“In the media age, everybody was famous for 15 minutes. In the Wikipedia age, everybody can be an expert in five minutes. Special bonus: You can edit your own entry to make yourself seem even smarter.” ―Stephen Colbert
It’s been another fun-and-fact-filled week here at Starts With A Bang! (And did you know I have a wikipedia page? I do! And most of the facts there are even correct!) I’m planning out the next edition of the Starts With A Bang podcast, which should cover the science that the James Webb Space Telescope will reveal starting in just over a year; yes, we’re just 13 months from launch! We’re also looking into starting a video series, with the financial (and idea-filled) help of our generous Patreon supporters, as well as some exciting interviews coming up in advance of the October 15th release of Treknology, which should take the world by storm! Now, let’s have a look back at all our article from this past week:
- Can normal stars make heavier (and less stable) elements than iron? (for Ask Ethan),
- Five reasons why the signals from Stephen Hawking’s Breakthrough Initiative aren’t aliens (for Mostly Mute Monday),
- The Sun’s Energy Doesn’t Come From Fusing Hydrogen Into Helium (Mostly),
- The Terrifying Physics Of How Wildfires Spread So Fast,
- The Greatest Cosmic Puzzle: Astronomers Find Stars That Appear Older Than The Universe,
- Why The Sky Is Blue, According To Science.
So with all the announcements out of the way, let’s dive right into our comments of the week!
From Elle H.C. on Einstein’s opinion on the aether: “To quote Einstein:
“We may say that according to the general theory of relativity space is endowed with physical qualities; in this sense, therefore, there exists an aether. According to the general theory of relativity space without aether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring-rods and clocks), nor therefore any space-time intervals in the physical sense. But this aether may not be thought of as endowed with the quality characteristic of ponderable media, as consisting of parts which may be tracked through time. The idea of motion may not be applied to it.”
The scientific community has ruled against Einstein on this topic…”
It’s not so much that “the scientific community” made a ruling as it is that Einstein’s “unthinkable” interpretation was actually equivalent to his own interpretation. If you call the mathematical structure of “spacetime” an “aether,” I can’t really say anything to change your mind, but you are redefining words to make the “aether” exist. If that were the case, let me turn it around on you: what would an aether-less spacetime look like?
The conventional thinking is that when we talk about empty space — the “vacuum” — we are talking about what we physically know as nothingness itself. This is what contains the entire Universe. Nothing more is required. You can certainly invent something more (or something else), but unless it has a physical difference from the predictions of nothingness itself, it doesn’t have a physical meaning.
From eric on the spreading of quantum wavefunctions: “Many (I want to say ‘all’ but I’m not sure about that) wavefunctions are much larger than what we would consider the discrete particle to be. The photon is, in reality, ‘smeared out’ over a much larger area.”
The important thing to remember is that wavefunctions are not static entities, but rather that they spread out over time! There is an uncertainty inherent to anything’s position and momentum, and so that means that if you know where something is and how it’s moving at any particular moment in time, even to an accuracy of Planck’s constant, there is an uncertainty that grows with time and distance as far as where this particle will be in the future. So if you take the extrema of the possibilities and allow that sort of spreading, it’s pretty impossible to not have some portion of the wavefunction wind up a seemingly absurd distance away.
The only way out is to make a high-energy-enough measurement to collapse the wavefunction, which is where the “quantum zeno’s paradox” comes in, and why a watched radioactive atom doesn’t decay the same as one that you simply leave alone.
From Steve Blackband on a book recommendation: “Highly recommend Rise of the Rocket Girls by Nathalia Holt. An easy holiday read, [focusing] on the efforts of the women ‘computers’ in the space program, much like the book by Dava Sobel called the Glass Universe [focusing] on the women who read astronomy photographic plates.”
I haven’t come across this book, so I’m very curious to learn about it! For anyone interested in the history of both the space program and the role that women in science have played, it gets good reviews from people I respect. Pick up a copy at Amazon here.
From Sinisa Lazarek about whether Einstein is always a good authority about physics: “Well, Einstein also said: “There is not the slightest indication that nuclear energy will ever be obtainable. It would mean that the atom would have to be shattered at will.”
Just because someone made great contribution in one area, doesn’t make him absolutely correct about everything.”
It goes beyond that, actually. Just because someone is an expert and made a great contribution in one area doesn’t mean they are correct about everything they say even in that area. Alan Guth was the inventor and originator of inflation, yet his original model was untenable and everyone knew it. Fred Hoyle made tremendous strides in uncovering the properties of the primordial light in the Universe yet would not accept that his model for departures from a blackbody spectrum did not fit the observations. Einstein was not only wrong about many aspects of quantum and nuclear physics (despite winning a Nobel for the photoelectric effect), but made many mistakes concerning relativity, including the declaration that gravitational waves were a physical impossibility.
The idea that “one should listen to the master” is absurd; you should listen to the correct argument that is made for the correct reasons, regardless of who makes it. Einstein was wrong. A lot. So was pretty much every scientist in history. We must tread carefully here, and not fall for the fallacy of picking the quotes and statements that support what we want reality to be.
From John on whether science describes or explains: “One of the unresolved, and possibly unresolvable, tensions in Science – in the instance Physics – is whether it describes or explains. As seen above, some are firmly (even emphatically) members of the descriptive camp. I found Ethan’s “What’s the quantum reason that sodium and water react?” (05-AUG-17) a delightful example of Science’s – in that instance physical Chemistry – ability to explain.”
