Science Forums 2

[Boerseun]

Sorry - been away for a bit, only caught up now...

Interesting comments, all. But I have one thing bugging me still, apart from the fact that I don't buy the "there is no time, only motion" bit (I can't see motion defined without time being in the equation).

The smaller we probe, things tend to get fuzzy. This is because of the limiting nature of the wavelength of light. So we switch to using light with a shorter wavelength to probe our sample. Eventually we end up using electron microscopes instead of light, so that we can see ever smaller things. And so on. And eventually we get to the Planck length, at which point the universe starts to "pixellate" like a .jpg file if you keep on enlarging it. And it's at this level where its said that we're living in a "block" universe, if I'm getting it right.

Quick analogy: If the best tool you have is a backyard microscope and you look to the surface of Mars, you'll see icecaps and surface streaks. But it'll be pretty fuzzy. Are you going to conclude that the surface of Mars is, indeed, fuzzy, because all the evidence point in that direction, or are you going to conclude that seeing as you can enlarge the picture (you have been doing so, proceeding from eyeball to binocular to telescope) and everytime you do so, it becomes more detailed and sharper, that Mars is not fuzzy, but you're simply lacking in equipment?

Same with the nature of matter. We infer the fuzziness starting at the Planck length, because we can't measure the time it takes for anything to happen to a precision greater than the time it takes a photon to travel the planck length - because we're using photons to measure it. We can't see the details on the surface of Mars to a precision greater than what our crappy backyard telescope would allow, because we're using our crappy backyard telescope. Using our crappy backyard telescope as the final yardstick, would deny the existence of all the surface features on Mars.

We are inferring properties to Nature based on the limitations of our tools. In my opinion, the fact that we can't measure shorter than Planck length says nothing about the properties of matter at smaller scale than the Planck length. It does, however, say a lot about the tools we're using. And inferring the 'blockiness' of Nature at the Planc scale, or the pixellation of time, is simply jumping to conclusions. But that's just me.