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Comment Re:No you can't (Score 1) 249

Well, no, because they are now just in B reference frame.

Yes. You defined B as the universal reference time.

One hour later still, C would see the sign and think A is wrong, as it is clearly not 4 p.m. plus 2 hours, in C's local time.

Except presumably C would be smart enough to know that A is not in C's local time and would be able to say to themselves "Yep, it was 4pm in A's local time when A said it was 4pm."

Remember, you wouldn't have a "simple" transformation like saying C = B+1 as we do with timezones on Earth. Your transformation would be more along the lines of "C = L*B" for some Lorentz transformation L (or whatever appropriate equivalent if we need to involve full on GR.) And in that case, "C = L*L*A" would be the appropriate double transformation, not "C = 2*L*A".

Comment Re:Nothing? (Score 1) 429

It's one thing to say "it's too hard to find both position and velocity"

You can go ahead and stop right there. Its not just "too hard," its mathematically impossible with our current understanding of quantum mechanics.

That literally is the Heisenberg uncertainty principle. Which is not just some off-the-cuff remark about our inability to try. Its an actual formal theory with mathematics to back it up. And as far as anyone's been able to determine experimentally, the mathematics bear out in the real world (though our experiments -- even the LHC -- are still orders of magnitude too weak to fully confirm the HUP at the smallest scales we assume it operates. And we don't even have any generally accepted theories for what might be going on below that scale yet.)

Comment Re:Nothing? (Score 1) 429

Your first one is easy to answer intuitively -- A and B are moving at nearly the speed of light not at the speed of light. Enormously different, mathematically speaking.

If B is moving toward P at say, 0.99c and A is moving away from P at 0.99c, B would see P "approaching" at 0.99c but it would say A approaching at say 0.995c (for example.. I can't be bothered working out the real number.. but it would be something 0.99c<v<1.0c -- that is, faster than P's approach but still less than c.)

As for the second, I'm not particularly sure that either SR or GR actually imply any means to rotate the universe needs to exist -- they just say that *IF* you rotate it, the laws of physics wouldn't change.

Consider a simple flat object on a turntable. Assume you can rotate it 90 degrees using X units of energy. If you rotate it clockwise by 90 degrees, you will have used X units of energy. If you rotate it 270 degrees counterclockwise, it will be in the same final state but you will have used 3X units of energy to get there.

Comment Re:But... (Score 1) 249

Where in the universe is it the "correct" time?

Wherever you decide it should be. The universe doesn't have any special reference frame so you just make one up. Similar to how somebody just arbitrarily picked a line of longitude to be GMT+0 back when they were figuring out time zones.

Comment Re: Old saying (Score 1, Insightful) 249

Yes but you can perform a transformation to translate from one reference frame to another, and while the universe may not give special meaning to any particular reference frame, there's nothing stopping us from doing so. So in theory you can define a "universal" time if you want.

Similar to choosing where to place the origin on a sheet of graph paper. It doesn't really matter where you put it (mathematically at least) but once its there you have a perfectly meaningful "universal" point of reference to use when describing the positions of other objects.

The trouble of course is computing the transformation parameters with enough accuracy to matter, which I'm assuming is implausible on our not-mathematically-perfect planet.

Comment Re:I just got a message from the future! (Score 1) 151

Hopefully prior to that, you would have gotten a weekly (if not daily) warning on your cell phone that your taillight is out. That would remove ignorance of the issue as an excuse, and it would help people like me who legitimately don't notice shit like that 90% of the time. The only time I'd notice a taillight out is if I was reversing in near-darkness for some reason.

Comment Re:left/right apocalypse (Score 1) 495

I don't know why not.. I mean there should be lots of geologic-timescale events in the past few decades to compare.

And that's ignoring the fact that while the earth has certainly been hotter in the past, the speed of increase over the past 100-150 years is, as far as we know, entirely unprecedented.

So yeah. Should be simple to find examples of similar occurrences.

Comment Re:oooh GMO is to oscary u guys! (Score 1) 432

Tell that to the more than 50,000 veterans who are still suffering from Agent Orange exposure.

