Physicists Discover That Gravity Can Create Light (universetoday.com) 109
Researchers have discovered that in the exotic conditions of the early universe, waves of gravity may have shaken space-time so hard that they spontaneously created radiation. Universe Today reports: a team of researchers have discovered that an exotic form of parametric resonance may have even occurred in the extremely early universe. Perhaps the most dramatic event to occur in the entire history of the universe was inflation. This is a hypothetical event that took place when our universe was less than a second old. During inflation our cosmos swelled to dramatic proportions, becoming many orders of magnitude larger than it was before. The end of inflation was a very messy business, as gravitational waves sloshed back and forth throughout the cosmos.
Normally gravitational waves are exceedingly weak. We have to build detectors that are capable of measuring distances less than the width of an atomic nucleus to find gravitational waves passing through the Earth. But researchers have pointed out that in the extremely early universe these gravitational waves may have become very strong. And they may have even created standing wave patterns where the gravitational waves weren't traveling but the waves stood still, almost frozen in place throughout the cosmos. Since gravitational waves are literally waves of gravity, the places where the waves are the strongest represent an exceptional amount of gravitational energy.
The researchers found that this could have major consequences for the electromagnetic field existing in the early universe at that time. The regions of intense gravity may have excited the electromagnetic field enough to release some of its energy in the form of radiation, creating light. This result gives rise to an entirely new phenomenon: the production of light from gravity alone. There's no situation in the present-day universe that could allow this process to happen, but the researchers have shown that the early universe was a far stranger place than we could possibly imagine.
Normally gravitational waves are exceedingly weak. We have to build detectors that are capable of measuring distances less than the width of an atomic nucleus to find gravitational waves passing through the Earth. But researchers have pointed out that in the extremely early universe these gravitational waves may have become very strong. And they may have even created standing wave patterns where the gravitational waves weren't traveling but the waves stood still, almost frozen in place throughout the cosmos. Since gravitational waves are literally waves of gravity, the places where the waves are the strongest represent an exceptional amount of gravitational energy.
The researchers found that this could have major consequences for the electromagnetic field existing in the early universe at that time. The regions of intense gravity may have excited the electromagnetic field enough to release some of its energy in the form of radiation, creating light. This result gives rise to an entirely new phenomenon: the production of light from gravity alone. There's no situation in the present-day universe that could allow this process to happen, but the researchers have shown that the early universe was a far stranger place than we could possibly imagine.
"Discover" is a big word (Score:5, Informative)
"This is a hypothetical event" (Score:2)
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The Bible says that God created light, and then created the firmament.
That is the opposite of what the physicists are saying.
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Actually, not. In the beginning of the universe the only element was hydrogen. It coalesced into the first star, then when it exploded it created the heavier elements. Firmament could not be said to exist until elements heavier than hydrogen were created. Interstellar hydrogen would not be considered firmament.
Since the gravity waves preceded the stars, it was the beginning of what might theoretically be light.
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Actually, not. In the beginning of the universe the only element was hydrogen.
Actually the H:He ratio was like 3:1 at the beginning of the universe. The observed H:He ratio was one of the evidence supporting the Big Bang theory.
Re:In Science We Trust. (Score:4, Informative)
> Firmament could not be said to exist until elements heavier than hydrogen were created. Interstellar hydrogen would not be considered firmament.
This seems conveniently arbitrary...
=Smidge=
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"Firmament could not be said to exist until elements heavier than hydrogen were created."
Because you need this "fact" to have your argument. Somehow I don't think the originators of these lies knew what the elements were, considering they believed "heaven" was a physical place.
Big Bang Nucleosynthesis (Score:4, Informative)
Actually, not. In the beginning of the universe the only element was hydrogen.
That's just not true. One of the huge successes of the Big Bang model was its prediction for the relative abundances of the light elements - hydrogen through to lithium - that were formed directly from the quark-gluon plasma a few seconds to minutes after the Big Bang. It's called Big Bang Nucleosynthesis [wikipedia.org].
