The Naked Scientists

The Naked Scientists Forum

Author Topic: Is Space Infinite In All Directions?  (Read 3144 times)

Offline D

  • Jr. Member
  • **
  • Posts: 32
    • View Profile
Is Space Infinite In All Directions?
« on: 14/06/2015 19:31:47 »
When we look in to space let say with a telescope, no mater how many times we zoom in theirs always more. Since space is infinite those that applies to microscope as wall? If space is infinite that would mean no mater how far we zoom in with a microscope there will always bee more (infinite) that would mean that theirs things so tiny that atom would be like the galaxy to some other tiny particles.


 

Offline chiralSPO

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 1879
  • Thanked: 144 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #1 on: 14/06/2015 19:41:29 »
Space is not necessarily infinitely divisible. Quantum mechanics arises partly from the simple notion that not everything can infinitely divisible--that there are smallest possible pieces of things, called quanta.

On the other hand, just because something cannot be subdivided into smaller pieces doesn't mean that it can't get any smaller. In accordance with theories of relativity, observations made from different frames of reference can disagree about the size of something. The faster something is moving relative to an observer, the smaller it will appear (https://en.wikipedia.org/wiki/Length_contraction). This is only noticeable with really (REALLY) fast speeds, but for an observer moving at a velocity arbitrarily close to the speed of light relative to what they are observing, the thing that they are observing will be arbitrarily small.
 

Online Bill S

  • Neilep Level Member
  • ******
  • Posts: 1827
  • Thanked: 12 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #2 on: 14/06/2015 20:17:32 »
Quote from: Chiral
Space is not necessarily infinitely divisible. Quantum mechanics arises partly from the simple notion that not everything can infinitely divisible--that there are smallest possible pieces of things, called quanta.

On the other hand, just because something cannot be subdivided into smaller pieces doesn't mean that it can't get any smaller.

Thatís a fascinating thought, Chiral.  Are you saying that although it cannot be divided, a quantum could somehow become smaller?  I need help with that!

Following your relativistic line of thought, I can see that a quantum of something travelling at close to light speed would, at least in principle, be length contracted, but that would be only in the reference frame of the observer, nothing physical would happen to the quantum in its own reference frame.  If there is no one in another reference frame observing the quantum, in what sense could it ever be considered to become smaller?

If there is a reference frame in which a quantum is length contracted by 50%, how does that differ from dividing it by 2, in that reference frame?
 

Offline jeffreyH

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 3923
  • Thanked: 53 times
  • The graviton sucks
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #3 on: 14/06/2015 20:31:28 »
If it were possible to measure the Planck length in a local frame of reference then every frame of reference would make the same measurement. If length contraction has occurred in a particular frame then a remote observer would observer 1 Planck square area to be rectangular rather than square. This has a bearing on the entropy of the surface of a black hole event horizon for remote observers. Although for the local observer this will not be apparent.
 

Online Bill S

  • Neilep Level Member
  • ******
  • Posts: 1827
  • Thanked: 12 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #4 on: 14/06/2015 23:35:03 »
Quote from: Jeffrey
If it were possible to measure the Planck length in a local frame of reference then every frame of reference would make the same measurement. If length contraction has occurred in a particular frame then a remote observer would observer 1 Planck square area to be rectangular rather than square.

That makes sense, but still does not address the fact that the remote observer sees a "1 Planck square" of which one side is less than the Planck length, in his reference frame, therefore it is a fraction of a quantum of length.
 

Offline Ethos_

  • Neilep Level Member
  • ******
  • Posts: 1277
  • Thanked: 14 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #5 on: 15/06/2015 00:50:03 »
From what I understand about the quantum state, whether Planck Length, Planck Mass, or Planck Time, such units are not necessarily the smallest units possible. They are simply the smallest measure of such units which we can calculate mathematically given the criteria available for such calculations, such as the speed of light.
 

Offline chiralSPO

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 1879
  • Thanked: 144 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #6 on: 15/06/2015 03:23:20 »
From what I understand about the quantum state, whether Planck Length, Planck Mass, or Planck Time, such units are not necessarily the smallest units possible. They are simply the smallest measure of such units which we can calculate mathematically given the criteria available for such calculations, such as the speed of light.

I share that understanding. But it may also be that space is quantized, whether that is at the Planck limit or smaller we probably can't know...
 

