Delta1212

You do realize that the constant velocity of light means that if I see a beam of light shining away from me, I will measure it as moving at 186,000 miles per second. If I accelerate in the direction of the light so that I'm moving 100mph, I will measure the light moving 186,000 miles per second faster than me, and if I accelerate in the direction of the light until I'm moving at 185,000 miles per second, I will see the light moving 186,000 miles per second faster than me. That's what light's constant velocity means. There is no preferred frame through which it moves at 186,000 miles per second. It moves trough every frame at 186,000 miles per second relative to that frame.

For the acceleration to cause Doppler shift, the clocks would have to be moving relative to the observer during the acceleration phase. If it's a persistent effect, the ship would either be crushed or ripped apart by continuos acceleration given enough time. You would get some slight compression at the start equivalent to what you'd get in a gravitational field of equivalent strength, but it's not going to be enough of a difference to be measurable. You'd probably see more of a loss of synchronicity from relativistic effects if you picked one clock up and carried it across the room.

Well before we get to answering that question. Let's say the plane is parked on Earth. What's its speed?

I'll get to the last question if you bear with me for a bit: Yes, a person looking out the window would be able to tell if the plane was moving (with respect to the Earth) because they can see the Earth moving outside their window. If the plane and its passenger were the only things in the universe and all the passenger saw when looking out the window was blackness, would there be any way to tell if the plane was stationary or moving at a constant speed?

How would you be able to tell if it was moving?

It's impossible to have an unbendable, incompressible stick. It would require a material through which the speed of sound is faster than c.

All motion is relative to something else. What is the universe moving relative to?

Two points, while you didn't say that everything in the room is moving away, that is what we observe in the actual universe, at least everything that isn't close enough to be gravitationally bound. So yes, if stuff was just randomly moving about, using that as evidence for the universe expanding would be silly. That isn't what is happening though, and using an analogy that ignores what we actually observe isn't going to allow you to draw any conclusions (really no analogy should be used to draw conclusions, but a bad one is that much worse). Second, objects at the edge of the observable universe are all receding and objects significantly closer (though still far away) are receding. Unless you thing that the universe was expanding for 13 billion years and then suddenly stopped around the time the dinosaurs walked the Earth and we just haven't noticed because the light hasn't reached us yet, what you're proposing doesn't match what we see. Additionally, when we compare the rate of expansion over a given distance between the closer and farther objects, there is a discrepancy that implies that the rate of expansion in the past was actually slower and that the expansion is accelerating, not slowing down. Finally, setting aside the question of universal expansion for a moment, if you think the speed of light is related to the movement of the universe, I have to ask: What do you think the universe is moving with respect to?

If everything in the room is moving away from you with the furniture farthest from you moving away the fastest and this includes the walls, then the room is probably expanding.

But even in that case, once the target speed is reached, the Doppler shift should be non-existent unless they end up with different relative speeds.

You would be correct. Just because I'm moving when I climb into the back seat doesn't mean that the car isn't in park. Things move around within the universe. This is not the same thing as the universe itself moving (with respect to what?) nor is it the same thing as the metric expansion of space. As far as what that means: space is expanding. That is, the distance between objects is increasing even though those objects are not moving (this is only noticeable at very, very large distances as anything closer enough to be even in the same group of galaxies is close enough for gravity to overcome the expansion). The rate of this expansion is generally given as kilometers per seconds per megaparsec. To visualize what this means, imagine that you have a ruler that is a foot long. Every second, that ruler grows by one inch. You put it down in front of you and after one second, the end of the ruler is now one foot and one inch away. Now imagine that instead of one ruler, you placed 12 of these rulers end to end. Now, as each expands, it pushes the next one further away, so after one second, the end of the row of rulers is now 13 feet away instead of 12, an extra in for each ruler. So you can say that the end is receding from you at a rate of one inch per second per foot.

How can you observe Doppler shift from something that is stationary with respect to you?

I found a few references to it being accepted for publication by the Journal of the British Interplanetary Society last year, but I haven't been able to track down an actual publication date.

Link works for me.

The universe isn't moving. It's expanding, but that is quite different. Since the rate of expansion is given as distance per unit of time per unit of distance, it's not really comparable with a measure of speed.

