Scientists Didn’t Really Find The First Molecule In The Universe
“All of the early Universe’s helium should have been destroyed when hydrogen became neutral, as helium hydride is far less energetically favorable than the formation of neutral hydrogen. Once you cool below a certain critical threshold, your helium hydride will interact with neutral hydrogen, preferentially forming hydrogen molecules (H2) and isolated helium atoms (He). The Universe’s first molecule didn’t last long; by the time perhaps 500,000 years passed, it was all gone.
But later on, even in the modern Universe, there’s a perfect candidate location where helium hydride should exist in our Universe today: in the ionized plasmas of dying Sun-like stars. With temperatures high enough to ionize hydrogen, but plenty of neutral helium expelled from the dying stars outer layers, these planetary nebulae should be ideal homes for helium hydride.”
We found the first molecule in the Universe! Well, not quite. Helium hydride, formed between neutral helium atoms and ionized hydrogen nulcei, is an ion that gets created at specific temperatures, when hydrogen is ionized but helium is not. We created it in the laboratory way back in 1925, and astrophysicists theorized that it would be created in two places: in ionized plasmas around dying Sun-like stars, and in the very early Universe, when it was still too hot to form neutral hydrogen atoms. In big, interesting news, we’ve finally discovered helium hydride in space, finding it using the SOFIA telescope and observing the planetary nebula NGC 7027. It’s a remarkable story all on its own merits.
But this isn’t the same as the helium hydride formed in the aftermath of the Big Bang. That was all destroyed long ago, and none of it remains to be seen today.
Quarks Don’t Actually Have Colors
“We may call it color charge, but the strong nuclear force obeys rules that are unique among all the phenomena in the Universe. While we ascribe colors to quarks, anticolors to antiquarks, and color-anticolor combinations to gluons, it’s only a limited analogy. In truth, none of the particles or antiparticles have a color at all, but merely obey the rules of an interaction that has three fundamental types of charge, and only combinations that have no net charge under this system are allowed to exist in nature.
This intricate interaction is the only known force that can overcome the electromagnetic force and keep two particles of like electric charge bound together into a single, stable structure: the atomic nucleus. Quarks don’t actually have colors, but they do have charges as governed by the strong interaction. Only with these unique properties can the building blocks of matter combine to produce the Universe we inhabit today.”
At a fundamental level, forces like gravity are easy. There’s only one type of charge, mass/energy, and it’s always attractive. The electric force is a little more complex, with two types of fundamental electric charges, positive or negative, where like charges repel and opposite charges attract. But in the theory of the strong interactions, there are three fundamental types of charge, and that changes everything. We call this color charge because of a good analogy with how additive and subtractive colors work, but we can learn even more by investigating where the analogies break down.
Nature is bizarre, but if we’re careful we can understand it. Quarks don’t actually have colors, but what they do have may be even more interesting. Come find out about it today.
Could An Incompleteness In Quantum Mechanics Lead To Our Next Scientific Revolution?
“But in the quantum Universe, this notion of relativistic causality isn’t as straightforward or universal as it would seem. There are many properties that a particle can have — such as its spin or polarization — that are fundamentally indeterminate until you make a measurement. Prior to observing the particle, or interacting with it in such a way that it’s forced to be in either one state or the other, it’s actually in a superposition of all possible outcomes.
Well, you can also take two quantum particles and entangle them, so that these very same quantum properties are linked between the two entangled particles. Whenever you interact with one member of the entangled pair, you not only gain information about which particular state it’s in, but also information about its entangled partner.”
One of the most important ideas in classical physics are those of locality and causality: that objects in close proximity can affect one another through the forces they exert on one another, which are limited by the speed of light. But quantum mechanics turns much of that on its head, where locality doesn’t appear to be a fundamental property of reality at all. Yet one of the most remarkable ideas of all out there conjectures that quantum gravity, which contains fundamental non-localities, could be described by variables that completely explain what we view as non-locality in standard quantum physics.
Could this be right? Lee Smolin is giving a talk on that today, and I’ll be live-blogging it as it happens. Don’t miss this one-of-a-kind event!
This Is How To Bring Dark Skies Back In An Increasingly Developed World
“A dark night sky is something we not only all deserve, it’s something that we could very easily have for a relatively small investment. The benefits, in addition to long-term cost savings, education, and the environmental positives, can be taken in all at once by everyone who both lives in, or simply passes through, your town.
And for those of you still asking, “what benefit is that?”
As soon as you encounter your first dark sky community, you’ll see for yourself that there’s no explanation required. To take it all in, just look up.”
When was the last time you saw the Milky Way? If you’re like 99% of the United States or Europe, it wasn’t from your own backyard. While you might assume that’s because we need to have well-lit areas where most of us live, that’s only partially correct. It’s because we choose to have brightly-lit areas to meet our safety and commercial nighttime needs, but there’s a fundamental difference between well-lit and brightly-lit. More than 20 independent communities have taken all the steps necessary to restore darkness to their areas, following the recommendations and getting certified by the IDA: the International Dark Sky Association.