However, in the beginning, we usually assume that the universe was pure energy and that energy coalesced to form matter so arguably the biblical order is what we think: light/energy and then matter. However, that is very much an assumption since we have no clue what the initial conditions of our universe were. For example, a very unsatisfying way to solve the matter/antimatter imbalance in the universe would be to just start the Big Bang with a lot of matter in the initial state.
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Except there wasn't light per se. There were photons, to be sure, but the ionized plasma that dominated the early universe (before around 380,000 years after the Big Bang) meant) meant that photons would have been absorbed, re-emitted and effectively scattered, making the early universe opaque. It wasn't until sufficient electrons had been captured by atomic nuclei that the universe became transparent. The CMBR is the remnant of that phase transition, when the universe went from opaque to transparent, so no
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Except there wasn't light per se. There were photons, to be sure, but the ionized plasma...
Plasma? That was not around until minutes after the Big Bang. I'm talking way back at the start - we can push the clock back to around 10^-13s after the start where the energies were comparable to the LHC collisions and there was no plasma because there were no protons or neutrons, only a quark-gluon plasma which is a very different beast to your ordinary plasma.
The usual model is that the Big Bang started with no matter at all, just bosonic energy and our fermionic matter formed from that. So saying th
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Re:In Science We Trust. (Score:5, Insightful)
Yep, the Bible also says God created the Universe in 6 days. Them are some mighty long 6 days, I deem them not sufficient to bury and fossilize all those dinosaur bones. There are also two different versions of creation in Genesis. The order in which things are created differs between them. Adam and Eve apparently did the naughty enough to pop. the Earth without causing genetic abnormalities. Then there is the talking snake.
Let's get to the New Testament. There are different versions of Christ's resurrection depending upon which book you read. They cannot even agree on when and where Jesus met his disciples after the big event. Jesus predicted the coming Kingdom of Heaven before his generation died off. Near as we can tell, that didn't happen.
Just add to the silliness, the Apocalypse was talking then then current Roman empire, not about the present day. And if you read it carefully, a lot of retribution is handed out, not something the current Christian apologists which ascribe to the God of Love. But then the current Christian apologists wanted a border wall to keep out those little brown people from south of the border and they are big believers in guns...lots of guns. Too bad we cannot put Jesus on the border. When a refugee wants to enter the U.S., we ask him, "What should do, Lord?".
Re:In Science We Trust. (Score:4, Informative)
Mostly true, though your account lacks any sort of philosophical charity.
For instance the bible isn't a book, it is a collection of books and none of those books are original or written by the supposed original participants. Believing in its literal truth cover-to-cover is a fringe thing, not the typical case. The more common idea is that God will have made sure it contains what you need within it. The method of finding what you need varies with Catholics believing the clergy will be divinely inspired and inspire you in turn and most other Christians believing in a more personal relationship with a 'living God' such that the individual will be guided to what they need and the understanding of the material they need at the time they need it.
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"The more common idea is that God will have made sure it contains what you need within it. "
More common if you say so, yet equally stupid.
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Not really. Normally the negative case is the default because there are nearly limitless possibilities which could exist but only one which does. But when it comes to a deity the negative covers only ONE possibility with no supporting evidence. Granted, each specific possibility that is ruled out adds to the probability of the door you've already chosen but that is true for the doors others have chosen as well and frankly there are so many possibilities here we could rule out options for millenia without th
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I don't think the literalists are a fringe case. Or at least not in America. They might be a minority but they're also big enough to have significant sway in politics and society.
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Not really, you mostly find them in the caricatures painted when those of one political ideology are trying to pretend their opposition are a homogenous group. It is really difficult to oppose millions of positions which disagree with yours but much easier to bash down a single irrational strawman. You also find them in the sociopaths who've bought into that strawman and are trying to play that role to side with that political opposition of course.
