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How Real Is Stuff? Part I

How Real Is Stuff? Part I

The Mystery of Matter, a three-part series


Why You Haven’t Fallen Through the Floor

From the time they first told me that the world is made of atoms, one question has always bugged me: If matter is made of mostly of empty space, why can’t my hand go through this table?

Imagine two butterflies flying over Europe—say, one over a French meadow, the other somewhere over the steppes. That’s about the space you’ve got between two typical atoms in a typical chunk of matter. Never mind that the atoms themselves are almost entirely empty space.

Think of it this way: If you took out all the empty space from between the particles that make up the atoms of which planet Earth is composed, the entire ball would fit neatly in the palm of your hand. Now imagine holding a small ball in your hand; imagine that ball exploding until its debris spreads beyond your house, beyond your city, into a space the volume of our planet. Could you walk through that? No problem. If so, why can’t you walk straight through this planet?

You would think that’s the first thing they would want to explain in grade school physics: What exactly is it about this table, or this floor, or keyboard, or any chunk of matter for that matter, that won’t allow another piece of matter to enter into its space? I mean, it’s called physics, right? You would think they would be teaching why physical things are so physical.

Well, after grade school, I did get a few explanations. All quite mystifying. But the winning answer that actually works has a lot to say not just about atoms and matter, but about the universe and life in general.1

You can’t walk through a wall for much the same reason you can’t walk through a baseball diamond when a game is in play.

Here it is: The reason you can’t walk through a wall is much the same reason you can’t walk through a baseball diamond when a game is in play.

Cosmic Baseball

Say one sunny afternoon you and your buddies turn up at your reserved field with all your equipment, and the parks board has messed up again. Another league has their game scheduled on the same diamond overlapping into your time, and they’re only in their first play.

But hey, there’s lots of space, right? Look at those huge gaps of empty space between first and second, for example. So let’s say we move another pitcher just next to where these guys have a pitcher, another shortstop just a few feet from their shortstop—and so on, until we have two games playing in the same space. And why stop there? I mean, there’s so much space, right?

Makes sense, but the other league doesn’t seem happy about it. What’s their excuse? “You can’t do that!” Period. There can only be one pitcher, one batter, one shortstop, one of every position. Those are the rules.

Same with the wall, the table, the planet and your hand. They’re all in the same league, playing the same game.

Matter is made of particles we call fermions (as opposed to force, which is carried by bosons). The Fermion League has two teams, the Leptons and the Quarks. Each team has six players. The Quarks have the more colorful names: up, down, strange, charm, bottom and top. The Leptons include that familiar-to-all electron, while the other names sound like the children of a mixed Oriental-Italian marriage: electron-neutrino, muon, muon-neutrino, tau and tau-neutrino. That makes twelve, but then there are the Anti-Leptons and the Anti-Quarks, making 24 in all (and you don’t want to know what would happen if all of them met).

These team players combine to comprise bigger fermions in the form of protons, neutrons and atoms. (They can also combine to make atoms that are bosons, which is pretty strange.) But, no matter how they combine, there is one rule they all keep: No two of them can do exactly the same thing.

For physicists, “doing the same thing” means occupying the same quantum state. There are four numbers of the quantum state, and one of those numbers tells us which shell the particle occupies—which (sort of) means “where it is.” Turns out that two particles can be in the same place at the same time—but only if the other three numbers of their quantum state differ. For example, maybe one is moving with greater momentum than the other, or in a different direction. Or it has an opposite spin (which, by the way, has nothing whatsoever to do with spinning).

So, what happens when my hand hits the table? Well, here comes a pile of atoms with their particles, and along comes another pile of atoms with their particles, and if they’re going to move here, a lot of those particles are going to match all four quantum states of some other particles.

Two pitchers in the same diamond. Against the rules. Either one of those particles is going to have to be promoted to a higher energy state, or it will just have to stay out of the space of this atomic shell. Absent the huge surge of energy needed to promote all those particles, your hand stays out of the table.

Variety Is Everything

Think about it, and you’ll realize that this rule goes far beyond keeping you from falling into the depths of planet Earth. This is the rule that keeps the universe interesting. Because if particles were allowed to copycat one another, how much variety do you think the universe would contain? All atoms would act as hydrogen and helium, and that would be it. And what would stop everything from being in the same place at the same time? It’s only because every particle must be different from every other particle in such things as energy level, momentum and position that we end up with a hugely variegated universe—or any universe at all.

Wolfgang Pauli (Bettina Katzenstein / ETH Zürich)
Wolfgang Pauli (Bettina Katzenstein / ETH Zürich)

This principle was discovered by one of the fathers of quantum physics, Wolfgang Pauli. If Pauli would have rewritten Genesis, he might have begun, “In the beginning, G‑d granted every particle of matter exclusive rights. And so, a multitude of things came into being.”

