History and culture December 21, 2021 Updated: September 13, 2026 21 min read Urh Zagradišnik

Acoustic Levitation of Stones: A Tibetan Mystery Between Testimony and the Physics of Sound

The story of Tibetan monks allegedly lifting multi-ton stones with drums and trumpets contains strikingly precise measurements — but how strong is its source trail, and what does modern acoustic physics actually say about such a feat?

The story is almost cinematic. At a remote Tibetan monastery, monks are said to have arranged thirteen drums and six long trumpets in a precise arc. A large stone block was supposedly placed in a bowl-shaped depression; after several minutes of drumming, horn blasts and chanting, it allegedly began to rock, lifted from the ground and travelled in a long arc to a ledge roughly 250 metres higher. The account is so specific that it gives distances, instrument dimensions and even an alleged flight time.

That precision is one reason the story has circulated for decades as one of the most attractive examples of lost technology. But a precise description is not the same thing as an independently verified event. When we trace the claim backward, we do not arrive at a surviving film, laboratory record or archival eyewitness report. We arrive at a chain of later retellings in which the same measurements are copied again and again.

At the same time, the second half of the story is real: sound can exert force. An acoustic wave carries energy and momentum; a suitably shaped sound field can use radiation pressure to oppose gravity and levitate particles, droplets and even objects larger than the acoustic wavelength. Modern acoustic levitation is therefore not fantasy. But that does not establish that drums and trumpets can lift a multi-ton stone hundreds of metres into the air.

This article therefore separates four levels that are easy to blur in anomalous-history stories: what is documented in historical sources, what established physics permits, what is merely calculable under idealized conditions, and what remains unverified testimony. The goal is not to close the mystery, but to put it on ground firm enough to see which part is genuinely unusual and which part emerged only through later retelling.

A story that is almost too precise

The most widespread version says that a Swedish doctor known only as Dr Jarl travelled to Tibet in 1939 and observed construction on a rocky ledge. About 250 metres from the cliff was allegedly a stone slab with a bowl-shaped depression. Nineteen instruments were placed in a 90-degree arc at a radius of 63 metres: thirteen drums and six long trumpets. Several versions also provide drum dimensions and trumpets measuring 3.12 metres.

The stone is described in later retellings as roughly 1.5 metres long and one metre wide; some versions add a height of about one metre. After roughly four minutes of increasingly loud music, it supposedly began to move and then followed a parabolic path to the ledge high in the cliff. The account adds that five or six stones per hour could be moved this way.

These are strikingly concrete details. But source auditing asks where they came from. If ten websites repeat the same dimensions from the same text, we do not have ten witnesses. We have one narrative copied ten times.

From Jarl to Kjellson, Alexandersson and Cathie

The central name in the transmission of the story is Swedish aviation engineer Henry Kjellson. His 1961 book Försvunnen teknik is bibliographically well attested, and descriptions of the book explicitly mention a chapter about Tibetan monks allegedly lifting enormous stone blocks with sound waves. Kjellson was a real and technically trained person; that fact alone does not validate every account he collected.

The later transmission introduces Olof or Olaf Alexandersson, author of a text in the journal Implosion no. 13. Reproductions available today retell the Jarl story with nearly the same geometric measurements. Bruce Cathie later incorporated it into a text on acoustic levitation and linked it to his own ideas about Earth grids and harmonics. Cathie's version helped carry the story into English-language alternative literature and later onto the web.

The direction of evidence matters. Alexandersson and Cathie are not independent eyewitnesses. They are transmitters or interpreters of an account that points back toward Kjellson and Jarl. Later publications do not increase the number of independent witnesses if they all descend from the same core story.

The weakest link is the alleged eyewitness

Dr Jarl remains the central problem. In publicly accessible documentation he cannot be securely identified by full name, institution and a verifiable journey to Tibet. The two films he allegedly shot have never been made public. The story says that an English scientific society confiscated them, but the institution is named inconsistently or generically and no verifiable archival record of seizure or classification has surfaced.

Swedish archival researcher Håkan Blomqvist reports that journalist Clas Svahn investigated the Jarl trail and spoke with Jarl's widow; according to that secondary account, Jarl had a very lively imagination and a reputation as something of a mythmaker. This is not a primary archival document either, but it is important counter-evidence because it comes from an attempt to investigate the alleged witness rather than from another repetition of the levitation story.

The safest conclusion is therefore not that Jarl must have been invented, but that his testimony does not currently meet the level of verifiability needed for historical proof. Until a primary diary, film, correspondence, institutional record or independent contemporary source is identified, the account remains second-hand testimony.

Rudolf von Linauer: a second trail, not independent confirmation

The story has another intriguing branch. Rudolf von Linauer published an article about Tibet in the Swedish newspaper Stockholms-Tidningen in September 1939 and reportedly lectured in Stockholm that same year. That newspaper trail matters because it shows that Linauer's Tibetan narrative is not a modern internet invention. It predates Kjellson's 1961 book.

But the documented existence of an article is not the same as a documented journey. After researching Linauer's biography, Blomqvist found evidence of Asian contacts and knowledge of Chinese culture but no decisive proof that Linauer actually visited a secret Tibetan monastery and witnessed stones being lifted by sound. The Linauer account is historically interesting, yet still an unverified claim.

Two similar stories can look like mutual confirmation. Before treating them as two independent witnesses, however, we would need to show that they did not arise from the same intellectual circle, contacts or already circulating stories. At present that cannot be demonstrated.

What acoustic levitation actually is

Sound is not merely information perceived by the ear. An acoustic wave carries energy and momentum. When it reflects, refracts or scatters from an object, the time-averaged effect of the wave can create acoustic radiation pressure and therefore a net force. If the sound field is shaped correctly, that force can balance an object's weight and stabilize it in space.

