Spacetime Continuum?

Question

I'm having difficulty understanding this concept. Please explain. Thanks.

Answer 1

In physics, spacetime is any mathematical model that combines space and time into a single construct called the space-time continuum.

Spacetime is usually interpreted with space being three-dimensional and time playing the role of the fourth dimension.
According to Euclidean space perception, the universe has three dimensions of space, and one dimension of time. By combining space and time into a single manifold, physicists have significantly simplified a large amount of physical theory, as well as described in a more uniform way the workings of the universe at both the supergalactic and subatomic levels.

Answer 2

Are you asking for a technical term from physics, Star Trek or the rock group?

In physics "spacetime" (usually without "continuum") denotes a mathematical description of physical space and physical time in which variables for both are being grouped into a single mathematical object that looks like a four dimensional vector (four-vector, 4-vector).

Theries of "spacetime" are very different from the description of space and time in Newtonian physics where time is assumed to be completely independent of space. Newton saw dynamics in space and time like we see a movie: at any time (e.g. constant, infinitely small time intervals dt) one can make a slice through space, take a snapshot like with a still camera and the total of all Newtonian dynamics is the "movie" that one gets by pasting all these still images together into a movie.

Because the movie "looks" the same independently of who in the audience is watching it, "time" is nothing else than nature's frame count in this analogy.

But this, it turns out, is not how the real world works. Instead, different movie-goers will see different movies, depending on how they are moving through the cinema, themselves! For some the movie plot will proceed slowly, for others it will be happening rapidly. Moreover, events of a twisted plot involving many different actors, as long as they are not causally related in the plot can happen in different order, depending on who is looking at them. And then there are causal events which happen in the same order, no matter who is watching them.

In special relativity, the leading and extremely well verified "spacetime" formalism, the mystery of this variable plot movie has been solved by grouping space variables and time variables together into one four-dimensional mathematical space. This space, however, is not like a flat sheet of paper. Instead, it has the global topology of a saddle, in which three directions go up and one goes down (or the other way around, depending which convention you use for the sign of time in the metric).

Now, I wish I could tell you how to visualize that... but I can't. For one thing I do not have the imagination needed, for another, mathematics does not allow to embed the resulting geometric object into a flat space of less than, I believe, five dimensions (or was that six?). The cool thing, though, is that we can see "spacetime" at work in relatively simple setting. If you still have an old stile tv or computer monitor with a CRT in it, the electrons that light up the screen are already slightly relativistic. And every time you get an x-ray, you are sitting in front of an even more relativistic electron gun. And once you start looking at the universe on astronomical timescales, a lot of things are so relativistic that any other explanation than "spacetime" does not even pass the laugh test.

Answer 3

For 'causality' to work (that is, "event A causes event B" or "event A happens before event B") the two events must be separated from each other in some manner. There are exactly two different ways in which events can be seperated; by space (distance) or by time (one happens 'before' or 'after' the other). When relativistic velocities are involved, it would be possible (under some circumstances) for an 'observer' to (for example) see person B shot by person A, --before-- person A pulled the trigger. Obviously this can't happen and it's just one more justification for the reality of the 'time dilation' which happens at relativistic speeds (and which so many people find so difficult to understand or believe). It seems that 'causality' is the fundamental guiding principle, and nature goes way out of her way (even to the extent of bending time ☺) to see to it that it's conserved. In essence, space and time are the same thing (similar to mass and energy being the same thing)

Doug

Answer 4

Space is described as a place where there is matter, where there is matter there is motion, where there is motion there is time. It becomes obvious that space and time can't be separated, except for one place, a black hole; here neither space nor time exists. Time can, and is, slowed at speeds near that of light because the mass of anything travelling at such a speed can approach the density of a black hole, but it can never get to that point, so some movement can take place in this object, therefore time and space still exist indside the object.

Answer 5

They were a great band around the Bay Area of San Franscisco in the late Sixties, early Seventies. Clarence Parker, their lead guitarist, was a genius, but he died young of too much ice cream in his Jack Daniels.

Answer 6

Its about a ladybird that flew soo high that it reched into space and when it looked down upon the heavens it realised that the world stopped spinning and time stopped. He felt soo lonely and cold drifting off into the darkness of space. It wondered why the world had stopped spinning and thought.........

Il let you another day, im too tired

Answer 7

sometimes when i cant find my socks and i accuse my wife of moving them, she tells me they must have fell thro a tear i the space time continuum, i think she is probably right as it always seems to happen.

Answer 8

i could, but it would involve diagrams and flowcharts! and you saying "oh my god" constantly!

you should have pais ttention in time lord school

how do you expect to pilot your own Tardis ?

Answer 9

You and hundreds of others. would not worry about not getting it at all.

Answer 10

if it is disrupted it can cause an alternate reality