akemiiwaya — 2014-06-10T13:27:00-04:00 — #1
Originally published at: http://www.howtogeek.com/190885/misconceptions-about-the-universe/
How fast do you think the universe is expanding? Would you believe that it is expanding faster than the speed of light? YouTube channel Veritasium explains how this is possible in today’s video!
sirraf03 — 2014-06-11T04:48:22-04:00 — #2
Why does he say 98,000,000,000 when he even said the answer is 42?
enthusiast — 2014-06-11T13:29:43-04:00 — #3
My question is "What is the universe expanding into?" What is the universe filling up?
jazzbox35 — 2014-06-11T14:28:20-04:00 — #4
I can see it's handwaving already!
yu0x3 — 2014-06-14T16:57:43-04:00 — #5
@Enthusiast The idea of the argument is that the universe is expanding, not expanding into anything. Take the real numbers -- if you multiply everything by two they result still is the real numbers. Same with the universe. If it is infinite, then you can make everything in the universe move twice as far away from anything else, but you don't need more space than before -- twice infinity is still infinity.
That said, I'm a Phd Student of Physics and the video still left me puzzled.
ronniesonora — 2014-06-14T22:26:28-04:00 — #6
If the Data doesn't Fit, change the Rules a Bit:
In effect, astronomers are now saying that many of the closer galaxies are red shifted because they are moving away from us, but the furthest ones are blue shifted -- not because they are moving toward us, but -- because they are younger. In other words, since the blue-shift (for-furthest-galaxies) data doesn't fit with the red shift theory, for objects that are supposed to be moving away from us, and since we are not ready to completely dump the Big Bang, then we'll simply change the rules a bit, by saying that the furthest galaxies are blue shifted, not because they are moving toward us, but because they are young, while the red ones are red (not because they are old, but) because they are moving away from us. In other words, they want it both ways.
For if the Universe were indeed expanding, and if the galaxies were all created as the result of a Big Bang, then they would all have formed at about the same time: meaning that the furthest galaxies should have the highest degree of red shift (and actually be red, as opposed to blue). But since they don't, astronomers are now saying that the blue color has nothing at all to do with their motion, but is simply a sign of their age.
And what about this "Dark Energy" and "Dark Matter" that know ones seen or knows anything about!
“Astronomers have a problem. Whenever they study the large scale structure of the universe, it soon becomes clear that the amount of visible matter cannot possibly generate enough gravity to hold together the structures they can see. Things like galaxy clusters and even galaxies themselves ought to fly apart given the amount of ordinary matter they contain.”Something else must be holding these things together. So astronomers have dreamed up the idea of dark matter — mysterious, invisible and non-interacting stuff that fills the universe, generating the gravity necessary to hold everything together.”According to the latest picture of the large-scale structure of the Universe from the Planck space mission, ordinary visible matter makes up just 5% of the total mass/energy of the Universe whereas dark matter makes up 27%. The rest is the even more mysterious dark energy. To make the numbers work, astrophysicists tell us that our galaxy ought to be at least 80% dark matter.”
yu0x3 — 2014-06-16T04:58:27-04:00 — #7
@ronniesonora That's pretty much summing up how science works If your rules cannot explain the observation you (1) recheck the observation (2) try to find a modification or generalization of your rules that still explains prior observations, but also can explain the current observations and (ideally) is suitable to predict effects beyond those already observed, which can then be used to test the new rules. Granted, this "dark energy" thing is indeed unsatisfactory, but frankly, I don't know enough about it to even judge if it is a viable model on its own or just a crutch for being able to fit the data to existing models.
As for the blue-shift: Maybe they just mean that the light we observe now was emitted by those galaxies at a time, when they were still younger? Just a guess though.
Note again: While I'm a physicist, I'm not specialized in astronomical topics. So while I may have an edge in terms of general math/physics background over many astronomy enthusiasts, I certainly can't compete in terms of domain-specific knowledge.
ronniesonora — 2014-06-16T14:24:35-04:00 — #8
Have you very considered the universe may not be as old as they say it is.
The structure of spiral galaxies themselves also tells us that they cannot be any older than (a maximum of) about 200 million years old: much less than the 13-14 billion years that old earth proponents claim. This is because laws of physics dictate that spiral arms should lose their "structure," or spiral arms, in only 4-5 turns, but for some reason they don't. Perhaps this is because they are Young?
They have been looking for this "Dark Matter" that supposed to hold everything together for 2 decades, with the most sensitive instruments they can build and found nothing, nada, zero, zip. You can't find something that doesn't exist. That's my way of looking at it.
They also thought they were going to prove the "Big Bang Theory" by using the large particle accelerator in the world but you guessed it, they found "NOTHING" to support the theory.
system — 2014-06-20T13:27:03-04:00 — #9
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