Posted on 08/17/2016 5:41:51 AM PDT by rickmichaels
If the universe was infinitely old, as we used to assume, then it must be filled with an infinite number of stars and galaxies.
So why is the night sky not completely lit up by the light from these stars?
This question was first asked by the nineteenth century astronomer Heinrich Olbers, and the answer is, because of the age of the universe, not all of the photons have had enough time to reach us yet.
The amount of universe we are able to see is called the observable universe, and according to a pair of astrophysicists, it just got 320 million light years smaller.
(Excerpt) Read more at dailymail.co.uk ...
and it does. At least according to current ways of thinking. This is how we measure distance to stars. Light DOES take a different amount of time to cover different distances and the same amount of time to cover the same “distance” if distance continues to mean anything constant.
That's because there are no old Syfi movies. Syfi is a cable television channel. They say they are a network but they are really nothing more than a video feed of forty percent commercials. Don't let them change our language. It's Sci Fi.
There’s never and “end”...Always something past the “end”, so there would never be an “end”....
...which kinda backs up my #22 response to #16, right?
Sorry, somewhere along the thread I missed your #60.
Gotta tell ya though, most of it was waaaayyyy over my head
Thanks for the tip.
Sorry, go back through that second paragraph and substitute “change in” for every lower case “d” as in “change in x/time” for dx/dt.
Even with all of those starships to park, Marvin is still depressed. The brain the size of a planet and just a parking lot attendant.
If you have not read these books you won’t regret doing so. The author suffers a bit in the storytelling skills but the ideas are a gold mine. Better than Asimov and Bradbury and Heinlein all combined.
and the third book is supposed to be released Sept 20th. I can’t wait!
I thank you and stand corrected.
Now, any recommendations? Maybe a sleeper? Not interested in seeing another crew of one Black, one Asian, one Female, and one Caucasian fighting CGI monsters, or Zombies.
If the universe is 14 billion years old, why is the radius of the universe so much more than 14 billion light years?
Just can’t get my brain wrapped around it.
Appreciate the effort, but it’s pearls before swine.
Oddly, no matter where you are in the universe, you are in the center of the universe. The universe may simply appear larger or smaller.
Ha ha, Galileo!
>> If you keep on going, you end up where you started. Maybe that’s how the Universe works - a celestial Möbius strip. :-) <<
Yes, you do. Non-Euclidean geometry is a bitch.
I think you are seeing into a contradiction, or seeming contradiction. If there was a Big Bang, there would be a “center of the Universe”. If there was such a point one might wonder if that would not be a “preferred frame of reference”. Einstein did not seem to think there would be one and to date all of Einstein’s predictions based on his theory have held up, AFAIK.
“One of those hypotheticals is that the shape of the universe is a torus (donut shape) and the universe is inside. Is that possible?”
Mmmm donuts.
Cixin Liu is a real source of curiosity for me. How in the world did the gummint of China allow a chinese to learn and publish so much about American History and Liberty. According to my understanding of China what he writes about these things would have had him executed.
I suppose as an engineer with an interest in physics as a hobby he could be familiar with the ideas he uses but the level of knowledge he seems to have about theoretical physics is pretty far beyond “hobby”.
Right, Wastoute... but go further, or else you’ll leave Roccus thinking it’s all simply bulls—t.
The fact that they all get the same result is where we get the notion of time dilation from. How can light appear to be traveling the same speed relative to you, regardless of your speed? The answer is that the flow of time changes, too.
OK, let’s make the math simpler and say light travels at 200,000 km/s.
You “chase” the light at 150,000 km/s. So light should now appear to be traveling away from you at only 50,000 km/s, right?
If I’m observing, standing still, you will indeed seem to be losing only 50,000 km/s relative to the speed of light. But to you, time will go by at 1/4 the speed, so in one of YOUR seconds, light will travel four times further, and to YOU, it will still be going at 200,000 km per YOUR second.
Exactly. So the only yardstick in the universe that doesn’t change as you use it is light, it’s speed. I am sure that means profound things but I am just not capable of understanding what they are. The harder I try it seems I will never make that next step. I can almost feel it but I just can’t get there. It’s like the greek guy that was punished by frustration.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.