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Airbus Attacked By French Lawmaker For Talking To SpaceX

EdgePenguin Re:This is not news (166 comments)

All of this is true. I am not attacking actual SpaceX, I'm attacking the libertarian fantasy version of SpaceX where a genius entrepreneur forges a rocket purely with the power of his mind and all the government does is hold him back. This is not an argument of "Well you suck too!" its just a statement that no launch service is entirely independent of government nor likely will be any time soon. I agree that SpaceX seems to be operating a lot better than some of the more well established US launch providers - but is that an indication that SpaceX is really groundbreaking, or that the old guard were simply complacent and greedy?

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re:Dark matter and the sniff test (83 comments)

Because the equations aren't "off" at all. They precisely predict the mass density of the universe and the baryon density of the universe from observations. The difference between these two values is very well established. Read the results papers from Planck and WMAP.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re: Dark matter and the sniff test (83 comments)

Thats right. Spheroidal systems in astrophysics are generally held up against gravity by such random motions, whereas flattened systems tend towards being help up by ordered rotation.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re:I'm also an engineer (83 comments)

Yes, we are all Educated Stupid and thats why we don't believe in Timecube!

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re: Dark matter and the sniff test (83 comments)

Another good question. Gas can lose energy because it interacts with other radiation and matter, but dark matter cannot. The total angular momentum of the system must always be conserved, and a disk is the lowest energy configuration that does this. Both dark matter and gas start off in the spheroidal arrangement, and then the gas the cools to form a disk.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re: Dark matter and the sniff test (83 comments)

The claims are "extreme" because you don't like them, and the confidence of astrophysicists in this matter is a consequence of the overwhelming weight of evidence.

You have decided to take a position on a subject you are completely ignorant of, and that contrary positions to this are "extreme" and thus must be treated as fringe nuttery. Essentially, you think that your ad hoc guesses should be treated like the null hypothesis. You can try and dress it up in as much intellectual sounding language as you like, but you are being absolutely moronic and I'm done with you.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re: Dark matter and the sniff test (83 comments)

Stop. Really. You are embarrassing yourself. That is EXACTLY what you meant. You said I thought "the equations were off in two regards", so clearly you didn't know about any of the other evidence of dark matter. Now you are back-pedalling as you slowly realise you are not even vaguely qualified to be in this conversation.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re: Dark matter and the sniff test (83 comments)

I never said there was no other evidence for dark matter. The ratio of deuterium and the acoustic peaks of the CMB require most of the mass in the universe to be non baryonic. I simply stated the evidence that this non baryonic matter makes up most of the MW-M31 system. Your strident arrogance, coupled with your immense ignorance of the subject matter, would make a wiser person stay quiet.

5 days ago
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Airbus Attacked By French Lawmaker For Talking To SpaceX

EdgePenguin This is not news (166 comments)

All governments prop up their launch industries. Yes, this includes the US government supporting SpaceX: they wouldn't have made it through their early difficulties without NASA support. Elon Musk readily acknowledges this, its more his libertarian fanboys wanting to hold up as some paragon of the all-conquering private sector.

That said, Ariane 5 is now looking a bit subsidy heavy, despite it being a very commercially successful launcher for years. This is why they are trying to make Ariane 6 much cheaper. If this doesn't work, or rather can't be made to work without an unacceptable subsidy, ESA really needs to look towards Skylon.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re:Dark matter and the sniff test (83 comments)

Although you make the common error of thinking that the only requirement for dark matter is galaxy/cluster dynamics, you have stumbled on an interesting question; why is the Milky Way dynamically dominated by dark matter but the solar system is not. Fortunately, its easily answered.

Dark matter makes up most of the mass of galaxies, including the Milky Way. One of the best bits of evidence our own galaxy has dark matter is the rate at which M31 (Andromeda) is approaching us. The expansion of the universe drives galaxies apart, so the combined mass of the local group (basically just us and M31, M33 is next in mass but its much smaller than M31) has to be enough to pull the two galaxies together such that you would see M31 at the present distance and velocity. This is called the local group timing argument, and it shows that there is much more mass than can be accounted for with visible matter in the local group. This is not the only evidence for dark matter, but it along with the milk way rotation curve makes us confident that there is substantial dark mass in our galaxy.

