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A Question on Abiogenesis

You're both making the assumption that we would have to be able to measure the quantization itself. This is not correct; such a quantization would necessarily have effects on interactions at much larger scales.

Well, I carefully said the 'effect' would have to be smaller than our instruments can measure, for precisely that reason.

At some point any supposed effect may be constrained to be smaller than is compatible with the original theory, at which point it's time to go back to the whiteboard. But generally, absence of evidence, etc...

Isn't quantised space sometimes advanced as a possible solution to the neutrino mass/spin problem?
 
I'm not sure I entirely followed that second sentence, but the first is pretty clear.

The reason that there is a conflict between relativity and quantum mechanics is because quantum mechanics doesn't talk about the sizes of particles. The underlying assumption is that they don't have a size; that they are infinitely small. String physics solves this conflict not by proposing that space or time are quantized, but by proposing that particles aren't infinitely small, that they have some actual, though very small, size. By doing this, the infinities that plague the combination of GRT and QM disappear; and, since GRT is the field theory of gravity, we also get a quantum theory of gravity, and eventually a quantum field theory of gravity.

Thanks, I was asking hamme why he objected to the whole premise.

I am very comfortable with the universe being the way it is. Any apparent contradiction is a result of our perceptual overlay. the universe does not have to make sense to us it just is.

If we approach it one way and it looks one way and we approach it another and it looks different that is fine by me. Because it would appear that it is our understanding that creates the contradiction. I would expect different models to produce different results.

I was mainly trying to draw hamme out.
That spacetime is a continuum is a postulate that leads to relativity; in other words, space and time are not discrete, but continuous. That's what "continuum" means. We've tested relativity pretty extensively, and the most sensitive tests yet will be coming out in a month or two, when they're done crunching the Gravity Probe B data. So basically, unless we see some startling results, we're looking at more confirmation of GRT; and that in turn bolsters its postulates. The existence of GRT, and its effectiveness as a theory of physics, and it is spectacularly effective, argues very strongly that neither space nor time is quantized. Unless or until someone finds a problem with GRT, quantized space or time are not even worth talking about.
Again that sounds fine to me, the fact that packets of what appears to be quatized energy in the space time conitnuum and that therefore thos packets might be different than the way we think of them currently is just fine. QM is accurate and if GRT is accurate that is great. If the two contradict, which I am not sure they do, that is fine by my. I don't expect the universe to meet our desires for it to be consistent. It will resolve at some point and the models will change, becomeing more accurate.
Actually, measured in one axis, spin is "digital," since it can have only two values. The "non-digitalness" doesn't emerge until you try to measure the spin on more than one axis simultaneously; what you find is, you can't. When we talk about digital logic, we're talking about things that are either one way, or another way; but the Aspect experiment shows us that, unlike Schroedinger's Cat, which is either alive or dead inside the box whether we can see it or not, the spin on the second axis isn't merely unmeasurable; it literally HAS NO VALUE. And that is the consensus understanding of the underlying physical reality by the majority of physicists.
Which is fine by me, that would mean that the 'digital' value is an artifact of the way we look at it.
I really didn't follow this line of reasoning. Could you be a bit more explicit?

Trying to draw hamme out.
 
..Because states are quantized, it seems the most obvious thing to many people who don't think deeply to state that the universe must be digital. What they forget is three things:
1. The quantized states have the same values only for the same type of atom; atoms of different composition have different available states, and there is no restriction on the possible values these states can take on.
2. More importantly, these states can be "smeared" across a continuum of possible values, either (as you are no doubt familiar with) within a semiconductor crystal lattice, forming the "conduction band" and the other bands of energy states, which please note are not single values but collections of values all very close to one another but necessarily not the same due to Pauli exclusion, or by the action of a magnetic field on the orbits and therefore on the energy levels of the atoms.
3. Most importantly of all, once created, the photons can be continuously varied in energy level by relative motion of an observer, or by the presence of a gravity field or an acceleration on the part of either the source or the observer.

Reality is not digital. It is analog. These three examples prove it conclusively.
This post by you was not addressed to me. I had been away from the forum a few days when you posted this. I wonder now if this is what you expected for me to address.
If so, here is my response per each of your points:
1. The fine structure constant, as a result of theory corroborated with experiment is known to the precision of better than 10^10. The success of QED is extraordinary. Measurement of fine-structure is to a resolution of about 1KHz out of 300THz. Let’s see: from K, M,G,T,x100 is about 10^11, right? That’s the best we’ve done with theory corroborated by experiment. I’ve read that there are some physical properties measured to the precision of 1 part in 10^20!! But all that is gross in comparison to the level of discretization of space-time it makes sense to consider plausible. It seems to me you may be thinking of discretization at much larger scales than planck scales because maybe you expect to be able to detect it directly?
2. To talk about potential values of the quantum state is also not something that can be observed. This is an ideal construct. To say it is “smeared” is like my saying that real numbers are “smeared” between 0 and 1. ...Surely, in our imaginations. But what reality does the mathematical continuum actually possess? None! Potential quantum values are a mathematical construction that can be represented as taking on all real (or imaginary) values. But potential quantum values become realized as actual values upon measurement. So I am confused as to how you might expect the potential values that can't be measured to be evidence of continuum.
3. This third statement presumes continuum and then concludes in a circular fashion. Notice that the observer’s or source’s velocities are assumed to be continuous, which is used to conclude therefore that the photon’s energy can be varied continuously due to relativistic effects. Can you see how this is obviously a circular argument?