You should see the last debate on evolution I participated i
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Yep, the Bible also says God created the Universe in 6 days. Them are some mighty long 6 days, I deem them not sufficient to bury and fossilize all those dinosaur bones.
People stopped thinking the word "day" in the first chapter of Genesis meant a literal 24-hour solar day a couple thousand years ago (it was pretty easy to figure out, since the sun wasn't created until the fourth day). Then fundamentalist Christians brought it back.
There are also two different versions of creation in Genesis. The order in which things are created differs between them.
Not really. Chapter 2 of Genesis is just a more detailed story of the creation of humans. The only difference is whether or not plants had started growing yet when humans were created; Chapter 2 doesn't mention most of the things created in Chap
Re:In Science We Trust. (Score:5, Insightful)
"People stopped thinking the word "day" in the first chapter of Genesis meant a literal 24-hour solar day a couple thousand years ago (it was pretty easy to figure out, since the sun wasn't created until the fourth day). Then fundamentalist Christians brought it back."
LOL the suggestion that people were "thinking" when and after these lies were made up. The originators of these myths didn't stop to consider that "day", in their primitive language, wouldn't be suitable. They didn't even understand that a "day" was the interval defined by the rotation of the earth, which they didn't realize wasn't flat.
Stupidity heaped on stupidity continues with the people who try to make intelligent excuses for it today.
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You don't need to know anything about the shape of the earth or the nature of the cosmos to tie "day" and "sun" together.
The entire concept of "day" is literally "the period of time when the sun is in the sky". Without a sun, the concept has no meaning. Except, arguably, "the period of time between extended rests".
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And since this is Slashdot, you should see the expression "back in my day" pretty often. Do you think someone who writes that is talking about some specific 24-hour period?
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Myths and parables are not lies, and neither are mistakes in theories by people who had no way to understand otherwise.
So, if I say "Back in my day I had to walk two miles
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Religion does not depend on reality in any way, since it describes the unreal.
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They didn't even understand that a "day" was the interval defined by the rotation of the earth, which they didn't realize wasn't flat.
So, around which time was the Bible invented/written/made up?
I mean: as a scientific objective hater of people who read "holy bocks" and calls a myth a lie (seriously? a myth is a lie? - get a dictionary or a thesaurus), you do not even know who "made all this up" and what they already had as scientific knowledge?
I would bet a random Sumerian priest knew more about the univer
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Not really. Those are two different creation stories coming from different traditions saying different things about the nature of existence and the relationship between people and the creator.
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I'm not really sure which people are worth:
a) religious nut cracks that take a "holy book" written by savages literally
- or -
b) modern day morons who take a "holy book" written by savages literally and try to make an "scientific excursus" why it can not been taken literally
Surprise, surprise: most believers - regardless what "holy book": do take the "historical transmitted stories" _not_ literally. They perfectly well know: they are stories.
I for my part put both, followers of a) and also followers of b) i
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But then the current Christian apologists wanted a border wall to keep out those little brown people from south of the border
Just so that you know... cheerleading or being indifferent to lawless illegal invasion is an outlier political position.
According to PEW, who actually asked, the wall is favored by just 42% of Americans. [pewresearch.org]
Looks like you're on the outlying province of race relations.
Re:In Science We Trust. (Score:5, Informative)
>And God said, “Let there be light,”a and there was light. And God saw that the light was good, and He separated the light from the darkness. God called the light “day,” and the darkness He called “night.”
This almost sounds like this entity has now created the Sun, maybe? Well, it gets a bit confusing later on, but never mind that. We have our first counterfactual! The Sun actually existed long before the planets formed.
>Then God said, “Let the earth bring forth vegetation: seed-bearing plants and fruit trees, each bearing fruit with seed according to its kind.” And it was so. The earth produced vegetation: seed-bearing plants according to their kinds and trees bearing fruit with seed according to their kinds.
