[Red Badger]

I guess the PC crowd has moved into astronomy.......

[period end of story]

Half white, half black?

[Abathar]

I did that experiment too when I pulled the plug on my bathwater. Think I could get a grant to tell them what color the water was at the event horizon with the soap bubbles being sucked down?

[norton]

"Normal waves heave up and down in the direction they move, whereas anti-waves do the opposite."

That certainly clarifies things.

[WayneS]

Now, if we could only get the water to flow at a speed approaching that of light, we’d REALLY be in business.

How does this demonstrate that “black holes are not black after all.”?

[EagleandLiberty]

Jessie Jackson & Al Sharpton will PROTEST this finding!!

[KarlInOhio]

This is hardly an analog to a black hole. In fact it looks like a well known phenomenon from pipes transmitting sounds (like musical instruments). If you transmit a sound down its length and the end is open, an inverse of the original wave will be transmitted back up the pipe. Similar things happen with an improperly terminated electrical cable.

It's and interesting physics demonstration, but they are extrapolating from a common physical example to try to understand one of the strangest items in the universe.

[coloradan]

It’s hard to imagine how a very classical, Newtonian world of water waves could have anything to do with the very quantum, relativistic world in the vicinity of a black hole’s event horizon. To point out one glaring difference, the speed of sound in water is about 1 km/sec, much faster than the flow.

[BibChr]

Mauve Holes?

[exile]

Al (Not so)Sharpton is going to be p!ssed.

[Eye On The Left]

Gravitational fields are mainly about "escape velocity". EV is the speed required for something to escape the grip of the mass creating the gravitational field. On Earth the EV is about 18,000 miles/hr. With a mass just great enough to form a black hole, the EV is light speed (186,000 miles per second). The surrounding distance from the center of the BH where EV is light speed is called the Event Horizon. The size of the EH (its radius) depends on the amount of mass inside the black hole. There are small black holes with masses several times that of our sun and there are enormous ones (at the heart of many if not most galaxies) with masses billions of times that of the sun. In the case of these galactic black holes, the EH is thought to be as large as our solar system or greater (~8 billion miles in diameter). The reason BH are 'black' is that the gravitational field is so great that not even light can escape it.

[Hegemony Cricket]

Holes of color, thank you very much...

[SunkenCiv]

[LibWhacker]

Space seems to flow, and the closer one gets to the black hole, the faster it flows.

That's a very strange idea... The idea of space itself flowing down a black hole faster than the speed of light. I've run into it before here (PDF file) but more or less interpreted it as just an analogy, a mathematically equivalently way to look at the problem.

But if space actually is flowing like water, that is just so bizarre.... And with billions, or even trillions, of black holes out there in the universe sucking space down faster than the speed of light, in effect destroying it, or removing it from the universe, it's mind-boggling that there is yet some other mechanism out there (called dark energy) that totally dominates the whole space equation thing, adding space, expanding the universe, much, much faster than all those trillions of black holes can gobble it up and destroy it.

[Telepathic Intruder]

I’m really compelled to say that space doesn’t “flow” into a black hole. Gravity is a space-time curvature. I don’t like ridiculous concepts.

[Captain Beyond]

bump

[CougarGA7]

What are we suppossed to call them now?

Holes of Color?