Pauli spoke about the “unity of being” of the universe, and sought a unity of the rational and the mystical.

Pauli didn’t rewrite Genesis. But he did hook up with Carl Jung. Pauli’s classmate and confidant, Werner Heisenberg, describes him speaking in rather mystical terms about “the unity of all being,” describing how the particles of the universe follow a kind of “psychophysical interrelation”2—as though the entire cosmos was one great, deep psyche. How else could he explain how all these particles knew just what they were supposed to be and what rules to follow? Heisenberg quotes Pauli discussing his struggle with the theologians, “wrestling with the One,” satisfied with neither the rational nor the mystical:

I consider the ambition of overcoming opposites, including also a synthesis embracing both rational understanding and the mystical experience of unity, to be the mythos, spoken or unspoken, of our present day and age.3

Pauli meant mythos in a Jungian sense, as the very soul and sustenance of our society, that which provides it cohesion and drives it forward. We are all seeking that synthesis, a vision within which we can frame Pauli’s wonderment.

White Space

“G‑d looked in the Torah and created the world,” says the Zohar.4If so, as Nachmanides writes in his introduction to Genesis, whatever exists in this world first exists in Torah. So, I figured something as core to reality as Pauli’s exclusion principle should be readily apparent somewhere in Torah.

What do you know, it didn’t take long to find it there.

Look inside a Torah scroll. Unlike Arabic or Sanskrit or cursive writing, Hebrew letters don’t string together. When writing a Torah scroll, the rules dictate that no two letters may touch one another. Each letter must be entirely surrounded by white space.5

Now, because the Torah scroll is a singularity, every one of its basic elements (letters) is of existential value. Practically speaking, the rules are that if one letter is missing, that scroll no longer has the sanctity of a Torah scroll. We tie it up and put it away until it can be fixed.

What’s interesting is that the same applies to two letters touching one another: If any letter is lacking its white space, the wholeness of that Torah is lost.

Paradoxically, integrity of the whole is expressed by exclusivity of the parts.

Paradoxically, integrity of the whole is expressed by exclusivity of the parts.6

(There’s an application here, too, in our personal lives: Like those letters, every soul G‑d sent down to this earth has its particular mission. No two overlap, or even touch each other’s borders. Suppressing that diversity subverts the wholeness of the community.)

Another instance: The Tabernacle we constructed in Sinai and the Temple in Jerusalem are described as miniatures of the entire cosmos. Although they were members of the same Levite tribe, a kohen (priest) was forbidden to do the job of a levi (attendant), and a levi was forbidden to do the job of a kohen. Furthermore, a levi who was appointed to sing was forbidden to help a levi who was appointed to open a gate, and vice versa.7All this from an explicit statement in the Torah: “Each person on his task and to his load.”8

There you have it again: Oneness is expressed as diversity.

How Smart Is a Particle?

Now, there’s a difference here. The letters in the Torah don’t touch one another because the scribe knows the rules and sticks to them—just as the baseball players stick to their bases. The same with the kohanim and levi’im in the Temple.

But when it comes to quantum physics, how does each particle know it’s supposed to keep this rule?

Bigger problem: How does each particle know the state of every other particle in the universe, so that it won’t imitate it?

Even bigger problem: Pauli’s exclusion principle is just that—a principle. Yet it’s due to that principle that matter occupies space—and that we can touch matter. Meaning that the whole concept of matter and substance as we perceive it is really nothing but a baseball-diamond rule. Now, isn’t that strange? How does a rule become so tangible that we can touch it with our hands?

We touch with our fingers not stuff, but deep wisdom. The ultimate wisdom.

We like to bury those issues by saying there are “fields” or “laws.” Words like those are useful at times. But let’s not allow them to blur a deep truth staring us in the face: We touch with our fingers not stuff, but deep wisdom. The ultimate wisdom.

What’s so wise about matter? That will have to wait until the sequel, part 2.

