question about "dumb holes"

[Stephen]

My questions were asked after reading Chelle's comments on the subject. Put it together with the fact that CERN bothered mentioning this subject in their safety report, and you have a legitimate reason to be slightly concerned. Yes, I'm aware of the meaning of the things I'm talking about. I already realized these concerns have no basis in reality, but the natural reaction when hearing about such phenomenons is to worry a bit.

[curiouser1]

Thanks again for further explanation, although I admit any explanation is plausible when one's physics knowledge is limited to some undergraduate classes.

So, I'll ask a better question if y'all aren't tired of them yet... do the findings at Haifa University have absolutely any bearing upon the behavior of microscopic black holes?

http://en.wikipedia.org/wiki/Dumb_hole

This makes it sound like they might. Possibly wiki entry needs editing if this is not the case?

And one more point... we are relative teenagers (if you will) in the process of understanding particle physics. This is why I both respect what is happening at CERN and feel cautious about it as well. A large fundamental misunderstanding at *my* job may result in injury to a person, even a loss of a life. A large fundamental misunderstanding of our universe's properties may result in paying an even dearer price at some point.

[chelle]

And one more point... we are relative teenagers (if you will) in the process of understanding particle physics. This is why I both respect what is happening at CERN and feel cautious about it as well. A large fundamental misunderstanding at *my* job may result in injury to a person, even a loss of a life. A large fundamental misunderstanding of our universe's properties may result in paying an even dearer price at some point.

You know "curiouser1" this experiment is just like the one of the frog in boiling water (wiki). Everyone who's "new" to this says; "Ouch!! the lhc is a pretty hot experiment", but the people used to these experiments do no longer realise that there are significant dangers, and say; "Relax it's all good, look we are doing this long time and where still here".

btw if you never seen the kermit in the kitchen story take a look at this:
http://www.youtube.com/watch?v=svpsLZDgFK4
Note: there has been no harm done in that experiment because we already know how it will end. And indeed we are all teens, but some of us think that they are wise enough to lead us into a direction where non of us has ever been. So I personally would suggest we better turn the heat a bit down, before we're getting our asses burned off.

[mrgumby]

If we want to learn new things, we must go places we have not been before. This should be fairly obvious.

If we do not want to learn new things we will stagnate. This too is fairly obvious.

If you have a fear of new knowledge you should seek help rather than try to scare others.
This also is blindingly obvious.

[chelle]

A recent update on "Dumb Holes" (January 10, 2011):

Physicists create sonic black hole in the lab

link: http://www.physorg.com/news/2011-01-phy ... e-lab.html

The researchers created the sonic black hole in a Bose-Einstein condensate made of 100,000 rubidium atoms slowed to their lowest quantum state in a magnetic trap. This cold cluster of atoms acts like a single, large quantum mechanical object. In order to transform this condensate into a sonic black hole, the scientists had to find a way to accelerate some of the condensate to supersonic speeds so that the condensate would contain some regions of supersonic flow and some regions of subsonic flow.
...

[chelle]

If we want to learn new things, we must go places we have not been before. This should be fairly obvious.

If we do not want to learn new things we will stagnate. This too is fairly obvious.

If you have a fear of new knowledge you should seek help rather than try to scare others.
This also is blindingly obvious.

I know I'm being an ass ... but in the light of the disaster in Fukushima ... I would like to point out how easily people forget that things can go wrong, when things have been going good for a long time, and as you can see skeptics are even given the advice to 'see help'. Bringing this back to the LHC and other nuclear experiments, pushing boundaries further and further into the unknown is not without a certain risk, and the 'new' isn't always what you ask for.

[Kasuha]

I know I'm being an ass ... but in the light of the disaster in Fukushima ...

In the light of the disaster in Japan, I would like to point out how easily people lose their reference frame and fail to see that what happened (or rather what could but did not happen) in Fukushima is in reality a proof of how extremely reliable nuclear plants are.

[chelle]

I know I'm being an ass ... but in the light of the disaster in Fukushima ...

In the light of the disaster in Japan, I would like to point out how easily people lose their reference frame and fail to see that what happened (or rather what could but did not happen) in Fukushima is in reality a proof of how extremely reliable nuclear plants are.

Ok so the uncontrollable tiger only bit off the head of the tamer who went into the cage, but hey it shows us how strong the cage is! Who's going the tame the pink elephant that we are hunting for with the lhc?

[draph91]

well according to Luis Sancho on Cerntruth (it's a load of BS)

"Further on, in Haifa a few years ago, an homologous of a black hole, a Dumb Hole made of atomic condensates, 1 million time slower, that should have evaporated producing phonons instead of photons, didn’t. It proved once more than Hawking is wrong and Einstein is right"

He's wrong by the way

I asked about this on 2012hoax and 3WMElliott and TheGreatJuju had this to say

"The experiment at Haifa actually occurred. They were not, however, even looking for Hawking radiation. I'm not sure they're even certain yet how to detect it"

There was an experiment, making a black hole for sound instead of light. From what little I've read (there is a paper on arXiv for those interested) it was not that there was no radiation (which is what this guy is saying) but that there was no way to observe whether there was any radiation (quite a different claim, no?).

also i found this as well

Wave-Generated ‘White Hole’ Boosts Hawking Radiation Theory: UBC Research

January 17, 2011

A team of UBC physicists and engineers have designed an experiment featuring a trough of flowing water to help bolster a 35-year-old theory proposed by eminent physicist Stephen Hawking.

In 1974, Hawking predicted that black holes--often thought of having gravitational pulls so strong that nothing escapes from them--emit a very weak level of radiation. According to the theory, pairs of photons are torn apart by a black hole's gravitational field--one photon falls into the black hole, but the other escapes as a form of radiation.

In results outlined in the latest issue of Physical Review Letters, a team of UBC researchers led by international postdoctoral researcher Silke Weinfurtner put the test to Hawking's theory by creating a 'white hole' in a six-metre-long flume of flowing water.

Placing an airplane wing-shaped obstacle in the path of the flowing water created a region of high-velocity flow which blocked surface waves, generated downstream, from traveling upstream. The obstruction simulated a white hole, the temporal reverse of a black hole.

The shallow surface waves divided into pairs of deep-water waves, analogous to the photon pairs featured in Hawking's theory. Like in black holes, they showed that the analog would also emit a thermal spectrum of radiation.

"While this creative simulation obviously doesn’t prove Hawking's theory, it does show that his ideas apply broadly," says UBC theoretical physicist William Unruh, part of the team which included European Union Marie Curie Fellow Weinfurtner, undergraduate student Matthew Penrice, Civil Engineering post doctoral fellow Edmund Tedford, and Canada Research Chair in Environmental Fluid Mechanics Gregory Lawrence.

"In addition to their relevance to Hawking's theory, the experiments have raised a number of unanswered fluid mechanics questions of engineering interest," says Lawrence.

"This experiment also exemplifies all of the strengths of UBC's research enterprise--the involvement of students, our international outreach and connections, and a very open, collaborative way of looking at scientific questions," says Unruh.