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Universe's Dark Ages May Not Be Invisible After All
StartsWithABang writes: The Universe had two periods where light was abundant, separated by the cosmic dark ages. The first came at the moment of the hot Big Bang, as the Universe was flooded with (among the matter, antimatter and everything else imaginable) a sea of high-energy photons, including a large amount of visible light. As the Universe expanded and cooled, eventually the cosmic microwave background was emitted, leaving behind the barely visible, cooling photons. It took between 50 and 100 million years for the first stars to turn on, so in between these two epochs of the Universe being flooded with light, we had the dark ages. Yet the dark ages may not be totally invisible, as the forbidden spin-flip-transition of hydrogen may illuminate this time period after all.
Negative matter?
is not scientific news, nor does the link point to any academic results. "Ask Ethan" is simply a popular-scientific discussion of results already known. So no News for Nerds, and hardly any Stuff that Matters, IMHO.
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
Thanks for posting. I'll check it out later.
Sometimes, like in the case of the Big Bang, there is no way to test it, so it will forever be speculation.
Testable predictions have been made, tested, and new ones continue to be made.
When a critical element of science, namely testing one's hypotheses is missing, it makes me very unwilling to consider what's being practiced as being "science".
Trying to pretend testing of hypothesis doesn't exist and rebranding something people don't like (e.g. dark matter), isn't practicing science either.
The forbidden Hydrogen spin-flip-transition was first banned at the Olympic Games of 13,299,999,996 BC due to a string of injuries. It will be interesting to see if they can pull it off, although the judges may not be impressed by such an illegal maneuver, which will almost certainly result in an automatic disqualification. Still, they are choosing to make a statement of validity of the maneuver, even at the expense of a possible gold medal. Riveting. Simply riveting.
Turtles. Billions and billions of turtles.
And exactly one pony.
Yet the dark ages may not be totally invisible, as the forbidden spin-flip-transition of hydrogen may illuminate this time period after all.
As long as this forbidden transition involve invoking Nyarlathotep, embracing Shub-niggurath and signing the book of Azathoth, I'm up for it. It's bound to work out okay this time.
We speculated the Sun contains helium, we tested that in the 19th century. Why can't we use the same methods for other stars, and by extension, everything?
How is it "dark" when the universe is flooded with the CMB? I suppose no new light is being generated during the period, but literally everywhere was basking in the glow of the then far more energetic then now CMB.
We speculated the Sun contains helium, we tested that in the 19th century. Why can't we use the same methods for other stars, and by extension, everything?
We tested that? Did someone go to the Sun, breathe some solar matter in, and talk in a squeaky voice? I think you mean we tested a test of a test of a test that seems to point toward the likelihood of the Sun containing helium, and that's the best guess we have.
Islam is incompatible with Western Civilization - why are we tolerating it?
Banning Mosques is cultural self-defense.
Actually, intellectual property restrictions might be leading us more into a dark age...
In the free world the media isn't government run; the government is media run.
There is a name for your complaint:
https://en.wikipedia.org/wiki/Duhem%E2%80%93Quine_thesis
We thought (hypothesis) that space expanded from everywhere.
We predicted a cmb.
We designed experiments to observe cmb.
The evidence rules out expansion from a single point.
Have gnu, will travel.
You mean cultural suicide. After all, it violates the freedom of religion, which is absolutely vital for the marketplace of ideas to exist. That marketplace is the essence of Western Culture, underlaying every currently reigning local ideas.
The only thing mosques do is give the local populace a chance to copy whatever good ideas Islam might have, and of course the other way around. And the only ones it threatens are those who are on top in current status quo and wish it to remain.
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
Hell, yes, just look at Xtians in the USA trying to shut things down because it's not bible learning.
There's fuck all difference between their actions because the problem isn't the faith, it's what they do with it and the fact that it IS only faith. Ergo used to "justify" any and all atrocities that they wanted to commit.
Can someone explain "high-energy photons." The way I understand physics if you add energy to something it moves faster. Photons travel at one speed. The only other option is for them to appear to add mass to themselves when energy is applied. Photons don't have mass apparently. So what are the properties of a high energy photon and how is the energy not expressed as speed?
We thought (hypothesis) that space expanded from everywhere.
We predicted a cmb.
We designed experiments to observe cmb.
