Apr 15, 2021 11:10 PM
(This post was last modified: Apr 15, 2021 11:12 PM by C C.)
Takeaways from this week’s Breakthrough Discuss meeting.
https://www.airspacemag.com/daily-planet...180977507/
EXCERPT: For me, the most eyebrow-raising talk was by Sofia Sheikh of Penn State University, who walked the audience through the story of a radio signal called BLC1, which made the news last year as a possible signal originating from the Centauri system. The evidence was a narrow-band signal (near 982 MHz) detected in April and May 2019, which seemed to shift over time, had a non-zero drift rate, and persisted for a few hours with repeated observations. While these are all traits you might expect from an artificial object orbiting Alpha Centauri, unfortunately it turned out to be nothing quite so exciting. Careful analysis revealed that the it was, in her words, “a pathological example of [radio] interference,” emanating from our own planet or Earth orbit.
The afternoon session ended with a poll I found very interesting. Of course, polls don’t really matter in science, which is driven by facts and not majority vote. But it was intriguing that 69 percent of the meeting’s virtual attendees thought it would be between 5 and 25 years before we discover life beyond Earth. Most people (44 percent) thought it would be found within our own Solar System, even though most of the attendees seemed to be exoplanet researchers.
Even though it was 2 a.m. at my home in Germany, I couldn’t miss the Yuri’s Night panel discussion about possible life in the Venusian clouds. The controversy isn’t resolved by any means, but it’s encouraging that an atmospheric sample return mission to Venus is now seriously being considered. In fact, reported Janusz Petkowski of MIT, Breakthrough Initiatives is sponsoring an MIT-led study of a mission to Venus to search for signs of life, or even life itself.
The third and last session, held on Tuesday, focused on how we might actually someday get to Alpha Centauri. Artur Davoyan of UCLA emphasized that the system could in principle be reached by a lightsail mission in as little as 20 years. But to get a large payload (and perhaps humans in the far future) to Alpha Centauri, a nuclear fusion propulsion system may be required. Michael Paluszek of Princeton Satellite Systems outlined the current state of the art of that technology. It’s certainly a challenging task, but it felt good to hear people discussing such daring visions! (MORE - details)
The universe is a machine that keeps learning, scientists say
https://www.popularmechanics.com/science...algorithm/
EXCERPTS: In fascinating new research, cosmologists explain the history of the universe as one of self-teaching, autodidactic algorithms. The scientists [...] say the universe has probed all the possible physical laws before landing on the ones we observe around us today.
[...] In their novella-length paper ... the researchers ... offer ideas “at the intersection of theoretical physics, computer science, and philosophy of science with a discussion from all three perspectives,” they write, teasing the bigness and multidisciplinary nature of the research.
Here’s how it works: Our universe observes a whole bunch of laws of physics, but the researchers say other possible laws of physics seem equally likely, given the way mathematics works in the universe. So if a group of candidate laws were equally likely, then how did we end up with the laws we really have?
The scientists explain: “The notion of ‘learning’ as we use it is more than moment-to-moment, brute adaptation. It is a cumulative process that can be thought of as theorizing, modeling, and predicting. For instance, the DNA/RNA/protein system on Earth must have arisen from an adaptive process, and yet it foresees a space of organisms much larger than could be called upon in any given moment of adaptation.”
[...] In the paper, the scientists define a slew of terms including how they’re defining “learning” in the context of the universe around us. The universe is made of systems that each have processes to fulfill every day, they say. Each system is surrounded by an environment made of different other systems...
Evolution is already a kind of learning, so when we suggest the universe has used natural selection as part of the realization of physics, we’re invoking that specific kind of learning [...] The researchers explain this distinction well: “In one sense, learning is nothing special; it is a causal process, conveyed by physical interactions. And yet we need to consider learning as special to explain events that transpire because of learning.” (MORE - details)
https://www.airspacemag.com/daily-planet...180977507/
EXCERPT: For me, the most eyebrow-raising talk was by Sofia Sheikh of Penn State University, who walked the audience through the story of a radio signal called BLC1, which made the news last year as a possible signal originating from the Centauri system. The evidence was a narrow-band signal (near 982 MHz) detected in April and May 2019, which seemed to shift over time, had a non-zero drift rate, and persisted for a few hours with repeated observations. While these are all traits you might expect from an artificial object orbiting Alpha Centauri, unfortunately it turned out to be nothing quite so exciting. Careful analysis revealed that the it was, in her words, “a pathological example of [radio] interference,” emanating from our own planet or Earth orbit.
The afternoon session ended with a poll I found very interesting. Of course, polls don’t really matter in science, which is driven by facts and not majority vote. But it was intriguing that 69 percent of the meeting’s virtual attendees thought it would be between 5 and 25 years before we discover life beyond Earth. Most people (44 percent) thought it would be found within our own Solar System, even though most of the attendees seemed to be exoplanet researchers.
Even though it was 2 a.m. at my home in Germany, I couldn’t miss the Yuri’s Night panel discussion about possible life in the Venusian clouds. The controversy isn’t resolved by any means, but it’s encouraging that an atmospheric sample return mission to Venus is now seriously being considered. In fact, reported Janusz Petkowski of MIT, Breakthrough Initiatives is sponsoring an MIT-led study of a mission to Venus to search for signs of life, or even life itself.
The third and last session, held on Tuesday, focused on how we might actually someday get to Alpha Centauri. Artur Davoyan of UCLA emphasized that the system could in principle be reached by a lightsail mission in as little as 20 years. But to get a large payload (and perhaps humans in the far future) to Alpha Centauri, a nuclear fusion propulsion system may be required. Michael Paluszek of Princeton Satellite Systems outlined the current state of the art of that technology. It’s certainly a challenging task, but it felt good to hear people discussing such daring visions! (MORE - details)
The universe is a machine that keeps learning, scientists say
https://www.popularmechanics.com/science...algorithm/
EXCERPTS: In fascinating new research, cosmologists explain the history of the universe as one of self-teaching, autodidactic algorithms. The scientists [...] say the universe has probed all the possible physical laws before landing on the ones we observe around us today.
[...] In their novella-length paper ... the researchers ... offer ideas “at the intersection of theoretical physics, computer science, and philosophy of science with a discussion from all three perspectives,” they write, teasing the bigness and multidisciplinary nature of the research.
Here’s how it works: Our universe observes a whole bunch of laws of physics, but the researchers say other possible laws of physics seem equally likely, given the way mathematics works in the universe. So if a group of candidate laws were equally likely, then how did we end up with the laws we really have?
The scientists explain: “The notion of ‘learning’ as we use it is more than moment-to-moment, brute adaptation. It is a cumulative process that can be thought of as theorizing, modeling, and predicting. For instance, the DNA/RNA/protein system on Earth must have arisen from an adaptive process, and yet it foresees a space of organisms much larger than could be called upon in any given moment of adaptation.”
[...] In the paper, the scientists define a slew of terms including how they’re defining “learning” in the context of the universe around us. The universe is made of systems that each have processes to fulfill every day, they say. Each system is surrounded by an environment made of different other systems...
Evolution is already a kind of learning, so when we suggest the universe has used natural selection as part of the realization of physics, we’re invoking that specific kind of learning [...] The researchers explain this distinction well: “In one sense, learning is nothing special; it is a causal process, conveyed by physical interactions. And yet we need to consider learning as special to explain events that transpire because of learning.” (MORE - details)
