How Is Motion Even Possible?

[CycloWizard]

Originally posted by: gabriel87120
Take it from me, I am a physicist. The guy I am quoting stated the answer.

If you really were a physicist, I would have to believe that you would know that your statement below is mathematically incorrect, since infinity divided by itself is not equal to one.

So as you move, finite amounts of molecules in your body move over finite amounts of space. Incorrectly analyzed mathematically: infinite points in your body move over infinite amounts of points in space, so it's infinity over infinity. And we know anything divided by itself equals one... one stupid argument.

The real reason is that points are mathematical abstractions, not reality. In physical modeling, we attempt to achieve a one-to-one mapping of particles using vector or energy mappings. The math behind how this is actually achieved is very well documented and has been developed over the past 500 years (even longer if you consider the seminal works of Aristotle).

 

[TheArabian]

Originally posted by: jakalsucks
Read up on Zeno's paradox, and please don't post while high.

:thumbsup:

 

[morkus64]

reminds me of good ol' Riemann...

 

[DrPizza]

Originally posted by: gabriel87120

Take it from me, I am a physicist. The guy I am quoting stated the answer.

Points are not physical, you do not "move along a series of infinite points" because technically they aren't there. You do however move along a series of finite planck lengths during a finite amount time.

The measurements of the universe are actually finite in its basic structure. Think of a knitted sweater, the thread being the universe's material, and the holes being the nothingness having diameter equal to one Planck length. If you existed as a theoretical ant with length less than a Planck length, you would fall through the actual fabric of the universe and cease to exist in our observable dimensions.



So as you move, finite amounts of molecules in your body move over finite amounts of space. Incorrectly analyzed mathematically: infinite points in your body move over infinite amounts of points in space, so it's infinity over infinity. And we know anything divided by itself equals one... one stupid argument.

so...

Motion = possible

any questions?

I've got a couple of questions:
1. You say anything divided by itself equals one. Infinity is not a number. Infinity divided by infinity is meaningless. Furthermore, in calculus, when the numerator and denominator of a rational function each increase without bound as x increases, the limit of that function is not necessarily 1.

2. Is DeBroglie wrong about all matter having wave characteristics, although the wavelength is too short to be measured because it is smaller than the planck length? Related to this, I thought the jury was still out over the debate between time moving in increments (i.e. the planck time or less) or time being continuous...

 

[thoro86]

I thought they already solved this paradox using calculus????

 

[madeupfacts]

I thought it would be more like, to move you have to go from 0 to x velocity in amount of time. So how can infinite acceleration be possible?

 

[Special K]

One explanation I liked can be found in the wiki article:


link

It bascially shows that while you can divide a finite length into a collection of infitesimally small intervals, the amount of time needed to traverse those intervals likewise decreases. While I'm sure some mathematician would have some objection to the explanation, I think it works well for anyone else.

Not to hijack the thread, but I think a similar but more interesting one is that of the supertask.

Suppose you are able to flick a light switch on and off arbitrarily fast, and that it takes 0 time for the switch to move from on->off, and vice versa. Also suppose the light is initially off. Now, after 1 minute, switch the light on. After another 30 seconds, switch it off. After another 15 seconds, switch it back on. Keep halving the time interval and flip the switch each time. What state is the light in after 2 minutes?

This is known as Thomson's Lamp

 

[theMan]

Originally posted by: 1prophet

Originally posted by: lexmark
lets say you were trying to travel from 0ft to 5ft.

there are an infinite amount of points between the two points right (4.98, 4.998, 4.99999999998, etc.)?wouldnt you have to pass through an infinite amount of points to reach to 5ft? how would you reach 5 if there is always a small distance to travel? (4.9999999999999999999999 ft?)

Eventually your measurements will probably hit this wall if you keep going smaller.

i was waiting for someone to post that. but, i really dont think it has anything to do with this.

 

[tweakmm]

Originally posted by: gabriel87120

Originally posted by: Evadman
Do some research on a 'plank' unit. space can not be broken up into an infintesimal amount of pieces, there really is s 'smallest' unit.

Take it from me, I am a physicist. The guy I am quoting stated the answer.

Points are not physical, you do not "move along a series of infinite points" because technically they aren't there. You do however move along a series of finite planck lengths during a finite amount time.


