Thoughts on Judaism

Thursday, March 10, 2005

Quantum Mechanics - The science of the simple

QM is the rallying point of so many religious "scholars", that one would think that the forefathers of this relatively new area of physics were Rebbes themselves. Promoters have used the formative ideas of QM to defend ideas such "cause not linked to effect", scientific support for the possibility of miracles, the power of the observer (or the davener) to influence the path of reality, and the innate issue of absolutism in science. The CR alludes to it here.

A short history is in order. Here is the poor man's intro guide to the subject. A good review of the subject with all of its linked concepts is necessary to proceed.

So in short, there are some observations, and 4 basic ways of understanding them.

We must begin with the Principle of Indeterminancy, put forth by Werner Heisenberg. It proposes that when one measures precisely the position of an object, one loses the abilty to measure its velocity accurately, and vice versa.

1) Copenhagen interpretation - This is the classical grandaddy of QM theory. Its basic tenet is that the observation of photons / light waves collapses the "wavefunction" and brings on the "reality". Its backbone experiment is the "double slit" experiment. Its flag is the Schroedinger cat "thought experiment". Its adherents were the who's who of the QM and subatomic particle world. In particular, its interpretation of Heisenberg, seems to assert in a macroreality that the inevitability of cause and effect are not clear cut. The reason why the two factors cannot measured accurately is because there is an indeterminancy in reality. While QM generally applies to subatomic quantized particles only, the urge of the apologist is apply this philosophically to all of physics. Copenhagen is a favorite of the apologist.

2) Multiworld Interpretation - Its basic tenet is also indeterminancy, in that an infinite numer of worlds exist and a different path is taken in each of them as choices arise. Its banner is the "physicist suicide" thought experiment. This is the interpretation that requires the most imagination and faith, but it is not a favorite of apologists.

3) Hidden variables - Its basic tenet is that there are inherent missing variables that account for the apparent indeterminancy. Einstein, in particular, (the E in EPR) promoted this view, arguing that Copenhagen abandons intuition and violates the theory of relativity. Its banner is the EPR paradox. It formed primarlily as an answer to Copenhagen.

4) Afshar's challenge to Copenhagen - More recently, a QM scientist by this name has claimed to show in reproduceable forum that he can break the basic experimental spine of Copenhagen, by observing the wave pattern and photon particle detection at the same time, refuting the notion that the "wavefunction" collapses on measurement.. He argues that the entire basis of the debate is flawed and that it is probable that the concept of photons and subatomic particles as "particles" is in error. We await the peer review of what would be a breakthrough in QM theory.

One observation that I had was that the CR, in the letter above, states:
"Need one remind our orthodox Jewish scientists, who still feel embarrassed about some ‘old-fashioned’ Torah truths, in the face of scientific hypotheses, that Heisenberg’s ‘principle of indeterminacy’ has finally done away with the traditional scientific notion that cause and effect are mechanically linked, so that it is now quite unscientific to hold that one event is an inevitable consequence of another, but only most probable? The 19th century dogmatic, mechanistic, and deterministic attitude of science is gone. The modern scientist no longer expects to find Truth in science. The current and universally accepted view of science itself is that science must reconcile itself to the idea that whatever progress it makes, it will always deal with probabilities; not with certainties or absolutes."

However in B'Or HaTorah, vol 9, page 47, Dr. Naftali Berg z"l claims that the CR told him that the Heisenberg Principle is "not satisfying from a Jewish perspective" because it reduces miracles that are so declared to be miracles into possible, albeit unlikely, natural events.

While this entire "macro world" (greater than Planck's constant) discussion is a bit presumptuous, it is still unclear what the CR actually said in this regard. On the one hand, he calls Heisenberg "universally accepted". In another place, he completely rejects Heisenberg and indeterminancy as an apologetic tool. In religious teachings, Chasidus, both he and his predecessor, the Rayatz, explain that "cause and effect" "Ilah v'Alul" is a real principle in nature, and use it as a parable to explain the difference between nature and G-dly choice. It is also unclear whether the CR meant Copenhagen, rather than Heisenberg. It is possible that in the context of the letter, the CR simply means that the scientists should hold a different view because of Heisenberg, without endorsing he prinicple homself.

I realize that some homework and background is required to follow the debate so in later posts I will try to stay with one subject at a time and examine it in light of its philosophical implications on Judaism. Note, I am not a QM physicist, so I will have to limit discussion to popular history and elementary level debate. My interest here is to examine QM as an apologetic tool. I think that it is overused and largely used in a false manner, which is detrimental to apologetics.


  • No. You got it wrong again.

    Heisenberg used for apologetics is unsatisfying. The Rebbe is being polite in this.

    Heisenberg as theory verified by experiment, is doing well. The support for it is enormous.

    Einstein's famous paper on hidden variables says there are not hidden variables.

    Re ashfur, you are not qualified to comment on it. I did not find any work by Afshar in peer reviewed journals, and I have not personanly seen his claimed measurements, so I am not prepared to comment on it either.


    By Anonymous Anonymous, at 12:25 AM  

  • Point by point

    1) Probably
    2) Agreed at QM level. It is the interpretation of Heisenberg Principle, not the principle itself, that is the issue. At the macro level, the principle makes no sense. We do not destroy the means to measure one parameter by measuring the other.
    3) Agreed, the point here was that there was and continues to be a lack of concensus on determinism within the qm world.
    4) Agreed, again, it was only an example of the dangers of using QM in apologetics. The Afshar experiment POTENTIALLY differentiates and proves determinism.
    5) Snide to be sure. But I am not making new postulates here. I am just warning against overstatement and selective data presentation, that are more damaging to apologetics than supportive of it.

    By Blogger Rebeljew, at 1:52 PM  

  • No one has any problems interpreting the Heisenberg principle, at least no one who actually works in the subject.

    There have been experiments and devices at the macro scale for decades. Lookup "Josephson Junction".

    The plain experimentally demonstrated fact is that there are situations where properties cannot be measured precisely, there are situations where properties do not exist at all, and there are situations where the effect produces tangible results without measuring either property individually.

    There is no "lack of consensus on determinism". The debates occured a very long time ago.

    The possibility that his experiments could cast any doubt whatsoever on quantum mechanics is at the extremes of unlikelihood. Potential is not the right word. See the crackpot index at

    Re aplogetics, the Torah does not need corroboration.

    Members of the Torah Science crowd have gone far beyond mere overstatement and data selection. Just look for the phrase "science has shown" or "science has proven". Whatever follows is pure fiction.

    By Anonymous Anonymous, at 4:46 AM  

  • We have a spaceship. We simultaneously know its position precisely and its momentum precisely.

    By Blogger Rebeljew, at 5:01 PM  

  • Your spaceship is presumably not a coherent object and even so, you will never know its position or its momentum to infinite precision.

    Probability distributions for large incoherent systems are extremely narrow, but not zero.

    Note that your example has nothing to do with quantum mechanics because of the number of incoherent objects. In a coherent system, the operative word for certain combinations of variables would be "and" rather than "or".

    By Anonymous Anonymous, at 7:46 PM  

  • Continuing ...

    The reason why you will never get even close to absolute precision is because of the noise in the measurement itself. Think about interpolating with real rulers and clocks.

    By Anonymous Anonymous, at 9:23 PM  

  • "Re aplogetics, the Torah does not need corroboration.

    Members of the Torah Science crowd have gone far beyond mere overstatement and data selection. Just look for the phrase "science has shown" or "science has proven". Whatever follows is pure fiction."

    The Torah does not need corroboration, but it must answer for things that appear the opposite of what we observe. Rabbits do not chew cud. Venus and Mercury can be farther from Earth than the sun (impossible in Rambam model). Teh human ovum, not blood, is the female seed. These things are not likely to change from science's standpoint. The methods of dealing with this are the subject of first post of this blog.

    In fact, the reason for discussing QM in the first place was BECAUSE there were those who would build that corroboration, one that I feel is built on a foundation of weakness, where QM is concerned. The underlying point of bringing Einstein, Bohm et al was to show that if we cannot establish a concensus on indeterminism, and we cannot, we are only taking a side in a scientific debate and basing our religious position on the fortunes of that side. That was the point of bringing Afshar. If some yukel from nowhere one day breaks the back of Copenhagen and / or MWI, what will become of all of the apologetics built on it. Most of these apologists are not conversant in any basic precept, other than what they have heard in a polemic. You obviously do not fit that mold.

    I think the points we are trying to make are largely the same, oddly enough. I do not disagree with the last line of the quote. However, when we declare Torah as the ultimate arbiter of truth, we cannot shun obvious observations and intuition. Call it sceince or just what one sees with their own eyes, but we do no service to deny that these things are so. We just drive off those that care to hear no more.

    By Blogger Rebeljew, at 12:31 AM  

  • That some people will be impressed by science, and that some will take advantage of this, is a problem that has been with us for a very long time.

