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Comment: Re: Dark matter doesn't exist. (Score 2) 116

by radtea (#49480883) Attached to: Hubble and the VLT Uncover Evidence For Self-Interacting Dark Matter

One only needs to define the photon as a thermodynamic reexpansion of spacetime that was compressed by nearby matter.

Unfortunately that is not a meaningful statement. I have no idea what a "thermodynamic reexpansion" is versus a "non-thermodynamic reexpansion", for example. Nor is it clear how this would be expressed mathematically as a generalization of Maxwell's equations. Nor does your paper do anything more than repeat this meaningless statement.

There may be something meaningful and interesting to say about the thermodynamics of electromagnetism and space-time, but until you give us a mathematical statement of the physical principles you are trying to enunciate it is going to be very difficult for anyone to understand what, if anything, you are talking about.

Comment: Re:How have we ruled out measurement or model erro (Score 1) 116

by radtea (#49480607) Attached to: Hubble and the VLT Uncover Evidence For Self-Interacting Dark Matter

I'm waiting for someone to explain why so many seem so sure that it actually is some form of exotic matter.

You'll forgive me for believing that that is a lie, because this has been explained many, many times. On the balance of probabilities, you are an irrational nutjob who is resistant to any actual explanation or evidence.

That said, I'll waste few minutes of my precious time pretending your question is sincere and you have a non-zero chance of changing your mind.

The reason why we focus on exotic matter is because observational evidence for a source of anomalous gravitational attraction is robust and diverse and alternative theories have either failed to account for it, or have failed other observational tests.

It isn't as if we have a single measurement on one system. We have detailed measurements of the rotation curves of many spiral galaxies. We have the motion of galaxies in clusters. We have the motion of clusters themselves. We have gravitational lensing studies--which probe the dark matter distribution in a completely different way from dynamical studies. We have cosmological simulations that can't explain galaxy formation without dark matter. We have structure in the cosmic microwave background that is evidence for dark matter, in that it can be explained easily with it, but only with great difficulty without, just as hearing a dog bark is evidence for a dog because a dog easily explains barking, while alternative explanations have much lower priors and so are less plausible. To deny this is to deny Bayes.

Did I have to dig deeply into some mysterious literature to find this? No. I had to look at Wikipedia:

Do you see why I think your question is dishonest?

So that makes "maybe the measurements are in error" much less plausible than "dark matter exists".

With regard to new physics, the problem is that the low-hanging fruit have been picked, and what remains has a hard time explaining all the diverse observational evidence. It is hard to find a theory that explains all the phenomena that are observed that is not "there is some kind of exotic matter out there". None-the-less, we are actively testing a few such theories. Again from Wikipedia:

So now your question has been answered. You need wait no more. You can either change your mind, and agree that dark matter is the most plausible explanation of the robust and diverse observations, or you can explain why you find some alternative hypothesis more plausible. But you can never again honestly ask, "Why don't people take observational error or alternative theories more seriously?"

Comment: Re:why must human ancestors be involved (Score 1) 88

by radtea (#49480461) Attached to: World's Oldest Stone Tools Discovered In Kenya

As far as we know, humans are the only organisms that kill for sport.

As others have pointed out, this is false. Multiple species kill for fun.

War is mate competition pursued by other means. The reasons why humans kill each other is because it is an evolved, adaptive, behaviour carried over into a world that we are desperately trying to engineer in such a way that killing is no longer necessary or functional. The problem is that it's still fun: it feels good because we are the descendents of individuals who were selected to be good at it, and part of being good at it was enjoying it, getting an immediate, internal, biochemical reward for behaviour that was also adaptive (that produced more offspring).

As such, sports and other forms of competition that allow us to activate that in-built reward system without actually killing people are really important to keeping human society reasonably peaceful.

Comment: Re:better idea (Score 1) 165

by radtea (#49454581) Attached to: UN To Debate Lethal Autonomous Weapons

the rest was still a garbage heap of warring tribes, mainly until the Renaissance.

The tipping point was around the Gregorian revolution in the late 11th century (1050-1150 or thereabouts.) That was the point when Eastern civilizations were starting to stagnate and Western Europe was starting to get its act together. So the Renaissance was less of a "tremendous leap forward" than the bursting in to flower of a plant that had been growing for several centuries.

With regard to concerns about autonomous weapons, the things that people are pointing out as dangers are features from the point of view of the kind of person who thinks that mass organized violence is a useful way to address human problems (because it always works so well?)

Deniability and muddied legal responsibility are just what killers are looking for. They'll claim with every software release that civilian deaths are decreasing, and that might even be true, but the important thing is it will give idiots the ability to kill without accountability.