For the best, simplest exposition of this I could find online, see Ask a Mathematician/Ask a Physicist, Feb. 7, 2011.
Quoted in Werner Heisenberg, Across the Frontiers, trans. Peter Heath (Harper & Row, New York, 1974), pp. 35–36.
Concerning Pauli’s relationship with Jung and his struggle with reason and mysticism, see Atom and Archetype: The Pauli/Jung Letters, 1932–1958 (Princeton University Press, 2001). For a fascinating account that includes Pauli’s and Jung’s interest in Kabbalah, see Arthur I. Miller, 137: Jung, Pauli, and the Pursuit of a Scientific Obsession (W. W. Norton & Company, 2010).
Zohar 2:161a.
Maimonides, Mishneh Torah, Laws of the Sefer Torah, Tefillin and Mezuzah 1:19.
See Sichos Kodesh 5744 3:1455.
Maimonides, Mishneh Torah, Laws of the Vessels of the Temple, ch. 3.
Rabbi Tzvi Freeman, a senior editor at, also heads our Ask The Rabbi team. He is the author of Bringing Heaven Down to Earth. To subscribe to regular updates of Rabbi Freeman's writing, visit Freeman Files subscription. FaceBook @RabbiTzviFreeman Periscope @Tzvi_Freeman .
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Craig Hamilton Sandwich, MA August 7, 2016

Particle Physics Is a Path to Idolatry With particles, once one finds one, then to discover the next one it is ever harder to get to the next smallest particle, each smaller particle found becomes ever more elusive. With every particle found, there is hope to find another smaller one ad infinitum. It is a religion with a long slow path to idolatry. Reply

yitzchak April 18, 2014

Thank you Why cant "beyond beyond" make isness? Reply

Craig Hamilton Sandwich, MA August 14, 2013

The Word "Hebrew" Is the The Translation of Matter from English to Hebrew The world was created with ten divine Hebrew utterences. From these utterances the rest of the world was created. Thus, Hebrew letters are the building blocks of matter. And, as a result; it can be said that the vocabulary of Hebrew is the very matter that makes up this world, and therefore Hebrew equals matter, as one definition of the word Hebrew. Reply

Ilana Solomon Jerusalem August 8, 2013

Unbelievable You explained such a complex matter in an amazing way. It really opened up my eyes to a whole new way of seeing physics and gave me a deeper appreciation of Hashem's wonders and infinite wisdom. Reply

Doreet Eugene Oregon August 4, 2013

the matter of suffering and poverty, why does God allow it? there was one comment that said," if we are the creation of God, why all the suffering, poverty, and pain of mankind? Why does he do that to us?" And then I remembered, HOW babies and children become adults. They go through such a hard time, learning to eat, learning to crawl, learning to speak; learning to not do this or not do that, learning to walk learning to read, and going to school; they get lots of bruises and pain, and frustration all through growing up, confusing teenage, into becoming an adult. They do not understand all their past sufferings and struggles, until they become an adult also.

I think the comparison is applicable. Reply

bvw Washington Crossing August 1, 2013

Analogies only hold so much water We pass through gas and dust and empty space easily. We pass through liquids not so easily but we still pass. Fermions and Bosons are named per the counting method they follow. Bose-Eistein or Fermi-Dirac.

Fermions insist on being distinguishable in any counting -- including the counting of who is where, where exactly is Able, Cain? Bosons are happily indistinguishable no matter how counted, Rachel is Leah.

What makes us unable to pass through a solid floor is our togetherness. Our fermions like to hang around and protect their bosons. Electrons are fermions, inside the nucleus the protons and neutrons act like bosons when stable. Our atoms form compounds, they hang together according to rules, just as the floor does.

Analogies only hold so much water. Reply

Sue Kanata July 31, 2013

Tinaratin Earler than possible, Royal blue flowers come to mind... Reply

David Chester Petach Tikva, Israel July 31, 2013

Like Meets Like The reason why (for example) my hand cannot pass through a solid wall is that they both consist of the same kind of stuff. If the atoms in then wall have spaces between them and my hand does too, there is no way that like meeting like can yield. I don't see the need for partical physics to explain this.

When we want to "pass through" an aparently solid object we use a tool having harder physical properties where the molecules of it are closer packed and to which we can concentrate the applied force. If we wish to cut through a wall we use a chisel. But what should we use when we wish to drive our prayers, so that they can have an influence on the walls surrounding Heaven? Reply

Benny Toronto July 30, 2013

Collapse of the Wave Function YK & thank you. This was beautiful. Complexity couched in simplicity. The ties to Chassidus are all over this. Perhaps, here's another:

Copenhagen Interpretation (pretty sure this has been lab-proven): Prior to our human observation, each particle occupies each possible state, simultaneously. It is both a photon wave and particle, light and matter, at once. Kind of here & not here at once. Sounds familiar - The Ark was also here & not here at once, in the holiest, innner sanctum of the Holy of Holies. That's signature of Hashem. G-d is capable of both opposites at once - elephant in eye of needle. Infinite & finite and above both, at once. So, we see this signature underlying all of reality, in absolutely everything. The signature of Hashem is everywhere. Just scratch & sniff! (smell = highest sense of the soul) :-) Reply

Ilya Solon, OH July 29, 2013

Confusion... Dear Rabbi, beautiful article, blew me away by its simple intent but very complex content. Here is a statement that confused me because of my ignorance and lack of knowledge "G-d looked in the Torah and created the world". Is Torah beyond the rules? Reply

