Black Holes, White Dwarfs, and other Dead Stars -Part 2

[clickben]

when two black holes merge it becomes black hole caniballizum the bigger one aparrently eats the other

[yambutter]

What happens when blackholes merge? How does it happen physically and mathematically (be kind it's been a long time since college)? Love your lecture.

[bignewgame]

You made a comment that the magnetic fields accelerate particles. Then you agree that particles are affected by magnetic fields. I have a theory that matter is created 90° of a magnetic field. That is why matter forms on a disk around stars. I can give you more detail if you like.

[jas2754]

Magnetic Fields accelerate charged particles such as electrons.. that comes out of standard Electromagnetic theory.

[bignewgame]

Is the gravitational field and magnetic field one and the same? If gravity is what is stopping particles then why do particles escape from black holes magnetic poles? Wouldn't gravity on a black holes be the same at the magnetic poles as it is at the equator?

[jas2754]

Magnetic Fields and Gravitational fields are quite different. Gravity is the attraction between masses. Magnetic fields are associated with electic charges and currents.

To your second question.. basically yes. Particles don't escape once they are in the event horizon of the BH

[HammerSickle]

nice and precise presentation, good for the beginners.

[jas2754]

Thank You for that comment... the presentations are aimed precisely for the beginners. I use as a supplement for some of my teaching at the intro level.

[rygaku]

you wouldnt fall into the black hole you are suspended in time in space but i though you would get ripped apart. you cant pass the event horizone beacuse you are areadly it?

[jas2754]

You are suspended in time and space from an observer outside the BH, but for the person falling it, it is not static at all. As you get near or pass the event horizon the gravitational tidal forces can be strong enough to tear you apart. The Tidal force depends on the size of the BH.. for a very large BH the tidal forces at the event horizon are relatively lower than for a small BH...sounds conterintuitive but that is the case.

[rottenvenetic]

You don't have to get anywhere near the event horison to be ripped to a spagetti by the black hole's gravity, especially if it's a supermassive one.

[jas2754]

Tidal forces are what rip you into a spagetti... as the BH increases in size(mass) the tidal forces get smaller at the event horizon! ..taking this to a limit there is a point where even a spagetti would not get ripped apart!

[rygaku]

i have a question a black hole the size of a cd can ita destroye the earth in minutes or hours.

[rygaku]

like jas2754 said even if te object of size inters it is ripped from molecue by molecue feeding the black hole. even if you some how orbit the black hole you wont escape time its self is slowly destroyed so is space.

[jas2754]

Gravity is not related to magnetic field. IN your argument "magnetic field attracts all other bodies" .. the answer is now. A magnetic fields can exert a force on a moving charged particle only... this makes a big difference.

[penguin10916]

What becomes of the objects that go through a black hole?

[jas2754]

Path 2- However inside a black hole these is mass and energy( light ..... so I would say in the situation you are mentioning, if somehow you had a working retina deep within the hole... you could be inundated with light... it would not be dark at all! Now the answer is more complicated by the fact that if there is nothing falling into the black hole at the time of observation... it would be dark

[Thepidgeonmaster]

I know next to nothing about astrophysics, as i am a microbiologist. But i was wondering if by some mircale you where stand deep within the hole without, being cruhsed. Would you be able to see anything. Because how i figure it is that the light will be pulled into the hole and so the light will never reach the back of the retina.

Please settle this drink fueled argument for me.

[jas2754]

LOL ! .. it is quite a hypothetical..and whatever the answer no one can verify this for sure just on information theoretic grounds.,,,you cannot get any information from anything within the event horizon .

[grubelsucht]

What size are black holes? Could their gravity pull in large celestial structures, like our solar system, for example?

[jas2754]

Good question and the answer is yes it can pull in large objects like other stars and planets. It is not a pretty process..the tidal forces in a small blackhole will tear things apart as they near the event horizon which represents the radius of no escape. THe radius of the event horizon depends linearly on mass. For a 10 solar mass black hole the radius is about 30 Km. ( the size of a small earth city!)

[IMBUED]

super black holes can move entire galaxies, quess whats in the center of each galaxy? :) some are active some arint, some say that black holes actual can lay dorment, start up, and stop for periods of time,