Yeah, because this is untimely, facturally inaccurate, five years old, and equivalent to a story about the sun being made of freshly chopped artichoke hearts? Meanwhile things like this and this are timely wellsprings of useful information?

And care to respond to the people mocking your "busy weekend" excuse, given that your weekend appears to be five days long and your "the main reason it's late" post which gives an entirely different reason for the delay?

No, from both perspectives it seems like the time of the other has slowed down, including Earth from the perspective of the ship.

This is not only incorrect, but impossible. If my time is speeding up and I'm looking at your watch, it's going to appear to be slowing down, and vice versa. Two parties both slowing down will appear indistinguishable from either party, rendering the concept of time dilation pointless.

The rest of what you wrote is what I wrote, just phrased differently: that from the perspective of the people on the ship, the 4,3 light year journey only takes 70 days. They are not capped in their rate of travel by some cosmic absolute "speed limit". Only to a third party to which they are moving relative will their velocity appear to be unable to reach or exceed c.

Numerous pages, including this one from NASA, say that from an outside perspective it takes an infinite length of time for an object to cross the event horizon. Here's an "Ask a Physicist" column about black holes that says that time distortion reaches infinity at the event horizon. The Wikipedia article on event horizons says the same thing.

From our perspective, nothing ever passes the event horizon and thus the information is never lost.

They sort of do, but they're so distorted from our perspective as to be unrecognizable. Matter entering a black hole appears progressively more stretched out across its event horizon and doppler shifted.

No, from an outside perspective it's never inside the event horizon. Only from the perspective of the matter entering the black hole does it cross. Saying "by then it's well within the event horizon" is simply not accurate from an outside perspective. No data collected from Earth will ever correspond to a reality in which the object has passed the event horizon.

Which is why there's no information paradox: the information is never in an unreachable state from any perspective.

Another one that I see a lot of people having trouble with: that of there being a universal speed limit. I'm surprised at how many people think this means there's a speed limit from all perspectives.

If we launch some incredible 100fold-staged antimatter spacecraft capable of reaching 0.999c toward Alpha Centauri 4,3 light years away, from the perspective of people on Earth, it'll never reach or exceed c and will take a touch over 4,3 years to get there. But from the perspective of people onboard the spacecraft, they're reaching their destination in only 70 days. From our perspective, their time slows down 22,4-fold; from theirs, Earth time has speed up. We see their velocity as capped off at c; to them, it's as if they can just keep accelerating without limit.

Now, it's not exactly like "going really fast"; everything around them seems pinched toward the forward direction and shifted to blue, like this - the same situation as where we see light emitted from particles moving at relativistic speeds relative to us (such as a black hole's event horizon) doppler shifted and distorted. If the occupants of our spacecraft go fast enough, even the cosmic microwave background will be shifted into the visible spectrum. ;)

AFAIK: black holes are not sphere shaped, from our perspective - they're shell shaped. From our perspective as an outside observer, the singularity does not exist. From our perspective, time has slowed down on each particle moving into it from a near stop; they never actually pass the event horizon. Even the mass of the parent star that formed the black hole never reaches the event horizon as it is defined at the point in time that the star is collapsing, even though the event horizon may in time swell to a size that extends beyond where a collapsing particle was. Any light emitted from a doomed collapsing particle which manages ultimately escapes will do so on an escape trajectory that will always appear to come from outside the event horizon, no matter how much the black hole grew while it was in transit. From our external perspective, the particle never entered; the area beyond the event horizon is not part of spacetime to us. Now, as for an entity moving into the black hole, the perspective is different - the "hole" is quite well defined spacetime and they can enter just fine. But from our perspective, that entity never entered - it just slowed down to a virtual stop, stretched out across the event horizon.

Again, AFAIK, from my reading of the answer to the Hawking information paradox.

We love metrics that are continuous. We perceive the world with a Euclidean metric. And we generally don't have trouble understanding metrics distorted from the euclidean, such as the taxicab metric. Even the concept of a metric with points that bend space, simple gravitational distortion, is something we can usually grasp well after we get used to the concept. But people have trouble picturing a metric where space is warped by gravity so much that there exist regions where our euclidean mind insists must be there but actually aren't.