Offline PmbPhy

  • Neilep Level Member
  • ******
  • Posts: 2762
  • Thanked: 38 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #7 on: 15/06/2015 14:01:56 »
Quote from: D
When we look in to space let say with a telescope, no mater how many times we zoom in theirs always more. Since space is infinite those that applies to microscope as wall?
Hi D. I'd like to welcome you to the forum.  ;D

I don't understand the question Since space is infinite those that applies to microscope as wall? so can you please restate it for me please? I have the feeling that you're confusing the terms telescope and microscope. Thank you.

If you're referring to a microscope then I can't see what makes you think that looking into a microscope will tell you anything about space being infinite. Please explain. Thanks.

Quote from: D
If space is infinite that would mean no mater how far we zoom in with a microscope there will always bee more (infinite) that would mean that theirs things so tiny that atom would be like the galaxy to some other tiny particles.
If indeed you're referring to microscope then you have the wrong idea about space being infinite. Also, an atom in no way resembles a galaxy. A galaxy is understood in classical terms while an atom can only be understood using quantum mechanics.

Quote from: chiralSPO
Space is not necessarily infinitely divisible. Quantum mechanics arises partly from the simple notion that not everything can infinitely divisible--that there are smallest possible pieces of things, called quanta.
That is incorrect. The energy of a particle is only quantized when its in a potential well of some kind. The energy of a free particle is not quantized.
« Last Edit: 15/06/2015 16:24:05 by PmbPhy »
 

Online Bill S

  • Neilep Level Member
  • ******
  • Posts: 1827
  • Thanked: 12 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #8 on: 15/06/2015 16:26:34 »
Quote from: Chiral
  But it may also be that space is quantized, whether that is at the Planck limit or smaller we probably can't know...

Possibly 12 months or so ago I read something about work that demonstrated that if space is quantized, the quanta must be smaller than the Planck length.  It may have been in New Scientist; I'll see if I can trace it.
 

Offline D

  • Jr. Member
  • **
  • Posts: 32
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #9 on: 15/06/2015 16:34:53 »
Quote from: D
When we look in to space let say with a telescope, no mater how many times we zoom in theirs always more. Since space is infinite those that applies to microscope as wall?
Hi D. I'd like to welcome you to the forum.  ;D

I don't understand the question Since space is infinite those that applies to microscope as wall? so can you please restate it for me please? I have the feeling that you're confusing the terms telescope and microscope. Thank you.

If you're referring to a microscope then I can't see what makes you think that looking into a microscope will tell you anything about space being infinite. Please explain. Thanks.

Quote from: D
If space is infinite that would mean no mater how far we zoom in with a microscope there will always bee more (infinite) that would mean that theirs things so tiny that atom would be like the galaxy to some other tiny particles.
If indeed you're referring to microscope then you have the wrong idea about space being infinite. Also, an atom in no way resembles a galaxy. A galaxy is understood in classical terms while an atom can only be understood using quantum mechanics.

let me refreace it i use the microscope exmaple so people whould understand my question batter (Microscope is the direction) and by atom i only meant the size. for example i was saying that if space is infinat in all direction then theres things so tiny that imagine a size of a single atom and a aproximate size of the galaxy theres a massive difreants now what im saying is that there could bee things so small that the atom would seam like a galaxy in comperasing.

« Last Edit: 15/06/2015 16:58:47 by D »
 

Offline Ethos_

  • Neilep Level Member
  • ******
  • Posts: 1277
  • Thanked: 14 times
    • View Profile
Re: Is Space Infinite In All Directions?
« Reply #10 on: 15/06/2015 22:45:04 »
now what im saying is that there could bee things so small that the atom would seam like a galaxy in comperasing.
Now that's more understandable sir. And for my own speculation on the subject, I can see infinity reaching in both directions, macroscopic and microscopically. So yes to a certain degree, if this speculation is correct, then a cluster of atoms might in a very limited way resemble a galaxy of stars. But consider this; At the atomic level we are confronted with the uncertainty principle. So identifying the position and momentum of individual electrons would still be quite difficult if not impossible.
 

The Naked Scientists Forum

Re: Is Space Infinite In All Directions?
« Reply #10 on: 15/06/2015 22:45:04 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums