Differences in the way that the Hubble constant—which measures the rate of cosmic expansion—are measured have profound implications for the future of cosmology.
- The Hubble constant is used to estimate the rate of expansion of the universe.
- There are two different ways to calculate its value, but they give different results.
- The difference may give physicists an opening to find new cosmic laws, but there is huge uncertainty about which path to take in finding them.
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Instead of insisting that we remain "free from" government control, we should view taking vaccines and wearing masks as a "freedom to" be a moral citizen who protects the lives of others.
- Now that the vaccine is becoming widely available, why do so many insist on not taking it?
- As different episodes in history have illustrated — including the building of an atomic bomb in the U.S. – true freedom is to choose to place the well-being of your family, community, and country above your own personal values.
- We shouldn't confuse the privilege of choice with a threat to personal freedom. In threatening times, our best defense is to act together to the benefit of all.
Hunter-gatherers probably had more spare time than you.
- For the species Homo sapiens, the Agricultural Revolution was a good deal, allowing the population to grow and culture to advance. But was it a good deal for individuals?
- Hunter-gatherers likely led lives requiring far less daily work than farmers, leading one anthropologist to call them the "original affluent society."
- The transition from hunter-gatherers to farmers may have occurred as a kind of trap in which the possibility of surplus during good years created population increases that had to be maintained.
75 years after Erwin Schrödinger's prescient description of something like DNA, we still don't know the "laws of life."
- Erwin Schrödinger's 1944 book "What Is Life?" revolutionized how physicists thought about the 'laws of life.' Schrödinger anticipated how DNA would hold life's blueprints.
- In recent years, however, a new path forward has appeared that holds a unique promise. Rather than reduce biology to physics, the new direction would transform them both.
- Scientists working across domains now think that understanding life requires putting a new actor on to the stage and letting it take the lead: the flow of information.
Left: "What is Life" by Erwin Schrödinger, Second Reprint, 1946. Right: Nobel Prize-winning Austrian physicist Dr. Erwin Schrödinger addresses the 5th World Power Conference in Vienna, Austria, 1956.
Why haven't we found aliens? Because we don't know what life is.<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="e556fe70053b8b1824b71ff74c71e4fe"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/NgRigA79J2E?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Two new studies examine ways we could engineer human wormhole travel.
- Sci-fi movies and books love wormholes—how else can we hope to travel through interstellar distances?
- But wormholes are notoriously unstable; it's hard to keep them open or make them big enough.
- Two new papers offer some hope in solving both of these issues, but at a high price.
A wormhole connecting two points in space.
Credit: TDHster via Adobe Stock<p>The idea of wormholes is not new. Its origins reach back to 1935 (and even earlier), when Albert Einstein and Nathan Rosen published a paper constructing what became known as an <a href="https://www.space.com/20881-wormholes.html" target="_blank">Einstein-Rosen bridge</a>. (The name 'wormhole' came up later, in a 1957 paper by Charles Misner and John Wheeler, Wheeler also being the one who coined the term 'black hole.') Basically, an Einstein-Rosen bridge is a connection between two distant points of the universe or possibly even different universes through a tunnel that goes into a black hole. Exciting as the possibility is, the throats of such bridges are notoriously unstable and any object with mass that ventures through it would cause it to collapse upon itself almost immediately, closing the connection. To force the wormholes to stay open, one would need to add a kind of exotic matter that has both negative energy density and pressure—not something that is known in the universe. (Interestingly, negative pressure is not as crazy as it seems; dark energy, the fuel that is currently accelerating the cosmic expansion, does it exactly because it has negative pressure. But negative energy density is a whole other story.)</p><p><span></span>If wormholes exist, if they have wide mouths, and if they can be kept open (three big but not impossible ifs) then it's conceivable that we could travel through them to faraway spots in the universe. Arthur C. Clarke used them in "2001: A Space Odyssey", where the alien intelligences had constructed a network of intersecting tunnels they used as we use the subway. Carl Sagan used them in "Contact" so that humans could confirm the existence of intelligent ETs. "Interstellar" uses them so that we can try to find another home for our species.</p>
Spirituality can be an uncomfortable word for atheists. But does it deserve the antagonism that it gets?
- While the anti-scientific bias of religious fundamentalism requires condemnation, if we take a broader view, does the human inclination towards spiritual practice still require the same antagonism? The answer, I think, is a definitive "No."
- Rather than ontological claims about what exists in the universe, the terms spiritual and sacred can describe the character of an experience. Instead of a "thing" they can refer to an attitude or an approach.
- One can be entirely faithful to the path of inquiry and honesty that is science while making it one aspect of a broader practice embracing the totality of your experience as a human being in this more-than-human world.