Wednesday, 11 April 2012

Questions of a Universal Sort

I feel like a preschooler who understands just enough to understand that they don't really understand much. Or like a fish in a glass bowl that can see just enough to know that something else is out there but can never figure out what.

Convention says there are four dimensions - length, width, height, and time. But why is time such an odd-man out? It seems strange to talk about three different spatial dimensions but only one of time. What if time also travels sideways and up and down? Then there would be six dimensions. And what if we take into account the imaginary plane with all six of these dimensions, like we do in electronics? The square root of negative one isn't just hypothetical; it's actually used in practical calculations. So we could hypothetically have twelve different dimensions - or would that count as just seven?

Superstring theory counts ten dimensions and M-theory counts up eleven, one of which is called supergravity. Bosonic string theory goes all the way up to twenty-six. So are the physicists who work on these theories discovering something or making something up? Are they inventing the math to express it, or discovering it?

However many dimensions exist, spacetime has been collapsed into one coherent continuum. Do other continuums exist? And does either space or time supersede the other? Are the non-conventional dimensions a part of spacetime? How do they relate? Can we exist within time while time itself exists within an eternal moment? Is time just a point of view? I almost think it must be, because it's nonsense to say that time "started" to exist. And by the way, if whatever is outside of time is infinite, then where and when is time? Is there such as thing as "nowhere, nowhen"?

Can we learn to cross all the dimensions? We can cross three of them pretty well already, but are stuck in a one-way current of the fourth. Quantum entanglement seems to have found a way to rise above location and time, but personally I'd rather not have my photons split in two in order to become transdimensional, however incredible such a state might be. At least, I'd rather not until I'm quite sure that splitting one's own photons is perfectly safe. But if there is such a thing as a transdimensional being... what sort of names might we already be calling them? And to what dimensions are they subject?

If the universe is expanding, what is it expanding into? If "nothing" is a lack of "anything" and describes most of our universe, how can this nothingness expand? Is there a nothing-squared that exists beyond the furthest reaches of nothing? What is nothing like? How can we even talk about the existence of nothing? Can nothing truly exist on its own without the comparison of something? The matter of the universe can't be just expanding into the same nothingness that already exists (or that doesn't exist, as the case may be), because in the infinite nothingness of an edgeless universe there is no such thing as location. So at some point there must be something less than nothing, because the only other option is to keep adding dimensions infinitely.

Are there parallel universes? How many? Do these universes cluster like galaxies? Do the clusters cluster? And is there a whole other level of these cluster clusters that never clusters or interacts with us in any form whatsoever beyond being under the control of the same God? How many universes exist? As Chris Anderson says, all we know is that the answer is somewhere between zero and infinity.

And come on, really - if existence is so huge and so complex, how could we ever believe that it all centres around us? How many other races and forms of life exist? What rules apply to them? Do they know about us?

Isn't it ironic that what we call a black hole is actually the furthest thing from a hole that we can imagine? A black hole is actually the most dense thing that exists - unless we assume that the entire universe was at one point a singularity. And time slows down after the event horizon? How can time ever cease to be anything but one second per second? And can a second ever truly pass?

If, to cross the room and touch the wall, I first have to cross half the room, and then half the distance left, and then half of that and half of that, I will never ever reach the end of the room and touch the wall. But I can cross the room and touch the wall.

If, to come home from work I must first work half a shift, then half of what's left, then half of that and half of that, then my shift will never be over and I will never leave. But my shift does finish and I come home from work.

So there must be a smallest minimum unit of spacetime, beyond which nothing can get smaller, or else everything would be in flux and though everything could be approached, nothing would ever be reached. A smallest unit, though - really? Instead of existing in a fluid, continuous way like we've always believed, we're progressing in a choppy, instantaneously changing sort of way? Like an animation? And if we look close enough, we'll pixelate?

