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Comment Re:duh (Score 1) 182

Though if they want to maximize readability, why aren't the using fonts with the little training wheels specially designed to make letters faster to read and easier to recognize in bad reading conditions, what's the name: SERIF fonts!

For road signs, they don't want to maximize readability, they want to maximize legibility, which is not the same thing. For example see: It's About Legibility:

While the argument continues to rage about whether sans serifs are easier to read than serif fonts in text copy, sans serif typefaces, because their letter shapes are simpler, have been proven to be slightly more legible than their serifed cousins.

I agree that serif fonts are generally more readable than sans-serif fonts. Having to read a book that is entirely sans-serif is a chore. The serifed fonts are usually easier to read because the serifs help guide your eye to scan an entire line of text. But for road signs, it is more important to recognize words than to scan lines. That's why they use sans-serif fonts which have been found to be more legible. For signs, you don't need serifs to guide your eye like when you are reading a page of text. In addition, the serifs act like noise and make it slightly more difficult to recognize single letters, especially when parts of the letters are obscured.

Comment Re:Guns actually protect people (Score 3, Insightful) 190

I started reading the "study" you base your entire argument on and it seemed to be a suspicious jumble of cherry-picked facts, and thus more of a political polemic with an axe to grind than an objective scientific study so I did a search to find out more about the authors and discovered that either you were purposely misleading people here or you were misled yourself.

For example, Snopes highlights many of the flaws with the non-peer reviewed paper you cite as a "study":

Claim: A 2007 Harvard University study proved that areas with higher rates of gun ownership have lower crime rates.


WHAT'S TRUE: Gun rights advocates Gary Mauser and Don Kates jointly authored a 2007 paper in the Harvard Journal of Law & Public Policy arguing that higher rates of gun ownership correlated with lower crime rates.

WHAT'S FALSE: The paper in question was not peer-reviewed, it didn't constitute a study, and it misrepresented separate research to draw shaky, unsupported conclusions.

[...] Of primary importance is the subsequent, widely misapplied label of the word "study" with reference to the 2007 item in question. The Harvard Journal of Law & Public Policy describes itself as "one of the most widely circulated student-edited law reviews and the nation's leading forum for conservative and libertarian legal scholarship." Papers published in that journal are (while perhaps competitively sourced) in no way equivalent to peer-reviewed research published in a credible science-related journals as "studies." Use of the term "study" to refer that 2007 article dishonestly suggested that the assertions made by its authors were gathered and vetted under more rigorous study conditions, which didn't appear to be the case.

[...] In short, the purported 2007 Harvard "study" with "astonishing" findings was in fact a polemic paper penned by two well-known gun rights activists. Its findings were neither peer-reviewed nor subject to academic scrutiny of any sort prior to its appearance, and the publication that carried it was a self-identified ideology-based editorial outlet edited by Harvard students.

Comment Re:Issues? How about major security holes? (Score 1) 349

And if you have physical access to a booting machine, its owner may already be f#cked.

Using that logic, nobody should ever be required to type a password when physically present at the console.

Using that logic then we should never implement security features that deter passersby but will not stop a determined attacker.

Comment Re:Only if you Exclude Technological Limits (Score 4, Interesting) 288

What if their goal isn't to make a testable prediction that diverges from the current best theory, but merely to explain more elegantly what's already explained? Shouldn't that count as scientific progress too?

An excellent question! Yes, more elegant explanations of existing phenomena are definitely a big part of science. The unification of electricity and magnetism is an example . But that unification led to new predictions that the non-unified models did not. Yet, even if string theory was able to make the same predictions as the standard model and no new predictions then, hell yeah, it is would be science. The problem is that it makes no predictions. Well, to be more accurate, it makes way too many predictions which is pretty much the same thing.

You see, explaining what has already been explained involves making testable predictions. String theory does not do this which is why it is not science. That doesn't mean it is worthless to pursue.

Comment Re:The dark matter between their ears (Score 1) 171

gravity is as instantaneous as people can detect - ie its not at the speed of light.

That is not actually known. We still haven't figured out if gravity propagates at the speed of light or not.

In 1916 Einstein figured out that gravity propagates at the speed of light. We just haven't measured it directly yet.

Comment Re:Do you want to pay for advertising? (Score 1) 305

You could say that about any product. You could argue that McDonald's shouldn't be allowed to advertise because it increases the price of a Big Mac. Why not just ban advertising in general?

We don't need to ban it but we sure as hell should stop subsidizing it. Advertising should not be treated as a business expense that can be deducted from taxes, it should be taxed heavily the same way that pollution should be taxed heavily because they are both negative externalities. The rationalization that advertising helps consumers by making them better informed is total bullshit. We all have limited time on earth and limited attention. If someone wants to use my limited time and attention then they should pay me for that. I shouldn't be paying them for it.

Comment Re:Can you liberals please wake the fuck up? (Score 1) 965

So your solution to terrorism is mass genocide? The decision for us to commit much greater atrocities is not "in the hands of the clerics and other muslim [sic] leaders around the world". They are not responsible for our actions, we are. Nor are they responsible for the actions of the people who committed this horrible attack. In addition, why would you expect the attackers to treat us as fellow humans when you are not willing to treat them that way?

We started this bloody awful mess and they see themselves as fighting back and defending themselves in the only way the can. The most effective way to get someone to act subhuman is to treat them as subhuman. Repaying atrocity with atrocity might give you some emotional relief but it is about as effective as pouring gasoline on a fire or copulating for virginity.

I pray we do not become the evil we abhor. As long as enough people choose to dehumanize their fellow human beings then there will be no end to the escalating violence on both sides.

Comment Re:Can you liberals please wake the fuck up? (Score 1) 965


People who would do such things are animals and aren't worth dealing with on an even level. If they wish to behave this way, then they should be treated that way.

