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Comment: Re:me dumb (Score 1) 130

by lgw (#49548161) Attached to: Wormholes Untangle a Black Hole Paradox

Well, there are several "kinds" of wormholes. In one, the distance really is 3 ticks, in every way that matters, and the fact that there's also a 10-tick path (which used to be the shortest path before the wormhole) means nothing, as there are an infinity of circuitous paths. But that's not this kind of wormhole.


To see the problem, imagine 2 wormholes, A and B, each with widely separated endpoints. In my reference frame, the endpoints A1 and A2 are stationary - I'm standing by A1 and can send a message instantly to A2. The endpoints B1 and B2 are stationary relative to one another, but are moving close to c relative to A. In B's reference frame, my message goes back in time.

If my message gets relayed A1-A2-B2-B1 just as the endpoints pass, I'll get it before I send it. In my reference frame, A1-A2 is instant, but B2-B1 goes back in time. In B's reference frame, A1-A2 goes back in time, and B2-B1 is instant. Either way, it's a causal mess.

A simpler example: you can get a straightforward time machine simply by accelerating one end of a wormhole up to relativistic speed for a few years, and then bringing it back, parking it at rest near the other end. Like the twin who visits a distant star and returns, one end will be "younger" than the other. Now the wormhole moves you back (or forward) in time by a few years when you traverse it.

Comment: Re:me dumb (Score 2) 130

by lgw (#49547911) Attached to: Wormholes Untangle a Black Hole Paradox

OK, I tried to read your first sentence 3 times, and I still can't parse it, so I'm not sure what you're saying. Naturally, slower-than-light state transfer doesn't introduce paradox. FTL state transfer does allow inversion of cause and effect - the clear examples of this involve two pairs of wormholes, moving quickly relative to one another, which allows you go send a signal out through one pair and back through the other, and get the signal before you sent it.

Comment: Re:me dumb (Score 2) 130

by lgw (#49547767) Attached to: Wormholes Untangle a Black Hole Paradox

It's early days for this idea. This is theoretical physics, so it's usual for it to take a while for someone to come up with a proper experiment. Compelling, convincing experiments that have demonstrated the Bell inequalities (the EPR paradox) really started in 1998, decades after the theory was broadly accepted.

This paper was more about black holes than quantum entanglement, and that stuff is harder still to test. It's the implications for QM that are really the exciting bit. It may well be that this is just a different explanation for the same phenomena, and so will remain "just theory" until we find some way to observe black holes closely. But if in fact it works out that this would be a modification to the mechanics of entanglement, someone will devise an experiment for it, as entanglement is still an area of interest for the experimental physicists.

Comment: Re:But I can still get piss drunk at the pub, righ (Score 1) 105

. I suppose you think we all still wear bowler hats and say 'what ho Jeeves'?

I met someone in a bowler hat just last week. He was also wearing a kilt. And a bright purple shirt. Picture that combination for a moment.

They key to unlocking the fashion mystery? Jury duty. Sure enough, he didn't get picked. Clearly he'd been living here for quite some time (long enough to be a citizen), so I can't hold him as representative of all the UK - I'm sure you don't all wear bright purple shirts.

Comment: Re:me dumb (Score 5, Informative) 130

by lgw (#49546839) Attached to: Wormholes Untangle a Black Hole Paradox

I can't explain the mathematics Leonardo is using (best nickname ever), but I can explain the basic idea.

Wormholes can connect two arbitrary points in spacetime - this allows FTL travel, but that means time travel, with raises all sorts of paradoxes. The current understanding of this style (ER bridge) of wormhole is that they're inherently unstable - the math allows them to form, but they'd collapse as soon as anything interacted with them.

Quantum entanglement says that two entangled particles have this oddball relationship that one somehow knows that the other has bean "measured" (any real interaction between two particles is a "measurement" in QM, it's not some special thing), in a way that's seemingly faster than light, but can't be used to send information.

These two ideas dovetail nicely - if quantum entanglement means the two particles are connected by a wormhole, which collapses the moment either is "measured" (i.e., any time they interact with anything new), then you have a way for that communication to happen FTL, an then the two particles are disconnected and no longer have any special relationship. You don't get time travel paradoxes, because it's the nature of entanglement that you can't use it to send data FTL even though the effect is FTL.

It sounds neat, but that almost counts against you in QM. The key is whether the math works. Exciting if true, however.

Comment: Re:Unity next (Score 1) 402

by lgw (#49546715) Attached to: Ubuntu 15.04 Released, First Version To Feature systemd

I use both Ubuntu and Red Hat daily at work. I really don't like the current Ubuntu desktop - it seems inspired by good ideas, but it doesn't deliver them. Red Hat's very old school desktop is straightforward and intuitive, if limited and ugly. But I'll take limited and ugly and can get work done over the alternative! (This is also my argument against systemd, of course).

