The Fli Dynamic De-Spool can be deployed into live wells without the need for a rig or heavy intervention systems, significantly reducing operational complexity and cost. Their low-impact deployment method suits them particularly for remote and environmentally sensitive sites, where conventional intervention equipment may be impractical or disruptive. The probe is lowered manually or through a simple hydraulic release mechanism, allowing for rapid mobilization and minimal interference with on-going operations. “We’re incredibly excited by the market growth opportunity this unique solution presents for us, and by the efficiency, diagnostic and carbon reduction benefits it’s set to provide the wider industry. Our next step is to deliver our first, multi-unit, prototype order while developing a slimmer model for deployment through smaller tubing. We’ll be maturing the technology ready for commercial launch early next year but actively engaging with customers at ADIPEC and beyond to discuss opportunities” said Green. 

In practical deployment, the system’s simplicity enables a single engineer to complete the entire process in under an hour. Data acquisition begins immediately once the fibre enters the well, ensuring real-time insights into well performance. Depending on the depth and conditions of the well, most surveys are completed within a single shift. According to the firm, the streamlined approach enhances efficiency, reduces downtime, and delivers high-quality data faster, making Fli Technology an ideal solution for operators seeking safe, reliable and cost-effective well monitoring and diagnostic capabilities across various environments. The pioneering FliCS conveyance system from WellSense uses lightweight battery powered jet propulsion which is triggered by a magnetic switch at launch. Jet-drive technology accelerates well fluids through an impellor sub to generate thrust while the probe de-spools optical fibre along the well to enable highly sensitive distributed fibre optic sensing data to be acquired. The prototype model deploys 25,000 feet of fibre in little over an hour, travelling around 350 ft/ min. versus ~35 ft./ min. for a conventional tractor conveyance. The risk to future operations is negligible as the lightweight components can be left in the toe of the well or pushed to the bottom.

Muhammad (Peace be upon him) Names