To clarify this nonsense further. If you try to solve this problem all the rhetoric in the world will not help you, unless it's mine lol. Read below. Mathmatically, a "series of infinitely small points" implies ONE SINGLE POINT if you are intelligent enough to chew on that. IE, placing infinitely small amounts of a substance into a bucket over an infinite amount of time, you still have a bucket thats empty. All those infinite amounts of little "zero" points next to each other extend over a total distance of zero. A point has NO REAL PHYSICAL EXISTANCE and is only a theoretical pinpoint of a relationship between an independent and dependent variable of a closed system. Calculus and even algebra depends on these "zero distance" points to work. But when did you ever walk to the store on a zidewalk paved with zeroes? So know this, to have independent and dependent variables, one must imply physical separation of the two (because if all variables were the same, all points in the universe are of value = 1, because var A = var B = var C).
If all values were one, then the sky wouldn't be blue if the grass was green. Separation of variables defines a finite nature of the physical characteristics of the universe. if everything were indeed points, then you wouldn't be here to observe the universe anyway (which itself would be curled up in an empty bucket of nothingness. Analyzing this problem incorrectly shows that not only motion is not possible, but neither is space, time, and pretty much everything alltogether.

The measurements of the universe are actually finite in its basic structure. Think of a knitted sweater, the thread being the universe's material, and the holes being the nothingness having diameter equal to one Planck length. If you existed as a theoretical ant with length less than a Planck length, you would fall through the actual fabric of the universe and cease to exist in our observable dimensions. So as you move, finite amounts of molecules in your body move over finite amounts of space. Incorrectly analyzed mathematically: infinite points in your body move over infinite amounts of points in space, so it's infinity over infinity. And we know anything divided by itself equals one... one stupid argument.

so...

Motion = possible

any questions?

Now that is a good answer. :thumbsup:

 

[f95toli]

It is also wrong..
You do not need to invoke the Planck length to explain this. Ordinary calculus is enough

Take it from me, I am also a physicist

 

[PigCorpse]

A point is undefined.

 

[Exterous]

Now, its been a few year since my physics classes so correct me if I am wrong but, isn't the distance of 5 ft a point? - an arbirtarty distance that no one can reach exactly becuase no one has an instrament capable of reaching exaclty and only exactly 5ft (and when dealing with differences so small that no one can agree that on what value that 5 ft actually has - and at these small incraments doesn't the issue that measuring something changes its characteristics comes into play?)

We live in a world of physical generalities

 

[imported_shader]

1. You say anything divided by itself equals one. Infinity is not a number. Infinity divided by infinity is meaningless. Furthermore, in calculus, when the numerator and denominator of a rational function each increase without bound as x increases, the limit of that function is not necessarily 1

i don't want to sound overly anal, but i wanted to reply to this and clarify. correct, infinity is not a number, but infinity divided by infinity is not neccessarily meaningless. as was stated previously infinity is not a number so it is not very accurate to say infinity divided by infinity on its own, but rather as the result of a limit (which is what this discussion is surrounding). now, if the result of a limit of a function is infinity over infinity, that is called an indeterminate form (which could be deciphered as meaningless). in some cases though the limit of a function which results in the indeterminate form of infinity / infinity can be obtained using l'hopital's rule, therefore yielding an actual limit (and could be generally interpreted as having meaning).

 

[Braznor]

OP, if you consider the distance between two finite points as infinte (as based on your assumption of it being divisible into infinite units) then the object in motion is also moving in infinite speed when compared to the same scale of infinite divisible units. SO motion is perfectly possible in such a scenario.

 

[bobsmith1492]

Heh, look up the impulse function and chew on that for a while: a line with infinite height and zero length with an area of one... Math rocks.

Regarding infinity/infinity, it depends on which "infinity" is getting to infinity faster. You can't define a number "infinity," only the limit as a function approaches infinity. I.E., if you had y(x)=(e^x)/(x^34235), as x -> infinity, what would y go to? You can't just plug in x=infinity, because then you get infinity/infinity. Instead you take the limit. In this case, using L'Hopital's rule (best rule ever...), lim y(x), x-> infinity, = infinity. You have to go case-by-case in tricky mathematical conditions like infinity/zero/infitessimally close distances.

 

[gsellis]

If you are having problems grasping the concept of infinity, drive across Kansas on I-70 at 55mph. Infinity is as long at that feels, + 1.

And since I am not taking this that seriously, we kept trying to prove in college that a 3 dimensional solid could be transformed into 2 dimensional infinite plane. Unfortunately, we only meet with limited success. I think was our test method that was flawed. We used a shoe and any random cockroach.

:laugh: