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Comment Re:MOS? (Score 1) 37

There is a video of the codec vs. SSB on the same radio link here. You can also take any radio links you have at hand and run the FreeDV program. This is an evening project to set up without a business case, and at least some companies appreciate people who take the initiative to do this sort of thing.

Comment Re:1200 bits/s, not bauds. (Score 1) 37

Sorry. When I say "1200 Baud", I am in general thinking of the TAPR TNC 2, which was never built for voice but can do it, to a degree, with this codec. It's sort of a Bell 212 modem on half-duplex radio. There were many commercial products based on the TNC 2 design and many hams have them on hand. It's a good demo to put speech through a pair of them, not really practical because the latency is high.

Comment Re:MOS? (Score 1) 37

MOS is only for people who want to pay a lot of money. Of the automated processes, the one available to us isn't validated for less than 4K bps codecs.

It would be a great improvement to MOS if there was an open version of POQLA. But the actual customer base for the codec have never even heard of MOS and thus we aren't volunteering to write that. The folks who want to put it in expensive government support systems yet aren't willing to help with testing don't get our sympathy.

Comment Re:Code2 voice sample @4:50 (Score 1) 37

We avoid some techniques that would make the noise performance worse. The HF version of the codec doesn't vector quantitize, and doesn't do any delta coding between frames. The current FEC is Golay and we are investigating low-density parity codes.

There is a lot yet unheard about the Ratheon codec, regarding its actual noise performance and how well the listener can distinguish different speakers.

Submission + - Three Videos on Codec2 and Open Hardware

Bruce Perens writes: Codec2 is the Open Source ultra-low-bandwidth speech codec capable of encoding voice in 1200 Baud. FreeDV (freedv .org) is an HF (global-range radio) implementation that uses half the bandwidth of SSB, and without the noise. Here are three speeches about where it's going:
  • David Rowe: Embedding Codec2: Open Source speech coding on a low-cost microprocessor, at Linux.conf.au 2014. YouTube, downloadable MP4.
  • Bruce Perens: FreeDV, Codec2, and HT of the Future (how we're building a software-defined walkie-talkie that's smarter than a smartphone), at the TAPR/ARRL Digital Communications Conference 2013. Blip.tv, YouTube
  • Chris Testa on the .Whitebox handheld software-defined radio design that is the RF portion of HT of the Future, which was also shown at the TAPR conference.

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.

FTFY

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