How stupid is war? Hitler wanted to secure German food supplies by using war to create an agrarian empire in Eastern Europe. This resulted in the utter destruction of Germany. If instead he had used Germany's expertise in phosphate and nitrate chemistry to investigate fertilizers instead of high explosives, the Green Revolution would have come decades early and he'd be remembered as a great man. This is not an isolated example: war almost never produces the outcome it's instigators intend, to the extent that if your name is not Bismark you're better off not starting one. There are always cheaper, more reliable means of achieving any end.

Comment: Re:Strictly speaking... (Score 1) 417

Unfortunately the news report carefully leaves out any numbers from the new study. It notes that over the past 200 years the average pH of the oceans have increased from 8.25 to 8.14, but makes no mention of the size of the increase studied in the report, so there is no way to tell if the headline is sensationalist nonsense or not.

Given the quality of scientific journalism, however, my prior is pretty heavily biased toward sensationalist nonsense.

Comment: Re:Great, Let's Build IFR's (Score 1) 417

There are actually quite a number of environmentalists who have suggested that we should use nuclear power in order to get off of fossil fuels.

While there are a few, no leading environmental organization is pro-nuclear. Greenpeace in particular is adamantly opposed to nuclear, even though they treat the IPCC reports as Biblically certain when it supports their anti-capitalist political agenda, and the IPCC clearly states that nuclear is one way to address CO2 pollution (particularly from base-load coal, which is very hard to replace otherwise).

So let's not kid ourselves: the environmental left wants to treat CO2 pollution as a moral and social problem, and they react to any suggestion that we treat it as a technological problem in the same way conservative Christians react to the suggestion that we treat teen pregnancy as a technological problem, and fix it via education and easily-available contraception. For the environmental left, smashing global capitalism, not saving the planet is the goal, and they strongly oppose anything that will save the latter without destroying the former (see Naiomi Klein's "This Changes Everything" for a textbook example of this position, all laid out in black and white.)

Comment: Re:The fucking cat (Score 1) 172

We can't directly observe a particle being in an indeterminate state

And this central mystery is still with us: why can't we? Decoherence people sometimes claim to have the answer, but they don't: they can explain why we don't see interference, not why interference is the only way we can be aware that particles are in indeterminate (classical) states.

Reality is very strange.

Comment: Re:it could have been an accident (Score 1) 737

by radtea (#49347797) Attached to: Germanwings Plane Crash Was No Accident

there is an infinitesimally small chance that it was engaged by accident.

And since air disasters necessarily depend on extremely low-probability events, this is not an argument for the proposition "therefore this was most likely not the cause".

We know that whatever happened it had an outrageously low probability. This makes speculation in advance of data useless, because there are an almost unlimited number of highly improbable things that could have happened, and anyone who thinks they can imagine their way to the correct one is innumerate:

Comment: So what are they? (Score 1) 126

by radtea (#49325469) Attached to: Boeing Patents <em>Star Wars</em> Style Force Field Technology

From the tortured summary the only thing that's clear is that this technology is nothing like anything in Star Wars or Star Trek, but some illiterate in PR has decided that whatever they actually do is so boring, obscure or useless that the only way to drum up any attention for them is to describe them in terms of something completely unrelated.

Does anyone have any idea what they actually do and how they do it?

Comment: Not Even Wrong (Score 5, Informative) 109

by radtea (#49304337) Attached to: The Stolen Credit For What Makes Up the Sun

This is not even wrong. Payne had the idea first, Russell thought it was wrong, Russell later changed his mind and gave Payne credit: His work cites hers.

This is how science is supposed to work, although there is always a factor of fame involved in credit-giving, and women have in general not been as forceful in claiming or defending credit as men.

Furthermore, how many people claiming to be "outraged" by this were even aware of who had been given credit for figuring out the composition of the sun in the first place? Who amongst us is "shocked, shocked" that Russell--whom they had been giving credit to all these years, citing in papers, talking up at cocktail parties--didn't actually make the discovery that is commonly and incorrectly attributed to him?

Comment: Re:fathers (Score 1) 299

by radtea (#49304275) Attached to: Scientists: It's Time To Resolve the Ethics of Editing Human Genome

What's being debated is whether it's right to make experiments who's consequences a person who can't consent to them has to carry.

And this differs from having children the old fashioned way how?

That is the crux: every child born is a genetic experiment today. We hope that it doesn't end up with too many defects. We hope that it's born with eyes (I know someone who wasn't). We hope that it's born without any non-lethal developmental defects (I know a couple of people who have them, caught and fixed by surgery before they became fatal.) We hope they won't develop Type I diabetes (like several of my friends have)... and so on.

