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New study says cosmic acceleration and dark energy don't exist
An Oxford scientist claims a Nobel-Prize-winning conclusion is wrong.
- Paper by Oxford University physicist Subir Sarkar and his colleagues challenges how conclusions about cosmic acceleration and dark energy were reached.
- Physicists who proved cosmic acceleration shared a Nobel Prize.
- Sarkar used statistical analysis to question key data, but his methodology also has detractors.
Is our Universe's expansion speeding up? The 2011 Nobel Prize went to three scientists for proving just that. But what if the evidence they used to come up with this conclusion was wrongly interpreted and the supposed cosmic acceleration is simply an artifact of our movement through a local part of the Universe? In the big picture, there's no speeding up. What's also not there is the mysterious dark energy, thought to be creating that acceleration, says a new paper from a group of physicists who take issue with the supernovae-related evidence that was used to come up with the original Nobel-worthy conclusion.
The Nobel Prize for the cosmic acceleration idea, if you're wondering, was won by Saul Perlmutter, Brian Schmidt, and Adam Riess for "for the discovery of the accelerating expansion of the Universe through observations of distant supernovae". They used evidence from exploded stars called "la supernovae" or "standard candles" to show that the Universe's expansion was getting faster. These kinds of supernovas are so bright that we actually know their absolute brightness. This fact allows scientists to calculate the distance of these explosions from Earth, while studying the red shift in the light they emit points to the Universe's rate of expansion. In 1998, groups led by Perlmutter and Schmidt found light from 50 supernova to be dimmer than it was supposed to be, leading them to conclude that cosmic expansion was actually accelerating (thanks to dark energy – a yet-to-be-directly-observed enigmatic force that supposedly takes up 68% of all mass-energy in the Universe while causing it to expand).
But while the expansion has become accepted as science fact, there have been some who see things differently. Following up on his 2015 paper on this subject, Oxford University physicist Subir Sarkar and his colleagues at the Niels Bohr Institute and the Paris Institute of Astrophysics now published a second study taking issue with the idea of a Universe growing with acceleration.
As explained in Physics World, by statistically analyzing a sample of 740 la supernovae in their 2015 paper, Sarkar's team found "only marginal" support for cosmic acceleration with low statistical significance. The difference in their approach was in how they looked at the procedures used to calculate the absolute brightness of supernovae and how their light is absorbed by dust that gets in the way.
2011 Nobel Laureates in Physics, Saul Perlmutter, Brian P. Schmidt and Adam G. Riess2011 Nobel Laureates in Physics, Perlmutter, Schmidt and Riess, describe how an assumed error turned into the surprise discovery that the universe is expandi...
Critics of that paper abounded, taking issues with their methodology and pointing to other data that showed acceleration. Now, in the second paper, to be published in Astronomy and Astrophysics, the scientists continue to assail the supernovae evidence and the idea of cosmic acceleration by pointing to anomalies in the red-shift data and how calculations with respect to the Cosmic Microwave Background (CMB) are carried out.
"If you look at supernovae in only a small part of the sky, it would look like you had cosmic acceleration," Sarkar says. "But we are saying that it is just a local effect, that we are non-Copernican observers. It has nothing to do with the overall dynamics of the universe and therefore nothing to do with dark energy."
Riess disagrees with Sarkar's conclusions and data, calling it outdated. His team used data from 1,300 supernovae in their latest study and came up with clear-cut support for the acceleration's existence. Furthermore, he stated, "The evidence for cosmic acceleration and dark energy are much broader than only the supernovae Ia sample."
Who would argue with a Nobel Prize-winner? Subir Sarkar, who believes that "The CMB does not directly measure dark energy," adding "That is a widely propagated myth."
You can check out his new paper for yourself at arXiv.
Lisa Randall: Dark Energy Will Take Over
Physicist Lisa Randall on why dark energy doesn't dilute as the universe expands.
Emotional intelligence is a skill sought by many employers. Here's how to raise yours.
- Daniel Goleman's 1995 book Emotional Intelligence catapulted the term into widespread use in the business world.
- One study found that EQ (emotional intelligence) is the top predictor of performance and accounts for 58% of success across all job types.