Hang on there, did we just create trees before animals? And we have our second counterfactual! Trees evolved during the Devonian period, which lasted from 419 million to 358 million years ago. Vertebrates evolved during the Cambrian Period, roughly 530 million years ago. But what's a 100 million years among friends?
>And God said, “Let there be lights in the expanse of the sky to distinguish between the day and the night, and let them be signs to mark the seasons and days and years.
So this is just not even wrong. Somehow, first this deity "called the light “day,” and the darkness He called “night.”"
>God made two great lights: the greater light to rule the day and the lesser light to rule the night. And He made the stars as well.
So... that would mean that the Sun and the Moon, were created after "night" and "day", somehow? Except that... those were both created long, long before any sort of life arose on this planet. Let's call this counterfactual number three.
>And God said, “Let the waters teem with living creatures, and let birds fly above the earth in the open expanse of the sky.”
Wrong again. Birds evolved around 150 million years ago during the Jurassic period, whereas the earliest known fish evolved during the Cambrian period, around 530 million years ago. I've lost count of how many counterfactuals we have so far... and we're still on page 1.
>And God said, “Let the earth bring forth living creatures according to their kinds: livestock, land crawlers, and beasts of the earth according to their kinds.” And it was so. God made the beasts of the earth according to their kinds, the livestock according to their kinds, and everything that crawls upon the earth according to its kind.
Well this is just getting tedious now, but just as an example: Insects evolved over 400 million years ago during the Silurian period. I hope you'll agree, those would be things that "crawl upon the earth", and they predate birds by quite a bit.
Look, if you want to talk about the bits of this book that, in retrospect, seem somehow to coincide roughly with what is actually true, then you'll also have to account for the much larger number of couterfactuals that one finds here. So either this book is the divinely inspired Eternal Truth of the Word of Some God, one who happens to have quite a rich cosmic sense of humor and likes telling lies to see who believes time..... or, it exactly what it looks like: an anthology of Bronze Age myths and legends.
But given the choice between reality and your favorite book, you will chose your book every time, won't you?
Re: In Science We Trust. (Score:2)
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But why is it that all the world's religions are forever patching up their dogmas to fit with actual observed reality, rather than the other way around? When was the last time
Re: In Science We Trust. (Score:2)
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But yeah, I'm sure every word of this extremely beautiful book really is true... somehow! After all, it's all about the context, isn't it
https://www.youtube.com/watch?... [youtube.com]
Re: In Science We Trust. (Score:2)
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Re: In Science We Trust. (Score:2)
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I found this YouTube channel a couple weeks a
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But given the choice between reality and your favorite book, you will chose your book every time, won't you?
I doubt many people on the planet would consider the books you talk about "their favourites". And most people on the planet, regardless which religion they come from, have scientific education.
That means they perfectly well know that the "creation myths" are creation myths, and not scientific facts.
The only people who believe the creation myths are scientific "facts" are people like you. You establish
Re: In Science We Trust. (Score:2)
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Exactly, there is no point in arguing with a dumbass like you :D
But feel happy with your idiotic idea that "believers" consider the stories in their "holy books" as scientific facts - lol.
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ME: You an idiot, and aguing with you is clearing a waste of time.
YOU: I know you are, but what am I???
You would lose a battle of wits against a paperclip. Nice try anyway. Don't hurt yourself, OK?
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40% of Americans Believe in Creationism
https://news.gallup.com/poll/2... [gallup.com]
Don't worry. If you're feeling stupid right now, that's just because you are.
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This is a mildly interesting topic for me. I am definitely not a "churchy" type person, nor do I believe in what any of the Churches teach; however, the book of Genesis is interesting. If you look at it with slightly out of focus vision, the creation story does make sense. The order of operations is generally correct: light/matter/basic life/primitive life/advanced life. It seems extremely accurate for a bunch of ignorant sheep herders. Sure, with our "advanced" knowledge, we can pick apart the exact words
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As for the "some people" who "actuall
light vs sun (Score:2)
light and darkness in the bible (and in science) are concepts independent of the sun and stars. Presumably when Genesis was written, people had seen fire, which shines light independently of the sun. They must also have noticed lightning.
