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Are scientists on the brink of discovering a mirror universe?
New experiments look to the interplay between neutrons and magnetic fields to observe our universal reflection.

- Science fiction has long speculated about parallel universes and what they may be like.
- Researchers have devised new experiments to look for how a mirror universe may be influencing our own.
- If such evidence is found, it could bring to light many of the universe's mysteries, such as the nature of dark matter.
In the original Star Trek episode "Mirror, Mirror," the crew of the Enterprise are accidentally transported to a parallel universe. Dubbed the Mirror Universe, its denizens are evil doppelgangers of the crew, complete with garish uniforms, Nazi-like salutes, and full, robust goatees.
Like many concepts first imagined in science fiction, the mirror universe may actually exist, albeit in a far less melodramatic form.
As reported by New Scientist, physicists are busy speculating about our universal reflection, and two experiments are currently underway to search out the empirical evidence. If proof of a mirror universe is found, it may help solve many of physics most intractable questions.
Searching for our own reflection
At the Oak Ridge National Laboratory's traveling science fair, participants can experience life as a ion and then a neutron in a neutron beam. Photo credit: Genevieve Martin / ORNL / Flickr
The first experiment profiled by New Scientist comes courtesy of physicist Leah Broussard and her team at the Oak Ridge National Laboratory in Tennessee. They have devised a simple method for detecting a mirror universe.
An apparatus will fire a beam of neutrons at a wall with varying magnetic fields on both sides. These neutrons can't penetrate the wall, yet the researchers have placed a device behind it that will scan the area for these very subatomic particles.
Why? If any neutrons manage to appear behind the wall, it will be strong evidence that they oscillated into mirror neutrons, skipped right on pass the wall because it existed in a different part of the universe, and then oscillated back in time to hit the detection device.
"Only the [neutrons] that can oscillate and then come back into our universe can be detected," Broussard told New Scientist. "When passing through a magnetic field, the oscillation probability increases."
Broussard and her team are looking at neutrons because of a quirk in their decay.
Inside a nucleus, neutrons are perfectly stable, but outside, they decay into a proton, an electron, and an antineutrino of the electron type. Here's the quirk: all free neutrons should decay at the same rate, but that rate changes depending on how scientists measure it.
The first way to measure the lifetime of free neutrons is to isolate them in a "bottle trap" and then count how many remain after a certain amount of time. The second way is to count the protons emerging from a neutron beam generated by a nuclear reactor. Yet, scientists get different rates of decay for each — 14 minutes 39 seconds for the former, 14 minutes 48 seconds for the latter.
A possible explanation for this discrepancy is a mirror universe. Neutrons may have dual citizenship in both universes. When they summer in our neighboring universe, any protons they emit are not detected and therefore not counted in our measurements. This could explain why we see less decay activity in the neutron beam.
Signals in magnetic fields
The second experiment profiled by New Scientist was developed by Klaus Kirch and his team at the Paul Scherrer Institute in Switzerland. This team applied magnetic fields of varying strengths to neutrons in a bottle trap.
The goal is to find the telltale signals of mirror magnetic fields. These would suggest neutrons oscillating between universes, potentially supporting any evidence found by Broussard and her team.
"The experimentalist's view is, if it doesn't look completely crazy, can it be tested?" Kirch told New Scientist. "I don't really believe the signals are there, and we have designed an experiment that can disprove them, and we'll see what comes out of it."
Kirch and his team have completed their experiment and are currently analyzing the data.
A mirror darkly

As Yuri Kamyshkov, a mirror matter researcher at the University of Tennessee and a collaborator with Broussard, noted: "The probability of finding anything is low, but it's a simple and inexpensive experiment." Despite the odds, he adds, a positive result would usher in a physics revolution.
A mirror universe could explain many of physics' unsolved mysterious, among them the question of dark matter. As Michio Kaku told Big Think in an interview:
"Dark matter is massive, it has gravity, but it's invisible. It has no interactions with light or the electromagnetic force. So, there is a theory that says that perhaps dark matter is nothing but matter, ordinary matter, in another dimension hovering right above us."
Of course, Kaku points out, this is one of many different theories about dark matter. String theorists think dark matter may be a higher octave of string vibration.
One reason the mirror universe idea is so appealing is the math. Some models suggest a mirror universe would have to have been much cooler than our own during its early evolution. This difference would have made it easier for particles to cross over, resulting in five mirror particles for every regular one. That's roughly the ratio of dark to normal matter.
Scientific models, in the end, must be backed by empirical evidence. We'll have to wait for the results of these and other experiments before determining the probability that a mirror universe exists — let alone if its beard game can match our own.
How New York's largest hospital system is predicting COVID-19 spikes
Northwell Health is using insights from website traffic to forecast COVID-19 hospitalizations two weeks in the future.
- The machine-learning algorithm works by analyzing the online behavior of visitors to the Northwell Health website and comparing that data to future COVID-19 hospitalizations.
- The tool, which uses anonymized data, has so far predicted hospitalizations with an accuracy rate of 80 percent.
- Machine-learning tools are helping health-care professionals worldwide better constrain and treat COVID-19.