I haven't seen XFCE in forever, but I remember it being really fast anf lightweight. XFCE with a taskbar would be my dream.

Comment: Re:Amazon has really been a stealth company (Score 1) 72

by lgw (#49546543) Attached to: Amazon's Profits Are Floating On a Cloud (Computing)

. I think there are very few companies, including profitable ones like Microsoft, that have that luxury.

I think any company can do the same, as long as they convince their large investors they have some sort of long-term plan that justifies it. While stock prices are batted about by people chasing quarterly results, those speculators aren't going to evict the board of directors, they'll just sell and move on. It's the large, long-term investors, the pension funds and mutual funds and so on, who will make the effort to cut the head off a company if they think the current board/CEO are fools. As long as they believe your plan will work, you can take short-term losses if you have the cashflow, or can borrow.

Microsoft is in a unique position that that have an insane amount of cash, can run at a loss for a decade without going under, and the long-term investors just cut the head off the company in favor of a long-term plan. They really have no excuse at all here.

Comment: Re:And it's gonna rain (Score 1) 72

by lgw (#49546483) Attached to: Amazon's Profits Are Floating On a Cloud (Computing)

Isn't AWS used for more than cloud storage and computing? It's also used for simple web hosting. Did they subtract the revenue from website hosting from that $1.5B figure.

AWS includes far more services than I've ever heard of. "Cloud computing" is EC2, which you could use for web hosting once you grow large enough to need a full VM (or 1000). I'm sure theyalso have some web hosting product somewhere for personal-sized sites too. All of that, plus the storage and so on - everything "cloud" - is AWS (I know of their queueing service and their load balancer service, but I've only looked for the obvious stuff).

The fact that it's collectively profitable despite the price wars should be a real wake-up call for anyone using "cloud" as a loss leader.

Comment: Re:Dead until 2016 or 2020 anyway (Score 1) 99

by lgw (#49546347) Attached to: Bloomberg Report Suggests Comcast & Time Warner Merger Dead

You do realize the real contribution from these companies are many millions, right? Except to the Clinton "charity" and a $300k speaker fees for Hillary, instead of on the books? (And it's not like the Clintons are especially corrupt here, compared to the rest, though they're more brazen than most about it.)

Comment: Re:What is a "feet"? (Score 1) 127

by lgw (#49544907) Attached to: I spend most of my time ...

There's only One True System of measurement: the Furlong-Firkin-Fortnight system. One "foot" is very close to 1.5 millifurlongs. One "meter" is very close to 5 millifurlongs. Silly antiquated systems.

For convenience, some people still use the archaic measures: 100 millifurlongs is a "chain", and 1 millifurlong is a "link" (one link on the aforementioned surveyors chain), and 25 millifurlongs is a "rod". Much easier to say than "millifurlong".

The other standard units in the "F you" system are of course the Farad and the degree Farenheit. All units have the standard abbreviation F, which makes dimensional analysis so much easier - the answer is always "F you"!

Comment: Re:Dead until 2016 or 2020 anyway (Score 2) 99

by lgw (#49543049) Attached to: Bloomberg Report Suggests Comcast & Time Warner Merger Dead

The opposition party has obstructed the president 10 times as much as his own party has obstructed him? You don't say.

It's past time to stop caring about the "Democrat" or "Republican" labels! What matters is, on a critter by critter basis, which specific congresscritter is in the pockets of which specific corporations. Stop voting based on party, stop voting based on ridiculous emotional appeals about what sexual practice will be mandatory or forbidden, and pay attention to who owns the specific candidates. It's reasonably public, if we choose to care, and while every congresscritter may be owned by someone, there are plenty of corporate political agendas I don't give a fuck about (e.g., luxury taxes on yachts), and plenty that affect my life directly, and voting on that basis matters.

Comment: Re:Dead until 2016 or 2020 anyway (Score 3, Insightful) 99

by lgw (#49540471) Attached to: Bloomberg Report Suggests Comcast & Time Warner Merger Dead

Republians? Surely you jest. Take of the partisan hat and look at the actual data for Hillary Clinton, presumed Dem presidential candidate.

Her top 10 career donors are mostly investment banks (all the big names are there), but Time Warner and Cablevision make the top 10.

Will we get a GOP candidate not already in the pockets of investment banks and cable companies? I'm not holding my breath, but it's theoretically possible, unlike the Dem side which is already bought and paid for.

Money is the root of all evil, and man needs roots.