In the new testament, light is associated with truth, and darkness with falsehood. It is more fundamental entity than the sun. And certainly the bible would not want to give too much importance to th
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discovered? (Score:3)
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Prove is funny word with respect to physical theories. Generally we can only support them up to a certain percentage. Even that does not entail that the phenomenon we see is not caused by something else. Disproving them is much easier, we just look for a phenomenon at discord with the theory.
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Indeed. Strictly speaking prove doesn't even make sense. Science is a framework for building models, not realities. What you establish is that the model successfully predicts various aspects of reality within a margin of error with the correct constraints applied. A different and incompatible model may work with different constraints and there is nothing to indicate there isn't more than one possible coherent model.
With the physical sciences you have external and objective physical reality to measure agains
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"Disproving them is much easier, we just look for a phenomenon at discord with the theory."
But why persist in current paradigms when they lead some scientists to call vacuum energy âoethe worst theoretical prediction in the history of physicsâ? (See "The Cosmological Constant Is Physicsâ(TM) Most Embarrassing Problem", Scientific American, February 1, 2021)
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Something I don't understand (Score:3)
Surely gravity at the point of creation was virtually infinite as makes no difference as per the singularity of a black hole - so how could the universe expand? Does there mean theres some force that exists that can overcome even the most powerful gravitational field? Where is it today?
Re: Something I don't understand (Score:5, Informative)
Re: Something I don't understand (Score:5, Insightful)
or in other words "they have no fucking idea but are happy to make some guesses."
If you've got a better guess, which is either simpler or has stronger predictive power, there is a gold medal in Stockholm waiting for you.
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Did you leave out the step where you have to sell Electric Universe theory to the modern-day equivalent of epicyclists married to their Standard Models?
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The theory is a mathematical model that predicts measurements that we can make today, but the model cannot be evaluated for any time, only for time AFTER a certain time. You are trying to ascribe characteristics based on a model that is known not to work at the time you are considering.
Re: Something I don't understand (Score:2)
Do you have an english translation for that gibberish?
Re:Something I don't understand (Score:5, Interesting)
Do you understand what a singularity actually is? It isn't an object, it's a point at which equations break down and start spewing it impossible answers. The reason what lies beyond the event horizon of a black hole is called a singularity is because General Relativity cannot account for conditions of apparent infinite density. The same basic notion applies to the Big Bang, which points to an epoch of seemingly infinite density. The problem at its core is that we have a very good classical explanation for gravity, but we lack a quantum explanation, which is why GR breaks down at such points. Perhaps one day, when we do have a renormalizable explanation for gravity, those singularities will disappear and in their place will be an explanation for what happens in such regions of space-time.
As to gravity, it is the weakest of the fundamental interactions. To demonstrate that easily, take a pen, hold it up a foot off your desk, and then drop it. Gravity is so astonishingly weak that the pen will bounce because gravity cannot overcome the strong interaction. So while gravity can have the most spectacular effects, like black holes and moons orbiting planets, it is still far weaker than the other interactions.
And yes, space can expand faster than the speed of light. The speed of light as a limiter only applies to the propagation of fields *in* space (in other words, all matter and energy). It's underlines one of the biggest questions in cosmology; is the open universe open, flat or closed. If it is open then the expansion rate will increase. If it is flat the expansion rate may decline but will never reach 0 or reverse. If it is closed at some point the universe will begin to contract and end in a Big Crunch. Thus far, all evidence points to a positive expansion rate, and more telling, to that expansion rate increasing. In other words, we live in an open universe that will continue expanding until everything dissipates into a dissipated fog of elementary particles and quantum fields, where likely even protons will eventually decay into their constituent quarks and gluons, a sort of low energy mirror image of the earliest universe.
And it's not for physicists trying to find sufficient matter to produce a closed universe. After all, if there was enough mass in the universe, gravity might act as a brake on the expansion. But alas, it does not appear that there is anywhere near enough matter to have ever had any capacity to overcome the expansion at any point since the Big Bang.
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Gravity is so astonishingly weak that the pen will bounce because gravity cannot overcome the strong interaction.
I think you mean electromagnetism.
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The problem at its core is that we have a very good classical explanation for gravity, but we lack a quantum explanation, which is why GR breaks down at such points.
Hm. The Classical explanation for Gravity seems to me to be ... utter garbage. The theory was created through observations, which are accurate, but only done from one perspective. If I have a cylinder in my hands and I hold it at a certain angle, you will see only a rectangle. If I hold that exact same cylinder at another angle, you will see only a circle. Both the rectangle and the circle are "accurate" observations, but bely the true nature of the object, which is indeed a cylinder. Classical science saw
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Strictly speaking: if a black hole is big enough, and that is true for all of them that we can observer, they all expand.
And from an inside point of view: there could be a whole universe inside and no one on the outside would know about it.
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Surely gravity at the point of creation was virtually infinite as makes no difference as per the singularity of a black hole - so how could the universe expand?
The topic you are looking for is 'inflation'. The Universe expanded faster than the speed of light for a "period of time" during the very early stages of the Universe (according to current theories).
I guess you could say the original Black Hole kind of exploded. I do not think anyone knows WHY it "exploded".
Physicists THEORIZE That Gravity MAY Create Light (Score:2)
Re:Physicists HYPOTHESIZE That Gravity May Crea... (Score:3)
FTFY
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I have a bigger issue with them saying gravity *alone* created light, but right before that they state that the extreme gravity waves *and* large electromagnetic field produced the light.
They got their exmpl of parametric resonance wrong (Score:5, Informative)
Parametric resonance would be if you stood on the swing and alternatively stood tall and kneeled in the correct rhythm.
Difference is that plain resonance can excite the system from a standstill, whereas parametric resonance can only amplify a pre-existing oscillation (i.e. it needs an initial push).
Nice example is the Botafumeiro [youtube.com] in Santiago de Compostela: they have to give it an initial push, or else rhythmically pulling the rope would do nothing (or take much longer).
In the beginning (Score:1)
In the beginning, there was light! Turns out the bible is true after all. /s
What is Quasar? (Score:1)
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An early brand of TV? Quasar TV [wikipedia.org]
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Yes.
"Weak" gravitational waves (Score:3)
Gravitational waves are typically weak when they get to us from very far away. But I'm not sure if that makes them inherently weak. They're typically produced by the interaction of extremely heavy objects at extremely high speeds, and then they travel an extremely long distance to get to us. That's a lot of extremes that are in both the numerator and the denominator of however we define wave strength. I wouldn't consider the waves weak if their origin was only a few light years away.
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Gravity is Weak (Score:3)
They're typically produced by the interaction of extremely heavy objects at extremely high speeds
That's not true. All massive objects under acceleration produce gravitational waves, just like all accelerating charged objects produce EM waves. For example, Earth orbiting the sun produces gravitational waves. The reason that we have only seen gravitational waves from colliding black holes and neutron stars is exactly that gravitational waves are so incredibly weak and we cannot possibly detect the waves emitted by orbiting planets and stars in our very neighbourhood. We need an insanely bright source wi
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Specifically it’s because the waves themselves are not measurable, only the distortion
What are you talking about? The periodic distortion of space-time is the wave just like the periodic distortion of the EM field is a photon.
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What are you talking about? The periodic distortion of space-time is the wave just like the periodic distortion of the EM field is a photon.
No its not. here [caltech.edu] is a good work up of the differences. Specifically while similar to transverse electromagnetic radiation or dipole radiation but instead of a second order derivative term it depends on the fourth derivative of the quadrupole moment.
