Frustrated Over Tonight's Morgan Freeman Show

BadBrain

I've just seen tonight's episode of "Through the Wormhole with Morgan Freeman", which dealt with empty space and the concept of nothingness at the level of quantum mechanics. Although it death with many interesting ideas and observations it overlooked the most obvious fact about "empty" space, that being the fact that it consists of the dimensions of space-time, which are bent by the gravitation permeating the universe. While we've observed gravitation warping space-time in the proximity of masses, and proportionally thereto, we must recognize that what is being warped are not the masses themselves, but the very dimensions of space-time.

So, forget that "empty" space is full of photons, particles, molecules, and even gravitons. "Empty" space is full of dimensions, expanding faster than the speed of light, and subject to warping (and twisting) by gravitation.

I guess what I'm really saying s that space itself is a thing, a tangible, malleable object. Therefore there is nowhere in the universe where nothingness exists.

Drakkith

I'm not too sure about this.

That depends on what you define as nothingness.

BadBrain

Look, if spaciotemporal dimensions are subject to gravitational warping, then space-time itself is a malleable object.

Necessarily!

phinds

Although I don't buy your argument at all, I do know that Through the Wormhole is often just trash.

Chronos

It's not really spacetime itself that is warped, it's the coordinate system we overlay on it.

TheTechNoir

Co-sign.


For the original poster: http://en.wikipedia.org/wiki/Geodesi..._relativity%29 Try reading this and relevant links. While that show is generally trash as phinds said, an episode about spacetime on a quantum scale need not talk about GR and you seem to have misconceptions about spacetime curvature as well.

Naty1

I happen to think that view makes sense...except I like 'spacetime' better.....and we have discussed/argued it in these forums before. "spacetime" also has dark energy and virtual particles and the Higgs field...so it is always something.
The contrary view:

So is our world what we observe...or to what we can ascribe characteristics....or something else?

I see this view as a bit to restrictive: for example, global particle states are only well-defined in a flat spacetime and inflationary spacetimes lead to particle production....and for deSitter expansion the particle horizon is constant in time while spacetime is accelerating.


So for me it is not so easy to dismiss 'spacetime' as 'something'.

BadBrain

I read the article you linked to.

For the purposes of this argument, it really doesn't matter if gravitation is a particle force or a property of matter. Spacetime is being bent in either case, which makes spacetime a malleable object.

And were spacetime truly the mere product of the electromagnetism/weakness/strength (and, according to string theory, gravitation) occupying it, then how does that explain the expansion of the universe's dimensions at a rate exceeding that of the expansion of the other stuff which it contains, the discovery of which fact won last year's Nobel Prize in Physics?

phinds

I don't know enough to refute your statement with facts, and you may well be correct, but I do recall that quite a few posts on this forum have insisted that space, as a part of spacetime, is not an "object", it is simply geometry, as odd as that may sound. The expansion of the universe is NOT a "stretching" of a "fabric" at all. Look up "metric expansion" for more details.

HallsofIvy

Essentially what you are telling us is that you do not know what 'dimension' means. Space "consists of dimensions" only in the sense that space consists of rational and irrational numbers, polynomials, and whatever other mathematical constructs we choose to use to try to understand physics.

BadBrain

No.

Those mathematical concepts are derived from nature, and, however imperfect those mathematical concepts may be at describing nature, they can only describe the nature from which they've been derived.

I'm way the hey not saying that the four dimensions so far discerned from our study of spacetime are the only dimensions that exist; indeed, the very existence of dark matter and dark energy implies the existence of dark space and dark time, i.e.,spaciotemporal dimensions yet undiscovered.

The dimensions of spacetime are not human constructs, but human abstractions derived from observations of nature.

phinds

AAAARRRRGGGGG !!!! Where do you GET such nonsense???

Nabeshin

This statement alone shows you know absolutely nothing about what dark matter or dark energy are. This is also completely irrelevant to the discussion of the nature of spacetime.

Drakkith

Please, stop making up words. Learn the correct ones instead.

No, a dimension has a specific definition that we have given it to describe something in a precise way. It is no more abstract than a meter or a second is. Whether our model of spacetime is an accurate description of it IS arguable, and it is very accurate to our knowledge. But not accurate enough, as we know several situations where it breaks down.

Naty1

This is one of those issues that has 'facts' on both sides.....I previously posted maybe 20 or so examples of 'why spacetime IS something"......and a majority as I recall still did not like the idea....

Seems to me that applies to TIME as well.....As an example, relativity tells us your view of space and my view of time morph into each other as our relative velocity changes...via the Lorentz transform......so how can either ever be 'nothing'??? [Of course there ARE answers.....]

BadBrain

I understand that, as I demonstrated by means of my subsequent posts #3 and #8 to this thread. Kindly interpret any use, on my part, of the term "space" with respect to GR, unless I indicate otherwise with great specificity (which would involve, foreseeably, the discussion of but a single dimension, most likely the dimension of time), as a misstatement on my part of my intended meaning of "spacetime".

And thanks for your support!