Some physicists say yes, and that this pixelation is evidence that the universe isn't real, but a projection. That we're like Sims in a computer program or a greater entity's dream. That we only think we're sentient, whatever that means. That The Matrix and Inception aren't really all that crazy. But what would a real universe look like? Would it continue to get smaller for all of eternity? Plato would say that the real universe is where we'd find the forms.

It's mind-boggling! It makes my brain do somersaults. In glee. There is so much to try to understand, and such a pitiful hope that I will ever succeed (by the standard human measurement of "ever"), and yet it sure is fun to try!

"Now my own suspicion is that the Universe is not only queerer than we suppose, but queerer than we can suppose." J. B. S. Haldane


Aimee said...

No wonder your confused!

Entanglement is not all about photons splitting in two. Entanglement was described by Einstein as "spooky action at a distance", so yes, collapsing the wavefunction and observing the state of one entangled object will instantaneously determine the state of the other, but I feel this doesn't fit well with your multiple dimensions argument. Dare I ask, how many photons are you really made out of? I thought people made of light were reserved for science fiction!

Why is three spatial dimensions plus time strange? Say, if I throw a ball, at one instant, I can determine all forces acting on it. But it's really its trajectory, multiple units of time later, where this ball will hit the ground. Physics without time is bland and static. We can easily look at time propagating backwards. Time reversal is woven into the fundamental Maxwell's equations of electromagnetic fields. Think of time as a vector, pointing in a direction, rather than a spatial coordinate.

I thought the title of "black hole" was very fitting. It's called black because light can't escape beyond its event horizon.

Your definition of pixelation = quantization. At this level, interactions are governed by the principles of quantum mechanics! Yay!

You made the complexity of the earth seem bewildering. Yes indeed, the construction of the universe is excruciatingly complex and parts indeed seem outlandish and hard to grasp. But once you get over that, the complexity is beautiful and inspiring. Dive in! Contort your brain (correctly)! I dare ya.

Carla said...

You see how dangerous it would be to split my photons? First I would have to transmogrify and THEN split! Sounds scary to me.

I'm afraid I don't understand your explanation of time as a vector, but I don't find it odd that time is counted as a dimension. I find it odd that time is only one dimension, instead of three.

Aimee said...

I prefer to leave transmogrifying to Calvin and Hobbes. They have mastered that cardboard box like no other.

Yeah, that was more of a musing on life without time evolution. Still snapshots. Physicists who study general and special relativity describe a spacetime coordinate with a 4-vector - three spatial and one time dimension. Since the speed of light is not infinite (it takes a finite amount time for a photon, say, from my flashlight to travel to the moon), if I was on the moon to detect that photon at a certain time, I can rule out distances away where this photon could NOT have originated. Thus, we care about the time part of a spacetime coordinate.

Beautifully built through physics is a time-reversal symmetry. Maxwell's equations for electromagnetic fields possesses such symmetry. Don't ask me why time only appears to move forward.

Aimee said...

And this is why time doesn't have three spatial coordinates:

Imagine yourself as a three-dimensional coordinate system. If you move to the left, time would progress at a different speed than if you went to the right. Would time for a tall person be slower than for someone short? That could explain the tall, dense stereotype... No, time moves forward (if we're all standing still) at the same pace. Time dilation only comes into effect if you're moving, and it's only really noticeable if you're moving near the speed of light...

I strongly dislike special and general relativity. I am going to stop there.

art said...

The universe is complex and we know so very little about it. I saw this physics article that talks about multidimensional time. I also question if it is really correct to use a three dimensional xyz reference system when you are talking about space coordinates as space is curved.

I know what you meant when you made your comment about the black hole. From a telescope on earth perspective, it appears there is a hole in the universe - but in reality, it is the opposite of a hole.

Aimee said...

Of course! Curvilinear coordinates ftw! I took that as a given...

Ah, the good ol' higher dimension trick; everything is always simpler in a higher dimension. We do that all the time in quantum information as a calculation technique.

Take note, this use of "multiple time dimensions" should not be confused with the thermodynamic arrow of time.

(These hyperlinks are fun!)