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Three-and-a-half Hakafot — Topology of Simchat Torah

Why is this night different from all other nights, asks a child on the Seder night. On this Simchat Torah I asked a different question—why is the day different from the night? Indeed, on the night of Simchat Torah, we dance seven hakafot-circuits. However, during the morning service of the next day, we only dance three-and-a-half hakafot. What is the meaning of this number—three and a half? There are a few instances the Torah, Talmud, and Rabbinic instances where this number is mentioned (e.g., during the Gaonic period, c. 590–1000 CE, in some communities in the Land of Israel, the Torah reading cycle was completed in three and a half years; Maimonides rules that only half of the tzitzit string should be dyed blue leaving three and a half strings white), but none of them [...]

Holiday of God’s Name

According to the tradition passed down to us from the Baal Shem Tov, the day after Yom Kippur is called the Holiday of God's Name. As it is explained in Kabbalah and the Chasidic tradition, each Divine name corresponds to a particular emanation of the Godly light and is associated with specific worlds and specific sephirot. For example, the name, Ekiyeh (AHYH) is associated with the sephirah of Ketter. The names Havayah (YHWH) is associated with the world of Atzilut and sephirah of Tiferet, etc. However, when we refer to the Divine Name without specifying which particular name it is, we refer to the level that is higher than all worlds and all sephirot. On Yom Kippur, we reach our very essence, the level of Yehida shebenefesh—the highest level of the Divine soul. [...]

By | October 1st, 2017|Uncategorized|0 Comments

Quantum Cheshire Cat and Resurrection

In memory of my father, Abraham Shamshin ben Reuven, ע"ה   For those of us who can't get enough of Schrödinger cat, comes a new feline—Quantum Cheshire Cat—the creation of an Israeli physicist, Yakir Aharonov. In Alice in Wonderland, Alice meets a grinning Cheshire cat. To her amazement, the cat disappears leaving only his grin behind: "All right', said the Cat; and this time it vanished quite slowly, beginning with the end of the tail, and ending with the grin, which remained some time after the rest of it had gone. Well! I've often seen a cat without a grin, but a grin without a cat! It's the most curious thing I ever saw in my life!" According to Martin Gardner, the statement "a grin without a cat" is a reference to mathematics dissociating itself [...]

Symmetry and Love — Jewish Chromodynamics

Ye are standing this day all of you before the Lord your God: your heads, your tribes, your elders, and your officers, even all the men of Israel, your little ones, your wives, and thy stranger that is in the midst of thy camp, from the hewer of thy wood unto the drawer of thy water; that thou shouldest enter into the covenant of the Lord thy God—and into His oath—which the Lord thy God maketh with thee this day. (Deut. 29:9-11) The above verses at the beginning of the Torah portion Nitzavim that is always read in the week preceding the Jewish New Year, Rosh HaShanah, are usually interpreted in terms of the unity of Jewish people: You are standing this day all of you [read: standing together in perfect unity]. This is not [...]

First Fruits and the Wave-Particle Duality of Nature

…Thou shalt take of the first of all the fruit of the ground, which thou shalt bring in from thy land that the Lord thy God giveth thee; and thou shalt put it in a basket and shalt go unto the place which the Lord thy God shall choose to cause His name to dwell there. And thou shalt come unto the priest that shall be in those days, and say unto him: 'I profess this day unto the Lord thy God, that I am come unto the land which the Lord swore unto our fathers to give us.' And the priest shall take the basket out of thy hand, and set it down before the altar of the Lord thy God. (Deut. 26:2-4) And the priest shall take the basket out of [...]

The Pilot Wave

And on the day that the tabernacle was reared up the cloud covered the tabernacle, even the tent of the testimony; and at even there was upon the tabernacle as it were the appearance of fire, until morning. So it was always: the cloud covered it, and the appearance of fire by night. And whenever the cloud was taken up from over the Tent, then after that the children of Israel journeyed; and in the place where the cloud abode, there the children of Israel encamped. At the commandment of the Lord the children of Israel journeyed, and at the commandment of the Lord they encamped: as long as the cloud abode upon the tabernacle they remained encamped. And when the cloud tarried upon the tabernacle many days, then the children of Israel [...]

Shavuot and Three States of Consciousness

Shavuot (a.k.a. the Feast of Weeks, or “Pentecost”) is the only Jewish holiday that has no fixed day in a calendar – it is always the 50th day from the beginning of counting of the Omer—Sefirot HaOmer. What is so special about the number and what is its connection to Shavuot? Shavuot is not only the culmination of the counting of the sefirah, but it is a culmination of the process of maturation of our consciousness. On Shavuot, it is customary to read the Book of Ruth (Megilat Rut). The story begins with Lot and his daughters running away from Sodom and hiding in a mountain cave. Seeing the destruction of Sodom, the daughters of Lot suspected that God in his fury destroyed the whole of humanity and they were the only people [...]

Mishkan – a Metaphor for Quantum Reality, II

Continuing the theme of my last post, Mishkan – a Metaphor for Quantum Reality, the analogy between the Tabernacle (“Mishkan”) and quantum reality goes even deeper. The quantum world is best described today by the Quantum Field Theory. According to this theory, there are no particles, only fields. When we interact with a field, it manifests itself as a quantum of the field, which, to some extent, looks and behaves like a particle. For example, when we interact with an electromagnetic field, it manifests itself as a photon – a quantum of the electromagnetic field. An electron, according to the Quantum Field Theory, is not really a particle but a quantum of the electron field, which is a quantum field that is spread across the entire universe. This quantum is an excitation of [...]

Mishkan – a Metaphor for Quantum Reality

And when the Tabernacle is set to travel, the Levites shall take it down; and when the Tabernacle camps, the Levites shall set it up… (Num. 1:51) During the wonders of Israelites in the desert, the Tabernacle (Heb. “Mishkan”), existed as a sanctuary only during their encampments. Whenever they traveled, the Mishkan was taken down and disassembled to be carried by Levites during the journey. When God commanded Moses to set the camp, the Mishkan was reassembled and set up again. Let us fast forward some three-and-a-half thousand years to the beginning of the 20 c. It was a time of great intellectual turmoil. The discovery of the atom’s structure by Rutherford, according to which atom resembled a solar system with a nucleus at the center and electrons orbiting the nucleus, was followed [...]

Half-Shekel – Metaphor for Entanglement

This they shall give, everyone who goes through the counting: half a shekel according to the holy shekel. Twenty gerahs equal one shekel; half of a shekel shall be an offering to the Lord Ex. 30:13 In this week’s Torah portion, Ki Tisa (Ex. 30), Jewish people are given the commandment of donating a coin as atonement, not just a coin – half a coin. But why half? If God thought, twenty gerahs would be too much, He could have commanded Moses to mint another coin worth ten gerahs. But no, the coin was to remain what it was—worth twenty gerahs—and Jews were to give half a coin. Don’t you find it peculiar? I don’t, because half-coins are my favorite metaphor when explaining entanglement to my physics students. What is entanglement? When obtaining [...]