Halc

Through spacetime, any geodesic traces a (locally) straight line, not curved at all. So a bullet going from me to a target follows a straight line, not a parabola. Similarly, the ball tossed in what appears to be a high arc to the basket also traces a straight line through bent (non-Euclidean) spacetime,. The apple doesn't fall up because spacetime isn't bent in a way that would allow that to be a straight line.

Indeed, and nobody is claiming they are, although your choice of the term 'particles' carries a bit of that connotation. If one quantum particle is sent through a double slit, we observe one point (where it is measured), something a wave sent through the slits will not do. The probability curve of where that measurement will be taken is what resembles an interference pattern. No wave exhibits quantized behavior like that. Sound (an example of an actual wave) passed through slits will be measured in all locations, not just one, and its intensity (yes, an interference pattern) will drop off as a function of distance from source to measurement. A photon or electron exhibits no similar behavior, being measured at full mass/energy at the measurement location and not measured at all at any other location. Sound (or any other real wave) ceases to propagate if you take away its medium. There is no medium for a photon or molecule passing through the slits, and yet they still arrive at the measurement location.

No, they're not. If measured in the right way, they share some properties with waves, but they also behave in ways that waves definitely do not. This doesn't follow. Just because I'm made up of cells doesn't imply that I am a cell.

I know the thought experiment well. You statement that the observer in the middle of the train boths observes the strikes simultaneously and not simultaneously cannot be correct. OK, you meant something else, but also wrong: There is no actual to it. Simultaneity of spatially separated events is frame dependent and there is no ordering that is more actual than another. The thought experiment classically suggests the strikes take place simultaneously in (and only in) the platform frame, which, as I said, is no more special than any other frame. Thus the guy on the train sees one strike before the other (because in the frame of the train, the one strike is actually before the other), and does not "experience lightning hit the front and back simulataneously" as you posted. Neither frame is 'correct'. Better worded is that according to Einstein, each observer is correct relative to the frame of reference in which he is respectively stationary.

This is a self-contradictory statement, and is thus wrong. He cannot both experience (observe) the two events simultaneously, and also one before the other.

By 'ends' I mean the bottom. If all the land and ice were spread evenly across the globe (like in waterworld), the bottom of the atmosphere would be something like 400m higher than current sea level, and pressure there would be no different than it is now. You get a lower figure with your method, but I was taking into account the current volume of ice which displaces atmosphere in addition to what the land does. I used 840 (reddit), more than 1/3 (more like 3/8), and used projected sea level rise from global warming charts to estimate ice volume. 400 is probably still a bit high. 360 maybe?

If you want a more accurate mass estimate, multiply the surface area by the pressure at an altitude of something like 400m, which is close to the average altitude where the atmosphere ends worldwide.

Not saying Earth masses less than the atmosphere. Earth is in freefall, hence has no weight. You can place Earth on top of me, in which case it would weigh about 900 Newtons, still considerably less than the atmosphere collective weight. A 20 digit number of Newtons is more weight than zero. On the other hand, weight is a force, no? Force is a vector, and adding all the force applied by the atmosphere pretty much (not completely) cancels itself out, leaving many fewer digits of actual net force (weight?) on Earth.

Venus orbits the same direction as all the other planets. But it spins on its own axis backwards, so it has one more day per year than its sidereal spin rate, as opposed to one less like all the other planets. Earth for instance experiences 365.25 days per year, but spins at a rate of about 366.25 times. Venus spins so slow that it goes around about once per Venus year, giving it just two days in its year.

First of all, weight is a force, measured in say Newtons. I did the pressure * area thing and got 5.1x10^19 Newtons. That's far heavier than Earth itself since Earth, unlike the atmosphere, is not resting on anything and is thus weightless. This is my first test post and it didn't take the html ¹⁹