Jeb has it marginally worse than Hillary with regard to political dynasties. Hillary's predecessor has become a lot more popular since leaving office, while Jeb would be the third Bush in five presidents, and neither was particularly popular, even if W's unpopularity has waned a bit. Incidentally, I don't think that it's just time, forgetfulness and being relatively innocuous that has improved (or whatever the equivalent for "made less hated" is) W's standing. By comparison with the modern GOP, W comes across as much more likeable. He probably did more actual damage, but you never got the sense that he was trying to harm the country, just that he was a collars all screw up that wasn't above lying to push an agenda or cover his ass. Today's GOP, on the other hand, seems like it would be willing, nay eager, to torch the whole country if they could do it in a way that would let them blame the Democrats. Put up against that W seems like a reasonable Republican.

Well, in this particular instance, I had the alarm set for 6:15 (the time I actually needed to be up by) and woke up at 5:30 (the time I was shooting for just for the sake of this topic). Unless my phone starts making noise 45 minutes before the alarm goes off, we can probably rule out clock noise for that. The more likely source of any error in this case is probably coincidence, since I didn't set anything or tell anyone that I wanted to get up at 5:30 and working off a sample size of one makes the result fairly susceptible to the quirks of random chance.

Just to toss in my own contribution science, what little good a single data point will do, but I decided to do a test on myself. Normally, I get up at 6:30, which is what my alarm is set to get me up by. I needed to get up a little earlier today anyway, so I set my alarm for 6:15 and decided to shoot for a bit extra for the sake of science and decided to try for 5:30 (unnecessarily early, but I wanted to be able to distinguish from the time I normally wake up). I went to bed thinking about waking up by 5:30. I woke up this morning and looked at the clock: 5:32. Obviously not a rigorous study, but there's the result of my one-off experiment.

Atomic and sub-atomic particles don't behave like billiard balls. The rules are different at that level.

Science has a lot of unanswered questions. If it didn't, there wouldn't be any scientists.

If you mean literally the first ancestor of humans, the first ever life form from which all other life is descended, the answer is that we don't really know. We have a lot of ideas about how various structures are formed and we have some evidence that it isn't particularly difficult for basic compounds necessary for life to arise as part of natural chemical reactions, but how exactly, and under what circumstances, the first forms of life came about is a subject that is still debated because we don't have enough information to answer the question definitively at this point. If you mean the first humanoid ancestors of humanity, that has slightly more detailed answers available.

It was already mentioned earlier, but maybe I can clarify. It's very common for people to wake up during sleep and then almost immediately fall back asleep. When they finally wake up, they probably won't even remember that they woke up. If something happens during that brief waking period, it draws enough attention to keep you from falling back asleep. If nothing had happened, you'd have fallen back asleep and forgotten you even woke up. It's not that you have a tendency to wake up right before something happens. It's that you have a tendency to wake up, and if something happens, that wakefulness is more likely to stick. If it doesn't stick, you probably won't even remember you woke up, leaving only (or mostly) those times when something happened to stick in your memory.

1. Don't know enough about the specifics to comment on that particular case. 2. Birds. Birds are descended from dinosaurs. I find it easiest to see the resemblance when looking at baby geese, myself, but it applies to birds in general. 3. Humans are apes. We're descended from the same animal as chimpanzees. That animal was descended from the same animal as gorillas and orangutans, which was descended from the same animal as monkeys, which was descended from the same animal as rats, goats, elephants and whales, which was descended from the same animal dinosaurs, crocodiles and frogs, which was descended from the same animal as sharks, octopuses and jellyfish which was descended from the same organism as trees, E. Coli and mushrooms. Other than picking out chimps first as our closest living relatives, there isn't anything particularly special about the particular forms I life I picked out, other than that they were less related to use than the previous set I mentioned and more related than the next, by the way. The point was simply that the first back in time you go, the more things you find that are descended from the same living thing and, if you go back far enough, all life on Earth is related.

Imagine you have a nice sized pool in the back yard. Now you take an empty gallon milk-carton, fill it with water from the pool, carry it around to the front and dump it out on the street. That doesn't seem like to much effort right? Now imagine trying to empty the entire pool into the street by hand, just using that 1 gallon carton. The difference between moving a fairly large asteroid and moving a planet is approximately the same as the difference between moving a gallon of water and a swimming pool of water. And in the case of the planet, the vast majority of the mass you're moving is on the interior which is completely useless to you. If you hollow out an asteroid, you can make use of the whole thing so you aren't carrying around extra mass. Hauling a planet just means you have to work that much harder to carry around a completely unlivable landscape surrounding your artificial habitats instead of solely carting around the useful living space.

I suppose Indiana Jones could have avoided that sprint through the temple if he'd just thought to divert the boulder around him by blowing on it.