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Comment Re:So what should the family do? (Score 1) 263

The escape velocity of a neutron star is about 1/3 the speed of light --- and getting mass to 1/3 the speed of light is absolutely impossible.

Actually, you can get mass to within a whisker of the speed of light right on your desk:

Comment Re:So what should the family do? (Score 1) 263

The paper isn't really about how an astronaut would die. It is about the nature of the interface between the inside and the outside of the black hole.

This is interesting because it has applications to cosmology in general. In fact, many (perhaps even most) of our cosmological models have their origins in the study of the theory of black holes and, particularly, the study of event horizons. This makes them fundamentally more interesting to study than neutron stars and the like to many cosmologists.

Comment Re:Spaghetti (Score 3, Interesting) 263

A black hole would eventually stretch a person into spagetti, but not necessarily near the event horizon. For a small black hole the effect might be well outside the event horizon while for a supermassive black hole the effect would be well inside of it.

This is because the event horizon of a super-massive black hole is so large that while the gravitational pull there is enormous, the variation in the graviational forces in a human-sized volume is quite small. It's the variation in the forces that stretches you.

Likewise, while the total gravitation pull well outside the event horizon of a small black hole is much less than the total gravitational pull near the event horizon of a super-massive one, the variation is much higher.

Comment Re:Hmm (Score 1) 530

If time is an emergent phenomenon, then how does the first event happen? If time does not yet exist, then there is no was to distinguish an event. By the parent's suggestion, time can only be propelled forward when already in motion, by the contribution of each new event.

All I can say is that the Page-Wooters paper suggests that time does not, in fact, work this way and this current paper, if correct, provides evidence that Page and Wooters may have been right about it.

Comment Re:Hmm (Score 1) 530

The paradox comes about because I used the word "observe" in two different contexts. From the abstract: "We implement this mechanism using an entangled state of the polarization of two photons, one of which is used as a clock to gauge the evolution of the second: an "internal" observer that becomes correlated with the clock photon sees the other system evolve, while an "external" observer that only observes global properties of the two photons can prove it is static."

Comment Re:Hmm (Score 5, Insightful) 530

The theory requires no outside, God-like, observer, nor does it propose one. The point is that time is measured by "events" and "events" occur when the quantum states of two systems become entangled, but only to the systems that became entangled. To an "observer" that has not become entangled, a system is static and no event has occurred.

In the Copenhagen interpretation, one would say that according to the entangled observer the "wavefunction has collapsed" whereas according to the unentangled observer, it hasn't.

Comment Re:Viruses? Oh dear... (Score 1) 148

We have a place in town that advertises on the radio to hurry in and buy your new computer from them because they are still selling Windows 7 but won't be able to do so for long. Given all the airtime they are buying, I have to assume their are a lot of people who don't want Windows 8. I wonder what makes Microsoft think they are going to want it on their Xbox.

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