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by Watsisname
16 Oct 2017 20:31
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy News
Replies: 348
Views: 15243

Science and Astronomy News

It is an incredibly big moment for gravitational wave astronomy.  We have detected several black hole mergers already, but now for the first time we have a gravitational wave event observed coincident with electromagnetic emission.  Black hole mergers are violent events, but the violence is almost p...
by Watsisname
15 Oct 2017 23:07
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy News
Replies: 348
Views: 15243

Science and Astronomy News

Indeed.  The motivation for proposing epicycles was to explain variable and retrograde apparent motion of the planets in a way that preserves the notion that things move around the Earth in heavenly circles.  What predictive power did epicycles have which help justify the proposition?   I don't know...
by Watsisname
15 Oct 2017 20:45
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy Questions
Replies: 702
Views: 30247

Science and Astronomy Questions

14681 Yes, I love math too!  Which is why I was so puzzled by it being called "gross."  I mean raw sewage is gross (or sewage of any kind)- but math?!  No! ;) https://i.imgur.com/yCX7Z5e.jpg 14681 How long will it be before we understand the details of the collapse and rotating black hole...
by Watsisname
15 Oct 2017 14:36
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy News
Replies: 348
Views: 15243

Science and Astronomy News

14774 Does anyone really categorically deny that dark energy can be described as an ad hoc hypothesis?   Even if we agree that it's ad hoc because there is still much we don't understand, that doesn't mean that it's wrong.  The question is rather whether we should shut the other doo...
by Watsisname
15 Oct 2017 07:01
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy News
Replies: 348
Views: 15243

Science and Astronomy News

Such critique of dark matter and dark energy as being ad hoc or unfalsifiable is quite common.  It  is also based on significant misconceptions. Dark energy is a name we give to the observed  accelerating expansion of the universe (measured from supernovae data).  When the cause of this acceleratio...
by Watsisname
13 Oct 2017 21:15
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy Videos
Replies: 271
Views: 13134

Science and Astronomy Videos

If the numbers loop back to negative, then you haven't gone high enough. :)  To illustrate with y=tan(x), that means you stepped too far in x, and thus missed a bunch of y.  In fact you did not just miss a bunch, but an infinite amount of it. :P  Get closer and closer to that singularity, and you m...
by Watsisname
13 Oct 2017 16:32
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy Videos
Replies: 271
Views: 13134

Science and Astronomy Videos

Yet multiplying zero by infinity does not yield 1.
by Watsisname
12 Oct 2017 19:16
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy Questions
Replies: 702
Views: 30247

Science and Astronomy Questions

Mr. Missed Her , I'm afraid this may be disappointing, but simply using the equation for an ellipse will not help you determine the position as a function of time for an orbit, because the speed is not constant but rather must obey the vis viva equation .  In fact, there is no algebraic expression ...
by Watsisname
12 Oct 2017 17:30
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy News
Replies: 348
Views: 15243

Science and Astronomy News

14661 Since we're talking about dark energy, I've got to ask: What if we're just in a less dense region of space bigger than the observable universe? The more dense universe around our patch would be pulling everything away from our observable region, and it looks like the universe is expanding. 14...
by Watsisname
12 Oct 2017 15:37
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy Questions
Replies: 702
Views: 30247

Science and Astronomy Questions

They're very neat as mathematical entities, but that's all they are.  Ring singularities do not exist in nature, but are simply consequences of assuming the mass of a rotating black hole exists at a point to begin with.  That assumption leads to predictions that contradicts itself, and the true natu...
by Watsisname
12 Oct 2017 00:46
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy News
Replies: 348
Views: 15243

Science and Astronomy News

14644 Would a plethora of tiny, moon-massed black holes effect our view of other galaxies? Perhaps surprisingly, no! To give an idea, the average mass density of dark matter in the universe equates to about 1.4 protons per cubic meter.  If it is all in the form of black holes with the mass of the M...
by Watsisname
10 Oct 2017 18:43
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy News
Replies: 348
Views: 15243

Science and Astronomy News

14595 Perhaps this missing matter is baryonic? https://arxiv.org/abs/1709.10378v1 There is a common misconception about these studies.   The researchers were not looking for a component of dark matter.  They were looking for a component of normal baryonic matter -- specifically warm gas in the fila...
by Watsisname
09 Oct 2017 23:31
Forum: Space Journeys
Topic: Image Dump
Replies: 1146
Views: 67145

Image Dump

Aborygen, your shot of the rings with the dark clouds in front may be one of my favorite screenshots of the last 5 years.  Awesome work, mate.
by Watsisname
09 Oct 2017 17:35
Forum: Science and Astronomy Discussions
Topic: Science and Astronomy Questions
Replies: 702
Views: 30247

Science and Astronomy Questions

If you think that's gross, the equation describing a rotating black hole is like a summoning spell for Cthulhu. :P   But anyway yes, you're thinking about it correctly. :)  If you fall into a black hole inside a box, physics in your box behaves just like physics anywhere else (in zero gee), at least...
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