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CATEGORY: What's Ultimately Possible in Physics? Essay Contest (2009) [back]
TOPIC: Unification and the Limits of Knowledge by Marcelo Gleiser [refresh]
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Author Marcelo Gleiser wrote on Oct. 2, 2009 @ 21:46 GMT
Essay Abstract

I examine the question of whether it is possible to construct a final theory of Nature in a reductionist sense. Complete unification implicitly assumes total knowledge of physical reality. Can such knowledge be obtained? I examine two fundamental limitations which indicate that the answer is in the negative. To begin, science cannot explain the problem of the first cause, even within a valid quantum mechanical formulation of gravity. Also, our knowledge of reality depends on a fundamental way on our measuring devices. These, in turn, are subject to technological and, at a deeper level, to quantum mechanical limitations. Since we cannot measure all there is, we cannot know all there is. Thus, the boundaries of measurement set the limits of physics and of our explanations of physical reality.

Author Bio

Marcelo Gleiser is the Appleton Professor of Natural Philosophy and Professor of Physics and Astronomy at Dartmouth College. He has authored over 80 refereed publications and is a fellow of the American Physical Society. The recipient of a Presidential Faculty Fellows Award from NSF and the White House, Gleiser is also a very active science popularizer, having authored two award-winning books and often appearing in TV documentaries and radio interviews. His new book, expanding on some themes explored in this essay, will be published spring 2010 by Free Press.

Download Essay PDF File

Mark Stuckey wrote on Oct. 3, 2009 @ 03:23 GMT
Dear Marcelo,

Our essay deals precisely with how to avoid the issues of your essay (and other problems confronting dynamical unification). Of course, it's impossible to determine scientifically, by definition, whether facts exist beyond empirical verification. I don't see that this necessarily undermines unification, as we point out. The essay author is listed as "Silberstein." I'd be interested in your response.



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Helmut Hansen wrote on Oct. 3, 2009 @ 07:32 GMT
Dear Mr. Gleiser,

I have read your essay and I disagree, because I believe that something like a transcendent foundation is the key to a deep and penetrating understanding of the physical universe.

It is of course impossible to measure something, which is described as being of transcendent nature. But just but this very impossibility, not to be measurable, implies that the physical universe must have a very specific structure. Or in other words: Transcendence is with respect to the physical universe a highly restrictive condition. It restricts how the universe could look like in such a far-reaching way, that only o_n_e structure is likely. I found that a Universe which bases upon a transcendent foundation must indeed have a certain kind of a radical non-dual structure. And this derived structure is actually measurable. It seems that our universe does really have such a structure. Therefore, it can be assumed that our universe is actually based on a transcendent cause.

The message of this discovery is: If the ultimate foundation of our universe is really of transcendent nature, then there is, in principle, no way, to measure this foundation itself. The only way we can deal with it is to turn around our perspective and to ask for the physical conditions which have to be there in the case of such an unusual foundation.

Further detail you can found in my essay: TAMING OF THE ONE

Kind regards

H. Hansen

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Mohammed Sanduk wrote on Oct. 3, 2009 @ 12:47 GMT
Dear Marcelo,

I like your example of the anthropologist. Yes our knowledge of microscale creatures are for the "observed creatures". So we know the "observed electron" not the electron without observation. The knowledge (experimental investigation) has unavoidable

effect. So concepts like particle , complex wave in Quantum Mechanics may be related to this observation effect. Then the system of particle and complex wave is the observable model for something there.

This what I have found when I was considering a model has been proposed as a Three Wave Hypothesis (TWH) by Horodecki (please note my essay). According to that TWH I found a system (gear) represents the observable particle and its complex wave. This model is exactly similar to the your model of the tribe with the anthropologist. This model is speculative as you have mentioned "We may speculate about what’s beyond our measuring abilities, and some of theses speculations may even be correct".

Many thanks for your interesting article.

Mohammed Sanduk

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Philip Vos Fellman wrote on Oct. 4, 2009 @ 18:21 GMT
Hi Marcelo:

Thank you for a very thoughtful essay. In considering the difficulties surrounding the concept of "first cause" you might enjoy taking a look at Peter Lynds' piece "On a Fininte Universe with no beginning or end", ( which offers a novel solution to the usual first-case dilemmas.



