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Comment Re:Not the quantum mechanical multiverse (Score 1) 458

would particles have formed differently, or at all?

Many different outcomes are possible. It's not due to "energy vibrating at different frequencies" - energy does that anyway, every color of visible light you see is energy vibrating at a different frequency, for example. But during an event like the Big Bang, properties of the universe that we observe as constants or laws today could have turned out differently.

Victor Stenger describes it as follows near the end of his 1990 paper The Universe: the ultimate free lunch:

Rather than representing order, symmetry principles actually correspond to a state of high disorder; they describe situations where no particular axis is preferred and thus a system has no structure. Order is not symmetry - order is broken symmetry. It occurs as the result of a phase transition from more symmetric but less orderly states, as with the freezing of a cloud of water vapour into a six-pointed snow-flake. Force laws result from broken symmetry.

Those phase transitions as an early-stage universe cools could lead to different force laws, among other differences, in the resulting universe.

Comment Re:If you accept those things ... (Score 1) 458

The article is discussing a consequence of some of the most well-established scientific models in existence: general relativity, quantum field theory, and the Big Bang cosmological model. That knowledge is what allowed the computer you're using to be built, and what allows GPS satellites to work. Those models make predictions which have been tested over and over and found to be accurate. The article is describing another prediction of those models. Your argument from incredulity (a logical fallacy) is nothing but a reflection of your own ignorance.

Comment Re:multiverse != multiple observable regions in sp (Score 1) 458

There's no standard definition for the term "multiverse", because it's not a term that corresponds to any established physical theory. The theory described in the article has a good claim to the term multiverse, because it's much more than just separate regions.

The region of the universe we're in almost certainly extends beyond the limits that we observe, so there are already "separated observable regions" in the universe we know. The article is talking about a scenario in which multiple Big Bangs occur, so each region is not just separated by distance but also by the nature of the space in that region - how much it has inflated, how fast it is inflating. Each such inflating region is possibly also distinguished by different laws of physics in that region. There would also be non-inflating regions which would have properties different from anything we're familiar with.

Back when other galaxies were first discovered, they were originally referred to as "island universes". This eventually changed to "galaxy" as our understanding of the extent of the universe shifted. If the theory in the article were somehow confirmed (difficult!) then in future, we might indeed refer to that larger space as just "the Universe", and refer to the inflating bubble we're in as something less all-encompassing than "the Universe". For now, though, it would be very confusing if we started referring to speculative constructs way beyond our ability to observe as "the Universe". Multiverse is as good as a term as any.

Comment Re:My God... (Score 1) 458

I spent a good bit of time trying to explain this to laycreatures

Sounds like the blind leading the blind.

You can't naively apply Popper in this case (who in any case is by no means the last word on philosophy of science), because the situation is quite complex: the article describes a possible consequence of existing established theories, including quantum field theory, general relativity, and Big Bang cosmological models. As such, Popper's rules don't say anything about those theories not being science, or whatever.

While it's true that "the math does not lead only and exclusively to that conclusion", it's a valid possible conclusion. As such, given the status of the theories that it's based on, we can't avoid taking it seriously as a possible description of reality. The task then becomes to discover if there's any way to improve our certainty about its correctness or lack thereof, and that's why people like Linde write papers about this stuff. Rejecting this as "not science" or whatever based on one particular view of what science is, is terribly short-sighted, and it's lucky that actual scientists don't pay attention to such nonsense.

One of the interesting consequences of eternal inflation style theories is that in principle, it addresses questions of fine-tuning. One can take the "evidence of fine tuning" as an argument in favor of multiverses in some form. From that perspective, the idea that our observable universe that started with the Big Bang is the only universe is actually the more difficult theory to defend, since we don't know how some of the parameters managed to come out on the knife-edge of allowing the universe to expand to a useful size and have useful properties like the ability for matter to form.

Re Popper, you should look into Imre Lakatos, who pointed out various flaws with basing all of science on falsificationism. See e.g. The Methodology of Scientific Research Programmes.

Comment Re:You mean (Score 1) 458

The "big bang" is the flat earthers looking out at the horizon, the most distant photons they can see... "yep, that is as far as we can see, it must be the edge of everything!"

No cosmologist says that. The edge you're referring to is the edge of the observable universe, nothing more.

If you *heart* science but suck at it, be a troll.


Comment Nukes good theoretically; practically, not so much (Score 0) 345

Nukes are theoretically safe and efficient. As I understand it, there's not enough known uranium sources on Earth to power the world, but in conjunction with solar, wind, hydro and bio-fuels (preferably from waste) there's enough.

Unfortunately, theories don't build nuke plants. Corporations do. And we can't manage to regulate large retail stores to make them behave in a socially responsible way, why do we think we can regulate a giant power company? Japan generally comes across as a competent, long-term thinking country. And yet even their political culture couldn't prevent fraud and corruption in the building of their nuke plants.

Until our political systems can effectively regulate large corporations, I'm opposed to nuclear power. The theory's great, but so far I don't see designs that can survive large-scale corruption.

Comment Re:In the SIMULATOR? (Score 1) 270

It's coffin corner because it's relatively easy to stall there, not because the aircraft could go too fast and break up. There is little risk in immediately descending. Certainly, the risks of stalling are far magnitudes greater.

My source: A retired jet pilot who had precisely the same thing happen to them as what happened to AF447 - iced up pitots and loss of airspeed indicators.

Comment Re:Why put the automation in if not to use it? (Score 1) 270

"ABSes have saved many lives when drivers slammed on the brakes to avoid a collision, or started slipping on ice." [citation needed]

If anything, the evidence is somewhat to the contrary. Studies on taxis with and without ABS (the cabs are otherwise very similar vehicles), showed that ABS equipped cars did not have lower accident rates overall. Indeed, certain types of accidents, e.g. in snow, where significantly higher for ABS equipped cars. Cite:

Comment Re: self-flying planes (Score 2) 270

The computer did not give any instruction. The computers went into alternate law (i.e. "act dumb, do 100% what the pilots command") precisely because the computer had detected sensors were giving conflicting readings. It was down to the pilots to determine what was needed to be done. The correct course of action was fairly obvious. They were flying at altitude, where maximum speed and stall speed are very close to each other. That is, any significant loss of airspeed risks stalling and disaster. The correct course of action, if there's a problem with airspeed indicators, then is to ensure airspeed is preserved - i.e. descend. This is real 101 stuff when it comes to "Flying high".

The senior co-pilot, in command at the time, knew what had to be done, so did the captain (who was not on the flight deck initially). Unfortunately, despite both of them clearly ordering the junior co-pilot to descend and, later, leave the fucking controls alone (though, by that time, they were almost certainly doomed), the junior co-pilot inexplicably kept taking control and ordering the aircraft to climb - precisely the wrong to do. What was going through his mind we will never know.

Comment Re:Could this story please die (Score 1) 130

MAC addresses are useless for tracking pretty much anything except on a LAN (and even then they're pretty useless - particularly with virtual machines becoming more prevalent). In addition MAC address info ages out insanely quickly. Half the MAC addresses in my house post-date the street view car passing. And in fact several others aren't here.

ESSID info is useful for geolocation, but even it rapidly ages. And Google is hardly the only company that sniffs that.

And Microsoft applications bleed private info far more sensitive than MAC addresses. I once got a job offer as a Word document which also contained job offers for four other people. Some versions of Word and Excel save random bits of RAM into docs. Honestly if you're using Microsoft products and expect to have any privacy you're an idiot.

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