Another late night thinking (brainfart) game - Page 1
Forum section: electronics / general

author: Vtile
author_rank: Super Contributor
timestamp: December 26, 2017, 12:28:16 am
content: So we have a black hole. Black hole sucks all the matter around them to one point and the matter reach the speed of light near the center. The matter consist of charge Q and because the matter reach near indefinite density also the current will reach almost infinite magnitude and therefore creates infinitely big magnetic field around the path. What happens in point when the space is empty around the black hole as there is no moving charge anymore and the magnetic field collapses.Obviously time for some sleep.

author: DC1MC
author_rank: Super Contributor
timestamp: December 26, 2017, 12:33:11 am
content: OK, another one, from the military, why is water always ENTERING in a perforated boot and EXITING a perforated can, why can't decide to have a consistent behavior ?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 26, 2017, 09:30:08 am
content: There is such a thing as a charged black hole. The internal structure is different from a neutral, non-spinning (Swartzchild) black hole!You seem to have omitted that most matter is charge neutral, so that no net current or charge accumulates.If a black hole were fed a stream of charge, the electric field* would build up, and eventually repel the stream, even if the stream is fired at the black hole at great velocity.*But ah, you say: surely nothing can escape a black hole, not even electric field? True; but because, as viewed from the outside, matter falls ever more slowly towards the event horizon without ever crossing it, theentire history of the black holeis written on its surface. It should be no surprise that current theoretically known black hole properties (like entropy) are proportional not to mass... but to surface area!Tim

author: jonovid
author_rank: Super Contributor
timestamp: December 26, 2017, 10:09:16 am
content: how can one know what is in a black hole when there is nothing

author: kalel
author_rank: Frequent Contributor
timestamp: December 26, 2017, 01:34:32 pm
content: Quote from: jonovid on December 26, 2017, 10:09:16 amI don't know any knowledge about black holes, but if it sucks matter in, then there is the sucked in matter? That should be something. Plus, if the black hole is a strong gravitational field, then there is at least something, that field itself.For me, absolute nothing is a difficult concept to imagine. What is outside of the expanding universe? Is it nothing?

author: Damianos
author_rank: Frequent Contributor
timestamp: December 26, 2017, 04:36:10 pm
content: Quote from: Vtile on December 26, 2017, 12:28:16 amFrom my little knowledge, in our conventional world, the charge Q that you mention is equalized (positive is equal to negative), so the referred current is near zero. The magnetic field, which created by an almost zero current, is virtually zero. What happens when a zero magnetic field collapses?Unless you intend to carry a load of charged material there ... ...PS: By rereading the posts, it seems that I am attempting to translate what T3sl4co1l stated in a ... simpler language!

author: Vtile
author_rank: Super Contributor
timestamp: December 26, 2017, 05:41:36 pm
content: Quote from: Damianos on December 26, 2017, 04:36:10 pmYep. That I were thinking also, hence the brainfart part on the tittle. To be honest these finesses of the physics have escaped from my head..Happy holidays to everyone.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 27, 2017, 12:47:37 am
content: Quote from: kalel on December 26, 2017, 01:34:32 pmOn the very smallest of scales, the vacuum is not at all empty, but teeming with a "foam" of virtual particles: the quantum vacuum.On the very largest, it's filled with matter. As far as we can tell, the universe is larger than twice the observable size (i.e., ~90G ly), and probably bigger.Indeed, the reason Big Bang Cosmology is present theory, is because it just so happens to be a configuration of matter and space which exhibits flat curvature and an ever-expanding scale. It's the perfect fit for what we see in our little neighborhood.That is to say, if you set up a universe with a uniform mass density -- the same everywhere, throughout all of infinite space -- the spacetime will naturally expand along the time direction. Since uniform expansion means more and more velocity at greater and greater distances, there necessarily will be regions that are travelling away from a given point at greater than the speed of light (proper time). Thus, any given point has a horizon, beyond which the rest of the universe cannot be seen; and this fits our observations today.Tim