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Warp speed: How the outer edges of the universe travel faster than the speed of light
The answer can give us an indication of where our universe is headed and how it might end.
As children it’s driven into us in early science classes as a cardinal rule: nothing can travel faster than light. But at least one thing is thought to, or at least appears to be—the fundamental material of the universe itself. Astronomers believe there are galaxies moving away from ours at a rate faster than light speed. As a result, we’ll likely never get to see them.
13.78 billion years ago, the solidarity exploded in an event we call the Big Bang. This was a point in the universe of infinite density and heat. After the explosion, the universe expanded at the rate of 10¹⁶ in a fraction of a second, during a period of inflation that occurred at a velocity faster than the speed of light. After that, you’d think that the universe would expand at a constant rate or even slow down. If it had slowed down, we’d be able to see right to the edge as there wouldn’t be anywhere that would be too far for light to travel.
Instead, the rate of universal expansion has been speeding up. And there are places in the universe that are so far away, photons will never make it there. As a result, the edges of our cosmos remain in shadow. What lies beyond is an intrepid mystery we might not ever solve.
Expansion still occurs today, quizzically, at an ever-increasing rate. Note that it isn’t just matter but the fabric of the universe itself, as the matter in a way rides atop of it. What’s more, the galaxies farther away appear to be moving faster than those closer to us. There may even be ones close by that are moving faster than light. If there are, we’ll find them difficult to detect.
Timeline of the expansion of the universe since the Big Bang. Credit: NASA/WMAP Science Team.
Galaxies and other matter are like sesame seeds resting atop a piece of dough, with the dough standing in for the fabric of the universe. When we place the dough in an oven it expands, and those seeds on the outside rim appear as if they expand out faster than those near the middle. The same may be true of the universe.
The rate of universal expansion is 68 kilometers per second per megaparsec. A parsec is 3.26 million light-years, while a megaparsec is a million parsecs. For every parsec away a galaxy is from ours, you add 68 km/s to its velocity.
Once we get out to about 4,200 megaparsecs away, galaxies travel faster than light. Just to boggle your mind, consider that 4,200 megaparsecs = 130,000,000,000,000,000,000,000 km. Astronomers can calculate how far away a galaxy is by the distance it’s gone and the time it takes to travel that distance, all by carefully observing the light coming from it.
We can tell how far away a galaxy is by something called red shift and blue shift. As a galaxy moves away, the light from it takes longer to reach us. All that space between the galaxy and us forces the wavelength of the light to elongate, moving it toward the red part of the spectrum. This is known as red shift. Those objects moving away from us appear red while those moving toward us, whose wavelengths shorten, appear blue.
Panoramic view of the entire near-infrared sky. This image shows how the galaxies beyond are own located. The image was taken by the 2MASS Extended Source Catalog (XSC). This contains over 1.5 million galaxies and half a billion stars. The galaxies are coded by redshift, indicated by the numbers in parentheses). Credit: Thomas Jarrett, IPAC/Caltech.
The furthest thing out there that we can detect is the cosmic microwave background (CMB). This is the light residue left over from the Big Bang. Created 13.7 billion years ago, it now stretches out homogenously 46 billion light-years away in every direction.
According to Paul Sutter, Ohio State University astrophysicist and COSI Science Center Chief Scientist, the notion that the speed of light is the topmost speed for matter (or information), comes from Einstein’s special relativity. But this is part of what he calls “local physics.” It can and in fact must be applied to things nearby.
Far out in the deepest reaches of space, however, general relativity applies, but special relativity may not and with it, the speed of light as the topmost velocity becomes less certain. So what are the implications of an ever-accelerating universe? Nothing short of a cosmic heat death. Over billions of years, galaxies are thought to expand so far out from each other that the gases that congregate to form stars won’t be able to get together. They’ll be spread too thin.
Light from other galaxies won’t be able to reach us, either. And with no new stars forming, they’ll be none to replace those that have burned out. That means a slow fading of all light in the universe, and in its place, a cosmos forever shrouded in frozen darkness. That’s of course unless other forces can counteract this phenomenon.
Is there anything else faster than the speed of light? Find out here:
Scientists use new methods to discover what's inside drug containers used by ancient Mayan people.
- Archaeologists used new methods to identify contents of Mayan drug containers.
- They were able to discover a non-tobacco plant that was mixed in by the smoking Mayans.
- The approach promises to open up new frontiers in the knowledge of substances ancient people consumed.
PARME staff archaeologists excavating a burial site at the Tamanache site, Mérida, Yucatan.
While not the first such minister, the loneliness epidemic in Japan will make this one the hardest working.
- The Japanese government has appointed a Minister of Loneliness to implement policies designed to fight isolation and lower suicide rates.
- They are the second country, after the U.K., to dedicate a cabinet member to the task.
- While Japan is famous for how its loneliness epidemic manifests, it isn't alone in having one.
