/sci/ - Science & Math

Tiem might actually be a field.

>>5006382

define reality first.

>>5006382
yep

http://en.wikipedia.org/wiki/Planck_length
http://en.wikipedia.org/wiki/Planck_time

No.

http://www.youtube.com/watch?v=EYPapE-3FRw

My god, that door is beautiful.

>>5006437
>>5006469
Not sure who to believe.

>>5006493
I would choose the zoology major who has her physics knowledge from wikipedia for sure!

>>5006556
>mfw

>>5006493
i didnt watch a fucking 10 min youTube vid, even if it is feynman
can i have a tl;dr please?

>>5006563
I'll watch it and tell you, there might be something interesting

>>5006563
tl;dr space is continuous rather than finitely divisible

also
>not knowing every Feynman video on youtube bu heart

>>5006556
fuck you ya pretentious cunt! planck time is a real thing! i didnt just fucking make it up!
and fuck you, i bet zoology is 10 times better than whatever fucking shit major you decided to take!
oh wait, you didnt, you're still in fucking highschool!
eat shit!

He only mentioned continuous space once and he didn't explain if it was real or not.

>>5006566
thanks hun
i'll be waiting

>>5006482
you can keep the door, but give me the girl.

>>5006568
no shit sherlock, i got that
but HOW and WHY
evidence??

>mfw I made that question some time ago

general consensus back then was that apparently if the space WAS discrete, guys at supercolliders would have noticed.

Planck length and Planck time are not inherently quantization of space and time. They are an interesting combination of physical units which result in units of length and time, but they are not a result of observation of any sort and what they do arise from does not really call them a quantization of space or time, just the smallest scales that matter to measurement. From what I can recall, this idea stems from the various string theories, but strings are objects that exist below these scales and so it is not really a hard quantization of space, just a limit on what scale measurable dynamics occur at. Even with this, it is not necessarily a correct picture as string theory is not exactly confirmed or even complete mathematically speaking at the current time.

>>5006568
>mfw my profs lessons are still funnier and more interesting than his
>>5006570
he basically says that if space was not continuous, he would know about it.
tl;dr: he doesn't give any explaination, I am disappoint

>>5006573
I didn't imply, that planck units are not real.
But they have nothing to do with OPs question and you would know that, if you knew at least some advanced physics instead of some wikipedia knowledge.
Eat shit, EK

Don get too caught up in what Feynman said briefly about space made up of a series of dots. Remember that he was objecting to the letter saying ¨reject this¨ without giving a substitute, and Feynman says that by noncontinuous space typically one means a discrete lattice of points with space between physically irrelevant.

This can be proved wrong by theory most easily, as it breaks a lot of well-established theories without helping anything new. Experiment follows directly from the well-established theory.

One issue, the first one I raise with having space be a lattice is that it violates the idea that there is no special direction on can face in space that would change an experiment (something akin to the Cosmological Principle), which violates Conservation of Angular Momentum (by breaking symmetry of angles in a circle) most prominently.

However, the notion of a lattice is only one interpretation of ¨non-continuous space¨ or ¨discrete space¨. (TBC)

>>5006693
so there still could be a "dense" lattice?
Just like [tex] \mathbb{Q}[/tex] is dense in [tex] \mathbb{R}[/tex], for example?

>>5006693 cont.

There is an actual scientific (or philosophomathematical) argument for certain types of noncontinuous space, however.

A central issue that I have read about is that if space were defined in continuous real numbers, the physical laws would have to be ¨computed¨ using arbitrary real numbers. As it turns out, a set of arbitrary real numbers can form a hypercomputer, by means of each real number being noncomputable, thus storing an endless instruction set.

There´s nothing in physics that says we cannot have a hypercomputer other than that every currently-known means of making a hypercomputer is banned by physics. So that is a precise issue that can be raised when somebody claims space is defined in a continuous set of real numbers. One could of course argue for a continuous set of rational or computable numbers, but that has no ¨measure¨. Again, nothing in physics says your reality cannot have measure, other than the fact that its not known how one would have reality without measure (though the physical consequences thereof are also not known).

So the answer is that the current theory has no bias as to whether or not the universe is measured as a continuous set of reals, or whether it is rationals (which in some sense *are* discrete). Current theory doesn´t care. However, if you are to pose this question, any answer one could give would be mathematically discomforting one way or another.

>>5006594
I don't see why. Even if they'd notice space wasn't discrete in sections of 10^(-300) meters for instance, we could always guess that space was discrete at a level of 10^(-3000) or 10^(-10^3000). There's infinitely higher numbers and if we go far enough we might get outside our ability to distinguish.

>>5006469
the related vids are a whole evenings worth of inspirational entertainment.