Quantized Space & Time

Moduli

mbkennelHow is this known? Is there clear experimental disproof against any such kind of theory or only certain classes of such? (and what are they?)

Yes, any discreetness of spacetime would cause the speed of light to depend on wavelength (very high energy light would travel at nearly c, and lower energy light would travel at less than c). The difference in speeds is small, but when traveling for very long amounts of time (millions or billions of years), the difference in arrival times would be easily large enough to measure. But for astronomical sources, we see no such difference (very far away things don't look delayed compared to very close things).

There are other bits of proof, too, but this is the easiest to understand.

So, in other words, as far as we can tell space is both non-dispersive and completely linear to photons.
At what wavelengths do we know this? Is it from gamma ray bursts which stay bursts and don't turn into a slide-whistle?

It's cool for freshman physics, but isn't that kind of a downer? CERN is coming up with not too much interesting, can't get ideas from astrophysics. Standard Model is an ugly hack with far too many #define YET_ANOTHER_FCKING_MIXING_ANGLE xxxxx, but no experimental hints anywhere.

ChaoticOrder
reply to post by Moduli

 

Yes, any discreetness of spacetime would cause the speed of light to depend on wavelength (very high energy light would travel at nearly c, and lower energy light would travel at less than c). The difference in speeds is small, but when traveling for very long amounts of time (millions or billions of years), the difference in arrival times would be easily large enough to measure. But for astronomical sources, we see no such difference (very far away things don't look delayed compared to very close things).

It's the vacuum fluctuations which is supposed to cause the photons to vary in speed, not the quantization of the vacuum.

I thought that these came out joined together in second quantization.

ImaFungi
reply to post by mbkennel

 

Thank you for the reply.

I really dont get how it can be both wave and particle like objectively. It cant be.

Feynman said that nobody ever really understands quantum mechanics, they just get used to it.

Mother Nature doesn't give a crap about our inability to understand Her. sort of like this.
say particle/wave duality again

Bedlam

ImaFungi

No in the nature of numbers there are infinites between 2 abstract points 1 -------------2 . But in reality there is no evidence that there is infinite amount of space, or potentially infinite amount of points (means the same thing) between two points.

Points are dimensionless. That's the definition of a point. It has location, but no extension. If you want to start trying to redefine "point" then you're going to have to get everyone to go along with it, but a point has no dimension. No volume. No length. It's a point. That's why it's a point.

Yes in abstract, mathamatical geometry. But in physical 3 d space, dimensionless points dont exist, neither do infinite dimensionless points between 2 arbitrary points.

reply to post by mbkennel


What you mean by linear photons and non-dispersive, is that it is as if the EM/photon field is 3d, yet when the event of a charged particle creating a photon occurs, at that exact point it is as if the electric and magnetic components of the EM field 'zipper or snap or dominoes' together in a sequential order, not allowing the energy to leak 3dimensionally like that of sound, or like when light is scattered in air? Could it be that the pressure from the totality of EM field (maybe something to do with the coupled particles in it as well) is what does not allow the linear photon from spreading out 3dimensionally?

reply to post by mbkennel



Im claiming that mother nature is not paradoxical, truth is logical. Nature at every level makes sense, because if it didnt it wouldnt work. So I am claiming that the physicists are the ones with the problem, I am saying physicsts must prove that it is logical, that it makes sense for 'something' to be a particle and wave, at the same time, how is this described, it is paradoxical because a particle is not a wave by definition and a wave is not a particle by definition.

reply to post by ImaFungi


Well, as you know, nothing unreal exists. It's Kiri-kin-tha's first law of metaphysics, after all.

ImaFungi
reply to post by mbkennel

 

Im claiming that mother nature is not paradoxical, truth is logical. Nature at every level makes sense, because if it didnt it wouldnt work. So I am claiming that the physicists are the ones with the problem, I am saying physicsts must prove that it is logical, that it makes sense for 'something' to be a particle and wave, at the same time, how is this described, it is paradoxical because a particle is not a wave by definition and a wave is not a particle by definition.

Ima

you are looking at this from a strange perspective imo. Physics does not even attempt to find truth or tell us anything at all about the nature of reality, thats for the philosophers. Physics just models phenomena, this can be useful for technology, nothing more. Wave, particle or something else, its just a math model that says nothing about the reality of a photon. They are just two convenient ways to model its properties under certain conditions.

Will

ImaFungi
reply to post by mbkennel

 

What you mean by linear photons and non-dispersive, is that it is as if the EM/photon field is 3d, yet when the event of a charged particle creating a photon occurs, at that exact point it is as if the electric and magnetic components of the EM field 'zipper or snap or dominoes' together in a sequential order, not allowing the energy to leak 3dimensionally like that of sound, or like when light is scattered in air? Could it be that the pressure from the totality of EM field (maybe something to do with the coupled particles in it as well) is what does not allow the linear photon from spreading out 3dimensionally?

No, nothing like that. Moduli said that there are experimental reasons to believe that there is no fundamental quantization of space because (as I interpret his comments) that would result in observable astrophysical phenomena which are not observed.

non-dispersive = all frequencies travel at the same speed. Dispersion is still a linear effect (in the sense of linear differential equations). Light through matter, such as glass, undergoes dispersion from physical interaction with the glass. In long distance fiber optic cables, the signaling is done at a carrier frequency close to the frequency of minimum dispersion through this special glass. Dispersion will distort waveforms over longer distances (fourier vs laplace view but it's still the same physics) and limit the speed of information transmission as successive bits start to interfere physically.

Moduli referred to observational results which show no dispersion for very long range astrophysical events. For reasons I don't understand this constrains many theories about quantized space and makes them unlikely and incompatible with observations. (M: did I understand this right?)

Linearity means that you can add two things of the same intensity and the result is exactly twice (no more no less) than what you put in, there is no additional effect creating something at a different frequency. Changing the microscopic nature of space might conceivably induce a small nonlinearity but we haven't seen it.

reply to post by mbkennel


In free outer galactic space, when an electron creates a photon, is there an EM wave that forms from the point of creation outwards 3dimensionally like a spherical rippling wave?

reply to post by will2learn




Reality exists will2learn. Beyond what men feel and think and want and think they know, reality exists exactly as it is. After much time, man wanted to know more about reality, the only way to do this is the slow and steady process of science (yes with philosophy... which my definition of philosophy is; thought which includes the totality of possible thought...and yes science requires thought). I understand what you mean, models and abstractions of reality, but the only way to further knowledge and understanding of reality is through models and abstractions. If not knowing reality completely, the hope is in constantly knowing reality more and better, and more and better. Are you suggesting that the true establishment and mechanisms, hardware and software of reality may be inaccessible to us, and no matter the physical prodding and mental thoughting we will never be able to truly take a deep breathe in a moment of content clarity and comprehension? If not science, what means of discovering the workings of nature do you suggest?

ImaFungi
reply to post by will2learn

 

Reality exists will2learn. Beyond what men feel and think and want and think they know, reality exists exactly as it is. After much time, man wanted to know more about reality, the only way to do this is the slow and steady process of science (yes with philosophy... which my definition of philosophy is; thought which includes the totality of possible thought...and yes science requires thought). I understand what you mean, models and abstractions of reality, but the only way to further knowledge and understanding of reality is through models and abstractions. If not knowing reality completely, the hope is in constantly knowing reality more and better, and more and better. Are you suggesting that the true establishment and mechanisms, hardware and software of reality may be inaccessible to us, and no matter the physical prodding and mental thoughting we will never be able to truly take a deep breathe in a moment of content clarity and comprehension? If not science, what means of discovering the workings of nature do you suggest?

Ima

Reality may or may not exist, the laws of physics don't make it any less or more. They just allow us to play in the envelopes that the laws of nature have as bounds. Ask a man who jumps from a plane about the laws of gravity, they add nothing to the reality of falling from a plane.

I agree that physics allows us to further knowledge, but it adds nothing o the experience of red. Philosophy used to be a great discipline when it was natural philosophy, but it was stripped of its guts when science added experiment and repeatability to the system. Now it just adds color to equations and models that people have a hard time imagining.

Science just underpins the technologies or toys we have at our disposal. We have virtually no first hand experience of the particles which take up so much time in discussion. As such I'd say that they add little to our realities, tho the toys certainly are fun to play with, even tho the experience is 2nd or 3rd hand by the time we sense it.

I quite like the discussions on the nature of space or gravity, purely because like fiction they can open up new channels of research or different goals for the great thinkers. I am pretty sure that until we get to the macroscopic effects of the fundamental forces or particles we really have no reality connected to them. As you point out it is abstract and as such has no bearing on the real world besides the time expended in our lives. In the disciplines of particle science it is unlikely we will ever get to really sense them, but we may get to enjoy the benefits of some unknown energy or mechanic not obvious through experience. That is enough in itself, after all look at what the electron has brought us.