Forget about asking, “why aren’t there more?” Instead, try being the change you want to see, and work to bring dark skies, as well as health and environmental benefits, back to your own community!
The Two Scientific Ways We Can Improve Our Images Of Event Horizons
“By properly equipping and calibrating each participating telescope, the resolution sharpens, replacing an individual telescope’s diameter with the array’s maximum separation distance. At the Event Horizon Telescope’s maximum baseline and wavelength capabilities, it will attain resolutions of ~15 μas: a 50% improvement over the first observations. Currently limited to 345 GHz, we could strive for higher radio frequencies like 1-to-1.6 THz, progressing our resolution to just ~3-to-5 μas. But the greatest enhancement would come from extending our radio telescope array into space.”
It’s absolutely incredible that we’ve got our first image of a black hole’s event horizon, and a monumental achievement for science. But like all scientists, opening the door to a new “first” only increases our drive to surpass what we’ve accomplished and improve our capabilities beyond anything we’ve achieved before. For an event horizon, that means higher resolutions and sharper images, and we have two scientific ways to get there: probing higher frequencies and extending the length of our baseline to beyond the limits of planet Earth.
Both of these are technologically possible, and will likely, over the coming years and decades, be how we push past our scientific limits. Come learn how.
Ask Ethan: How Does Very-Long-Baseline Interferometry Allow Us To Image A Black Hole?
“[The Event Horizon Telescope] uses VLBI. So what is interferometry and how was it employed by [the Event Horizon Telescope]? Seems like it was a key ingredient in producing the image of M87 but I have no idea how or why. Care to elucidate?”
If it were easy to network radio telescopes together across the world, we’d have produced an image of a black hole’s event horizon long ago. Well, it’s not easy at all, but it is at least possible! The technique that enabled it is known as VLBI: very-long-baseline interferometry. But there are some critical steps that aren’t very obvious that need to happen in order for this method to succeed. Remarkably, we learned how to do it and have successfully employed it, and the Event Horizon Telescope marks the first time we’ve ever been able to get an image with a telescope that’s effectively the size of planet Earth!
Come get the incredible science behind how the technique of VLBI enabled the Event Horizon Telescope to construct the first-ever image of a black hole’s event horizon!
Could All Our Scientific Knowledge Come Tumbling Down Like A House Of Cards?
“Now, think about what would be required to do today to tear down one of our leading scientific theories. It’s not as complicated as you might imagine: all it would take is a single observation of any phenomenon that contradicted the Big Bang’s predictions. Within the context of General Relativity, if you could find a theoretical consequence of the Big Bang that didn’t match up with our observations, we’d truly be in store for a revolution.
But here’s the important part: that won’t mean that everything about the Big Bang is wrong. General Relativity didn’t mean everything about Newtonian gravity was wrong; it simply exposed the limit of where and how Newtonian gravity was successful. It will still be accurate to describe the Universe as having originated from a hot, dense, expanding state; it will still be accurate to describe our observable Universe as being many billions of years old (but not infinite in age); it will still be accurate to talk about the first stars and galaxies, the first neutral atoms, and the first stable atomic nuclei.”
There are a great many people out there who absolutely cannot wait for the day where one of our greatest scientific theories is demonstrated to be wrong. Where an experiment or observation comes in that cannot be reconciled with our leading ideas of how the Universe works. At last, perhaps an unintuitive part of our existence, like relativity or quantum mechanics, might be replaced with something that’s a closer approximation of our actual reality. But that won’t invalidate what we already know; it will merely extend it.
Scientific revolutions aren’t what most people think, but they are going to come, eventually. Here’s what the revolution will actually look like.
10 Deep Lessons From Our First Image Of A Black Hole’s Event Horizon
“6. Black holes are dynamic entities, and the radiation emitted from them changes over time. With a reconstructed mass of 6.5 billion solar masses, it takes roughly a day for light to travel across the black hole’s event horizon. This roughly sets the timescale over which we expect to see features change and fluctuate in the radiation observed by the Event Horizon Telescope.
Even with observations that span only a few days, we’ve confirmed that the structure of the emitted radiation changes over time, as predicted. The 2017 data contains four nights of observations. Even glancing at these four images, you can visually see how the first two dates have similar features, and the latter two dates have similar features, but there are definitive changes that are visible — and variable — between the early and late image sets. In other words, the features of the radiation from around M87’s black hole really are changing over time.”
I’ve heard some grumbling over the past day that people are unimpressed with the Event Horizon Telescope collaboration’s big reveal. Maybe the image doesn’t look pretty enough for some people; maybe it doesn’t have the sharpness or level of detail that people are used to from observatories like Hubble.
Well, may I please introduce you to science? If you knew what we’ve actually learned by taking this image, you might change your tune. Read this, and see if you’re not impressed now!