Showing posts with label Cosmology. Show all posts
Showing posts with label Cosmology. Show all posts
What is a gravitational wave?
What is a gravitational wave? A gravitational wave* is a concept predicted by Einstein's theory of general relativity. General relativity states that m…
Read more »
If scientists can't see dark matter, how do they know it exists?
Q.If scientists can't see dark matter, how do they know it exists? Ans. Scientists calculate the mass of large objects in space by studying their motion…
Read more »
Why does aurora take different shapes?
Scientists are still trying to answer this question. The shape of the aurora depends on where in the magnetosphere the electrons came from and on what caused…
Read more »
Types Of Galaxies
Many different types of galaxies exist. The different types of galaxies not only appear different, but have different evolutionary histories as well. The thre…
Read more »
Is there any difference between antimatter and dark matter?
Anonymous asked :Is there any difference between antimatter and dark matter? Answer: Anti matter is just like normal matter only the sign of certain propert…
Read more »
Quranic Explanation of Pulsars & Black Holes
Neutron stars are remnants of exploded stars. As more matter falls into a neutron star its mass increases; and as its mass increases its gravity in…
Read more »
Quranic Explanation of Big Bang and Big Crunch
After the Big Bang the universe was primarily Hydrogen, Helium and a tiny bit of Lithium. However when a gas is too hot it becomes ionize…
Read more »
Quranic Explanation of Singularity
All stars will eventually die. They will either directly collapse on themselves and become black holes, or their remnants will merge with other stars that …
Read more »
Q: What is dark matter and why is it important to our understanding of the universe? - Predrag
Dark matter is matter that is invisible to our normal methods of observing matter in galaxies, yet it still has gravitational effects on visible matter. No on…
Read more »
Q: I have a question which has bothered me for quite a number of years and I just have no one to turn to ask. I hope that you can take a few minutes to help me understand. My question has to do with the basic structure of the universe. My understanding is that most physicists buy into the big bang theory - as supported by Hubble's observations of the red light shift indicating that the universe is constantly expanding. However, to put this concept in terms that I can understand, this would mean that from the moment of the big bang to now, the universe would constantly expand from a given point and that all matter would travel outward from that point at some particular speed - as with all explosions. After several billion years, this would create something of a balloon-like structure - relatively empty at the center - but with most matter falling within a certain zone at a constantly expanding radius from that central point - and allowing for differential speeds, collisions, etc. - a fuzzy balloon perhaps. This is the only mechanism I can understand that proves the red light shift is universal. However, it's also my understanding that when the galaxies have been mapped, they suggest the structure of the universe is actually more of a non-ending sponge-like structure with strings and clusters of galaxies linked together with gaps in between. This structure would seem to indicate a steady-state universe over a big bang/fuzzy balloon universe. The obvious conclusion is that the observable universe is completely at odds with the theoretical concept of the big bang. Is there something that ties these two concepts together? Or, if the observation of the sponge-like nature of the universe is correct, is there something fundamentally wrong with the big bang concept? - jeffrey
Yes, it's hard to initially grasp this, but the particular issues you're concerned about actually work out fine in the current picture. Let's loo…
Read more »
F.A.Q's:Cosmology and Astrophysics
What happened at or before the Big Bang? Was there really an initial singularity? Does the history of the Universe go back in time forever, or only a fi…
Read more »