This is not the cancellation of gravity. Gravity remains and pulls downward; the acoustic force opposes it or traps the object within a stable region of the pressure field. Classical levitators often use standing waves between an emitter and a reflector, while modern phased arrays can create more elaborate traps and move them electronically.

In 2015 a Nature Communications team demonstrated single-sided ultrasonic traps for millimetre-scale particles. In 2017 Andrade and colleagues demonstrated stable levitation of a 2.3-gram object larger than the acoustic wavelength. Later methods have pushed the size boundary further. The underlying phenomenon is therefore well documented, but the scale of public experiments remains far removed from a multi-ton building block.

Laboratory acoustic levitator at Argonne National Laboratory suspending small droplets with a sound field. — Documented acoustic levitation is real and measurable. This laboratory system is deliberately distinct from the Tibetan story: it shows what an experiment must actually control — field geometry, frequency, intensity and the size of the levitated object. Image: U.S. Department of Energy / Argonne National Laboratory / Wikimedia Commons Public domain — U.S. federal government

Size is not the only problem — force and field control are decisive

In levitation it is not enough to ask whether an object is larger than the wavelength. Mass, area, density, shape, distance from the emitters, acoustic power, phase and field geometry all matter. A lightweight polystyrene object several centimetres across is a fundamentally different engineering problem from a stone block with thousands or millions of times more mass.

If we take a later version of the Jarl story literally and assume a granite block roughly 1 × 1.5 × 1 metre, its mass would be about four tonnes. Merely balancing that weight over a bottom area of roughly 1.5 square metres requires an upward force of about 40 kilonewtons. In a highly simplified ideal model of a perfectly reflected acoustic wave, that corresponds to radiation pressure on the order of 26 kilopascals and acoustic intensity of several million watts per square metre — a sound-pressure level on the order of roughly 187 dB.

This is not an exact calculation of the alleged Tibetan apparatus. We do not know the actual mass, instrument spectrum, environmental reflections or resonances, and at such amplitudes simple linear acoustics is no longer a complete description. The calculation makes a more modest point: the force requirement for a multi-ton stone is enormous. The word 'resonance' by itself does not remove the energy and stability requirements.

Resonance can amplify response, but it cannot replace missing energy

Resonance is real physics. When a system is driven near one of its natural frequencies, the response amplitude can become large, so comparatively modest periodic excitation can produce a strong mechanical response. Bridges, musical instruments, cavities and mechanical structures demonstrate this every day.

But resonance does not mean unlimited force without energy input. Real systems have losses, damping, nonlinearities and material limits. Levitation is also a stability problem: the object must not merely leave the ground; forces must remain directed and controlled so that it is not spun, ejected or dropped.

That difficulty becomes especially severe for Jarl's alleged trajectory. The instruments were supposedly fixed 63 metres from the launch slab, while the stone then travelled for minutes toward a ledge hundreds of metres away and high above them. Modern remote acoustic traps that move objects rely on carefully phase-controlled emitters or field geometries that produce stable trapping regions. The described drums and trumpets contain no known mechanism for a trap that follows the stone through the whole flight.

Detail is not proof — but it makes a claim testable

One strength of the legend is that it is specific enough to test in part. If it said only that monks 'moved stones with sound', it would be almost impossible to falsify. The 63-metre radius, nineteen instruments, their dimensions and the alleged trajectory create questions about wavelengths, power, directionality and stability.

That is a useful lesson for anomalous claims. More detail does not automatically mean more credibility; detail is valuable because it creates more points where a claim can meet independent evidence. If an original Jarl diary, instrument photograph, institutional archive or modern measurement of a comparable setup were to surface, the evaluation could change.

Until then we must preserve the distinction between 'physics includes acoustic force' and 'this historical event occurred'. The first is an experimental fact. The second is a historical claim that requires its own evidence.

Why the story survives

The account combines three powerful motifs: secret knowledge from a remote culture, an engineering-style description full of measurements, and a real physical phenomenon that for a long time looked almost magical to non-specialists. Once we see laboratory ultrasonic levitation today, the old account feels intuitively more plausible. But similarity at the level of principle is not evidence of historical implementation at a radically different scale.

The story also contains the motif of a lost film and classified documentation. That protects the claim from testing: missing evidence can be reinterpreted as evidence of suppression. Methodologically this is dangerous because almost any absence can be turned into apparent support. A serious source audit has to treat the absence of the film as absence of the film, not as proof that it was confiscated.

None of this makes the history uninteresting. It is remarkable enough that we can trace a Swedish network around Kjellson, Alexandersson and Linauer and watch the narrative develop decades before the internet. The mystery does not disappear; it changes shape.

What we can currently say

The strongest layer is the physics: acoustic radiation pressure exists and sound can levitate objects. It is also documented that Henry Kjellson published an account of Tibetan stone lifting in the early 1960s and that Linauer was publishing Tibetan narratives in Sweden in 1939.

The next layer is possibility: a sufficiently powerful and carefully shaped acoustic field could in principle generate large forces. But scaling to a multi-ton block requires extreme power, control and stability that publicly documented modern experiments do not approach in the form described by the legend. Modern levitation therefore does not validate Jarl; it only shows that the phrase 'levitation by sound' is not itself physically meaningless.

The weakest layer remains the historical event. We have no verifiable primary Jarl record, public film, identified scientific institution or independent contemporary measurement. The most defensible conclusion is therefore open but not indecisive: acoustic levitation is real physics; the Tibetan account is an interesting, partly traceable, but still unverified testimony. If new primary evidence appears, the assessment should change with it.