I think this is an interesting topic to consider. The sodium-and-water example feels like a good explanation, rather than merely a description, because we have a deep understanding of what physics underlies it. If you ask “why do the quantum energy levels behave as they do,” you’re likely to come away with more of what feels like a description than an explanation, even though those quantum energy levels are what power the sodium-and-water reaction. If we have a deeper layer (or two, or more) of understanding than what you’re asking about, it’s easier to explain what’s going on. But if you’re at that deepest level that humanity has ever gone, usually it only feels descriptive.
At that most fundamental level, I don’t know that it’s possible to do any better.
From Frank on the brightness of the Sun’s center: “All cutaway views of sun I had seen show its center as the brightest region. But I think if we could really see inside of sun almost all of it would look black. Because I think visible light is produced close to the surface. Am I right on this?”
You know, I was all prepared to write to you about blackbody spectra, the energy produced, how collisions between gamma-ray photons and particles in the Sun’s core produce thermalization and a very hot, intense set of radiation that spans the full electromagnetic spectrum, and so on. I was prepared to show you images like this:
And to tell you that being hotter meant more radiation of all wavelengths, so long as you obey that blackbody law. And then I saw, just below, that Candice Elliot has beaten me to it, providing an excellent explanation.
This is one of those Berkelian questions… since we can’t actually do a cut-away. However, no, the region inside of the core would still be amazingly hot and does radiate in the visible region… but that most of the energy in the core is radiating at high energies up into the gamma. So, it would still be bright in the visible. You might want to look up ‘black body radiation’. As the temperature goes up, the energy peak goes up (shorter wavelength/higher energy per photon)… but so does the amount of energy in non-peak wavelengths.
As the energy passes from the convention zone to the surface, the volume of the mass that is available goes up so the temp goes down and at the very surface, the temp cools such that the peak is now in the visible range (of course it is! That’s because we evolved to use the peak range to see!)
So, good job! In short, the core of the Sun would be brighter than the core of any cooler blackbody, all other things being equal, no matter which wavelength of light you looked at. Remember, hotter objects contain more energy overall, and that affects what you “see,” among a myriad of other things!
From Ragtag Media on the cause of wildfires: “Or rather The Terrifying Actions Of Environmentalist Cause Disaster.
Thank a Spotted Owl”
What many people on both sides of the political aisle — including those on the far right who blame environmentalism for hampering the logging industry and those who blame the logging industry for destroying America’s natural resources — don’t realize is how many strides have been made in the practice of sustainable logging over the years. All the major logging companies, like Weyerhauser (which dominates where I live), now treat lumber as a crop. You cut a portion, you replant, you let it grow, you harvest, etc. This is how it works, it’s good for the environment, etc.
However, there are a great many compelling reasons to think that we have not yet arrived at the ideal fire, wildlife, flora-and-fauna management system. For protected lands like forests, natural fires do occur. Should we clear out the underbrush? If so, by how much? Should we engage in controlled burns? Of what magnitude? These are questions still being discussed today, and they should still be discussed. There is much to still learn.
With that said, I would hope that everyone here would be against arson. Would be against throwing fireworks into the woods when there’s a burn ban. And would be against the 80% of wildfires that are caused by human negligence and/or malice. My wife and I had our lives endangered by one that was started atop Powell Butte a few years ago just outside of Portland, OR, by… a group of teenagers. We were the first to call 911 and alert them. We were out hiking and had to race back to our car and leave. We got out, but… I mean, come on. It’s okay to say, “arson is bad,” and to call irresponsible fire-starting exactly what it is: arson.
At least Alan G. agrees with me:
“Well, it would seem prudent that the first and best line of defense is for humans to stop setting wildfires.”
From MobiusKlein on the culture wars: “Not every science discussion needs to start with a Culture War rerun.”
The cynical part of me wants to say, “have you been on the internet before?”
But I think this is a good place to bring something up about forest management that’s very important. A lot of people focus on the “renewing” effect that burns have, clearing out the old, dead brush and allowing the ecosystem to start over. Because of human activity, a lot of what will first grow when we have a wildfire, will be invasive species. If they take root in the early stages, they can choke out the natural habitat which would have grown there if not for the introduction of these species by human activity.
If we want to restore the natural habitat after a wildfire occurs, in many locations (like in the Columbia Gorge), we absolutely need human intervention to properly manage the restoration. This is a big part of what the forest service does, and will be doing in the coming months after the fires are put out.
From Carl on how a star appears older than the age of the Universe: “Two words: stellar progeria.”
Certainly, if the star actually does appear to be 14.5 billion years old, something must’ve happened to cause that “artificially large” age we ascribe to it. But what was it? For the last word of the week, Omega Centauri has an idea:
“What if the star originally had a brown dwarf companion, and was a bit lower in mass early on then would appear to make sense today? So say after a few billion years, it merged with its brown dwarf gaining a few percent of mass.”
This actually goes the wrong way; this would make a star appear younger than it actually is, akin to blue stragglers. What would work is for something to have stripped a bit of the mass away from the star. If you can have a more massive star age, burn through its fuel, and then lose some of its mass, it will evolve more quickly. Even if that’s the case, the big question is how. Off the top of my head, my first idea is that this star began in a globular cluster or a multi-star system, was the less-massive companion in a binary (or more) system, it had some of its mass siphoned off after billions of years, and then a close gravitational interaction with another body ejected it into the galaxy, away from its former companions, where we observe it today.
But I have no evidence for this. The Universe is like a detective story with insufficient clues. Until we catch another, similar star doing something as compelling as this, we don’t know whether this explanation is possible. Regardless, we can only see the survivors in the Universe today, and infer what might have (or must have) happened in the past. The rest is why this is such a great cosmic puzzle!
See you back here next week for more exciting stories of science and the Universe here on Starts With A Bang!