Forget Lamb. This is what we are all going to be eating in the future:
Low-Greenhouse gas, you see. As an early adopter, I am on it already.
The Energy dashboard was fascinating:
Energy Dashboard - real time and historical UK energy figures, analysis and mapping
Windmills going a storm right now! Very impressive. Over a quarter of our power. I just checked and it is very windy in the UK right now:
Ventusky - Wind, Rain and Temperature Maps
Solar Panels are hopeless at this time of year. I know this because my neighbour's garden solar lights were totally feeble last night, after a grey rainy day. You can see how much we need a mixture of Energy sources depending on the weather. Don't know how useful Tidal power might be. That's pretty regular.
I have the abstract from Albert Snepppen here:
I didn't find the maths easy at all, but I am guessing he is saying that the gravitational lensing at each edge will depend on whether that edge is spinning towards you or away from you. TBH, it seems unlikely to me that Black Holes will be spinning at any appreciable velocity at all, certainly not 99% of the speed of light, but I could be wrong.
Low-Greenhouse gas, you see. As an early adopter, I am on it already.
The Energy dashboard was fascinating:
Energy Dashboard - real time and historical UK energy figures, analysis and mapping
Windmills going a storm right now! Very impressive. Over a quarter of our power. I just checked and it is very windy in the UK right now:
Ventusky - Wind, Rain and Temperature Maps
Solar Panels are hopeless at this time of year. I know this because my neighbour's garden solar lights were totally feeble last night, after a grey rainy day. You can see how much we need a mixture of Energy sources depending on the weather. Don't know how useful Tidal power might be. That's pretty regular.
I have the abstract from Albert Snepppen here:
Albert Snepppen (sic) said:
I didn't find the maths easy at all, but I am guessing he is saying that the gravitational lensing at each edge will depend on whether that edge is spinning towards you or away from you. TBH, it seems unlikely to me that Black Holes will be spinning at any appreciable velocity at all, certainly not 99% of the speed of light, but I could be wrong.
This Is Why Black Holes Must Spin At Almost The Speed Of Light
It’s usually very high. Even Neutron stars angular velocity regularly approaches relativistic speeds at their equators.
It’s usually very high. Even Neutron stars angular velocity regularly approaches relativistic speeds at their equators.
Nice article on new series from Prof Brian Cox
Earth’s demise could rid galaxy of meaning, warns Brian Cox ahead of Cop26 | Brian Cox | The Guardian
He went on: “The more I learn about biology … the more astonished I am we exist at all”, adding that while astronomers said there were about 20bn Earth-like planets in the Milky Way galaxy, “so we might expect life to be everywhere”, “almost every biologist I speak to says, ‘Yes, but all it will be is slime at best.’ We live in a violent universe and the idea you can have planets which are stable enough to have an unbroken chain of life might be quite restrictive.”
Earth’s demise could rid galaxy of meaning, warns Brian Cox ahead of Cop26 | Brian Cox | The Guardian
He went on: “The more I learn about biology … the more astonished I am we exist at all”, adding that while astronomers said there were about 20bn Earth-like planets in the Milky Way galaxy, “so we might expect life to be everywhere”, “almost every biologist I speak to says, ‘Yes, but all it will be is slime at best.’ We live in a violent universe and the idea you can have planets which are stable enough to have an unbroken chain of life might be quite restrictive.”
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The supermassive black hole 'sweeps clean' the volume at the heart of the galaxy, consuming those stars which were in range of its gravitational influence.
When it has consumed all the nearby material it goes into a 'dormant' stage, just like the one at the heart of our galaxy.
The rest of the galaxy survives, as you can confirm by looking up into the night sky to view our own Milky Way galaxy.
However, supermassive black holes can be 'woken up' by intergalactic collisions, during which fresh material comes within their sphere of influence.
You mean that the linear velocity (v) at the equator can approach the speed of light.
v = r ω (where r = the radius of the star and ω is its angular velocity).
I've seen one example of the linear velocity of a neutron star at its equator - 70,000 km per second or approximately 24% of the speed of light.
Nice bit of publicity!
The new series 'Universe', presented by Prof Brian Cox, starts on BBC2 on 27 October.