- EQ has been found to increase annual pay by around $29,000 and be present in 90% of top performers.
Researchers hope the technology will further our understanding of the brain, but lawmakers may not be ready for the ethical challenges.
- Researchers at the Yale School of Medicine successfully restored some functions to pig brains that had been dead for hours.
- They hope the technology will advance our understanding of the brain, potentially developing new treatments for debilitating diseases and disorders.
- The research raises many ethical questions and puts to the test our current understanding of death.
What's dead may never die, it seems<p>The researchers did not hail from House Greyjoy — "What is dead may never die" — but came largely from the Yale School of Medicine. They connected 32 pig brains to a system called Brain<em>Ex</em>. Brain<em>Ex </em>is an artificial perfusion system — that is, a system that takes over the functions normally regulated by the organ. The pigs had been killed four hours earlier at a U.S. Department of Agriculture slaughterhouse; their brains completely removed from the skulls.</p><p>Brain<em>Ex</em> pumped an experiment solution into the brain that essentially mimic blood flow. It brought oxygen and nutrients to the tissues, giving brain cells the resources to begin many normal functions. The cells began consuming and metabolizing sugars. The brains' immune systems kicked in. Neuron samples could carry an electrical signal. Some brain cells even responded to drugs.</p><p>The researchers have managed to keep some brains alive for up to 36 hours, and currently do not know if Brain<em>Ex</em> can have sustained the brains longer. "It is conceivable we are just preventing the inevitable, and the brain won't be able to recover," said Nenad Sestan, Yale neuroscientist and the lead researcher.</p><p>As a control, other brains received either a fake solution or no solution at all. None revived brain activity and deteriorated as normal.</p><p>The researchers hope the technology can enhance our ability to study the brain and its cellular functions. One of the main avenues of such studies would be brain disorders and diseases. This could point the way to developing new of treatments for the likes of brain injuries, Alzheimer's, Huntington's, and neurodegenerative conditions.</p><p>"This is an extraordinary and very promising breakthrough for neuroscience. It immediately offers a much better model for studying the human brain, which is extraordinarily important, given the vast amount of human suffering from diseases of the mind [and] brain," Nita Farahany, the bioethicists at the Duke University School of Law who wrote the study's commentary, told <em><a href="https://www.nationalgeographic.com/science/2019/04/pig-brains-partially-revived-what-it-means-for-medicine-death-ethics/" target="_blank">National Geographic</a>.</em></p>
An ethical gray matter<p>Before anyone gets an <em>Island of Dr. Moreau</em> vibe, it's worth noting that the brains did not approach neural activity anywhere near consciousness.</p><p>The Brain<em>Ex</em> solution contained chemicals that prevented neurons from firing. To be extra cautious, the researchers also monitored the brains for any such activity and were prepared to administer an anesthetic should they have seen signs of consciousness. </p><p>Even so, the research signals a massive debate to come regarding medical ethics and our definition of death. </p><p>Most countries define death, clinically speaking, as the irreversible loss of brain or circulatory function. This definition was already at odds with some folk- and value-centric understandings, but where do we go if it becomes possible to reverse clinical death with artificial perfusion?</p><p>"This is wild," Jonathan Moreno, a bioethicist at the University of Pennsylvania, told <a href="https://www.nytimes.com/2019/04/17/science/brain-dead-pigs.html" target="_blank">the <em>New York Times</em></a>. "If ever there was an issue that merited big public deliberation on the ethics of science and medicine, this is one."</p><p>One possible consequence involves organ donations. Some European countries require emergency responders to use a process that preserves organs when they cannot resuscitate a person. They continue to pump blood throughout the body, but use a "thoracic aortic occlusion balloon" to prevent that blood from reaching the brain.</p><p>The system is already controversial because it raises concerns about what caused the patient's death. But what happens when brain death becomes readily reversible? Stuart Younger, a bioethicist at Case Western Reserve University, <a href="https://www.nature.com/articles/d41586-019-01216-4#ref-CR2" target="_blank">told <em>Nature</em></a> that if Brain<em>Ex</em> were to become widely available, it could shrink the pool of eligible donors.