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Physicist Kip Thorne On the Physics of "Interstellar"

ardor Re:You will not go to wormhole today. (289 comments)

> Also, how are you applying the many worlds theory? Aside from the fact that it's not universally accepted, and the fact that I don't have a clue how to falsify it, it applies to phenomena that could go more than one way. When I measure the spin on an electron, there are two possible values. The many worlds theory says that there are now twice as many universes, half with spin one way and half with spin the other way. Are you claiming that, when I drop a banana, there are universes where it falls and universes where it doesn't?

This is correct. Note that Many Worlds is not a theory, but a QM interpretation. But you correctly described how it would be applied. What can happen, will happen, in one of the infinite number of universes. The trick is to see all frames of reference over all universes. This way, there really are no preferred ones (in other universes, you do the FTL travel, so you enter these frames of reference, and then a causality violation happens in these universes). If you just look at the frames of reference of your universe, then yes, there would be a preferred one.

The actual problem is that Many Worlds is an interpretation of quantum mechanics, and nobody has ever actually attempted to combine it with special and general relativity, both because Many Worlds is (currently at least) not falsifiable, and because QM and relativity have fundamental incompatibilities, which need to be resolved anyway. So it's all speculation at this point. For instance, "all frames of reference", does this extend to all frames of all universes or not? It is unclear without merging.

about three weeks ago
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Physicist Kip Thorne On the Physics of "Interstellar"

ardor Re:You will not go to wormhole today. (289 comments)

No, we can observe this other FTL travel as well, but *then*, the universe in which it is observed ends. "It is impossible to observe", on the other hand, would mean that it cannot happen in *any* universe. From the point of view of our universe, you are right, it does appear as if some types of FTL travel are disallowed. But this is solved by allowing them to happen in general, and just the ones where it didn't happen "survive". So, these other types of FTL travel only appear to be disallowed, they aren't really disallowed.

Another example would be a spontaneous transition to a lower quantum vacuum state. It is highly unlikely, but could happen. With the many worlds interpretation, it spontaneusly happens in some universes, which then end, or at least we aren't around to observe it. In others, it doesn't happen, and we are still around to observe these universes.

about three weeks ago
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Physicist Kip Thorne On the Physics of "Interstellar"

ardor Re:You will not go to wormhole today. (289 comments)

No, they *can* happen, but when they happen, the universes cease to exist. The many worlds interpretation then implies that only those universes where these things *didn't* happen survive. It's not about forbidding certain events, its about how precisely these events prune universes.

about three weeks ago
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Physicist Kip Thorne On the Physics of "Interstellar"

ardor Re:You will not go to wormhole today. (289 comments)

To be exact, a scientific theory is not just an idea, it is a rigid and solid mathematical framework that has been demonstrated to hold up scrutiny.

about three weeks ago
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Physicist Kip Thorne On the Physics of "Interstellar"

ardor Re:Faith based Order (289 comments)

> That's the scary thing about people with some education but not enough, they think they know FAR more than they really do and are more than happy to attack anything they think the people "above them" don't agree with even if they aren't qualified to do so..

Yep. That's the Dunning-Kruger effect in action.

about three weeks ago
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Physicist Kip Thorne On the Physics of "Interstellar"

ardor Re:You will not go to wormhole today. (289 comments)

> There are solutions to GR equations which allow for spacetime to be bent to the point where something that *looks* like FTL to fall out, but they tend to require exotic matter, and there's no evidence to suggest that said matter exists.

This is the big one. Alcubierre's metric has been heavily optimized over time to require energy amounts that could be feasible one day, but the exotic matter bit is the second problem. We can only hope that (a) exotic matter exists (b) an alternate solution can be found (perhaps something based on dark energy once it is understood).

As for the frame of reference, perhaps this isn't such a big deal. If for example the many worlds interpretation is valid, and a causality violation leads to some sort of breakdown of a universe, then you simply would never notice them, since the universes where the violation did happen just cease to exist. So, if a spaceship FTL-flies from A to B, B is a planet in movement relative to A, and the ship FTL-flies back to A, perhaps in the "surviving" universes it flies to A slower for example.

It's all hypothetical of course, but it shows that the causality problem could be circumvented.

Then again, we shouldn't be talking about FTL if we don't event have (relatively) cheap and commercial mass transportation to LEO and beyond yet. The sun won't increase its luminosity to lethal levels for the next 700 million years or so, so we have time.

about three weeks ago
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Halting Problem Proves That Lethal Robots Cannot Correctly Decide To Kill Humans

ardor Re:I think (335 comments)

The former if any incident involving a killer robot that went haywire results in huge penalties and murder sentences I guess..

about a month ago
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Virgin Galactic SpaceShipTwo Crashes

ardor Re:Brutally sad day (445 comments)

> You can improve safety, which is always a good thing to do, but improvements will be asymptotic to a value below perfectly safe.

To be exact, this is true for *everything* in life. There simply is no such thing as "perfectly safe".

