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Computer Simulations Point To the Source of Gravitational Waves (theverge.com)
An anonymous reader writes from a report via The Verge: On February 11th, scientists at the LIGO observatory made history when they announced the detection of the first gravitational waves. A new study says the gravitational waves likely came from two massive suns that formed about 12 billion years ago, or two billion years after the Big Bang. The researcher's calculations have been published today in the journal Nature, and were determined by running a complex simulation called the Synthetic Universe: a computer model that simulates how the Universe may have evolved since the start of the Big Bang. The simulation even includes a synthetic LIGO detector to determine the types of objects that the observatory would detect over time. The Synthetic Universe can also make predictions as it includes a mock-LIGO to chronologically sync when we detected the waves. If the model is correct, we should see LIGO pick up to 60 detections when it begins its next observation run this fall. It could hear up to 1,000 detections annually at its peak sensitivity. The lead study author Chris Belczynski speculates specifically the size of black hole mergers that the LIGO should be able to detect from gravitational waves, a combined mass between 20 and 80 times the mass of our sun, indicating that they're likely from soon after the Big Bang when stars had lower metal content and formed proportionately larger black holes. His model suggests that the ones that collided to make these gravitational waves were stars that formed 12 billion years ago, became black holes 5 million years later, and then merged 10.3 billion years after that.
The practical value is that we finally have a way to probe one of the biggest parts of physics that we don't actually understand, gravity. And it has direct implications for all of the other aspects that we don't understand or have major questions about, such as inflation, dark energy, the unification of relativity and quantum physics, etc. The field has massive potential to further our understanding of physics and the universe that we live in.
And LIGO is only the start. When something like eLISA comes online it'd be like going from the blurry images of Galileo's telescope to an actual astronomical observatory.
Did he just go crazy and fall asleep?
It is still potentially falsifiable, though. Since these formulae are all interrelated you can corroborate that the model matches for related phenomena. Then you can look for edge cases where it might break down and then further refine things.
No, what you do is see something, try to figure out how it might work and model it. At this point you probably have a model that "works" because it fits your observation - not very useful. But then you use it to predict what else you might see. If the prediction matches the next observation, it strengthens the possibility that the model might actually describe something fundamental, more and more so as it gives consistent results over many observations. If the prediction doesn't match, you figure there's something wrong with the model and start again, or you refine the model, and so on and so on.
[Citation needed]
The first actual Viking discovery in the Americas, L'Anse aux Meadows, was not particularly controversial. Yes, there were things dismissed as hoaxes before that, like the Kensington Runestone. That's because they were hoaxes.
The problem wasn't that people "disbelieved" claims of Norse settlement - it's that most people were simply unaware of them. There wasn't a great deal of interest outside of places like Iceland in the history of viking exploration until the early 20th century. Around the start of the 20th century there started being an increasing debate as to whether they referred to real places and if so where they were located. Expeditions really began to find them in the 1950s - Jørgen Meldgaard came extremely close, only about 15km from the site at L'Anse Aux Meadows, while following up on earlier suggestions by Tanner and Munn. The only physical find that Meldgaard found significant wasn't found in Canada or the US at all - it was from Greenland, an arrowhead in a viking settlement that matched Canadian native materials (ramah chert) and styles rather than Greenlandic. The Canadian government had offered significant support for his explorations (the Danish National Museum however was more hesitant, preferring that Meldgaard focus his research more on Native American cultures).
The biggest controvery that arose after Ingestad's excavation at L'Anse Aux Meadows was not people insisting that it was fake, but rather a row between Denmark and Norway as to who gets the credit for discovering it first. Denmark went back and tried to push Meldgaard's role in helping find the location (although he never did find any artifacts), and there was a lot of hostility in the Danish and Norwegian press over the issue (for what its worth, Meldgaard and Ingestad had a friendly relationship)
Did he just go crazy and fall asleep?
I never saw how this differed from the Michelson-Morley experiment, and could equally show the existence of luminiferous ether.
Well, they are different.
The Michelson-Morely experiment was a failure: it was designed to observe changes in the speed of light in different reference frames, but it showed none. And that result changed our understanding of the universe in fundamental ways.
These gravitational-wave observations, and their subsequent simulations, appear to be a success for the theory of general relativity. And that's important too.
If it weren't for deadlines, nothing would be late.
They are making very specific predictions about the number and type of collisions they will detect when LIGO comes back online in the fall. That's pretty much the definition of falsifiable.
love is just extroverted narcissism