</p><p>"There's a potential conflict here between the interests of potential donors — who might not even be donors — and people who are waiting for organs," he said.</p><p>It will be a while before such experiments go anywhere near human subjects. A more immediate ethical question relates to how such experiments harm animal subjects.</p><p>Ethical review boards evaluate research protocols and can reject any that causes undue pain, suffering, or distress. Since dead animals feel no pain, suffer no trauma, they are typically approved as subjects. But how do such boards make a judgement regarding the suffering of a "cellularly active" brain? <a href="https://bigthink.com/philip-perry/after-death-youre-aware-that-youve-died-scientists-claim" target="_blank">The distress of a partially alive brain</a>? </p><p>The dilemma is unprecedented.</p>
Setting new boundaries<p>Another science fiction story that comes to mind when discussing this story is, of course, <em>Frankenstein</em>. As Farahany told <em>National Geographic</em>: "It is definitely has [sic] a good science-fiction element to it, and it is restoring cellular function where we previously thought impossible. But to have <em>Frankenstein</em>, you need some degree of consciousness, some 'there' there. [The researchers] did not recover any form of consciousness in this study, and it is still unclear if we ever could. But we are one step closer to that possibility."</p><p>She's right. The researchers undertook their research for the betterment of humanity, and we may one day reap some unimaginable medical benefits from it. The ethical questions, however, remain as unsettling as the stories they remind us of.</p>
Starting and running a business takes more than a good idea and the desire to not have a boss.
- Anyone can start a business and be an entrepreneur, but the reality is that most businesses will fail. Building something successful from the ground up takes hard work, passion, intelligence, and a network of people who are equally as smart and passionate as you are. It also requires the ability to accept and learn from your failures.
- In this video, entrepreneurs in various industries including 3D printing, fashion, hygiene, capital investments, aerospace, and biotechnology share what they've learned over the years about relationships, setting and attaining goals, growth, and what happens when things don't go according to plan.
- "People who start businesses for the exit, most of them will fail because there's just no true passion behind it," says Miki Agrawal, co-founder of THINX and TUSHY. A key point of Agrawal's advice is that if you can't see yourself in something for 10 years, you shouldn't do it.
After a decade of failed attempts, scientists successfully bounced photons off of a reflector aboard the Lunar Reconnaissance Orbiter, some 240,000 miles from Earth.
- Laser experiments can reveal precisely how far away an object is from Earth.
- For years scientists have been bouncing light off of reflectors on the lunar surface that were installed during the Apollo era, but these reflectors have become less efficient over time.
- The recent success could reveal the cause of the degradation, and also lead to new discoveries about the Moon's evolution.
A close-up photograph of the laser reflecting panel deployed by Apollo 14 astronauts on the Moon in 1971.
NASA<p>The technology isn't quite new. During the Apollo era, astronauts installed on the lunar surface five reflecting panels, each containing at least 100 mirrors that reflect back to whichever direction it's coming from. By bouncing light off these panels, scientists have been able to learn, for example, that the Moon is drifting away from Earth at a rate of about 1.5 inches per year.<br></p><p style="margin-left: 20px;">"Now that we've been collecting data for 50 years, we can see trends that we wouldn't have been able to see otherwise," Erwan Mazarico, a planetary scientist from NASA's Goddard Space Flight Center in Greenbelt, Maryland, <a href="https://www.nasa.gov/feature/goddard/2020/laser-beams-reflected-between-earth-and-moon-boost-science" target="_blank" rel="dofollow">said</a>. "Laser-ranging science is a long game."</p>
NASA's Lunar Reconnaissance Orbiter (LRO)
NASA<p>But the long game poses a problem: Over time, the panels on the Moon have become less efficient at bouncing light back to Earth. Some scientists suspect it's because dust, kicked up by micrometeorites, has settled on the surface of the panels, causing them to overheat. And if that's the case, scientists need to know for sure.</p><p>That's where the recent LRO laser experiment comes in. If scientists find discrepancies between the data sent back by the LRO reflector and those on the lunar surface, it could reveal what's causing the lunar reflectors to become less efficient. They could then account for these discrepancies in their models.</p>