Yeah I realized I should have explicitly stated "in this context" after I hit the Submit button. Pretty much a guarantee that somebody on Slashdot will fill in between the lines when there's nothing there to be read. Obviously it matters to those directly affected by it.

My point was that in the greater context, the world has decided that its nasty shit that shouldn't be sprayed anymore and put the issue to rest. Which isn't to say we shouldn't be vigilant for the next horrific action that somebody pulls off, but using events that old for anything other than teaching us to try not to repeat them is just grudge-holding.

Why are all these "pro-Science" people so horrible at basic arithmetic? Agent Orange was used (and manufactured) until at least1971. Is that really "70 years ago" according to your Science?

I'm not sure why you're bothering to equate math and science (though given your capital S I can take a guess..)

But aside from your hyperbole, I admit I was less clear on this one. The 70 years was an (approximate) reference to when AO was created rather than when it was last used. But since I was arguing that Monsanto's people in charge (and probably all of their other employees) have almost assuredly changed since that contract was signed, it seems like the more relevant date.

Everything a company does is "under contract". What do you think that even means?

It means that there's a difference between "here's a giant bunker full of money if you do something evil" and "I'm going do something evil because I feel like it."

And no, not everything a company does is under contract. Most successful companies perform their own R&D to create or improve products and services without waiting around hoping for someone to tell them what they should make next.

Remember this: When the US Government wanted the nastiest, most deadly chemical possible, who did they call? Monsanto exceeded the wildest hopes for deadliness, manufacturing 20,000,000 gallons of the stuff.

I'm sure they called every other company they thought would have the capability of delivering as well. The fact that Monsanto got the contract is a matter of history, not fate. If Monsanto had failed to deliver for whatever reason, we'd just be bitching about the next company on their Rolodex. Unless you can find some evidence that every other company pulled out for ethical reasons or something similar, there's simply no reason to single out Monsanto as anything but the "lucky" winner of the bid.

And do you really think that was the last deadly poison Monsanto made?

No. I'm sure they make thousands of deadly poisons. Most of them are useful for various industrial processes.

I can't begin to guess whether Monsanto knew at the time that their chemical was going to be used for warfare (probably could have at least guessed given the buyer and quantity if they weren't outright told..) I don't know whether Monsanto or anyone in the government expected the human toll of the chemical (it was designed to kill plants after all..) I'm guessing they probably had a pretty good idea of that by 1971 of course, but when they first developed it? Hard to say. Obviously at the very least there was some serious negligence in the safety testing if it wasn't explicitly meant to be toxic to humans, but negligence isn't necessarily evil in itself.

Overall though, my point is that focusing unnecessary rage on one specific company really isn't beneficial to yourself or the world as a whole. There's lots of shitty companies out there, and it was so long ago that Monsanto is effectively a different company today than it was 70 (or even 40) years ago. Should we just trust Monsanto then? Hell no! But neither should we distrust them any more than we distrust any other company of their size. All companies have to potential to be evil when there's enough money involved.

Comment Re:Cool Idea, Bra (Score 1) 269

A better model would be random partial replication between servers.

Not sufficient. My on-ramp server could potentially edit my post before passing it on for replication. I'm not sure if this is solved by your later comment about putatively authoritative servers or if that one only applies between the replication servers? I don't know enough about the iApple model to judge this one here.

It also requires a level of cooperation that's unlikely between competing players. I have little doubt that had usenet been created today that it would be a boxed-in system with a few large competing players each running their own newsgroups rather than the flood fill model it currently enjoys.

This interferes with the "I want to be able to unsay stupid stuff"/"I want to be able to use the server while high or drunk and fix it later" feature

No it doesn't. If the protocol includes a "delete message X" command and all of the replicating servers are honest, then the problem is solved (and essentially all of the servers would need to be honest -- at least in terms of the public-facing view of my profile -- or they'd face their own pressure to shape up under threat of being dropped from the replication pool by the other servers.)

But it solves the "domain name hostage" problem for profiles.

Again, its likely a "delete entire profile" command would be built into the protocol. Though in this case the pressure against servers would be to NOT to something evil like pass an unrequested delete around for replication, so you are correct that it should mostly solve the problem over the long term.