The value of forecasting
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Credit: Northwell Health
<p>One unique benefit of forecasting COVID-19 hospitalizations is that it allows health systems to better prepare, manage and allocate resources. For example, if the tool forecasted a surge in COVID-19 hospitalizations in two weeks, Northwell Health could begin:</p><ul><li>Making space for an influx of patients</li><li>Moving personal protective equipment to where it's most needed</li><li>Strategically allocating staff during the predicted surge</li><li>Increasing the number of tests offered to asymptomatic patients</li></ul><p>The health-care field is increasingly using machine learning. It's already helping doctors develop <a href="https://care.diabetesjournals.org/content/early/2020/06/09/dc19-1870" target="_blank">personalized care plans for diabetes patients</a>, improving cancer screening techniques, and enabling mental health professionals to better predict which patients are at <a href="https://healthitanalytics.com/news/ehr-data-fuels-accurate-predictive-analytics-for-suicide-risk" target="_blank" rel="noopener noreferrer">elevated risk of suicide</a>, to name a few applications.</p><p>Health systems around the world have already begun exploring how <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315944/" target="_blank" rel="noopener noreferrer">machine learning can help battle the pandemic</a>, including better COVID-19 screening, diagnosis, contact tracing, and drug and vaccine development.</p><p>Cruzen said these kinds of tools represent a shift in how health systems can tackle a wide variety of problems.</p><p>"Health care has always used the past to predict the future, but not in this mathematical way," Cruzen said. "I think [Northwell Health's new predictive tool] really is a great first example of how we should be attacking a lot of things as we go forward."</p>Making machine-learning tools openly accessible
<p>Northwell Health has made its predictive tool <a href="https://github.com/northwell-health/covid-web-data-predictor" target="_blank">available for free</a> to any health system that wishes to utilize it.</p><p>"COVID is everybody's problem, and I think developing tools that can be used to help others is sort of why people go into health care," Dr. Cruzen said. "It was really consistent with our mission."</p><p>Open collaboration is something the world's governments and health systems should be striving for during the pandemic, said Michael Dowling, Northwell Health's president and CEO.</p><p>"Whenever you develop anything and somebody else gets it, they improve it and they continue to make it better," Dowling said. "As a country, we lack data. I believe very, very strongly that we should have been and should be now working with other countries, including China, including the European Union, including England and others to figure out how to develop a health surveillance system so you can anticipate way in advance when these things are going to occur."</p><p>In all, Northwell Health has treated more than 112,000 COVID patients. During the pandemic, Dowling said he's seen an outpouring of goodwill, collaboration, and sacrifice from the community and the tens of thousands of staff who work across Northwell.</p><p>"COVID has changed our perspective on everything—and not just those of us in health care, because it has disrupted everybody's life," Dowling said. "It has demonstrated the value of community, how we help one another."</p>3,000-pound Triceratops skull unearthed in South Dakota
"You dream about these kinds of moments when you're a kid," said lead paleontologist David Schmidt.
Excavation of a triceratops skull in South Dakota.
- The triceratops skull was first discovered in 2019, but was excavated over the summer of 2020.
- It was discovered in the South Dakota Badlands, an area where the Triceratops roamed some 66 million years ago.
- Studying dinosaurs helps scientists better understand the evolution of all life on Earth.
Credit: David Schmidt / Westminster College
<p style="margin-left: 20px;">"We had to be really careful," Schmidt told St. Louis Public Radio. "We couldn't disturb anything at all, because at that point, it was under law enforcement investigation. They were telling us, 'Don't even make footprints,' and I was thinking, 'How are we supposed to do that?'"</p><p>Another difficulty was the mammoth size of the skull: about 7 feet long and more than 3,000 pounds. (For context, the largest triceratops skull ever unearthed was about <a href="https://www.tandfonline.com/doi/abs/10.1080/02724634.2010.483632" target="_blank">8.2 feet long</a>.) The skull of Schmidt's dinosaur was likely a <em>Triceratops prorsus, </em>one of two species of triceratops that roamed what's now North America about 66 million years ago.</p>Credit: David Schmidt / Westminster College
<p>The triceratops was an herbivore, but it was also a favorite meal of the T<em>yrannosaurus rex</em>. That probably explains why the Dakotas contain many scattered triceratops bone fragments, and, less commonly, complete bones and skulls. In summer 2019, for example, a separate team on a dig in North Dakota made <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">headlines</a> after unearthing a complete triceratops skull that measured five feet in length.</p><p>Michael Kjelland, a biology professor who participated in that excavation, said digging up the dinosaur was like completing a "multi-piece, 3-D jigsaw puzzle" that required "engineering that rivaled SpaceX," he jokingly told the <a href="https://www.nytimes.com/2019/07/26/science/triceratops-skull-65-million-years-old.html" target="_blank">New York Times</a>.</p>Morrison Formation in Colorado
James St. John via Flickr
Triceratops illustration
Credit: Nobu Tamura/Wikimedia Commons |
World's oldest work of art found in a hidden Indonesian valley
Archaeologists discover a cave painting of a wild pig that is now the world's oldest dated work of representational art.
Pig painting at Leang Tedongnge in Indonesia, made at 45,500 years ago.
- Archaeologists find a cave painting of a wild pig that is at least 45,500 years old.
- The painting is the earliest known work of representational art.
- The discovery was made in a remote valley on the Indonesian island of Sulawesi.
Oldest Cave Art Found in Sulawesi
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="a9734e306f0914bfdcbe79a1e317a7f0"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/b-wAYtBxn7E?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>What can Avicenna teach us about the mind-body problem?
The Persian polymath and philosopher of the Islamic Golden Age teaches us about self-awareness.
The incredible physics behind quantum computing
Can computers do calculations in multiple universes? Scientists are working on it. Step into the world of quantum computing.