Unfortunately, when it comes to rockets, a couple percent difference in performance means a huge difference in the first stage.

The Russians make quite good early-stages for their rockets - but they've long had trouble with the upper stages. The N1 being the glaring exception, even the first stage was big trouble... they just couldn't handle the necessary level of QA for such a complex design to work, at least not on the budget they were given.

It also made them a lot more sensitive to the manufacturer, however. Underfunding a project almost certainly led it to being a disaster (the N1 rocket being a classic example). They generally were willing to sacrifice performance for ease of production and quantity - it was very much a widespread phenomenon.

A friend of mine once served as a translator for the military during one of the late mutual nuclear disarmament treaties (don't remember which one). She described them as pretty much a scam, in that both sides wanted to get rid of their old weapons anyway and it gave them an excuse to put funds toward development of new, treaty-compliant weapons. But anyway, they were allowed to inspect any area small enough to contain a "treaty limited item". To figure out whether they could inspect it, the teams were equipped with sophisticated laser measuring devices - if it determined that the space was large enough, they could inspect it. The Russians were really impressed with it. They sent their teams over with... a stick. If the stick fit, they could inspect it. ;)

Another example she mentioned was driving licenses. You know, if you get stopped in the US, they take your license, run your number through their computer, it connects to remote databases, they look up past offenses, they register a new one, etc, and give you your license back. In the USSR it was much simpler: the officer took your license and punched a hole in it. If you had too many holes, they kept it. ;)

I know it's such a stereotype that the Russians preferred low tech solutions vs. the US, but she said that the stereotype was totally well deserved. ;) She also found that they weren't as inclined to get a joke. She and some the guys on her team found it rather sad that these incredible weapons delivery systems were just being destroyed, literally crushed - devices that could deliver a payload anywhere on Earth with precision. So for fun they did some calculations for what they would have to do to reengineer one such that you could load up frozen pizzas onto racks and have them cook on reentry then parachute to the surface - they figured that given the reengineering and operations costs, a person ordering a very large order of pizza could get them for about $20 per pizza, delivered by decommissioned ICBM. They wrote up a formal "proposal" with all the calculations and budgetting and had her talk with what she described as the Soviet equivalent of a colonel about their "Intercontinental Pizza Delivery System". She said he stared at her like she was mad. ;) Totally didn't get the concept that it was a joke and thought that the US team was honestly proposing a private pizza-delivery-by-ICBM venture.

13% of Proton launches (46 of 355) have ended in failure - it's not a very impressive record.

Because if there's one thing Russia is famous for, it's QA ;)

Absolutely true. Soyuz too has had tons of third stage failures. It's something that just keeps biting them.

I think it's pretty amazing that spacecraft can survive at all out there, given the sort of particles flying around - individual cosmic rays with the energy of fast-pitch baseballs. Thankfully, particles with such high energy have tiny cross sections (they prefer to move through matter rather than interact with it), and when they do hit something and create a shower of particles, most of the progeny is likewise super-high energy and will most likely just move through whatever it's in.

It's more interesting when they strike the atmosphere - each collision creates a new shower of other high energy particles, more and more, spreading out the energy as they descend. In the end, detectors on the surface over an area of dozens of square kilometers simultaneously pick up different pieces of the same cascade kicked off by a single cosmic ray collision.

No, fines for violating export laws.

Being slapped with massive fines is usually pretty good motivation for a company. And given that the US spends nearly half of the world's total military spending, and the EU a good chunk of the rest, simply "hopping overseas" and choosing to serve other markets isn't exactly the smartest of plans, financially.

It's idiodic for a company to wilfully risk sales of hundreds of thousands of units per year to NATO to sell a couple hundred units to Russia. Russia's economy is barely bigger than Canada's. And less than 80% the size of Brazil's.

You could start by reading more than the first paragraph.

1) They don't have "zero" capability, but they have way too little - only a few hundred modern imagers.

2) They have tried to buy them off ebay before. And it led to arrests. It's illegal to export military-grade night vision equipment without a license, and apparently sites like ebay are well monitored for potential violations.