Every one of these things is a crap-shoot, and everyone who has kids today is performing an uncontrolled genetic experiment every time.

To claim that this process is necessarily going to be made worse by adding some human intelligence to the mix is problematic. The claim that there is no conceivable therapeutic benefit to engineering certain classes of genetic defect out of the germline is disingenuous, unless you think everyone everywhere for the rest of time is going to have good gene therapy available to them while growing up, which is insane.

To claim "we can't predict what the effects might be so we shouldn't do the research" is bizarre: if we don't do the research, admittedly mostly on animal models, how will we ever know what the effects are? Once we've done the research, we will have a high confidence in the effects, just as we do with any other therapeutic intervention. We all know that iatrogenic disease is a major cause of death and suffering, so wringing our hands about germline modification as if it was unique in that respect is at the very least strange and at worst deeply hypocritical.

All power gets used, and it's understandable that people should be concerned about how the power to edit the human germline will be used. The possibilities for abuse are considerable. If we are ever able to create Brave-New-World style designer slaves, happy in their subjugation, we probably will, for some value of "we".

But the debate should be about how to use this power wisely, not whether we should develop it at all. Someone will, and it's better that that happen out in the open than in some secret lab in $EVIL_NATION or funded by $EVIL_BILLIONAIRE.

Comment: Re:Novelty Effect (Score 3, Interesting) 59

by radtea (#49277371) Attached to: New Site Mocks Bad Artwork On Ebook Covers

Cover design is hard, and most people do judge books by the cover. These books have content that is likely reflected by their covers pretty well, so in that sense I'd say most of them are pretty good.

The one a few pages in about the guy who's annoyed is really quite good: blunt, angry, simple. Since that's what the book looks to be like, how can the cover be bad?

For my book ( one of my first readers was an artist, so I hired her to do the cover art. It captures a lot of things about the book, and it's beautiful on its own, so it's a win.

But I'm sure a purist would find a million things wrong with it, from the ambiguities of the image to my choice of font (not papyrus or comic sans, but any font can be mocked if you work at it hard enough) to the choice of colours (too blue, not enough contrast) to the overall look (too cluttered, too busy)... and so on.

Still, my hope was to keep it reasonably low on the mockability scale, and while it's fun to mock stuff, but I have a depressing feeling that many of these mocked books are selling a lot better than a lot of less-mockable stuff. So maybe I should replace my cover with unicorns and rainbows and leather-clad half-dressed bikers to see if that boosts sales...

Comment: Re:common with 19th century novels (Score 4, Insightful) 104

by radtea (#49237003) Attached to: Some of the Greatest Science Fiction Novels Are Fix-Ups

Others have pointed out that these were serials, not fixups, although some Victorian authors may have published fixups: the concept is ancient.

Two examples:

1) the Iliad is probably a fixup. The first bunch of books are heavily focused on Diomedes, who then more-or-less disappears completely from the story. There is some contention that the parts of books V and VI dealing with him were once a separate story.

2) going even further back, Gilgamesh is probably a fixup. There's a good deal of evidence that it was assembled from pre-existing stories of Gilgamesh and Enkidu (and also Utnapishtim, the Chaldean "Noah" who was lifted by the early Hebrews along with so much else).

3) and the Bible itself, which seems to have been written rather late in Jewish history, almost certainly assembled from pre-existing stand-alone tales, which explains the contradictions in the two stories of creation and so on.

Comment: Re:Python/C++ Combo (Score 2) 757

by radtea (#49228707) Attached to: Was Linus Torvalds Right About C++ Being So Wrong?

But for me it is not one language but a pairing that has caught my heart.

I'm in the same boat, with the same languages. Python for convenience, C++ for speed. I also use C for really low level embedded (PIC) stuff, but that's it.

This combination gives me the optimal mix of portability and power for the problem domains I'm interested in, and at this point I don't see any reason to leave C++ for anything else. The big trick is to adopt and strictly adhere to a set of reasonable coding standards that keeps you from doing all the stupid things the language lets you do.

C++ demands a higher level of discipline and maturity from developers than most languages because Linus is right: it is incredibly easy to abuse. A bad programmer will write bad code in any language, but C++ makes it really easy for bad programmers to express themselves, and that's a bad thing. That doesn't mean the language is bad, but it does mean it should only be used where its advantages (portability, efficiency, expressive power) are sufficiently great to overcome its weaknesses (excessive complexity, mediocre type safety, excessive complexity.)

Never say you know a man until you have divided an inheritance with him.