Comment Re:Distributed social networks won't work. (Score 1) 269

You're being disingenuous, or intentionally obtuse.

Intentionally obtuse. The only difference between putting my rant on a server I host and a server Facebook hosts is that I don't have to deal with someone else' system and ToS and such. It doesn't make one scrap of practical difference in the world if my url is www.thisiswhereirant.com or www.facebook.com/thisiswhereirant. Well OK, one difference. FB gives me a little bit of exposure that I wouldn't have on my own site (via friend-of-friend linking.)

That more of a consequence of the inability of the journalists to classify it

What? I'm pretty sure someone could have come up with "impermanent social media" if the permanence aspect was something anyone cared about in relation to the term "social media." But they don't.

I'm starting to wonder if you're interpreting "social" as in "socialism" rather than as in "socializing." That would explain a lot. Most people (myself included) think about the latter when they discuss "social media" though.

I think I pretty much want to out Bob as a Nazi everywhere.

Ok so your next post is "Bob's a Nazi jerk so I defriended him and you all should too!" Right after defriending him. Wow. That was hard.

If you want to take on a dedicated mission against Bob well then you're welcome to do that, but that's going well beyond the scope of social media and into the realm of maybe you being a bit crazy as well.

Younger users accept *all* friend requests. If it turns out they don't like what the person is saying or doing, they "unfriend" them later.

And that invalidates my argument exactly how? At the end of the day, the jerk is still not a friend (in either the real life or social media sense of the term.)

I think you haven't been following the whole GamerGate sock puppet situation very closely.

Again, that's relevant exactly how? Just because an ingrained problem happened to be exposed via a particular medium doesn't mean its intrinsically tied to that medium. Sexism was alive and well in gamer culture long before anybody made the first terrible post.

Once you are inside the web of trust, you're inside, and even if someone wants to not hear from you

That's what defriend and ignore are for. Bob might still be in my friend-of-friend "web" and perhaps you'll still see the things I post on their wall (or equivalent) but I don't have to see any of Bob's rants myself. If my (remaining) friends want to continue seeing Bob then that's up to them.

This is, in fact, precisely how the TOR network had been infiltrated by various third parties: peer-of-peer implied trust relationships.

Again, not sure what this has to do with anything. The fact that the TOR design turned out to have flaws doesn't mean they can't be corrected.

It also has little bearing on a decentralized social network unless that network piggybacks on the TOR protocol or intentionally makes the same mistakes TOR did.

Finally keep in mind that while the profile itself would need to rely on a computer-to-computer web of trust, what you as a person actually see would be based on your friends list and associated preferences. Bob's profile may well be stored on your computer as part of the protocol but that doesn't mean it ever has to be visible to you. Once you defriend him it just becomes another anonymous profile that you're only storing for the sake of decentralization.

Comment Re:We had a distributed social network (Score 1) 269

And when you're getting 10,000 of these "friend" requests daily? Even if you never hear from any specific one again that's a hell of a lot of BS to wade through if you're doing it manually.

You can argue about how transparent the algorithms "should" be or what particular algorithms to use or other technicalities, but its pretty hard to argue that you don't need them at all given that we know spammers and trolls exist and aren't going away any time soon.

Comment Re:Even 100,000,000,000,000 is too small (Score 1) 223

Right. And if the second factor is a fingerprint, having my fingerprint only means that you've cloned my fingerprint (or cut off my finger.) It doesn't prove that you are me.

The idea isn't to guarantee perfect security (that's impossible.) The idea is to provide a minimal level of guarantee.

In this case, its very unlikely that you both know my password AND have grabbed my keyfob, unless I've specifically allowed you to do so. You can lose a keyfob sure. But that by itself tells you nothing.. not even what account its for generally and sometimes not even what site/program.

Similarly you can have your password stolen (keylogger or whatever) but without the keyfob, that password is similarly useless.

Hence two factor -- one factor is something you know (the password) and the other factor is something you have (the fob.) Either one could be obtained by an attacker with (relative) ease, but BOTH being obtained at the same time is fairly unlikely.

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