These three points you made all say the same thing to me. Something like “direct measurement reveals a universe that, if space-time is discrete, is so at a level that is much tinier than we can observe. Therefore, if they are so tiny we can't observe them, they must be infinitesimal."

My contention with this is that direct measurement may not be a source of evidence one way or the other – ever. I think the evidence will be found by starting with the proper interpretation of many things we already know. Subsequently that should lead to enough of the right mindset in theoretical formulation so that more evidence will come from new models that predict things for which we previously had no explanation.
 
At some point any supposed effect may be constrained to be smaller than is compatible with the original theory, at which point it's time to go back to the whiteboard. But generally, absence of evidence, etc...
Well, that was kind of my point: absence of evidence. Of course, it's not evidence of absence, but so far we don't have any and we've looked. So any consistent hypothesis we're going to make has to account for that absence, and the most straightforward is that the absence of evidence indicates that it's not there.

Isn't quantised space sometimes advanced as a possible solution to the neutrino mass/spin problem?
There are quite a few interesting ideas floating around. Heim, LQG, twistors (which is looking a little ragged lately), for example. I'm not sure which you might be referring to here. I'm also not aware that neutrino spin is a problem; I am familiar with the neutrino mass problem, but was under the impression that there was at least a proposed solution involving them changing into one another. Could you be more specific?
 
2. To talk about potential values of the quantum state is also not something that can be observed. This is an ideal construct. To say it is “smeared” is like my saying that real numbers are “smeared” between 0 and 1. ...Surely, in our imaginations. But what reality does the mathematical continuum actually possess? None! Potential quantum values are a mathematical construction that can be represented as taking on all real (or imaginary) values. But potential quantum values become realized as actual values upon measurement. So I am confused as to how you might expect the potential values that can't be measured to be evidence of continuum.
They become actual values as outcomes, not measurements. Measurements by humans are just one subset of outcomes. The observable distribution of outcomes are what reveal the underlying continuum. The distribution cannot be explained without the continuum. That's what Heisenberg at al have demonstrated.
 
They become actual values as outcomes, not measurements. Measurements by humans are just one subset of outcomes. The observable distribution of outcomes are what reveal the underlying continuum. The distribution cannot be explained without the continuum. That's what Heisenberg at al have demonstrated.
Actually, it was demonstrated by Aspect's realization of the EPR gedankenexperiment, but you're on the right track.
 
They become actual values as outcomes, not measurements. Measurements by humans are just one subset of outcomes. The observable distribution of outcomes are what reveal the underlying continuum. The distribution cannot be explained without the continuum. That's what Heisenberg et al have demonstrated.

There are many interpretations of "outcome" and "measurement" among quantum theorists. I do not take strong issue with your first two sentences here.

My interpretation of your third sentence is you say that the mathematical model suggests to you an underlying continuum. To me, it suggests that the mathematical model you mention is one constructed with continuous mathematical operators and functions. It is non-sequitor to say "therefore the reality is thus". You seem to suggest you are relating this to "measurement" but to collapse a set of wave functions in order to demonstrate via measurement a continuum, you would have to collapse an infinite amount and I don't think we have time to do that demonstration. ...and of course we only have measurement precision of a scant number of digits compared to that required to discern "continuum" (ludicrous understatement).

To say that the distribution cannot be explained without continuum is okay with me - it merely says (I repeat once again) that the model is continuous and so of course, in an obvious circular manner: the distribution is continuous.

...and what did Heisenberg demostrate that indicated reality is continuum? I've already stated Heisenberg's dE*dt<=h-bar is nonsense if you allow dt approach 0. This suggests minimums for s and t; certainly not continuum.

I'm sorry if I am missing something that you were trying to tell me, but if you are meaning to say something deeper than what I have understood from you, please, by all means illuminate. I really do want to distinguish your meaning from mere demonstration from the chosen continuous mathematical model. What measurable evidence does quantum distribution provide toward "continuum"?
 
I'm not sure which you might be referring to here. I'm also not aware that neutrino spin is a problem; I am familiar with the neutrino mass problem, but was under the impression that there was at least a proposed solution involving them changing into one another. Could you be more specific?

Neutrinos have only ever been observed with left-handed helicity, and antineutrinos with right-handed helicity. But if they have mass then they must exhibit both chiralities or contradict SR.
 
Neutrinos have only ever been observed with left-handed helicity, and antineutrinos with right-handed helicity. But if they have mass then they must exhibit both chiralities or contradict SR.
Oh my. SERIOUS research. I assume you'll give me a bit since you took a while yourself. ;)
 

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