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Anton W.M. Biermans wrote on Oct. 5, 2009 @ 11:56 GMT
‘… science cannot explain the problem of the first cause (…) Also, our knowledge of reality depends on a fundamental way on our measuring devices …’

The idea of a first or primordial cause is, like causality itself, an entirely religious concept, just like the idea that there exists some reality which if we wouldn’t affect it with our observation we could see in all its pure glory. Instead of saying that the observation affects what there is to see, we should take this influence as an indication that particles or objects perhaps aren’t just the source of their interactions, but their product as well. In a universe which has to create itself out of nothing (see Mechanics in a Self-Creating Universe) where things and events create each other, there’s no place for such an absolute kind of reality, for causality nor for interaction-independent properties.

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Terry Padden wrote on Oct. 11, 2009 @ 13:23 GMT

A well written essay.

Re. your First Cause issue: Before SR there was an aether and an absolute space and a preferred reference frame etc.. SR created all (inertial) observers / reference frames equal such that ANY one of them could be the preferred reference frame.

All we need to do with causality is close the causal chain (bottom to top and/or vice-versa) to form a loop - then a miracle: ANY cause can be the first / last cause. Easy really; just another form of relativity. We just need the new maths (see my essay) for closing causal chains. Probably some kind of (Co) Homology.

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J.C.N. Smith wrote on Oct. 14, 2009 @ 15:54 GMT
Mr. Gleiser,

Thank you; your essay was a joy to read. I have already added your book, 'The Dancing Universe,' to my Amazon shopping cart, and look forward to reading it.

Your book may describe a myth which has long been a favorite of mine. It relates the story of the wise man from an earlier era who was teaching "cosmology" to his avid disciples. "The Earth upon which we live," he explains, is actually the back of a gigantic tortoise. "But, Master," asks one of his disciples, "what is the gigantic tortoise standing on?" To which the Master replies, "It was revealed to me in a dream that the tortoise is standing on the back of an even more gigantic elephant." "Ah, yes," replies the disciple, "that is very good! But then what is the elephant standing on?" To which the Master was forced to reply, "That, my son, even I do not know."

I tend to view the lot of humankind as being very much analogous to the lot of a dog riding in the back of a pickup truck. Much as the dog may enjoy riding in the truck, it has no concept whatsoever of the internal combustion engine which powers the truck. This is not because the dog is "faulty" in any way, nor is it because internal combustion engines are intrinsically impossible to comprehend; it simply reflects the fact that dogs' brains have not evolved sufficiently to comprehend these things. In a similar way, I suspect that much as we humans may enjoy our little ride through the universe, our brains have not evolved sufficiently to fully comprehend the engine which drives it.

Regardless of how wonderfully our brains eventually may evolve in the future (assuming, of course that we don't stupidly erase ourselves or become erased by some impersonal cosmic disaster before that can happen), I suspect that we may never learn exactly what it is that the elephant is standing on. But that could be a good thing, because we are energized most profoundly and most joyfully by our (hopefully never ending) quest to understand more about the universe than we already do. Today, internal combustion engines, tomorrow, the universe.


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Eckard Blumschein wrote on Oct. 29, 2009 @ 16:36 GMT
Dear Marcello Gleiser,

You are someone who observes and interprets nature. Perhaps you will have to have a fertile fantasy as well as to be able controlling it.

Hopefully you will appreciate that I tried to remind of the important contribution made by Thommy Gold before he got a cosmologist.

I wonder why virtually everybody including you a priori excludes fundamental mistakes that possibly let to unrealistic expectations. You have definitely solid mathematical knowledge. Do you believe that my points are unfounded?

I argue: Future evades measurement. Isn't this true? Wouldn't negative elapsed time correspond to negative distance? The reason for me to ask such question is a very practical one. I hope for encouragement.



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Nick Mann wrote on Oct. 31, 2009 @ 21:27 GMT
"As with any builder, we need the materials and the joining rules. Beyond that, there is only metaphysics. Second, our knowledge of physical reality depends on our measuring devices. Our ever-changing vision of the cosmos, from Earth to Sun-centered, from static to expanding to accelerating universe, is fundamentally tool-driven ..."

Yes. And of course there's an historic tendency to depend perhaps too much on the mechanisms du jour for our fundamental metaphors, concepts and theories. What kind of computer is the universe and what program does it run? How about just possibly no kind and none?

Your essay is a breath of fresh air, a healthy dose of common sense. Thank you.

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Andre Jones wrote on Jan. 6, 2017 @ 18:15 GMT
Unfortunately, humans don't have all the necessary knowledge to fully understand the universe and I'm not sure they will ever do. I'm not a UFO guy, but when I read Bob Lazar's story about advanced propulsion technologies based on antigravity waves, space distortion and so on, I believed that could be possible, although it might have sounded crazy for a lot of people.

The physics we know can be defied, but some powerful politicians and militaries are hiding this from the general public.

Andre Jones


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