What is the Universe expanding into..

Do you think there was anything before the big bang?

  • I don't think there was anything before the Big Bang

    Votes: 56 12.5%
  • I think something existed before the Big Bang

    Votes: 200 44.7%
  • I don't think the big bang happened

    Votes: 54 12.1%
  • I think the universe is part of a mutiverse

    Votes: 201 45.0%

  • Total voters
    447
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If I was out on a limb I'd say he's correct.
angif-go-out-on-a-limb-def.jpg
 

TNT

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So now that you're in research mood, can I bend your ear/eye to answer this question if it's answerable: Hypothetically, if a person falls into a black hole, would they have a sensation of falling forever as in like a bottomless pit? That is if they could live forever.

First of all it's not a hole despite the unfortunate name. It a solid body in the shape of a sphere and it has a very high density. Very....... high. How would i know its "round" as a ball i.e. a sphere. Well, any body of considerable mass, like earth or the moon, could not sustain to maintain any other shape due to gravity. Here you also have the reason why flat-eartheners are wrong.

So when you fall down on a supermassive body (what you referred to as a black hole), you are sliced, shredded and grind to pieces before you hit ground.

You are welcome ;)

//
 
A black hole is a tremendous amount of matter crammed into a very small (in fact, zero) amount of space - called a singularity.

When we talk about 'entering' a black hole, we mean crossing its event horizon Event horizon - Wikipedia after which we would fall towards the singularity.

No one knows what happens when you enter the singularity. The laws of physics, as we know them, don't apply there. Perhaps you would be crunched down not just to cells or even atoms, but to a perfect sea of energy - but that's just conjecture.
 
A list of known magnetars is given in Bonsai's Wikipedia link.

As of November 2020, there are 29 known magnetars in our Milky Way galaxy.

Magnetars were thought to be responsible for Fast Radio Bursts (FRBs) and this was confirmed in April 2020 when multiple radio telescopes detected an FRB from a magnetar near the center of the Milky Way.

The dozens of other FRBs detected before that had all come from far outside our galaxy, making it impossible to track their source.
 
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A list of known magnetars is given in Bonsai's Wikipedia link.

As of November 2020, there are 29 known magnetars in our Milky Way galaxy.

Magnetars were thought to be responsible for Fast Radio Bursts (FRBs) and this was confirmed in April 2020 when multiple radio telescopes detected an FRB from a magnetar near the center of the Milky Way.

The dozens of other FRBs detected before that had all come from far outside our galaxy, making it impossible to track their source.
Oh thanks. It slipped my notice
 
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The mag field strengths are so strong that atoms are squeezed into long thin shapes so anything within a thousand miles gets ripped to shreds. The mag field is still well below the Schwinger limit (10^18 T which is when free space is no longer magnetically linear anymore)

The other interesting objects are quasars.

BTW just finishing off reading Stephen Weinberg’s ‘The First Three Minutes’. Written in the mid 1970’s it’s a bit outdated, but there’s a prologue at the back that pulls much of it into the mid 1990’s. (Useful math addendum at the back of the book as well)
 
The other interesting objects are quasars.
Quasars are among the brightest objects in the universe - luminous, active galactic nuclei powered by supermassive black holes that are actively feeding on nearby material.

Recently, scientists have found the most distant quasar yet known, residing about 13 billion light-years from Earth. They estimate that this particular quasar's seriously supermassive black hole ingests an amount of mass equivalent to 25 Suns every year.

The first quasar ever to be identified is 3C 273, which is one of the closest quasars to us at a mere 2.5 billion light-years away. It was discovered in the 1960s.
 

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The energy is emitted by the material near the supermassive black hole which forms a hot accretion disc revolving at speeds of hundreds of thousands of miles per hour as the material spirals in towards the black hole and heats up to temperatures of millions of degrees.
 
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We have a supermassive black hole at the centre of our Milky Way galaxy, but currently it is quiescent.

However, there is evidence to suggest that it may have been an active quasar just a few million years ago.

This evidence is in the form of two giant bubbles that extend 25,000 light-years above and below the galactic center and are emitting gamma rays.
 

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