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"Oddly, little attention was given to an obvious conclusion: if the galaxies are rushing apart, there would have been a time in the past when they were all crun

by jheriko 13y ago

"Oddly, little attention was given to an obvious conclusion: if the galaxies are rushing apart, there would have been a time in the past when they were all crunched together. " I still find this hard to swallow - whilst its obvious as a conclusion, it also feels like it has obvious flaws. Can we not get exactly the same effect from a large universe in which new space and matter is formed in the voids? and don't we need to understand the /actual/ creation of space and matter in totality (v.s. eg creation and annihilation of particles and other 'bits of universe) - its an enormous gap in our understanding and a vital feature of a truly comprehensive theory...

acqq 13y ago
You are not the first that thought about that possibility, there's a lot that we observe that is expected result of the Big Bang and that wouldn't exist otherwise: http://en.wikipedia.org/wiki/Big_Bang#Observational_evidence http://en.wikipedia.org/wiki/Big_Bang#Observational_evidence
jessriedel 13y ago
First, we would expect to see such matter production occuring today, not just in the past. Second, and much more conclusively, we have specific predictions from Big Bang Nucleosynthesis (which was just 20 minutes after the big bang, when the entire universe was as hot and dense as the interior of a star) that match up to observations today with exquisite detail. BBN is perhaps the most stunning underappreciated fact about our world, even amongst physicists.
Sharlin 13y ago
As the article itself mentions, the Big Bang hypothesis did not become an accepted theory just based on the single piece of evidence that other galaxies seem to be receding from ours. Indeed, the term "Big Bang" was originally coined as derogatory by the famous astronomer Sir Fred Hoyle, a steadfast supporter of the competing Steady State hypothesis [1]. Many in the astronomer community found the idea of the universe having a beginning simply preposterous. However, in the end, it was the model that best matched observations, and thus became (perhaps reluctantly on some people's part) accepted. This is how science is supposed to work. [1] http://en.wikipedia.org/wiki/Steady_State_theory http://en.wikipedia.org/wiki/Steady_State_theory
mahranch 13y ago
"don't we need to understand the /actual/ creation of space and matter in totality" Well, there are some hypotheses on what caused the Big Bang in the first place (and as a result, all of space, time & matter) but they are currently relegated to thought experiments. We just don't have the technology yet to test them. There might be some things that could show up in more detailed observations of the cosmic microwave background, things which if found would be suggestive, but the evidence still wouldn't be conclusive. You can google "what came before the big bang" to read up on those hypotheses. Keep in mind that they are thought experiments. Pop-scientists will often talk about those hypotheses like they're fact, but the truth is there's still a long way to go.

by jheriko 13y ago

acqq 13y ago

You are not the first that thought about that possibility, there's a lot that we observe that is expected result of the Big Bang and that wouldn't exist otherwise: http://en.wikipedia.org/wiki/Big_Bang#Observational_evidence http://en.wikipedia.org/wiki/Big_Bang#Observational_evidence

jessriedel 13y ago

First, we would expect to see such matter production occuring today, not just in the past. Second, and much more conclusively, we have specific predictions from Big Bang Nucleosynthesis (which was just 20 minutes after the big bang, when the entire universe was as hot and dense as the interior of a star) that match up to observations today with exquisite detail. BBN is perhaps the most stunning underappreciated fact about our world, even amongst physicists.

Sharlin 13y ago

As the article itself mentions, the Big Bang hypothesis did not become an accepted theory just based on the single piece of evidence that other galaxies seem to be receding from ours. Indeed, the term "Big Bang" was originally coined as derogatory by the famous astronomer Sir Fred Hoyle, a steadfast supporter of the competing Steady State hypothesis [1]. Many in the astronomer community found the idea of the universe having a beginning simply preposterous. However, in the end, it was the model that best matched observations, and thus became (perhaps reluctantly on some people's part) accepted. This is how science is supposed to work. [1] http://en.wikipedia.org/wiki/Steady_State_theory http://en.wikipedia.org/wiki/Steady_State_theory

mahranch 13y ago

"don't we need to understand the /actual/ creation of space and matter in totality" Well, there are some hypotheses on what caused the Big Bang in the first place (and as a result, all of space, time & matter) but they are currently relegated to thought experiments. We just don't have the technology yet to test them. There might be some things that could show up in more detailed observations of the cosmic microwave background, things which if found would be suggestive, but the evidence still wouldn't be conclusive. You can google "what came before the big bang" to read up on those hypotheses. Keep in mind that they are thought experiments. Pop-scientists will often talk about those hypotheses like they're fact, but the truth is there's still a long way to go.