Yourself

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  1. It's actually closer to Texas and Louisiana than it is to Florida.
  2. Yourself

    Is reality a simulation?

    And in the universe where that CPU command sequence is executing is time no longer privileged and irreversible? In that case how would such a CPU order and execute commands sequentially? The fact that there's no "rational" reason for it seems to me to indicate that it's completely natural. The universe need not be rational. And if the universe were a simulation, what is it simulating?
  3. Indeed, if I remember my undergrad classes well enough it turns out that pointy objects actually experience higher heating loads than blunt bodies because there's more heat transfer to the vehicle from the air. Something about oblique shocks not doing as much to slow down the flow in the vicinity of the body (that and the shock is attached to the body, so the very hot fast moving air is right next to it).
  4. Yourself

    Gravity versus atmospheric pressure

    Technically atmospheric pressure does the opposite, it lifts you. After all, that's just the buoyant force and it's directly proportional to the density of the atmosphere. For example, on earth at sea level the presence of the atmosphere makes you about 0.1% lighter than you would be in a vacuum. All of this is because the air at your feet has an ever-so-slightly higher pressure than the air at your head, so the net effect over your body is an upward force. Of course it's also possible to get the effect where the atmosphere holds you down. That's how suction cups work.
  5. Yourself

    Do we live in a 4D world?

    I'm no physicist, but what I do know leads me to believe that this isn't accurate. Firstly, it's both time and space that warp, not merely space, so that's 4 dimensions to account for. Also even though it's warped that doesn't necessarily indicate that the 4D "surface" that describes our universe is necessarily the surface of some 5D shape. If I remember my differential geometry right that would be called an embedding, which isn't necessary to describe our universe. And, in fact, there's certain things about an embedding of a surface in a higher dimensional space that would be outright impossible for use to measure from within that space. That means that presuming that our universe is embedded within some higher dimensional space postulates certain properties which we cannot possibly observe, so I'd be reluctant to make the claim that it's true. I'd trust more for someone like @K^2 to comment further since this seems more up his alley than mine.
  6. Yourself

    Please improve Time warp

    I figured that had more to do with being able to keep up with the generation of planetary geometry.
  7. Yourself

    Orbital Mechanics Visual "Hack"?

    Even simpler, imagine a parabolic orbit, that encloses essentially an infinite area, but it takes a finite amount of ΔV to change it to a circular orbit, which has a finite area.
  8. Well, humans don't develop in isolation. DNA is mostly just a starting point, from there every interaction with the environment (which means every moment of your existence) influences what you become. To drive this point home in a rather not subtle way: one identical twin could lose a limb in a tragic and amazingly unexpected cake decorating accident. The loss of that arm is clearly not defined by that twin's DNA, but it will certainly become part of their identity then on. Of course nothing so drastic is required to establish a difference between identical individuals. DNA doesn't work by itself, it needs a whole bunch of machinery and environmental support to actually develop a multi-cellular organism and all sorts of little differences can get amplified over time.
  9. Yourself

    Rotating bodies in microgravity

    The rotation is only stable around 2 of the principal axes if each of the principal moments is distinct (the axes with the minimum and maximum moments of inertia will be stable, while the one with the intermediate moment will not be). This is described by the tennis racket theorem. The rotation of the book at the beginning of the video demonstrates this. The first two rotations shown are about the stable axes, while the third shown is the unstable one (since the book tumbles over a half turn every so often.
  10. Is there a way to invert axes on the indicator? As it is right now the pitch alignment is reversed from the yaw alignment, which actually makes it extremely difficult for me to control the attitude alignment because I have to do the opposite of what I think, but only in the pitch axis. This is also something that aggravates me with KSP's stock control scheme, since the translation controls are reversed in up/down from how they work in left/right (in one axis, they accelerate towards the direction you're pressing, in the other it accelerates opposite the direction you're pressing).
  11. Yourself

    Physics Question

    The shell theorem only applies to spherical shells of uniform mass, not rings. The ring will feel a gravitational force due to the central body if it's not perfectly centered. The shell theorem does allow us to treat the central body as a point mass (under the usual assumptions). See here for why this is unstable: http://larryniven.net/physics/img13.shtml
  12. Yourself

    Why light speed wouldn't matter

    My mistake. You'd mentioned the life support of the ship in regards to the travel time, but the life support travels with the ship, so the travel time from the perspective of the ship is all that would matter in that case. That's why I assumed you were talking about the ship's proper time rather than an outside observer's.
  13. Yourself

    Why light speed wouldn't matter

    Fortunately it wouldn't be 4 years from the perspective of the ship itself. From the point of view of a ship travelling at c, it would arrive instantaneously no matter where it was going. It'd take 4 years from the ship's perspective if it were travelling at ~70% c.
  14. How else would you expect it to work? If you don't move at all, you fall down and hit the planet. If you move fast enough you still fall down, but miss the planet. The faster you go, the farther you travel in the time it takes gravity to pull you down, so you end up reaching higher altitudes the faster you go.
  15. Yourself

    Nuclear Winter and Global Warming?

    Can we get them over the nuclear fear too? It just seems like nuclear energy has so much potential. Not really as a renewable, but we're going to run out of oil eventually and I'd like us to keep our options open when it comes to energy production until we get settled with renewables. I just don't have the confidence that fossil fuels will successfully bridge that gap. Also there's a nuclear heated lake nearby and the warm water extends the season for water-based leisure activities quite significantly. I quite like that. It's also a wildlife refuge because parts of the lake never freeze.