    The main points here are that you are also not a scientist, that you frequently get it very wrong, and that your readers should be aware of this.

    For example, you seem to imagine that quantum mechanics routinely violates conservation of energy and that things are quantum mechanical because they are small, and then you bring this ridiculus thing about the spaceship. Your comment about "Copenhagen / MWI" (above) is at the same level. The vocabular is that of the popular press, the content is gobbledy gook.

    It is perhaps nice that you want to debunk the Torah Science crowd, but unfortunately you yourself are in some ways in the same category. You use pretension to borrow false credibility among the defenseless.

    By Anonymous Anonymous, at 10:37 AM  

  • Now lets take up two of your science questions:

    1) The interchange of the order of distances between the earth and planets is indeed an interesting question. Perhaps the place to start is to look up and see (i) if Rambam says the spheres are solid exactly, and (ii) if Rambam is saying Halacha or quoting an other source. Note that it is said that the geocentric view is the accepted pshat on Yehoshua.

    If so (to all the above), then perhaps we have a question. However, if I cannot find an answer to that question today, it is not going to hold me back from T'fillin.

    It is not a core issue, I do not have to be the one to resolve it, and my emuneh does not depend on it.

    2) Re quantum mechanics, you might notice that free choice was a difficult issue in the classical deterministic view of the universe.

    By Anonymous Anonymous, at 11:04 AM  

  • In the links to apologetics, especially in Chabad, there were those who set up, based on letters from the Rebbe, to conclude that science had concluded that causes and effects were not linked, a vast overstatement of the most radical of the radical. They wanted to learn from the famous Schroedinger cat thought experiment that, therefore, we all create or own reality, and, this is the objectionable part, SCIENCE PROVES THIS.

    I tried to attack this on all levels. First of all, the Copenhagen or classical Interpretation is one, in a progression of theories, some deterministic, like Einstein and Bohm, some not deterministic like Copenhagen and MWI. But my point was not to favor one of these over the others, but to point out that SCIENCE PROVES THIS is false. That is why I bring in Afshar. Just to point out that there is essential debate on the very substance going on at all times.

    In short, science does not declare that our daily reality is based on our perception of it. It does not declare that if we observe something a certain way, that it becomes that way. And that is what these peopole were trying to argue.

    I tried to show that:
    a) That is not what Copenhagen proposes
    b) The cat example says nothing like this.
    c) Copenhagen, to borrow a catchphrase, is a theory, a very nonintuitive one, and not a fact. (I think this is where you got hung up on this, but it is really a side point.)
    d) I also tried to show that yoou can't depend on one piece of fact for one thing, and thena competing fact for something else. Your point (2) was the beginning of that discussion. I was not arguing for determinism, just for the concept that there were and are deterministic models and nondeterministic models, of which the apologists favorite was only one.

    You have pointed out, as I did in my post, that I am not discussing this from the standpoint of a scientist, but of a logical person. I have no idea about if I have a toothache, whether I need a filling, a little time, or a major operation to make the pain go away. I go to a dentist. I expect the dentist to give me an explanation that makes sense and an action plan. If it does not sit well with me, I go to other dentists for other opinions and options. That is so with every area of knowledge, expert or not. Academics miss this sometimes.

    It funny that you declare my examples to be gobbledygook. That was the point. They were direct refutations of things that these apologists have said, in kind. Follow the links in the posts and see if I am exaggerating.

    By Blogger Rebeljew, at 10:22 AM  

  • You seem determined to appear as if you know something about science. Maybe this is a way of adding credibility to your other writings where you challenge and make fun of frum observance.

    Your readers should rather know that there are actual scientists (doctorate, institute member, publications, the whole nine yards) who after careful consideration have became frum, and in Chabad no less.

    A logical person will see this and say, “These are scientists and they are frum. I see that I do not know science, but they do. So whatever questions there may be, they are not such that I should let them separate me from being frum.”

    By Anonymous Anonymous, at 12:31 AM  

  • Science quiz:

    1) Is Copenhagen a theory or an interpretation? Does it tell us how to calculate something? How about MWI?

    2) Suggest three ways to recognize a crackpot. Is Afshar a crackpot?

    3) Lookup the triple stern-gerlach experiment (see Feynman Vol III). Which spin states exist for each possible measurement? What happened to the other states?

    By Anonymous Anonymous, at 12:58 AM  

  • "You seem determined to appear as if you know something about science. Maybe this is a way of adding credibility to your other writings where you challenge and make fun of frum observance."