As to the reason you don't see much dark matter impacting on the gravity of the solar system: that comes down to geometry. dark matter is arranged in a spheroidal halo whereas most of the visible matter is in a thin disk. The dark matter halo is much less dense in our galaxy than visible matter (and especially so in our solar system as for obvious reasons its got a higher density than the galaxy as a whole) but for large enough $r$, proportionality to $r^3$ always wins out over proportionality to $r^2$, which is why dark matter dominates the outer part of the rotation curve whilst at the same time being irrelevant for the internal kinematics of our solar system.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Dark Matter is not a tweak to gravity (83 comments)

A lot of engineers and computer programmers seem to think that dark matter is just a fudge to make rotation curves fit, and that they being smarter than astrophysicists can see through this obvious error. This is profoundly irritating

Dark matter is required to explain the ratio of elements produced during big bang nucleosynthesis, the acoustic peaks of the cosmic microwave background, gravitational lensing, cluster dynamics, the Local Group timing and finally, yes, rotation curves. In the last application (which is bizarrely considered to be the only place dark matter is invoked), the most popular alternative hypothesis MOND, which has no theoretical basis and exists purely to fit rotation curve data, doesn't actually do that well on modern rotation curves.

You cannot offering any critical comment on dark matter that won't make you sound like a terminal case of Dunning-Kruger to an astrophysicist unless you understand all of the things I mentioned above.

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re:I'm also an engineer (83 comments)

You do not have a better theory. You have a hypothesis, posted on a webpage. This is timecube territory, sorry. Why is it that engineers make such laughably bad attempts to second guess scientists? And why do they insist on bothering actual scientists with mass emails about their crazy ideas?

5 days ago
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Deflating Claims That ESA Craft Has Spotted Dark Matter

EdgePenguin Re:Dark matter and the sniff test (83 comments)

Dark matter is NOT a kludge factor. You should not make such strident pronouncements about a subject you clearly know nothing about. The existence of dark matter is not controversial amongst astrophysicists.

The fraction of deuterium produced by primordial nucleosynthesis, and the ratio between the acoustic peaks in the CMB, both require ~83% of the mass of the universe to be something other than baryons. Given that these two indicators are from entirely separate epochs (about a hundred seconds after the big bang for the former, and hundreds of thousands of years for the latter) this is a strong result.

5 days ago
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Startup Out of MIT Promises Digital Afterlife — Just Hand Over Your Data

EdgePenguin Creepy interactive gravestone (241 comments)

This is not transferring your mind into a machine. Its not even vaguely a step in that direction. Why would this be any kind of 'afterlife'?

about a year ago
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AMC Theaters Allegedly Calls FBI to Interrogate a Google Glass Wearer

EdgePenguin Re: A collision of stupid (1034 comments)

He chose to put his prescription lenses in the thing, and apparently doesn't have a spare set. He chose to be a permanent camera wearer. He doesn't get to hide behind a disability defence.

about a year ago
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AMC Theaters Allegedly Calls FBI to Interrogate a Google Glass Wearer

EdgePenguin A collision of stupid (1034 comments)

Assuming the story is true...

1. The cinema guy is stupid for calling the FBI and escalating the situation way out of hand.

2. The MPAA/FBI are stupid for actually putting time and resources into fighting cam-rips. Absolutely no threat to the industry, as anybody who has tried to watch one knows. Letting pirates have their cam-rips just makes authentic cinemagoing look better.

3. The Glasshole was stupid for sitting in a cinema quite openly pointing a camera at the screen. Glass users appear to have their empathy surgically removed by Google, and are entirely oblivious to any kind of reaction anybody might have to a ubiquitous filming device. Repeating "but it isn't on" as a mantra does nothing to help. Having a face camera redefines your relations with other people and your environment, in an almost entirely negative way. You want to become a surveillance drone? Fine, deal with the social consequences.

I'm normally on the side of the little guy, and against big media throwing its weight around. Glassholes are sufficiently selfish and idiotic for me to momentarily switch sides. I've already written about what a crappy society such people would create: http://edgepenguin.com/content...

about a year ago
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AMC Theaters Allegedly Calls FBI to Interrogate a Google Glass Wearer

EdgePenguin Re:Two words ... (1034 comments)

Consider yourselves lucky to be American then. In the UK, the courts are allowed to infer guilt from your silence.

about a year ago
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Billion Star Surveyor 'Gaia' Lifts Off

EdgePenguin Re:Total map size (77 comments)

I meant to say some of the data is discarded. The paper I read discussed reconstructing a galaxy images to take into account the information Gaia throws away before downloading it to the ground station.

about a year ago
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Billion Star Surveyor 'Gaia' Lifts Off

EdgePenguin Re:Total map size (77 comments)

It will find galaxies, sort of. Gaia doesn't really care what it is looking at, it simply tags every point of light in its field that is bright enough. Things that aren't stars are then to be discarded when the data is processed. There was a recent paper published suggesting that some of these discarded galaxies could be surveyed in order to get even more science value out of Gaia.

about a year ago

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