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Manoj Nikhil
Worked at Corporate World
Attended IIMC,New Delhi
Lives in New Delhi
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Manoj Nikhil

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Pointed Debate

Yesterday’s post on black holes stirred up things a bit, particularly among those who truly think black holes don’t exist. Some of the counter-arguments centered on the strangeness of event horizons, but most of it centered on the fact that black holes have singularities, which clearly defy all things science. Ergo, black holes don’t exist. Here we go again.

To begin with, let’s talk a little bit about what a singularity is and what it has to do with black holes. In simple terms, as the weight of an object tries to cause it to collapse, the pressure of the material pushes back until an equilibrium is reached. In the case of a star, it is the pressure of heated plasma that balances the weight, while for a white dwarf or neutron star it is the quantum degeneracy pressure of electrons or neutrons respectively. But at ever higher densities, the weight becomes harder to overcome. What’s worse, since mass and energy are related in relativity, there comes a point where the pressure of a material actually increases the weight, so the very thing used to counter gravity becomes part of the problem. It’s kind of like putting a fire out with water. Pour water on a small fire and it quickly goes out. Pour water on the Sun, and the weight of the water actually increases the Sun’s mass, which causes the Sun to heat up.

So the basic idea is that for things more dense than a neutron star, you get to the point where things are too dense to reach equilibrium. Even trying to create enough pressure to counter gravity would only help gravity, and so collapse is inevitable. The material of a star would simple collapse until there is literally no smaller volume to occupy. It would become a point of infinite density and zero volume, which is known as a singularity. At this point some of you are probably thinking “see, this is the kind of model-dependent nonsense I’m talking about.” Clearly singularities are nonsense, so clearly black holes don’t exist.

Interestingly, this is exactly the type of argument many astrophysicists made when black holes were first proposed. Even Einstein doubted black holes were possible. So you’re in good company if you doubt black holes, but you’re also about a century behind the times. Despite the way black holes are often presented, it wasn’t the model that convinced astrophysicists of black holes, it was the evidence.

The first “black hole” solution to Einstein’s general relativity equations was found by Karl Schwarzschild in 1916. At the time Schwarzschild himself showed that strange nonsensical things happened in the solution, which we now call the event horizon and the singularity. Interestingly, it was the event horizon that was seen as more problematic, because the “singularity” was just a mathematical concept, just like treating objects as point masses in Newtonian gravity. But soon more sophisticated models showed that matter within the event horizon of a black hole would most certainly collapse into a singularity. So for decades it was thought that black holes simply wouldn’t form. Surely the dynamics of material would prevent anything that dense from actually happening.

But in the 1960s neutron stars were discovered. It became clear that you could have several solar masses compressed into the volume the size of a small city. Neutron stars are fairly close to the critical density of a black hole, so it wasn’t unreasonable to imagine a collision or accretion of mass from another star triggering the formation a black hole. By the 1970s and 1980s there was growing evidence of black holes, both from x-ray binaries and the like for stellar mass black holes, and quasars and galaxy jets for supermassive black holes. In our own galaxy we now have orbital evidence from stars that show a supermassive black hole in our own galaxy. It is now decidedly clear that black holes exist.

But what about that pesky singularity? That’s actually a matter of some debate. Some argue that Hawking radiation will prevent singularities from forming. Some argue that things like dark energy might prevent their formation. Others argue that “singularities” might actually be a mechanism for forming other universes. It’s all pretty speculative, and they should all be considered a bit speculative.

But none of that disputes the existence of black holes. They are just discussions about one strange aspect of black holes. Models are a good way to understand things, but it’s the evidence that wins the day.
There is still much debate about black hole singularities, even though it's pretty clear black holes exist.
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PAINTOGRAPHY OF THE LANDSCAPE

Taken just before sunset the Taygetos Mountains near Sparta on the Manni Peninsula of Southern Greece bask in the evening light. Shot with my Sony a77 at f16 and ISO-200 for a 1/250th second exposure. Lens is my 18-250mm set at 75mm

More Photos and Helpful Tutorials on my website.  http://www.trueportraits.com/

#landscapephotography +Landscape Photography +Landscape Photography Show +Margaret Tompkins +Jim Warthman +Kevin Rowe +Johan Peijnenburg +David Heath Williams +Tom Hierl +Carolyn Lim +Howard L. Smith +Kai Kosonen +Sheila B. DuBois +Toshi Nakamura +David Pilasky +Bill Wood +Tony Phillips +Jeff Beddow

#themagicoflight Curators +Ray Bilcliff +Hamid Dastmalchi +Paul Stein

#paintography +Paintography Curator is +Ray Bilcliff   
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Panorama I took last night at Jenkins Lake in northern California. Looking west
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The Great Orion Nebula (M42)

I finally got around to processing my M42 that I captured the other night. This is my first time processing with a new software which had a steep learning curve but the results are well worth it. This is an LRGB image processed with PixInsight. Thanks for viewing and feel free to share. If you would like to see more night skies, wildlife and landscapes from Ontario, Canada feel free to add me to your circles.

Exif: 
Canon 7D mk ii
EF 500mm f/4
f/4 - ISO 3200
30x120 seconds
20x15 seconds
+ dark frames
Skywatcher HEQ5 Pro 
processed with PI, PS and Lr

Please do not download, copy or manipulate this image or any of my images without the written permission of Wesley Liikane. Thanks

©2015 - Wesley Liikane - Cowboy with a Camera
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The Entire Milky Way Might Be a Huge Wormhole That’s Stable and Navigable

Our very own Milky Way could be home to a giant tunnel in spacetime.

At least, that’s what the authors of a new study have proposed. According to the team, a collaboration between Indian, Italian, and North American researchers at the International School for Advanced Studies (SISSA) in Italy, the central halo of our galaxy may harbor enough dark matter to support the creation and sustenance of a “stable and navigable” shortcut to a distant region of spacetime – a phenomenon known as a wormhole.

Want to know more? Visit: http://www.universetoday.com/118423/the-entire-milky-way-might-be-a-huge-wormhole-thats-stable-and-navigable/
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In his circles
66 people
Have him in circles
64 people
Satya Singh's profile photo
chandan shahi's profile photo
Krishna Patel's profile photo
Dibyalochan Nayak's profile photo
Arnav Upadhyay's profile photo
sriram gupta's profile photo
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Education
  • IIMC,New Delhi
    AD & PR, 2004 - 2005
    Post Graduate Diploma in Advertising & Public Relation
  • FMS, New Delhi,
    Marketing & Sales, 2011 - 2014
    MBA-Marketing & Sales
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Painting, Sketching, Art & Spiritual Thoughts
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Marketing Professional
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Strategic Planning (Media & Marketing), Business Development, Brand Development, Consumer Insight & Marketing Management
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Superpower Vs. Soul
www.sidhagyangunj.com

Superpower is present everywhere in this Universe, every soul is floating just like bubble in this Universe and Nature is present as a barri

Veer Vetaal
www.sidhagyangunj.com

Vetaal is the symbol of power, courage and manhood so it is called Veer Vetaal. It is related to Itar Yoni and placed in highest level in te