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Comment: Dark Matter, Dark Energy, common cause? (Score 1) 293

by error_logic (#45285103) Attached to: Most Sensitive Detector Yet Fails To Find Any Signs of Dark Matter

This has been bugging me for years, but I don't understand enough to either substantiate or falsify my thoughts. I also don't want to try and convince people that it's right since it sounds crazy even to me, but please tell me if you can find something wrong with it... I know that there are some extensive theories and observations involved, and I'm very aware of the relevant xkcd... http://xkcd.com/675/

All that said, it's very interesting to consider the possibility that there's a common cause of the observations that prompted dark matter/energy theories. I've read far too much about physics on Wikipedia trying to disprove the notion, with little success. All I've managed to do is find more and more curious aspects of things that would be *solved* by the idea.

I'd be very interested in someone finding evidence to falsify the possibility of dark matter and energy sharing a common anti-gravitational cause. I've been trying to find a contradiction for a very long time, and have found nothing conclusive.

If we consider that the anti-gravity could be caused by the missing antimatter purportedly absent due to baryogenesis, we might expect to find annihilation emissions in the spectra (Hmmm... http://en.wikipedia.org/wiki/Space_roar ? Doubtful, but who knows?). However, such an observation could be absent for at least two possible reasons: It doesn't exist...or the bulk of the antimatter is something weakly interacting and low-mass, sharing the same problem as the standard dark matter model.

I don't mean that antimatter would fall up in such a changed model. Its inertial mass could behave as expected, and follow spacetime the same way as normal matter. It would just exert repulsive influence. Galaxies would be compressed by rings (or spheres, how dark matter is modeled?) of antimatter surrounding them and spread out somewhat in intergalactic space (dark matter), while being repelled from each other by the spherical gravitational dipole effect (dark energy).

If you model a binary system with one matter and one antimatter particle, they orbit a barycenter on the opposite side of the matter particle from the antimatter particle...in lock-step with each other. Put a black hole at that barycenter, add more particles of each type, and you get an orbiting system that goes much faster than it should from just the matter...just like dark matter's effects on galaxies.

There's some amazing symmetry if you think about this, and some weird implications. Inertial and gravitational mass would no longer be identical. Relativistic mass might be gravitationally neutral. An antimatter particle would chase a matter particle and require new interpretations of conservation of energy (Probably one of the biggest potential arguments against the whole concept, except it violates assumptions, not any evidence I'm aware of).

My most recent consideration from all this was the idea of applying CPT symmetry to the big bang (since it could be expected to involve both matter and antimatter), with some truly crazy implications. Unfortunately my understanding of it seems to be even more lacking than I thought, and I'm not sure how to mathematically formulate/test the possibility of the Universe sharing a common beginning and ending if you look at matter and antimatter versions in opposite time-space terms.

I don't know what I'm doing, and really wish someone could put this musing to rest one way or another. Unfortunately, I doubt we really have the experimental evidence either way. All of my musings amount to relaxation of assumptions--I haven't found a concrete contradiction, and all the predicted effects seem too subtle for current experiments to show.

If anyone could give good evidence for falsification of this common cause hypothesis, or point me in a direction for finding it, I'd be very appreciative. I've spent far too much time thinking about this with nothing to show for it, despite trying to break it.

Thanks for reading. Please get this out of my head. :P

Comment: Re:Just when you thought it was safe.... (Score 1) 398

by error_logic (#45154233) Attached to: Windows 8.1 Rolls Out Today

The taskbar button labels not showing up on a second display may be a feature to reduce screen space used. For some reason lately I had a glitch where the taskbar wasn't visible on the bottom of the screen but putting it on one side worked well. Surprisingly I've adapted to it, and now it makes sense to have just icons on the second screen's taskbar--it uses less space since the taskbar can be narrower horizontally.

I don't expect anyone to adapt to a side-positioned taskbar randomly, but strangely it works.

Comment: Re:"free" market solution (Score 1) 452

by error_logic (#44965847) Attached to: Undiscovered Country of HFT: FPGA JIT Ethernet Packet Assembly

You're going to have to do better than that to convince many people. It sounds like you're hand-waving in order to support the notion of middle men benefiting both sides by inserting themselves. I'd be interested if you could prove your points in a way that sounded less like you're presenting one side of the real story.

What is the fundamental source of a transaction cost?
You say it's related to the risk; is that just for short-term risk of people involved in holding stock for the purpose of connecting [slower] buyers and sellers?
The risk may be lower in the sense of maximum possible damages, but what about gains? Don't HFTs try to maximize profits, not just risk mitigation?

Doesn't that mean they're taking profit that would go to regular investors, ignoring the time required for more meaningful investment to pay off?

Finally, you speak of risk for the individual entity investing. Personal risk. Yes, if you can shift things around faster than anyone else, you can save yourself first. What about the market? Can you really say it reduces the risk of fluctuations as all the self-invested HFTs bail out, cratering the market value? Especially considering the aggregate risk introduced by such short term thinking as caused the housing crisis and many other bubbles?

Comment: Re:However (Score 1) 505

by error_logic (#44128473) Attached to: Hands-On With Windows 8.1 Preview

That is an advanced user shortcut, and it bundles a lot of advanced options in one place. Someone should have mentioned this earlier, but for the specific example of getting to the control panel from the Desktop: Charms menu->Settings->Control Panel.

And of course if you're on the Start page, you can just start typing and get it within a few keystrokes.

"Your stupidity, Allen, is simply not up to par." -- Dave Mack (mack@inco.UUCP) "Yours is." -- Allen Gwinn (allen@sulaco.sigma.com), in alt.flame

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