    For starters, you show a sad misunderstanding of what I did here, before my retirement on February 27. My views are actually right of most rebel sites. We do poke fun of some of the sillier matters, especially scientific areas such as spontaneous generation, Ptolemaic science, medieval ideas on anatomy and reproduction and on. Many gedolim of yesteryear asked these questions and similar.

    Perhaps you should reread this from the post itself:
    "Note, I am not a QM physicist, so I will have to limit discussion to popular history and elementary level debate. My interest here is to examine QM as an apologetic tool. I think that it is overused and largely used in a false manner, which is detrimental to apologetics."

    That is my interest in the matter. That you refer to the writers as crackpots was the primary point I ever had in broaching the QM sucbject. THEY brought it up, not me.

    The second thing that you must understand is that people are leaving in droves, becuase they do not like the newfangled brand of drive up your nose, fundamentalist fanaticism that characterizes the yeshivas and the Charedim today. When young people ask "do we have to believe in spontaneous generation, creationism k'pashuto ... in order to be frum?", if we answer "yes and its really true because gibberish gibberish", they hear that their worst fears are realized. This is not just in kiruv but ffb kids! So I support the propogation of actual scientific knowledge, unlike much of the yeshiva and Charedi world which disparages such study, and bplease do no deny it.

    You "appear" to be an actual scientist, and I would join you in inviting every person who reads this to go to askmoses as you suggest, and read any materials that they can present. I also encourage readers to explore the subjects that interest them, to determine if what they read on askmoses or here has any relevance to them. Most of all, I hope that if they are presented with something like "I can alter the world with my thoughts, because science says that the observation creates the reality", they will have enough curiosity to look at a primer on the subject, and not just accept the version they hear to pass on as kiruv or to reject yiddishkeit.

    If you have truly read anything that I have written in this past year, you will have gotten that message. So we are actually on the same team.

    You have the last word.

    By Blogger Rebeljew, at 3:22 PM  

  • Bottom line:

    Rebeljew has contributed to the problem and not to the solution. Some of those who have left, were shaken up by your blog. They showed up clutching it in both hands.

    You taught them where to have sfekahs that Rabbonim could not help them with, reinforced their misgivings about being baalei tshuvahs, and had a generally good time making fun of frumkeit. Where did you encourage or reassure anyone that it is okay to be frum?

    Lets make the last word that it is okay to be frum, even as a scientist, a lawyer or a billionaire. I'll go even further, its nice being frum.

    Now I want to go back to the lab and do some more of that QM stuff, right after I finish checking it for chometz.

    By Anonymous Anonymous, at 5:25 PM  

  • Disclaimer:

    I did not mention, and, I did not say look at the materials on Ask Moses. I have not looked at either of those sites, I am not associated with them, and I cannot vouch for what is there.

    What I said was: If you have a science question, send it to Ask Moses and ask them to forward it to a frum professional scientist.

    By Anonymous Anonymous, at 6:20 PM  

  • And please do research the "Josephson junction". Interesting and enlightening.

    By Blogger Rebeljew, at 11:25 PM  

  • You might be interested to read Feynman's book "QED The Strange Theory of ...".

    By Anonymous Anonymous, at 7:37 AM  

  • Some of those who have left, were shaken up by your blog

    No one is going to leave frumkeit because of some esoteric discussion on quantum theory. People, however, do leave chabad occasionally because of the way chabad "spins" any popular theory and automatically attributes it to some frum source, regardless of the historical or scientific validity of the claim.

    Oh, feminism has arrived, well, funny you should mention that because Judaic sources all along have purported the idea that women are on a higher madreiga than men. Oh, global warming is a popular topic, well whaddaya know ? This is a fulfillment of "k'mayim l'yam mechasim".

    Scientific theory is not considered or analyzed in and of itself, it is simply a mekareving tool to use and discard at will. It does not even have to be science, it can be pop-psychology, Eastern medicine or any item off the pages of the National Enquirer. Once a BT comes to this realization, it becomes hard to believe so-called "proofs".


    By Anonymous Anonymous, at 9:47 PM  

  • The comment "some of those who left ..." refers to actual cases.

    What you refer to as "Chabad spin" is a different problem.

    By Anonymous Anonymous, at 10:21 AM  

  • It would be amazing when the two biggest theories come together, the quantum and the relative, I think that if we apply gravity instead of the strong force it would make a difference.

    Cheap Viagra Viagra

    By Anonymous Viagra Online Without Prescription, at 1:37 PM  

Post a Comment

<< Home