You have that backwards. Igor Novikov—of the Novikov self-consistency principle fame—and another Soviet scientist (whose name escapes me) theorized the existence of the CMB in the mid 1960s. However, it was actually discovered accidentally and incidentally in 1964 at Bell Labs in New Jersey by Penzias and Wilson. They were working on a large and very sensitive radio antenna which—after trying to eliminate all known interference—they were still receiving an unknown and mysterious hiss. It wasn't until later that the hypothesis of the existence of the CMB was paired with the already present evidence. They won the Nobel Prize for Physics in 1978 for their discovery.
The evidence rules out expansion from a single point.
I'm not sure the CMB does *that*, exactly. However, there are a growing number of scientists who question the inflationary model.The Ekpyrotic Unvierse Model is one such example of a non-inflationary model. Also, Laura Mersini-Houghton has produced some interesting and testable hypotheses about a competing model to the Big Bang..
No. We looked at the sun. Helium is something we can see, though, not with our eyes.
You see, beyond the basic blackbody radiation (Which is purely due to matter radiating heat), each atom glows at specific wavelengths - this happens when an electron moves to a lower energy state (Think: smaller orbit), and emits a photon at the energy level that corresponds to the difference. Every atom has its own set of wavelengths that it emits - this is called the emission spectrum, and if you stretch out the spectrum of a point of light, you can see bright spots that correspond to this emission spectrum.
Additionally, each atom has a set of wavelengths that it highly efficient at absorbing. These appear as darker spots when you spread out the spectrum of a star. These are called absorption spectrum, and they are unique to each element.
Analyzing the emission and absorption spectrum of the Sun showed that it was largely made up of a gas that hadn't been discovered, because there were strong emission and absorption lines that corresponded to an element we hadn't yet discovered. This gas was named "Helium", after the Greek word "Helios", meaning the sun.
A number of years later, knowing that there was strong evidence of its existence, chemists managed to isolate Helium in the lab, and ran tests on it to measure the properties of Helium's spectrum, and it matched to what we saw in the Sun.
This is how we know the Sun is made of Helium.
You're.... you're not serious, are you?
That's Aricebo Observatory, and it is a real live transmitter/receiver - the largest in the world.
And, yes, parts of GoldenEye were filmed there - though, it doesn't actually fill with water.
Correction:
This is how we know the Sun is^W made^W of^W contains some Helium. (And what proportion.)
I think we've pushed this "anyone can grow up to be president" thing too far.
So, do you think the Golden Gate bridge is also a prop and fictional?
After all, it too has been in a James Bond movie.
Here's something to help you out, just look up Aricebo Observatory. It's probably the single most famous radio telescope/observatory in all of science. They've even done documentaries on it. Just look through the catalog of old NOVA episodes. Heck, there's even been research done on the positive impact it's had on the local wildlife by creating a rather interesting location where other human activity is banned.
Just because Hollywood makes up a lot of B.S., it doesn't mean that everything, even if it's cool, is fictional.
Just wondering. Would nighttime on Mars or the dark side of the moon have a similar light level compared to Earth?
When we send various probes to other planets, is the photography entirely reliant on light reflected from the sun or is there enough light to see the dark side as well?
A link to medium.com! And who is the author? Well none other than Ethan Seigel
Every, single, fucking, day.
Whoops. Didn't mean to imply that it was, but I clearly did. Yeah. The sun is about 71% hydrogen, 27% helium, 1% oxygen, and a smattering of a few other elements.
You're.... you're not serious, are you? That's Aricebo Observatory, and it is a real live transmitter/receiver - the largest in the world.
No, it is only the largest single-aperture radio telescope. The largest is the VLA.
You mean cultural suicide. After all, it violates the freedom of religion, which is absolutely vital for the marketplace of ideas to exist. .
No, freedom of religion is not necessary. What we can't have is enforced religion, which usually comes with lots of limits on "allowed ideas". Abolishing religion completely merely disallows discussions about "gods", you can still have all the interesting controversial scientific ideas we have enjoyed in the past.
I see your negative matter and rise one inverted mass anti-gravity negative antimatter
, you can still have all the interesting controversial scientific ideas we have enjoyed in the past.
Unless power is given to the numerous types that try to brand specific science theories they dislike as a "religion."
Don't try to deflect the blame. It is null hypothesis p-values.
Marketing Dept. Sounds too much like invented matter.
Wonderfully written post. I just want to point out that the way you relate the history, it's tautological that the Sun contains helium. After all, we named the element after the observations of the Sun.