Is space curved?

[kjbunker817]

Is space curved or not? If yes, how? If no, how? I have heard many arguments for both sides. Looking for answers for the simple minded.

[Student_777]

I say neither if the thing about space going on forever is true because if space is infinent then it is neither round or straight, it has no shape i guess

[kjbunker817]

I say neither if the thing about space going on forever is true because if space is infinent then it is neither round or straight, it has no shape i guess

 

Never thought of it that way. But then does space have structure?

[YT2095]

some parts of space are more curved than others, it all depends on the mass of an object in that region of space, the more massive, the more space curves.

[mysolipsis]

i agree with the resourceful one, you can't like of space like a finite shape, which student does. think of it as infinite layers, and sheets of rubber in all directions, where the mass effects the way it flexes therefore curving it.

[swansont]

The statement that "space is curved" is a shorthand for saying that the coordinate system best used to describe it is non-Euclidian. e.g. the shortest distance between two points is no longer a straight line in Cartesian coordinates. It's not a comment about whether space is infinite in extent or not — that's a separate issue.

[Norman Albers]

This is the theoretic picture we are still coming to understand, and it is expressed in General Relativity. It comes down to differential calculus which is designed on the principles that: 1) speed-of-light is, locally, is always measured the same. I observe that this assumes physics is always the same, and if there are black holes I doubt this is so. 2)Isotropy; this is clear except in rotating systems. 3) The reduced Riemann curvature tensor [math]R_{ik}[/math] expressing the local changes. What is experienced in one frame will be measured with signal exchange according to the ratio of the metric factors of the two locales.

[Norman Albers]

GR gives possibilities of interpreting space-time based on minimal mathematic assumptions like vectors changing smoothly in their representation as they are moved around, and then too that the Lorentz form <1,-1,-1,-1> describes physics anywhere locally and everywhere "in the far" with respect to gravitational sources. Now look at a straw in a glass of water or light going into a lens, and we see changes of light-speed from what we call "optic index". Many theorists have written on interpreting the Scwarzschild metrics as the result of a scalar field of permittivity, and plugging this into the assumed geometry, we can see first why light follows the geodesics it does. Go a big step further and acknowledge that this vacuum physics is the actual substrate of matter, and we can see why mass follows the paths it does. I am trying to go them one better by tracing the whole metric phenomenon to the nature of particles themselves, and showing how this produces what was mathematically shown to be a reasonable geometry with which to represent what we need. I think it may be a poor assumption that physics does not change inside horizons; it seems to me there is fundamental change in the form of the vacuum fields and thus matter and energy are "collapsed". . . . . . . .Now get an E&M textbook that has a good section on dielectric theory, and you'll see the effect of a finite polarizability giving rise to a singular state of polarization.

[Farsight]

The world is just painted in light, Albers.

[Norman Albers]

STATES OF ENERGY . . . . . . . . . . .If you follow a light-ray through a piece of clear material whose optic density changes, what will you see?

[Norman Albers]

I always loved raisin-spice cake, dark with molasses. Someone, elsewhere, alluded to a spacetime "cake". We can agree that differerent observers slice differently according to their velocity frame of reference, so I told this person that it is not possible to uniquely define it. Relativity deals with differential changes from point to point. THIS IS IT'S GENIUS, AND IT'S LIMITATION, SURELY. Further, what is 'space' but the behavior of electromagnetic disturbance, and gravitational disturbance, and furthermore dark whatever describing our ignorance??? I propose a toast, To our ignorance!!