Vicki Atkinson GONZALES July 29, 2013

coincidence? My husband and I, just this week have been introduced to a teaching on Quantum Jumping. I am kind of having an issue with it because it is the thought of meeting your alternate self and changing the dynamic of your current life. This would kind of tie into what you are saying here about no matter being the same. Very confusing to me, I am no scientist that's for sure. Do you have any opinions on this? Reply

Anonymous Derby, KS July 28, 2013

Beautiful example. Another beautiful example of how every one of us is a light to the universe. Although we all occupy different space, we all are necessary in our lives and our purpose. The universe would not be whole without any of us. Reply

Jorge Munuzuri Qro./Mexico July 23, 2013

Have I understood correctly? I'm not living up to this article, however I'm so accustomed to Chabad's moderator benevolence that I dare to write what follows; we certainly touch with our fingers and maybe while touching we'll be able to feel G-d's presence but here the article deals with subatomic particle behavior and it seems that this theory is very useful in Chemistry. Regarding the "Bigger problem: How does each particle know the state of every other particle in the universe, so that it won’t imitate it?" I love Rabbi Freeman's ultimate statement --with our fingers we touch G-d's creation, in Chemistry, substances touch each other according with G-d's rules i.e. according to the principles of the physics laws. Have I understood correctly? Reply

Irving Newman Henderson, NC July 19, 2013

The concrete that binds atoms and empty space into something tangible is a mixture of awareness and agreement, Why does our computer not fall through the table onto the floor? Because we are all conscious of the fact that we all agree that the table is solid. The table is solid simply because we agree that it is. Reply

Tzvi Freeman July 18, 2013

Re: Spooky action at a distance... I was thinking of bringing that in, but, as you write, it's moving outside of exclusion principle stuff. But non-locality, as Bell called it, is something I just have to write on. So, working on that now (no promises). Meanwhile, there's two more in this series coming up. Reply

ruth housman marshfield, ma July 18, 2013

help me, I'm falling We have many sayings, such as 'that statement floored me. The applause went through the roof." It is interesting to contemplate space, energy, matter and what matters. The end point of physics is a sense of wonder and mystical experience because the quantum world is a world of probability. We know, even the participation of an observer appears to alter what happens (Schrodinger's cat/ The Heisenberg Uncertainty Principle). It is the world of Alice, where we got our name, quark.

A quarky quirky, universe for sure. And it could all exist, what is tiny beyond vision as a kind of mirroring of what is perceived on a macro level. Not a new idea. The poets see this in expanding metaphors. It is All One, even as, in, our beautiful Shema, the watchword of our faith. Reply

Ephraim Ny July 18, 2013

Awesome Thank you Reply

Craig Hamilton Sandwich, MA July 17, 2013

Orbitals Or Not Quantum states, such as is described by shells, is like Chem. 101. As one gets more advanced, sometimes the nice little molecular tinker toys, where electrons are represented in outer shells, no longer add up to the point where it could be said, "That's impossible, according to what my toys say. But, it works!" In this way, quantum theory is tremendously useful, but sometimes in the real lab, we have to forget these things, and use other representations. In reality, all particles operate on their own scheme, which is a part of a greater picture, such that the reality of the baseball game changes by orders of magnitude, entirely different games even on the same field, based on size, such that there is possibly no end to the large or the small realities of the cosmos. Reply

Ethan Miller Santa Cruz, CA July 17, 2013

Spooky action at a distance... "Bigger problem: How does each particle know the state of every other particle in the universe so that it won’t imitate it?"

This is the core conundrum of quantum entanglement, a problem characterized by Einstein as "spooky action at a distance". Two particles are created with quantum states that are identical except for one factor such as spin, where both are indefinite. Then, when one is measured for spin, the other *must* take a different value, no matter where in the universe it is. How does the particle "know"?

Minor nit: this isn't directly the Pauli exclusion principle, but rather related to quantum superposition. Reply

Anonymous July 17, 2013

How Real Is Stuff My dear Rabbi Freeman, I simply love your teachings. Why can we have them more often? This make me think of the diversity in One. And through this knowledge come to the conclusion of the "other" dimension. Hashem, blessed be He, created a world with diversity, from His One-Ness. And if we look closely, from His essence radiates the diversity of all. All we need to do is to transcend to that Infinite Space, and by doing so we will become part of that miniature tabernacle that belongs to each and everyone of us. Different in matter, but equal in essence. Thank you. I told you before, I wish you were my teacher. But then, we all in the blog have a chance to learn from you. Reply

A growing collection of essays on motifs of Chabad thought as they relate to today's world.