That is my understanding.
Experiments which were more than capable of detecting WIMPs, had they existed, spectacularly failed to do so.
That's interesting. Effectively 4 physical co-ordinates to eliminate time uncertainty. Quaternions are an alternative to vectors. But you solve a 3D rotation with 4 co-ordinates. Same thing, I suspect.
I am taking a break from Einstein's Field Equations right now, since my computer speakers have packed up, and headphones just aren't enjoyable. New speakers arrive tomorrow.
Einstein Field Equations - for beginners! - YouTube
On Black Holes.
I dug up the interesting fact a while back that if the Universe was a Black Hole, it would be exactly 13.7 Billion light years radius. The exact current size of our universe.
Schwarzschild radius - Wikipedia
A strange co-incidence. Black Holes become less dense as they get more massive. In fact the mass is proportional to the surface area. Which relates to information on its surface.
Assuming continuous expansion of the universe and negligible addition of mass then the universe was denser than a black hole a few billion years ago???
Something has got to be wrong.
The average density of a black hole is its mass divided by the volume within its Schwarzchild radius.
You might expect that throwing matter over the event horizon would increase the average density of a black hole, but it actually decreases it.
Physicists have discovered that the radius of a black hole doubles when its mass doubles. The volume of a sphere is proportional to the radius cubed, so when the radius doubles, the volume becomes 2 cubed, or 8 times, larger.
Since average density = mass/volume, when the mass is multiplied by 2 and the volume is multiplied by 8, the average density is multiplied by 2/8 or 1/4.
So, when the mass is doubled, the average density becomes one quarter of what it was before.
(There is a rough analogy between a black hole and an atom. In both cases. the mass is concentrated in a tiny region at the centre, but the overall volume of each object is much bigger. Where the analogy breaks down is that the mass concentration at the centre of a black hole (the singularity) is infinitely large, which is not true of the atomic nucleus.)
Perhaps the universe is more like a black hole turned inside out, since it may have started as a singularity out of which material flowed.Assuming continuous expansion of the universe and negligible addition of mass then the universe was denser than a black hole a few billion years ago???
The universe was born to expand, which overcame the tendency for matter to collapse as it does in a black hole.
The Universe does not understand what humans want. Who Does?
Air, food, water, reproductive chores.
Humans like to talk the big talk. We make it all up. Our minds cannot perceive anything except AFWRC. The noises we make are of no consequence. We have wars to prove we are of no consequence.
Quite pretending you have something besides war and other petty events.
Impossible. Sorry, Charlie.
Air, food, water, reproductive chores.
Humans like to talk the big talk. We make it all up. Our minds cannot perceive anything except AFWRC. The noises we make are of no consequence. We have wars to prove we are of no consequence.
Quite pretending you have something besides war and other petty events.
Impossible. Sorry, Charlie.
Hmm. Bit of a rant.
Just a correction from me.
One puzzling feature is that the entropy of a black hole scales with its area rather than with its volume, since entropy is normally an extensive quantity that scales linearly with the volume of the system.
Black hole - Wikipedia
The area of a Black Hole is not directly proportional to the mass. I misunderstood. It grows as the square of the mass if I've got it right.
Just a correction from me.
One puzzling feature is that the entropy of a black hole scales with its area rather than with its volume, since entropy is normally an extensive quantity that scales linearly with the volume of the system.
Black hole - Wikipedia
The area of a Black Hole is not directly proportional to the mass. I misunderstood. It grows as the square of the mass if I've got it right.
I can be a bit of a glass half empty kind of guy myself.Hmm. Bit of a rant.
By always expecting the worst, I am seldom disappointed!
If time was being pushed forward by the entropy of the universe, we would see it as distance increasing and that may be an explanation for dark energy.
For dark matter, I find it intriguing that although the Milky Way is half the size of Andromeda and has half as many stars, it up to 2x Andromeda’s mass by some new estimates. Interestingly, Andromeda is estimated to be between 7 and 9 BY old - so at one extreme, a but more than half as old as the Milky Way.
For dark matter, I find it intriguing that although the Milky Way is half the size of Andromeda and has half as many stars, it up to 2x Andromeda’s mass by some new estimates. Interestingly, Andromeda is estimated to be between 7 and 9 BY old - so at one extreme, a but more than half as old as the Milky Way.
I think you probably meant the Milky Way Black Hole is about 4M Solar masses, Galu:
Sagittarius A* - Wikipedia
All a bit vague which galaxy is older.
Andromeda Galaxy - Wikipedia
Indra1 raises the problem with the universe being a Black Hole, since its mass ought to be increasing as it expands to work out right. Dark energy being created as it expands? But you can estimate that the escape velocity currently ought to be c.
Thing I never get is how the remnant of the big bang is all around us, rather than in one place.
Sagittarius A* - Wikipedia
All a bit vague which galaxy is older.
Andromeda Galaxy - Wikipedia
Indra1 raises the problem with the universe being a Black Hole, since its mass ought to be increasing as it expands to work out right. Dark energy being created as it expands? But you can estimate that the escape velocity currently ought to be c.
Thing I never get is how the remnant of the big bang is all around us, rather than in one place.
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Question : What does Hawking radiation looks like viewed from inside of the event horizon?
Answer : CMB
Viewed from the Outerverse where formation of the singularity that becomes our Universe took place, the remnant of our big bang is all lumped into a point at a certain coordinate, surrounded by an event horizon.
Yes. 4.1 million - a mere slip of the keyboard.
But, hey, what's a million solar masses among friends!
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