The EggLog

Is Space Quantised? (Part 1) | Is Space Quantised? (Part 2)

I have been reading a lot about this kind of physics recently; my current reading material is all about the string theory (a theory that is currently being researched and has not been universally agreed upon). What I think I have discerned so far is that space isn’t necessarily quantised below the Planck length, but can conventionally be thought of as not existing. According to Brian Greene, the definition of “existence” does not include the properties of the universe below Planck length. Unfortuantely, I can’t remember exactly why, and I don’t have the book to hand.

The physics of the universe below the Planck length is impossible for physicists to cope with as spacetime is constanly being warped and rewarped at this level: quantum foam. Quantum foam arises from the theory of quantum mechanics and is the divide between this theory and general relativity, which requires that spacetime is smooth at every level. The string theory bring these two theories together in such a way that they no longer clash like this, but that is a different story altogether.

If anyone anywhere has any help whatsoever, I would be very very grateful.

 Is Space Quantised? (Part 1)

 I’ve just read a book by John Gribbin called In Search of the Edge of Time about things like black holes and the fate of the universe et cetera, and came across (in chapter 8) the “Planck length“. This is the shortest distance at which anything is meaningful. John Gribbin describes it as quantised space. There is also such a phenomenon as the “Planck time“, the shortest amount of time at which anything is meaningful. John Gribbin also describes this as quantised time. As for my aforementioned “spixels”, these could still exist, but if they do, I’m sure they’d have already been discovered.

Is Space Quantised? (Part 3)

I recently had a “lying on my bed staring at the ceiling with a book lying on my chest, deep in thought” session and began to wonder: is there a limit to how small things are? What I mean is, once you are down to a certain level, is it impossible to get lower? The level I’m talking about is way below the size of quarks, neutrinos etc. I’m talking 10^-50 metres or something like that. This would surely make singularities more feasible (at least to the commonsense-based human mind). Instead of being an infinitely small piece of matter, therefore being infinitely dense, could the singularity exist in a single “unit” of space? The image I’m trying to conjure up in your mind is a sort of “pixel” of space. I haven’t thought extensively about this, but I can’t think of anything disproving it. Perhaps each “pixel” can only be either filled or not, like a binary digit. Perhaps these pixels could move, maybe helping to explain gravitational force. If you have a thought, either to back this up, or to put it down, then I really encourage you to comment. Meanwhile, I will be working on it on my own.

Is Space Quantised? (Part 2) | Is Space Quantised? (Part 3)