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Comment Re:To everyone whining about the title... (Score 1) 109

What about the "Independence Party of Georgia"? As far as I can tell, this list is the only evidence of their existence (unless the State of Georgia is sending personal information to a political party in the Republic of Georgia, which would be an interesting development).

Comment Re:Space stations (Score 1) 378

"Earths space and resources will deplete, and we could build a large rotating space station even with today's technology."

Sure, we *could*. But are you willing to pay for it? Personally I think there are better things to spend a few trillion on down here on earth. And no, I'm not a luddite going down the "there's starving kids and yet we spend money on space" argument. But an orbiting station is not an end in itself - it needs a purpose other than just being the worlds most expensive funfair ride , and until we come up with a better space motor than chemical rockets humans ain't going anywhere further than the moon anytime soon.

It is becoming clear that going to Mars will require the development of some sort of resource infrastructure in the near-Earth asteroids (as well as at Phobos). The travel times to Mars are so long and the demands of space travel so hard that going there means you are going to stay (or maintain a more or less permanent base) and that will require a supply chain that extends off our planet.

Now, another way to say that is that the economy will have to extend off of the planet for us to go to Mars at all. Once you do that, people will follow. I see that as inevitable - they will have the technology to do so, there will be economic reasons to do so, it will happen. But, spreading economies open up even more economic potential. Once it starts, it will not just spread, it will start increasing exponentially. After a while, it becomes its own justification, in much the same way that the economic viability of New York no longer depends on what raw materials it can provide Great Britain.

Comment Re:Information is lost (Score 1) 152

I don't follow that - I interpret "issue of information loss" as meaning that it is happening - i.e., that there is loss to worry about. Read at the bottom of page 1

Furthermore, the entanglement implies that the outgoing Hawking particles cannot be entangled with one another at various times. This shows
that there is indeed an issue of information loss in a black hole, within the semiclassical approximation

Entanglement survives across the event horizon (at least, in this analogue). It would be presumably destroyed at the singularity. There is (at least, in this analogue) no black hole firewall, no entanglement with previously emitted particles, no wormholes or other such exotica.

As for the frequency dependence, I will wait on that. That may be profound, or it may be an experimental error or some restriction imposed by the black hole analog setup. We should know soon enough.

Comment Re:According to the one that left (Score 1) 152

This i understand this far.

So now, i have this black hole that i can't see. I send an object toward it. From my perspective, time slows to a halt on the sent objective at the event horizon, so it looks like it never enters. So it actually stays visible, right? Over time, the black hole would look like a big ball of stuff frozen in time? What am i missing here?

The red shift. Drop a flashlight down into a black hole (you'l need a big black hole so that tidal forces don't destroy the light on the way in). As it falls, the red shift increases rapidly and so the flashlight both reddens and dims rapidly. (That is, fewer photons per second AND each photon has lower energy.) After a short time near the event horizon, you will receive the last photon you will ever get from the flashlight - and the same is true no matter how bright the light. So, no, it is no longer visible as it falls in.

Comment Re:Ah, arXiv (Score 1) 41

If you are unable to contact the organizer of a workshop when something like that comes up and work out an alternative when needed, then you will likely have much bigger problems.

I was actually thinking more about the organizers than the submitters (I have organized scientific meetings). One reason why organizers like this is that the arxiv paper submission is part of their automated submission process (i.e., they don't have to set up a paper hosting service, arXiv does it for them). This means that there is a real risk that arXiv is involved in their Editorial process, and that they might not even know it, and I think most conference organizers would find that unacceptable.

Comment Information is lost (Score 3, Informative) 152

What I think is the really important thing in the original paper is that information actually seems to be lost in the black hole. There is an enormous amount of theoretical musing about how to prevent information loss at event horizons (remember the black hole firewall?); this, if taken seriously, could have implications in quite a number of areas in theoretical physics.

Comment Re:Ah, arXiv (Score 2) 41

I have never heard of this, and I am interested. Can you name an example of a respectable scientist (not a "fringe" controversial person, I mean) who has been banned?

Marni Sheppeard.
Peter Woit.

Note that they are not (as far as I can tell) banned, just blocked. Nothing is made public, it's just that certain things seem to happen consistently. And, in my experience, moderated papers are not available to the public.

Note that the real problem here is not that papers are moderated. I understand the desire for moderation. It's the way it's being done that is problematic.

Comment Ah, arXiv (Score 4, Interesting) 41

You do know that some people are blocked from arXiv, and at least in some cases there is no obvious reason why (and no real appeal)? (Opponents of string theory, for example, seem to get this, or at least complain about this, fairly often.) I have seen this in action, it is real and it is capricious.

I do not think that arXiv is suitable for a filter for a public meeting as long as its internal filtering is opaque in this fashion.

I have a theory that it's impossible to prove anything, but I can't prove it.