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We are already travelling close to the speed of light. The clocks seem to work ok.Just as valid to say we are already moving at speeds exceeding the speed of light , account taken of expansion?
This is all initiated by an initial force generated at the time of the big bang.I have heard that this was not an "explosion".Why is this said and how do we know it is the case?
, I don't think that anything can get hotter than the big bang (otherwise there would be a flow of heat from colder to warmer). But I don't know how hot that was supposed to have been, and perhaps was "infinite"?
OK so are we better just (re)starting from the position that a vacuum is not only impractical to create but that it is a misnomer and that we can only really talk about relative densities of whatever we are considering?Quote from: OPIs "Space" distinct from "nothingness"? (and the Vacuum)My attempt:
A vacuum is when you have removed all the baryonic matter from a volume of space.
- You have to work very hard to ge a "good" vacuum, as atoms are always boiling off the container walls and seals.
If you really want nothing, you would need to remove light (not entirely possible above absolute zero), neutrinos (not possible with any shielding we can imagine), and Dark Matter (we don't even know what it is, let alone imagine a way to keep it out).
Could you give me an example?
That all depends on one's definition of 'object'. The word seems to be an abstract one with no physical meaning. It simply means this collection of <whatever> being considered/treated as a unitProbably how I was using it ..It seems like a "one size fits all" description. A Field might also be an object , I suppose(and everything is part of the Field(s) isn't it?
Anyone who remembers "The Fly" will recall the problems of reassembling atoms in their original order. Indeed the fact that a double slit transfer redistributes stuff into a transform of the slit convoluted with the incident beam, suggests that the probability of recombination in a recpognisable order is even less than Eddington implied. But that classic film ignored the fundamental conservation of matter - the fly could not be more massive than the original, nor could Bart Simpson, in the famous spoof remake, get any smaller. So no long finger, unless some orther bit is sacrificed..
Eddington pointed out about 100 years ago that if a student of physics fell through an intact floor and rematerialised in the room below, he would not consider it a miracle but merely one of the less probable solutions to a multivariable equation.Is there a (exponentially remote) chance that the student rematerializes slightly lacking in physical integrity ?
Alas, this obvious and profound observation seems not to have reached the elementary school syllabus yet, though it is plain that the regular contributors here understand it. What baffles me is why those who don't, frequently accuse us of sharing their delusions.
Can you even give an example of something that exists that doesn't have mass/energy? Even space-time contains mass/energy in the form of vacuum fluctuations.Is that just because (or connected to the fact that) any measurement of mass/energy is relative to a reference frame and all reference frames' location are uncertain in the real world?
Ironic that there should be spam in a link about healthy eating...Hope we are not being corny here.
I said it would move to a lower orbit because it would be colliding with all that mass, which might slow it down and cause it to fall.Thanks. So ,if an object moving in space was to eject some of its more massive components in a symmetrical (and instantaneous) way so as not to disturb its direction of travel it would not speed up as a consequence ?
As a nonsense thought experiment, (nonsense because the premise breaks all conservation laws), you're saying that suddenly there is this 2xEarth where Earth was, moving for the moment in the same trajectory. For the most part, this is equivalent to dropping a large and small rock from the tower of Pisa. They still fall at the same rate since on the grand scheme of things, they're both pebbles, as the Earth is a pebble in relation to the sun.
If you put something actually big where Earth is (like another star rivaling the sun), then the orbit would change as the object is large enough to significantly pull the sun away from where it would otherwise be. The orbital radius would drop. Likewise, if I dropped a moon mass from the Pisa tower, it would get to the ground in a bit less time than would the rocks, not because its acceleration is higher, but because the moon is massive enough to pull the Earth up to meet it partway.
More likely, the meteors will come from all directions and add pretty much no net momentum to Earth, in which case it will drop to a lower orbit since a larger mass with the same momentum will move slower, and slowing makes an orbital thing drop to a lower orbit.Would that be a good science fiction idea (to go along with warp drive etc)?