I do agree with your posting though.

about 1 month ago
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Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

ardor Re:What you missed above - so much really (226 comments)

Great. Name calling, with zero actual substance. I am reminded now why I don't frequent Slashdot much anymore. I suppose you can't be bothered to bring actual arguments against what I wrote in my earlier, post, right? No, spitting out curses is much easier of course. It should be completely obvious that I am *not* speaking for Raster, but instead am stating that he *would* agree with what I said since his design decisions for Evas are pretty much what I described. But hey, I don't expect an actual discussion anymore. Continue with your infantile name calling.

about 2 months ago
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Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

ardor Re:What you missed above - so much really (226 comments)

If you mean enlightenment evas, note that the lead developer would agree with me. Evas has been one of the earlierst adopters of client-side drawing. It is so efficient that it can even outperform GL-accelerated 2D drawing in certain cases. Evas has (or had) support for the Xrender extension as well, but quickly dropped that, because letting the application handle all of the drawing and small-bitmap blitting (by that I mean stuff like icons) is so much more efficient. If anything, Evas is a perfect example of why the "blitting bitmaps" paradigm is the better one.

about 2 months ago
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Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

ardor Re:Let's please stay on topic (226 comments)

And none of them use the X way of remote desktop either. Yet, they are efficient, and in heavy use. You make it sound as if remote desktop is unfeasible without the X remote functionality, which simply isn't true. Stick VNC/RDP to Wayland, and you are done.

about 2 months ago
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Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

ardor Re:What you missed above - so much really (226 comments)

Again, I wrote:

Yes, that fits the term "most", unless you are running some old distro

Also, you completely disregard the MUCH bigger number of administrators and helpdesk personnel working with VNC, RDP, Citrix etc.

You said it yourself: the X remote functionality is okay for *old* stuff (RHEL5 is from when, 2007?), which still draws content by asking X draw this line, that text etc. It is much more efficient to let the application draw these things by itself these days, which is why every newer toolkit and application uses this client-side drawing model. And this is *exactly* where X is broken: it is fundamentally ill-suited for this new paradigm, which only needs a much simpler system. One like Wayland, which only provides surfaces applications can draw into. That's it. Anything else is an anachronism.

about 2 months ago
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Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

ardor Re:Why? (226 comments)

Qt4 just pushes bitmaps (even Qt3 did, partially). So does Gtk 3. So do Chromium and Firefox, and IIRC also Thunderbird. Yes, that fits the term "most", unless you are running some old distro.

about 2 months ago
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Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

ardor Re:Why? (226 comments)

assuming it's not trying to do things with drm

Which is what 99,99% percent of all modern OpenGL applications will do.

about 2 months ago
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Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'

ardor Re:Why? (226 comments)

IMHO, the point of X network transparency is a no-brainer in the same way as local OpenGL acceleration. Instead of wasting bandwidth on raw bitmaps, you just send the drawing commands, whether over the network or PCIe. (It's like MIDI vs. raw audio for the keyboardists out there.) I don't know all the programming details, but I've done 3D modelling over 2 MB/s cable this way, and I can't imagine it would have worked as smoothly using raw video.

You are talking about indirect 3D rendering, which is a fundamentally different topic. It is true that you can in theory send OpenGL command streams over a network, but in practice, this works only for certain applications, where the size of the commands is not too large, and no large assets (textures, meshes) etc. are transmitted. There's a reason why everybody wants *direct* rendering for 3D on the local machine. Forget about running games with indirect rendering, for example.

But when it comes to 2D applications, it quickly becomes obvious that the X protocol is useless nowadays, since most application draw paths, fonts etc. on their own, and X only gets to handle window-sized pixmaps. X drawing commands are almost never used anymore, except by some ancient stuff, like xterm. In that case, that fancy "X11 transparency" will end up transmitting raw bitmaps over the wire. Just use RDP, VNC etc. instead.

about 2 months ago
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The Almost Forgotten Story of the Amiga 2000

ardor Re:It was pretty cool in its day (192 comments)

For gaming, why not just run the PC-versions of Dune, Monkey Island and Settlers? They aren't exactly the same but is the difference really that important?

One reason is that back then, many DOS versions of games only had AdLib or even just PC speaker support, while the Amiga version came with fully digitized audio.
Compare https://www.youtube.com/watch?... to https://www.youtube.com/watch?... , https://www.youtube.com/watch?... . (The sound is actually in stereo, but the Youtube videos are downmixed for some reason.) The difference can be jarring thanks to the inferior music.

As a matter of fact, the Amiga was famous for its sound (and graphics) capabilities back then, *especially* compared to DOS. (Well, until 256-color VGA became common..)

Some DOS games had digitized audio as well, but Amiga could mix 4 channels in hardware. Mixing had to be done in software in DOS, unless you had something like a GUS or an AWE32 sound card.

about 5 months ago
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'The Door Problem' of Game Design

ardor Re:Will the door have windows? (305 comments)

But you forgot to use an XML schema for validation, and XSL transformations to be able to automatically write a game out of the XML files!

about 8 months ago
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An SSD for Your Current Computer May Save the Cost of a New One (Video)

ardor Re:Max RAM? (353 comments)

But even if it consumes less RAM, browsers do a lot of I/O, because they cache all these images etc. so if your disk cache is almost nil, you will notice.

about 9 months ago
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An SSD for Your Current Computer May Save the Cost of a New One (Video)

ardor Re:Max RAM? (353 comments)

It consumes almost all of the physical memory. free -m also shows that the RAM is full, even when taking cache into account. Also, it uses about 1GB of swap.

about 9 months ago

Submissions

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IFPI wants EU to censor the Internet

ardor ardor writes  |  more than 6 years ago

ardor (673957) writes "According to this position paper, the IFPI desires extensive regulation and censorship of the Internet in order to combat piracy. They want to see this accomplished by:
  1. content filtering via "audio fingerprints"
  2. protocol filtering by blocking entire protocols they^H^H^H^Hthe ISPs estimate to be mostly used for illegal content (read: tor, torrent, eMule...)
  3. blocking of "infringing" sites
Since France already has draconian censorship of the Internet, how long until the IFPI fully prevails?"

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