Albert Einstein:

We cannot solve our problems with the same thinking we used when we created them.

IOW, your reaction to dehumanize the people who did this plays right into their hands. ISIS was created by and survives on atrocities committed by the West. I'm not saying this justifies the attack. I'm saying that from a pragmatic perspective dehumanizing the attackers is extremely stupid and short-sighted.

Comment Re:Scientists (Score 2) 203

> I have not seen any reasonable theoretical explanation for the anomalous force that is purported to power the EM drive
The only thing that critics have managed to say about emdrive theory over 10 years is " muh momentum "

What else can we reply when there is no actually theory presented that we can reply to or refute? All we have to go on is some micro-wave engineer claims that he has invented a device that violates conservation of momentum without providing any reasonable theory for how it might work. Your attempt to blame the critics for the complete lack of theoretical underpinnings by the inventor is ridiculous. The inventor himself said:

I am just a microwave engineer and all that matters is that it works.

In addition, the Anonymous Coward engineer claims:

Emdrive has been experimentally verified by 5 institutions with results published.

(emphasis added)

Have experimental results been published? Yes. Has the effect been verified? No. Most of the extraordinary experimental results seem to have been either debunked or retracted, claims such as nearly one Newton of thrust by a paper from China which has been shrouded in mystery. The more recent and reliable Tajimar paper explicitly says:

... we successfully identified experimental areas needing additional attention before any firm conclusions concerning the EMDrive claims could be made. Out test campaign therefore can neither confirm or refute the claims of the EMDrive [...]

In one of their experiments their measured thrust was in the wrong direction! Their conclusion that the experiments need to be improved before they can be used to verify the EMDrive claims echoes what I already said (and you mocked) that the current experimental results are buried down with the noise. That is what the fine post linked to by the summary says as well. The experimentalists are working on beating back known sources of noise so they will eventually be in a position to confirm or refute the EMDrive claims. It is not all relevant if totally different experiments with totally different devices had better signal to noise ratios with similar input powers and output thrusts.

Your mocking, your ad hominem attacks, and your appeals to emotion and irrelevancies do nothing to bolster your argument. Your claims far exceed the claims of the very experimentalists whose work you (appear to) cite. You are, of course, free to believe whatever the heck you want but it seems your claims of experimental verification are greatly overblown. For me, the lack of theoretical underpinnings, the violation of the conservation of momentum, and the lack of experimental verification (as I cited above and from the fine post linked to in summary) all make me highly dubious that the effect is real.

Comment Re:Scientists (Score 1) 203

Because his prior work, from which the EMDrive stems, is a laser-gyroscope functioning on the exact same principles as the EMDrive in reverse [...]

This is complete hogwash. The effects cannot be related because the laser-gyroscope is based fundamentally on rotational velocities being absolute. Linear velocities (even without Einstein's relativity) are relative. OTOH, it makes some sense that an engineer who developed their intuition based on laser-gyroscopes would misapply that intuition to "invent" the EMDrive.

Shawyer's theory states the greatest way to improve thrust from existing models would be to make a perfect-Q cavity [...]

Can you point to an actual theoretical explanation/prediction of the effect? Shawyer himself said:

I am just a microwave engineer and all that matters is that it works.

This was in reference to his claim (in 2007) of creating a EMDrive that produced 0.1 Newtons (100,000 microNewtons, 1000 times larger than the effect measured in the post from the summary). Was that claim debunked or abandoned? If not, then why are we farting around with machines that only produce 100 micro-Newtons?

In 2012 there was a claim from China about producing an EMDrive that created nearly 1 Newton of thrust. Many people were dubious of this claim because the test wasn't performed in a vacuum so the thrust could have been created by thermal effects (like a Crookes radiometer). Now we are talking about better experiments where the effect has been reduced by a factor of 10,000 and is down in the noise level while the experimenters are working on decreasing the sources of noise. Everything about Shawyer's claim reeks of crockpottery. Sure, if something like this actually existed then it could be the gateway to interstellar travel. But that only makes these dubious claims more suspicious.

Comment Re:Scientists (Score 3, Informative) 203

The problem is not the absolute smallness of 100 micro-Newtons. The problem is the relative size of 100-micro-Newtons compared to the forces that exist in the experimental apparatus. It is like confusing absolute signal level with the signal to noise ratio. Yes, we can easily measure the weight of a snowflake. But if the total thrust from this 100 watt drive is equivalent to the weight of a snowflake then I am exceedingly unimpressed. If you read the fine post that is linked to, you will see that this is literally down in the level of noise that can be produced by ground loops and so on. The author is basically saying that they tried to remove even more noise sources than last time and still have not yet tracked down what is causing the extremely tiny anomalous thrust they have measured.

I am a physicist so I am well aware of just how bloody difficult it is to track down and account for every form of noise and error in experiments like this one. Or in the experiment that measured neutrinos traveling faster than the speed of light. I am often cautioning my friends to not get too excited about weak experimental results like this that contradict foundational physical theories. I also cautioned people to not get too excited about the so-called "face on Mars" for the same reasons. Lots of fascinating things are seen in weak signals that are close to the experimental noise floor.

In addition, I have not seen any reasonable theoretical explanation for the anomalous force that is purported to power the EM drive. There is certainly no relationship between the purported physics of an EM drive and the actual physics of a ring laser gyroscope. Nor have I seen any reasonable theoretical explanation for why the thrust should scale as a large power of the input energy. Yet many people here who ignore the experimental challenges of measuring the weight of a snowflake on top of the forces acting on an apparatus dissipating 100 watts of RF energy seem to blithely accept these remarkable and, AFAIK unfounded, theoretical claims as gospel truth.

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