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Comment: Re:Decentralization, do you speak it? (Score 1) 111

by mcelrath (#48517809) Attached to: MasterCard Rails Against Bitcoin's (Semi-)Anonymity

Coffee shop employees are perfectly capable of skimming credit cards so they can perform illicit transactions also. I've had that happen to me too. The technical ability to so easily skim numbers is what enables fraud. There's no encryption there.

"I never authorized that charge" was not sufficient for my bank. So then it's off to court...

Comment: Re:Decentralization, do you speak it? (Score 1) 111

by mcelrath (#48517653) Attached to: MasterCard Rails Against Bitcoin's (Semi-)Anonymity

Because the courts are the best way to reverse transactions. I've had the scenario you describe regarding road tolls and car rentals, and I challenged it with my bank. Got me exactly nowhere. I suppose I could go to court for a $75 fine, but who has time for that?

Legally some jurisdictions may consider it a one-time charge, but technically they have everything they need to perform a second charge, and it's your blood sweat and tears to challenge the fraud. That waiter skimming cards will not be deterred by your long, expensive, legal-system charge reversal plan.

Comment: Re:Decentralization, do you speak it? (Score 2) 111

by mcelrath (#48515239) Attached to: MasterCard Rails Against Bitcoin's (Semi-)Anonymity

The non-anonymity of MC transactions is a huge liability. Not only does my MC payment for my coffee allow me to pay for my coffee, but it also allows the merchant to perform future transactions (whether valid or not). It's an authorization not a one-time transaction. This price is just too high and is the source of all CC fraud. There is no reason why any merchant needs to know who I am. If customers choose to disclose their identity to sign up for their email spam, that's their problem, but I should not have to pony up my identity to perform most consumer transactions. The only reason merchants check ID's on transactions is as a flawed fraud protection measure. It protects them, but at my expense.

Anonymous transactions are be better.

Comment: Re: s/Identify/Hypothesize/ (Score 1) 103

by mcelrath (#48287137) Attached to: Physicists Identify Possible New Particle Behind Dark Matter

Him theory is not considered credible by anyone I've ever talked to (I am a theoretical physicist). I can't really say more, I haven't studied it.

And we all hope a method to compute at strong coupling will arise. And if one does, one could computer the bound state spectrum of the dark matter sector, and do the calculation the authors suggest correctly. Maybe their suggestion is even correct, but their calculation is wrong without consideration of bound states.

Comment: s/Identify/Hypothesize/ (Score 4, Insightful) 103

by mcelrath (#48282951) Attached to: Physicists Identify Possible New Particle Behind Dark Matter

No one has "identified" anything. This is a paper with a proposal, an idea, a hypothesis. Behind it lie a rather gigantic pile of assumptions and parameters to fit the data. It's long been speculated that Dark Matter may not be simple, but rather could be as complicated as the visible spectrum (which contains electrons, photons, atoms, and the entire periodic table). But there's a huge problem with making predictions in a strongly interacting theory: you generally can't. "Strong interactions" mean that most computations do not converge. For instance we cannot, from first principles, calculate the mass of any atomic nuclei.

So this means the "dark matter sector" contains essentially a whole periodic table of stuff, and we're hopelessly unable to compute anything. This paper in particular ignores the possibility of bound states (e.g. atoms, mesons, etc) in the dark matter sector, which IMHO is just silly especially with strong interactions.

Comment: Re:It's always dark matter. Except when it isn't. (Score 1) 100

by mcelrath (#47319585) Attached to: Mysterious X-ray Signal Hints At Dark Matter

Wikipedia is usually a good reference. These two articles talk about it. It's the oldest evidence for "dark matter". Either that or it's evidence that gravity doesn't behave entirely the way described by Einstein. The latter view has fallen out of favor due to the lack of good theories adopting that viewpoint. The former has fallen into favor due to the copious selection of theories containing a particle with little or no interactions (it's easy to do). Neither of these theory-spaces has been proven to be correct (yet).

Comment: It's always dark matter. Except when it isn't. (Score 0) 100

by mcelrath (#47318579) Attached to: Mysterious X-ray Signal Hints At Dark Matter

Hey look, it's $something_we_dont_understand, and ooh, I can claim it's evidence for $todays_fad!

Astrophysics is big, messy, complicated, and difficult to measure. We just can't send probes to other galaxies to see what's really going on. Most of the time these things have more mundane explanations. But, until we figure out why galactic rotation curves are wonky, everyone will claim everything is due to dark matter.

Comment: Re:No point encrypting if you're the only one... (Score 2) 108

I've been using GPG for more than a decade, but in recent years I've stopped signing my messages because it often trips up poorly-configured spam filters. That, combined with the fact that you can't be certain that the recipient has received or read a message makes using GPG (and potentially losing your email) risky.

While "read receipts" exist in many proprietary formats, we need it to be standardized and deployed globally. Hey, let's use our GPG keys to do it?

Comment: Bitcoin as a government experiment (Score 1) 221

by mcelrath (#46467661) Attached to: The Future of Cryptocurrencies

I've always wondered whether Bitcoin actually originated with the CIA, NSA, or Federal Reserve (or analogous agencies in other countries), or maybe a major bank.

I mean, it's a brilliant kind of experiment. Let it loose in the wild and see how it behaves, as a prelude to adopting an official, government backed version, using the lessons learned from Bitcoin. It's the kind of thing you want to have in the wild, to see what people do with it, before adopting something in an ad-hoc and flawed way (like credit cards..).

Comment: BTRFS or ZFS (Score 1) 321

by mcelrath (#45652345) Attached to: Ask Slashdot: Practical Bitrot Detection For Backups?

BTRFS and ZFS both do checksumming and can detect bit-rot. If you create a RAID array with them (using their native RAID capabilities) they can automatically correct it too. Using rsync and unison I once found a file with a nice track of modified bytes in it -- spinning rust makes a great cosmic ray or nuclear recoil detector. Or maybe the cosmic ray hit the RAM and it got written to disk. So, use ECC RAM.

But "bit-rot" occurs far less frequently than this: I find is that on a semi-regular basis my entire filesystem gets trashed (about once every year or three). This happened to me just last RAID1 BTRFS partitions (both of them) got trashed because one of my memory modules went bad. In the past I've had power supplies go bad causing this, or brown outs, and in other cases I never identified the cause. I've seen this happen across ext3, jfs, xfs, and btrfs so it's (probably) not the file system's fault. In such cases, fsck will often make the problem worse. (Use LVM and its "snapshot" feature to perform fsck on a snapshot without destroying the original). You'd think these advanced filesystems would have a way to rewind to a working copy (for instance in BTRFS -- mount a previous "generation") but this seems to not be the case.

Anyway, btrfs guys, your recovery tools could be a lot better. The COW enables some pretty fancy recovery techniques that you guys don't seem to be doing yet. If you've got a great btrfs or zfs recovery technique, please reply and tell us.

Comment: Re:City of Vienna, anyone ? (Score 1, Informative) 234

by mcelrath (#45575203) Attached to: Property Managers Use DNA To Sniff Out Dog Poop Offenders
Brilliant. Every time I've been forced to not pick up poop, it was because I didn't have a bag, not because I wanted to (and where possible I always go back and get it later). I've had my dog shit three times on one walk. I'm really tired of hearing "solutions" to problems created by psychopaths. This "solution" using poop and DNA utterly lacks empathy towards dog owners, and that's what psychopaths do. There are better ways.

fortune: cannot execute. Out of cookies.