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Yes, that's because it is a spin-2, or tensor field and not a spin-1 vector field like EM but it does not mean it is not a periodic distortion and that's exactly what you measure. This is why LIGO has two arms.
What part of the Electric or magnetic field is unobservable? Saying all periodic motion is the same is not exactly accurate, especially when a large part is directly unobservable.
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What part of the Electric or magnetic field is unobservable?
An EM field is as "visible" as gravity. You certainly can't see the magnetic field of e.g. a fridge magnet unless you put matter in the way (like iron filings). That's exactly the same for a gravitational field. Indeed, this is how all detectors work - the field in question interacts with the matter in the detect that produces the signal that we then pick up. The EM coupling is much, much stronger than gravity at typical human scales so the effects of EM fields are readily visible while the effects of grav
Awesome.... (Score:2)
Now we just need to reverse the process and create gravity from light
Re: Awesome.... (Score:2)
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Now we just need to reverse the process and create gravity from light
Shoot beams of light parallel to each other from opposite directions.
Re:false claim (Score:5, Informative)
I'm not sure how that implies that at all. The expansion of space is something happening within the universe; it is an intrinsic attribute of space itself, not something external to space. GR predicted it (and Einstein tried to get rid of it by creating a Cosmological Constant to counterbalance it), Hubble observed it and cosmologists like Lemaitre came up with the framework of that expansion, ultimately confirmed through the three major lines of evidence; the Hubble Expansion, nucleosynthesis (the quantities of hydrogen and helium observed that cannot be explained by stellar processes), and of course, the final death knell for the steady state model; the observation of the CMBR, produced when photons were liberated from the ionized plasma stew that had dominated the universe up until about 380,000 years after the Big Bang.
Further, the Inflationary Model, which theorizes a rapid inflation of space in the universe early in its history, invoked to explain the high degree of homogeneity of the universe in any direction one cares to look. Without Inflation, one would expect to see a far more heterogeneous distribution of matter in the universe, but the fact is no matter which way we look, the universe is incredibly isotropic and homogeneous. A rapid inflation in the early universe would lead to a "smoothed out" distribution, which is exactly what we observe.
And finally, all observations indicate the expansion rate is increasing, which is where Dark Energy comes into play as an explanation for that rate of expansion.
Gravity cannot explain the expansion. First of all, it's too weak; Newton's F=GMmR^2 (the inverse square law) means that even massive gravity wells like galaxies, clusters and even superclusters, can't overcome the expansion rate (and cosmologists and physicists spent years trying to find the "missing matter" that could turn the tables on expansion).
The problem with ideas like an external force pulling the universe apart is that these conceive of the Big Bang as an explosion, with a sort of epicenter out of which all matter and energy were blasted away. But that's not how the expansion works. At the Big Bang, every point in space was in the same space, and then began each point began to move away from each other point, with sufficient isotropy and homogeneity that no matter where we look, it looks exactly the same to within 1/10000 a degree of variation. No matter where you point a radio telescope in the sky, the CMBR black body radiation is statistically nearly identical, meaning there is no center, that every point in space is expanding away from each other point.
Even Eternal Inflation, which posits that different "bubbles" of space exited the inflationary phase at different times (the origins of multiverse theory) still posits that these bubbles are separated by vast distances so that there can be no "communication" (field interactions) can occur between these bubbles. They lie so far beyond the horizon of observation (the most we can even see of our bubble is 94 billion light years, though one presumes our universe is actually much larger than that), that we could observe them. The best we can hope for is that minute variations in the CMBR might indicate primordial gravity waves, and hint at the nature of inflation very early on.
Discovering what working classes already know (Score:2)
Perhaps the most dramatic event to occur in the entire history of the universe was inflation.
Having bought groceries recently, I can definitely say that the inflation in America is dramatic.