We are not trying to establish reality through physics, we are just trying to find things that might or might not be useful at our scale.

Will

reply to post by will2learn


No we are only trying to find out what reality is through physics, innovation is a by product of our knowledge and seeking. You are referring to the reality of subjective experience, I (and physics) am referring to the reality of objectivity, which when thorough enough covers subjectivity. Physics can tell you everything about the experience of jumping out of a plane, and why you fall.

Please stop making off topic posts, im interested in the discussion that was going on and you have touched upon it none, what have you brought to the table?

ImaFungi
reply to post by will2learn

 

No we are only trying to find out what reality is through physics, innovation is a by product of our knowledge and seeking. You are referring to the reality of subjective experience, I (and physics) am referring to the reality of objectivity, which when thorough enough covers subjectivity. Physics can tell you everything about the experience of jumping out of a plane, and why you fall.

Please stop making off topic posts, im interested in the discussion that was going on and you have touched upon it none, what have you brought to the table?

edit on 24-9-2013 by ImaFungi because: (no reason given)

I put a relationship between space and matter on the table, backed up by experimental results.

reply to post by will2learn


Ok so every plancks length of space is actual material/energy or field. There is no such thing in this universe as an area if even the smallest completely void of energy/matter? No area exposing some eternal primal nothingness which will always exist somewhere, the background to all something. There is no such thing as that, all that exists is this connected ball of energy called the universe? And we posit beyond its confines exists...?

ImaFungi
reply to post by will2learn

 

Ok so every plancks length of space is actual material/energy or field. There is no such thing in this universe as an area if even the smallest completely void of energy/matter? No area exposing some eternal primal nothingness which will always exist somewhere, the background to all something. There is no such thing as that, all that exists is this connected ball of energy called the universe? And we posit beyond its confines exists...?

Ima

Ima not sure I understand your english there, but the energy density of the vacuum at the planck length can be huge. It fluctuates enormously. Sometimes it spontaneously turns into energy or matter, check out the Casimir experiments. I think this indicates that space itself converts to stable forms of fundamental particles. When a quanta of space invagelates or twists in a certain way it causes a slight distortion in the fabric of space, essentially creating a gravity field as we know it. Surely when a particle of matter is made the gravity field changes, well if space wraps up it could affect the space itself.

Its all connected as you say

Will

reply to post by will2learn


Im asking; In the entirety of the universe, is there an area (even if the smallest possible area) that is not occupied by energy or matter or particles. If there is, what is the nature of that area, what is it?

mbkennel
So, in other words, as far as we can tell space is both non-dispersive and completely linear to photons. At what wavelengths do we know this? Is it from gamma ray bursts which stay bursts and don't turn into a slide-whistle?

Yeah, that's part of it. There's also measuring the shape of the spectrum for events that are relatively similar (like certain types of supernovas) for objects that differ in distance from us significantly. So we have good data over a wide range of wavelengths.

It's cool for freshman physics, but isn't that kind of a downer? CERN is coming up with not too much interesting, can't get ideas from astrophysics. Standard Model is an ugly hack with far too many #define YET_ANOTHER_FCKING_MIXING_ANGLE xxxxx, but no experimental hints anywhere.

Nah, that's interesting, because all of that weird random structure comes from somewhere. Not to mention there's still a lot we can't calculate from ordinary quantum field theories, such as a lot of nonequilibrium stuff and strongly coupled stuff. So there's still a lot of interesting stuff to discover, even with what we already know.

mbkennel
Moduli referred to observational results which show no dispersion for very long range astrophysical events. For reasons I don't understand this constrains many theories about quantized space and makes them unlikely and incompatible with observations. (M: did I understand this right?)

Yep.

ImaFungi
reply to post by will2learn

 

Im asking; In the entirety of the universe, is there an area (even if the smallest possible area) that is not occupied by energy or matter or particles. If there is, what is the nature of that area, what is it?

Ima

I doubt there is any measurable area or volume that is not dense with energy. On the larger scale it may average to zero. The only possible place, to my mind at least, is the voids created when the quanta of space wrap up on themselves. These truly empty spaces might be zero.

Will

reply to post by will2learn


Ok might be zero hm.. But what is it, what is it made of, its composition, the substance...where there is an area of no energy,particles,matter,radiation, what is it there? What is there, what is that? In an atom where there is no nucleus, radiation, quarks of any kind, electrons, what is there, what is it?