The Ministry of Loneliness<iframe width="730" height="430" src="https://www.youtube.com/embed/I5FIohjZT8o" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p><a href="https://www.jimin.jp/english/profile/members/114749.html" target="_blank" rel="noopener noreferrer">Tetsushi Sakamoto</a>, already in the government as the minister in charge of raising Japan's low birthrate and revitalizing regional economies, was appointed this <a href="https://www.japantimes.co.jp/news/2021/02/21/national/japan-tackles-loneliness/" target="_blank" rel="noopener noreferrer">month</a> to the additional role. He has already announced plans for an emergency national forum to discuss the issue and share the testimony of lonely <a href="https://www.japantimes.co.jp/news/2021/02/12/national/loneliness-isolation-minister/" target="_blank" rel="noopener noreferrer">individuals</a>.</p><p>Given the complexity of the problem, the minister will primarily oversee the coordination of efforts between different <a href="https://www.insider.com/japan-minister-of-loneliness-suicides-rise-pandemic-2021-2" target="_blank" rel="noopener noreferrer">ministries</a> that hope to address the issue alongside a task <a href="https://www.japantimes.co.jp/news/2021/02/21/national/japan-tackles-loneliness/" target="_blank" rel="noopener noreferrer">force</a>. He steps into his role not a moment too soon. The loneliness epidemic in Japan is uniquely well known around the world.</p><p><a href="https://en.wikipedia.org/wiki/Hikikomori" target="_blank" rel="noopener noreferrer"><em>Hikikomori</em></a><em>,</em> often translated as "acute social withdrawal," is the phenomenon of people completely withdrawing from society for months or years at a time and living as modern-day hermits. While cases exist in many <a href="https://www.frontiersin.org/articles/10.3389/fpsyt.2019.00247/full" target="_blank" rel="noopener noreferrer">countries</a>, the problem is better known and more prevalent in Japan. Estimates vary, but some suggest that one million Japanese live like this and that 1.5 million more are at <a href="https://www.nationalgeographic.com/photography/article/japan-hikikomori-isolation-society" target="_blank" rel="noopener noreferrer">risk</a> of developing the condition. Individuals practicing this hermitage often express contentment with their isolation at first before encountering severe symptoms of loneliness and <a href="https://www.sciencedaily.com/releases/2020/01/200110155241.htm" target="_blank" rel="noopener noreferrer">distress</a>.</p><p><a href="https://en.wikipedia.org/wiki/Kodokushi" target="_blank" rel="noopener noreferrer"><em>Kodokushi</em></a>, the phenomenon of the elderly dying alone and remaining undiscovered for some time due to their isolation, is also a widespread issue in Japan that has attracted national attention for decades.</p><p>These are just the most shocking elements of the loneliness crisis. As we've discussed before, loneliness can cause health issues akin to <a href="https://www.inc.com/amy-morin/americas-loneliness-epidemic-is-more-lethal-than-smoking-heres-what-you-can-do-to-combat-isolation.html" target="_blank" rel="noopener noreferrer">smoking</a>. A lack of interaction within a community can cause social <a href="https://bigthink.com/in-their-own-words/how-religious-neighbors-are-better-neighbors" target="_self">problems</a>. It is even associated with changes in the <a href="https://bigthink.com/mind-brain/loneliness-brain" target="_self">brain</a>. While there is nothing wrong with wanting a little time to yourself, the inability to get the socialization that many people need is a real problem with real <a href="https://bigthink.com/mind-brain/brain-loneliness-hunger" target="_self">consequences</a>.</p>
The virus that broke the camel's back<iframe width="730" height="430" src="https://www.youtube.com/embed/Hp-L844-5k8" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe><p> A global loneliness pandemic existed before COVID-19, and the two working in tandem has been catastrophic. </p><p>Japanese society has always placed a value on solitude, often associating it with self-reliance, which makes dealing with the problem of excessive solitude more difficult. Before the pandemic, 16.1 percent of Japanese seniors reported having nobody to turn to in a time of need, the highest rate of any nation <a href="https://www.japantimes.co.jp/news/2021/02/21/national/japan-tackles-loneliness/" target="_blank" rel="noopener noreferrer">considered</a>. Seventeen percent of Japanese men surveyed in 2005 said that they "rarely or never spend time with friends, colleagues, or others in social groups." This was three times the average rate of other <a href="http://www.oecd.org/sdd/37964677.pdf" target="_blank" rel="noopener noreferrer">countries</a>. </p><p>American individualism also creates a fertile environment for isolation to grow. About a month before the pandemic started, nearly<a href="https://www.npr.org/sections/health-shots/2020/01/23/798676465/most-americans-are-lonely-and-our-workplace-culture-may-not-be-helping" target="_blank" rel="noopener noreferrer"> 3 in 5</a> Americans reported being lonely in a <a href="https://www.cigna.com/about-us/newsroom/studies-and-reports/combatting-loneliness/" target="_blank" rel="noopener noreferrer">report</a> issued by Cigna. This is a slight increase over previous studies, which had been pointing in the same direction for years. </p><p>In the United Kingdom, the problem prompted the creation of the Jo Cox Commission on Loneliness. The commission's <a href="https://www.ageuk.org.uk/globalassets/age-uk/documents/reports-and-publications/reports-and-briefings/active-communities/rb_dec17_jocox_commission_finalreport.pdf" target="_blank" rel="noopener noreferrer">final report </a>paints a stark picture of the U.K.'s situation in 2017, with millions of people from all parts of British society reporting feeling regular loneliness at a tremendous cost to personal health, society, and the economy.</p><p>The report called for a lead minister to address the problem at the national level, incorporating government action with the insights provided by volunteer organizations, businesses, the NHS, and other organizations on the crisis's front lines. Her Majesty's Government acted on the report and appointed the first Minister for Loneliness in <a href="https://time.com/5248016/tracey-crouch-uk-loneliness-minister/" target="_blank" rel="noopener noreferrer">2018</a>, <a href="https://en.wikipedia.org/wiki/Tracey_Crouch" target="_blank" rel="noopener noreferrer">Tracey Crouch</a>, and dedicated millions of pounds to battling the problem. </p><p>The distancing procedures necessitated by the COVID-19 epidemic saved many lives but exacerbated an existing problem of loneliness in many parts of the world. While the issue had received attention before, Japan's steps to address the situation suggest that people are now willing to treat it with the seriousness it deserves.</p><p>--</p><p><em>If you or a loved one are having suicidal thoughts, help is available. The suicide prevention hotline can be reached at 1-800-273-8255.</em></p>
MIT professor Azra Akšamija creates works of cultural resilience in the face of social conflict.