I'm looking forward to it! BBC Two - Universe
Bonsai and Galu, we shall forget Prof. Brian Cox for now. Everything is "AMAZING" to that man. Not that I mind some enthusiasm. You are wandering off on a tangent again.
We need to resolve this spinning Black Hole business before anything else. You started it!
I accept that Black Holes might be spinning very fast, but it seems there are processes which can leak away that spin:
Penrose process - Wikipedia
Albert Sneppen is calculating the effect on light or particles of spinning Black Holes. It is called the Kerr-Metric:
Kerr metric - Wikipedia
Some other visualisations here:
Rotating black hole - Wikipedia
In fact the last link looks like the Black Hole in the Interstellar movie. Interesting.
We need to resolve this spinning Black Hole business before anything else. You started it!
I accept that Black Holes might be spinning very fast, but it seems there are processes which can leak away that spin:
Penrose process - Wikipedia
Albert Sneppen is calculating the effect on light or particles of spinning Black Holes. It is called the Kerr-Metric:
Kerr metric - Wikipedia
Some other visualisations here:
Rotating black hole - Wikipedia
In fact the last link looks like the Black Hole in the Interstellar movie. Interesting.
We couldn't possibly have avoided discussing the topic earlier in the thread, could we?
As explained in the Wikipedia link, there are four 'metrics' which relate to black holes, depending on their rotation and charge.
The names of these four metrics are oulined in bold in the following summary:
- A Schwarzschild black hole, or ‘static black hole’, does not rotate and has no electric charge. It is characterised solely by its mass.
- A Kerr black hole is a more realistic scenario. This is a rotating black hole with no electrical charge.
- A charged black hole can be of two types. A charged, non-rotating black hole is known as a Reissner-Nordstrom black hole and a charged, rotating black hole is called a Kerr-Newman black hole.
I found this suggested as a possible process:
"A black hole can change its spin either by accreting mass and the associated angular momentum, or by giving angular momentum to matter in its close vicinity."
This is significant because we can't actually see a black hole spin!
However the fact that light is bent differently depending on how it passes by a black hole is a major proof that the black hole is spinning.
As Galu has explained, there are 4 classes of BH. We only know of spinning BHs’ ie. no static BH have been detected in practice. And as Ethan Siegel explains BH’s must spin at appreciable % of the speed of light.
Rotating black hole - Wikipedia
Secondly, Prof Cox does seem to find everything amazing. But then so do I.
Rotating black hole - Wikipedia
Secondly, Prof Cox does seem to find everything amazing. But then so do I.
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A Schwarzschild non-rotating black hole probably doesn’t exist.
The charged rotating and non-rotating black holes are theoretical.
So, when we are talking about a rotating black hole, we are talking about the Kerr version.
The Kerr black hole produces the spacetime distortion that bends Sneppen's light.
The charged rotating and non-rotating black holes are theoretical.
So, when we are talking about a rotating black hole, we are talking about the Kerr version.
The Kerr black hole produces the spacetime distortion that bends Sneppen's light.
You mean like eating too much and vomiting.
"No more nuuts".
Stick to your frozen compartmentalized microwavedinners. 😀
I'de like to know more, I do not see how spinning can do something to the light bending; So far in my understanding, only comes in, the mass.However the fact that light is bent differently depending on how it passes by a black hole is a major proof that the black hole is spinning.
I was thinking of '"frame-dragging" when the fabric of space itself gets dragged round by the spinning black hole so that light traveling in the direction of rotation of the black hole will move past it faster than light moving against the rotation.
However, you are correct and the deflection of the light is explained by the curvature of space due to the mass of the black hole - as explained in the link given earlier: Danish student solves decades long mystery regarding light and black holes
However, you are correct and the deflection of the light is explained by the curvature of space due to the mass of the black hole - as explained in the link given earlier: Danish student solves decades long mystery regarding light and black holes
I'll blame Steve's misinterpretation for setting me off on a wild goose chase!
I find your comment highly distatsteful.
Mind you only from what I hear as I have no experience with such. Your comment, post #7339 seemed analogous to another Seinfeld episode where uncle Leo lay on the bed having eaten too many macadamia nuts that time when the crew was exploiting the amenities at a high end hotel at Jerry's expense, unbeknownst to him. My quote is Leo's lament.
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